CN1917954A - Particulate water absorbing agent and method for production thereof, and water absorbing article - Google Patents

Abstract

A particulate water absorbing agent being prepared by the surface crosslinking treatment of a water absorbing resin having a crosslinked structure, characterized in that (i) a mass average particle diameter (D50) is 200 to 600 mum and particles having a diameter of not less than 150 and less than 850 mum account for 95 to 100 wt % of the total particles, (ii) a logarithmic standard deviation (sigmazeta) of its particle size distribution is 0.25 to 0.45, (iii) a degree of compression is 0 to 18 %, and (iv) a surface tension of a supernatant liquid being obtained four minutes after the dispersion of 0.5 g of said particulate water absorbing agent into 50 ml of a physiological saline solution at 20 DEG C is 55 mN/m or more. The particulate water absorbing agent exhibits high fluidity in a dry state, while retaining high absorbing capability, and can be free from blocking, caking and the sticking to an apparatus or the like, and, when the absorbing agent is contacted with a liquid to be absorbed, the liquid is less prone to reduction of the surface tension, and further, the absorbing agent exhibits enhanced fluidity and bulk density without detriment to absorbing characteristics.

Description

Particulate water-absorbing agent with and manufacture method and absorbent article

Technical field

The present invention relates to the water-absorbing resins be main component particulate water-absorbing agent with and manufacture method and absorbent article.Relate in particular to and under drying regime and sucting wet state, have good flowability, and have good such as volume density the coccoid characteristic and do not lose the particulate water-absorbing agent and the absorbent articles of its water absorption character, it has stable water absorption character, this particulate water-absorbing agent is used in disposable diaper, sanitary towel, incontinent person with in the absorber of the amenities of pad etc. the time, the amount of returning of absorbed liquid is few in described particulate water-absorbing agent and the absorbent articles, and it has the excellent absorption characteristic.

Background technology

In recent years, for absorb body fluid (as, urine, blood etc.), water-absorbing resins is widely used as disposable diaper, sanitary towel, the incontinent person main composition material with hygienic materials (absorbing articles) such as pads.The known example of above-mentioned water-absorbing resins has: the polyacrylic acid of crosslinked part neutralization, starch-acrylonitrile grafting the polymer that decomposes, starch-acrylic acid-grafted the polymer of neutralization, the vinyl acetate-acrylic copolymer of saponification, crosslinked carboxymethyl cellulose, the acrylonitrile copolymer of hydrolysis or the acrylamide copolymer of hydrolysis, or crosslinked acrylonitrile copolymer or crosslinked acrylamide copolymer, crosslinked cationic monomer, crosslinked isobutene-maleic acid, crosslinked 2-acrylamide-2-methyl propane sulfonic acid and polymerizing acrylic acid thing etc.All the time, the desired water absorption character of water-absorbing resins is: the gel strength of the high-absorbility under high-absorbility, the especially load when contacting with waterborne liquid such as body fluid, good infiltration rate, better fluid permeability, good expansion gel, the good absorbability when the matrix material of property of water-bearing liquid absorbs water etc.

These water-absorbing resins all have uniform cross-linked structure and all water insoluble in polymer inside.Usually, for obtaining above-mentioned water absorption character crosslinking Treatment is further carried out so that particle has the crosslink density gradient with crosslinking agent etc. in the surface of its particle.Therefore, improved water-absorbing resins absorption speed, prevent to generate and do not allow residual thing, improve gel strength, improve absorptivity under the pressurization situation, prevent gel blocking, improve logical fluidity.

For example, please disclose text, spy in European patent 0349240, European patent 0605150 and the flat 7-242709 of Te Kai opens and discloses near the technology (hereinafter referred to as prior art 1) that has the surface-crosslinked processing of crosslink density gradient the relevant particle surface that allows water-absorbing resins in the open text of flat 7-224304 application, United States Patent (USP) 5409771, United States Patent (USP) 5597873, the United States Patent (USP) 5385983 etc.

Except above-mentioned technology, the spy opens and discloses in the open text of clear 61-58658 application about to improve the technology that logical fluidity is absorbent material purpose, that be made of water-absorbing resins and metallic soap.In addition, water-absorbing resins not only needs to have above-mentioned water absorption character, also need to have the following advantages: in the following cases, water-absorbing resins has good coccoid flowability under drying regime and sucting wet state, adhere on the device etc. so that water-absorbing resins is less: when the manufacturing of water-absorbing resins and carrying, when making water-absorbing body, when moisture absorption processing water-absorbing resins and fiber-based material.When having the water-absorbing resins of good coccoid flowability when attempting preparation in moisture absorption, the someone has proposed wherein to be added with the absorbent articles of inorganic substances such as unformed silica or kaolin.Especially for example, United States Patent (USP) 4734478, spy open in open text of clear 59-80458 application and the United States Patent (USP) 5453323 and disclose the technology that relates to the water absorbing agent that comprises inorganic substances coccoid and absorbent resin powder.Except that the technology of adding inorganic substances within it, the spy opens clear 63-105064 and applies for also having put down in writing in the disclosed text and add stearic acid and the inorganic material powders water absorbing agent (hereinafter referred to as prior art 2) as additive within it.

In addition, the water absorbing agent of interpolation quaternary ammonium salt as additive disclosed in United States Patent (USP) 5728742.In addition, the spy opens in open text of flat 9-136966 application and the European patent 0001706 and discloses the particulate water-absorbing agent that adds polysiloxanes, polyethylene glycol or the polypropylene glycol etc. of modification.In addition, the spy opens in the open text of flat 8-143782 application and discloses the particulate water-absorbing agent (hereinafter referred to as prior art 3) that contains condensate class dispersant.

In addition, open in the 2003-82250 communique (put down on March 19th, 15 open) the fair 6-39485 communique of spy (put down on May 25th, 6 bulletin), No. 3283570 communique of special permission (putting down into login on March 1st, 14) and spy and to have put down in writing, in order to prevent to generate insoluble residual thing and gel blocking, handle the particulate water-absorbing agent (hereinafter referred to as prior art 4) of water-absorbing resins with surfactant.In addition, the motion of attempting improving volume density is also arranged.For example, open to have put down in writing in the 2000-302876 communique (put down on March 19th, 15 open) the spy and carry out after grinding cross-linked polymer particle surface-crosslinked and the water-absorbent resin powder that is fractured into amorphous that obtain has big volume density and have absorptivity (hereinafter referred to as prior art 5) under the good pressurized state.

But, in the middle of the above-mentioned technology, the coccoid flowability when coccoid flowability under the drying regime and moisture absorption are arranged is inadequate, the absorbent properties under the pressurized state significantly reduce, the problems such as surface tension reduction of absorption liquid when water-absorbing resins contacts with absorption liquids such as urine.For example, in above-mentioned prior art 1, the coccoid flowability when coccoid flowability under the drying regime and moisture absorption is not high enough, and water-absorbing resins is difficult to handle.In above-mentioned prior art 2, though the coccoid flowability when adding inorganic substances and improved moisture absorption, coccoid flowability and water absorbing properties under the drying regime decline to a great extent, and make that water-absorbing resins is difficult to handle.As a result, use the absorbing articles of this water-absorbing resins not have sufficient water absorption character.Especially open in the technology that clear 61-58658 puts down in writing the spy, the amount of the metallic soap that is added in water-absorbing resins is 1～60 weight % normally, preferably 5～80 weight %.When adding the metallic soap of volume like this, character such as the hydrophobicity of metallic soap, bullet water-based, surface-active have a strong impact on the absorbent of water-absorbing resin.In prior art 3, the illiquidity when moisture absorption is arranged, the problems such as surface tension reduction of absorption liquid when water-absorbing resins contacts with absorption liquids such as urine.For example, when using water-absorbing resins in disposable diaper, the water absorption character of the absorbent article of the absorption liquid amount of returning increase etc. descends, so can't be referred to as perfect.

In addition, existence is many because of the use amount of the surfactant in the water-absorbing resins in prior art 4, not too economical, and the surface tension of absorption liquid descends when absorption liquids such as particulate water-absorbing agent and urine contact, and then causes that the amount of returning (re-wet) increases when for example using disposable diaper etc. and influence the problem of the absorbent of particulate water-absorbing agent.

Though the water-absorbent resin powder that is fractured into amorphous in prior art 5 has the water absorption rate under high volume density and the good pressurized state, but for obtaining these characteristics the surface of cross-linked polymer is ground, so increased the operation that makes powder.In addition, also need to remove the micro mist that when the surface of cross-linked polymer is ground, produces.The problem that trouble when therefore this technology has cost and manufacturing increases.

The present invention studies in view of the above problems, its purpose is for providing the particulate water-absorbing agent with following characteristic: the good coccoid flowability under good flowability during (1) moisture absorption and the drying regime makes and be easy to handle water-absorbing resins when carrying, and make its less adhering on the production equipment, (2) absorptivity under the high pressurized state is arranged, (3) it has good water absorption character, make itself and urine prevent the capillary reduction of absorption liquid when waiting absorption liquid to contact, flowability of (4) water-absorbing resins and volume density stably increase and do not damage water absorption character.

Summary of the invention

Present inventor of the present invention pays close attention to following situation: but if can realize good fluidity, can keep high water absorbing properties, when absorption liquids such as particulate water-absorbing agent and urine contacts, control to Min. the capillary decline of absorption liquid, be easy to prepare absorbent articles such as diaper so, and when particulate water-absorbing agent is used for absorbent article, can provide the amount of returning few good absorbent article with particulate water-absorbing agent.Based on the further investigation to above-mentioned situation, the inventor finds, by using the surface to be crosslinked processing and having the water-absorbing resins of specific granularity and the lubricant or the surfactant of coccoid, can achieve the above object.Therefore, they have finished the present invention.

Promptly, particulate water-absorbing agent resin of the present invention comprises and has been undertaken surface-crosslinked processing and water-absorbing resins that have cross-linked structure by adding surface conditioning agent, the feature of this particulate water-absorbing agent is, (i) mass median diameter (D50) is 200～600 μ m, and by whole particulate water-absorbing agents is that 100 weight % calculate, the particle diameter that contains 95～100 weight % is to be equal to or greater than 150 μ m and less than the particulate water-absorbing agent of 850 μ m, (ii) the logstandard deviation of size distribution (σ ζ) is 0.25～0.45, (iii) by the degree of compression of following formula definition in 0～18% scope, (iv) this particulate water-absorbing agent of 0.5g is scattered in 20 ℃ of normal saline solutions of 50ml, the surface tension of crossing the supernatant that obtains after 4 minutes is more than or equal to 55mN/m.

The degree of compression (%)=(P-A)/P * 100

Wherein, P is the compact volume density of particulate water-absorbing agent, and A is the bulking volume density of particulate water-absorbing agent.

In addition, the insertion merit that particulate water-absorbing agent of the present invention is preferably the workload of insertion parts when the stratum granulosum of above-mentioned particulate water-absorbing agent is inserted into the 20mm degree of depth is more than or equal to 0g weight * mm and smaller or equal to 75,000g weight * mm.

An object lesson of particulate water-absorbing agent of the present invention is the particulate water-absorbing agent that also contains the lubricant of surfactant or coccoid.

In addition, particulate water-absorbing agent of the present invention preferably is set to, and the absorptivity of this absorbent under the pressurized state of 2.03kPa is more than or equal to 20g/g.

Particulate water-absorbing agent of the present invention preferably is set to, and the absorptivity under the pressurized state of 4.83kPa is more than or equal to 17g/g.

In addition, particulate water-absorbing agent of the present invention preferably is set to, and its physiological saline flow conductivity (salineFlow conductivity) is more than or equal to 20 (10 (SFC) ^-7Cm ³Sg ^-1).

According to above-mentioned setting, can provide following particulate water-absorbing agent: the frictional force between the coccoid particle under the drying regime is little, can prevent retardance or bonding under the sucting wet state, is difficult for causing adhering to device, has good coccoid flowability.Therefore can avoid manufacturing installation to stop or being used for the obstruction of pipeline etc. of the carrying of particulate water-absorbing agent because of overload.And, can alleviate the operation infringement that causes because of the impulsive force of machinery etc., and reduce coccoid and stir power and pneumatic conveying energy needed.In addition, mobile increase makes for example can shorten to move on to the bucket or from bucket from container and loads the needed time to container, thereby can improve operational efficient.

In addition, because the frictional force between the coccoid particle is little, and volume density increases, and makes the amount that container loaded that can improve equal volume, therefore can lower the amount of the particulate water-absorbing agent that transportation (carrying) expense or increase store to bin etc.

And, the problem high and the capillary reduction of difficult generation absorption liquid when absorption liquids such as particulate water-absorbing agent and urine contacts because of the absorbent properties of the absorptivity under the pressurized state etc., make absorbing articles to return quantitative change little, thereby the excellent absorption article can be provided.

Above-mentioned coccoid lubricant preferably has the alkyl of the carbon atom more than 7 or 7 on the side chain, and the quality average particulate diameter is more than or equal to 0.01 μ m and smaller or equal to the polymeric additive of 100 μ m.

In addition, the addition of above-mentioned polymeric additive is preferably, with respect to above-mentioned water-absorbing resins 100 weight %, in the scope of 0.01 weight % to 10 weight %.

In addition, above-mentioned polymeric additive is preferably, and has the monomer of the carbon atom more than 7 or 7 by the alkyl on its side chain, with respect to (being total to) polymer as polymeric additive, is polymerized with the amount (being total to) of 15 weight % to 100 weight %.

In addition, above-mentioned polymeric additive is preferably, and is added into the surface of above-mentioned water-absorbing resins with the state of solution or suspension.

In addition, above-mentioned polymeric additive is preferably, and is the powder of 0.01 μ m to 100 μ m with the quality average particulate diameter, is added into the surface of above-mentioned water-absorbing resins.

According to above-mentioned setting,, can provide the particulate water-absorbing agent that under sucting wet state, also has good flowability even make even the frictional force between the coccoid particle is also very little under sucting wet state.

In addition, the addition of above-mentioned surfactant is preferably, with respect to above-mentioned water-absorbing resins 100 weight portions, in the scope of 0.0005 weight portion to 0.012 weight portion.

In addition, above-mentioned surfactant is preferably, and HLB is 8～18 nonionic surfactant.

According to above-mentioned setting, by using all surfactants in above-mentioned scope of its addition and HLB, then can reduce the frictional force between the coccoid particle, and prevent the capillary reduction of absorption liquid, the feasible reduction that can prevent the water absorption character of particulate water-absorbing agent.

In addition, for solving above-mentioned problem, the feature of particulate water-absorbing agent of the present invention is, contains the lubricant (except that metallic soap) of water-absorbing resins and coccoid, with respect to above-mentioned water-absorbing resins, wherein contains the above-mentioned lubricant of 0.0001 weight %～0.1 weight %.

According to above-mentioned setting, the flowability and the volume density of particulate water-absorbing agent of the present invention similarly are increased, and can obtain the not impaired particulate water-absorbing agent of water absorption character.

Particulate water-absorbing agent of the present invention preferably is set to, and bulking volume density is more than or equal to 0.7g/ml.

Particulate water-absorbing agent of the present invention preferably is set to, and above-mentioned lubricant is added in the water-absorbing resins coccoid.

In addition, particulate water-absorbing agent of the present invention preferably is set to, above-mentioned water-absorbing resins has at least a in the following shape: amorphous broken shape particle, the amorphous broken shape particle of graininess, the spherical particle of graininess, the oval particle of graininess, or its mixture.

In addition, for solving above-mentioned problem, absorbent commodity of the present invention contains any one in the above-mentioned particulate water-absorbing agent.

For solving above-mentioned problem, the feature of the manufacture method of particulate water-absorbing agent of the present invention is, comprise the steps: to add (A) surface crosslinking agent that contains as necessary composition to water-absorbing resins with cross-linked structure, (B) surface conditioning agent of the lubricant of surfactant or coccoid, with the cross-linking of water-absorbing resin surface, wherein, the addition of the lubricant of this surfactant or coccoid is, relative these water-absorbing resins 100 weight portions, in the scope of 0.0005～0.012 weight portion, and this particulate water-absorbing agent of 0.5g is scattered in 20 ℃ of normal saline solutions of 50ml, and the surface tension of crossing resulting supernatant after 4 minutes is more than or equal to 55mN/m.

In addition, it is 200～600 μ m that surface-crosslinked preceding water-absorbing resins is preferably (i) quality average particulate diameter (D50), and (ii) the logstandard deviation of size distribution (σ ζ) is 0.25～0.45.

In addition, this particulate water-absorbing agent is preferably, its by the degree of compression of following formula definition in 0～18% scope,

The degree of compression (%)=(P-A)/P * 100

Wherein, P is the compact volume density of particulate water-absorbing agent, and A is the bulking volume density of particulate water-absorbing agent.

Other purposes of the present invention, feature and advantage will prove absolutely by following record.To describe the specific embodiment of the invention by the reference the description of the drawings below.

Description of drawings

Fig. 1 is the generalized section of the structure of the device of the absorptivity under the mensuration pressurized state that uses in the embodiments of the invention.

The schematic perspective view of structure that Fig. 2 inserts distance for the mensuration particulate water-absorbing agent that uses among the present invention relevant and inserts the device of merit.

Fig. 3 be the said determination device compression set want portion's front view.

Fig. 4 is insertion probe (insertion parts) front view of said determination device.

Load required when Fig. 5 inserts stratum granulosum for inserting probe (insertion parts) among embodiment of expression is with the tendency chart that respectively inserts variable in distance that inserts probe.

Fig. 6 is the generalized section of the structure of the device of the flow conductivity (SFC) of the mensuration physiological saline that uses in the embodiments of the invention.

Fig. 7 (a) is the profile of the device of the mensuration bulking volume density used in the embodiments of the invention and flow velocity.

Fig. 7 (b) is the plane of the device of the mensuration bulking volume density used in the embodiments of the invention and flow velocity.

The specific embodiment

Absorbent article to water-absorbing resins of the present invention and particulate water-absorbing agent and this particulate water-absorbing agent of use is elaborated below.The present invention includes various changes and replacement form, below the described specific embodiment only be the purpose of example.Be appreciated that the present invention is not limited to the disclosed specific embodiment, but contain the interior various variations of the spirit and scope of the invention that appended claim limits.

By following specific embodiment 1-3 the present invention is described.Particulate water-absorbing agent of the present invention preferably contains water-absorbing resins and coccoid lubricant or surfactant, but is not limited to these.This particulate water-absorbing agent obtains by following variety of way: by adding polymeric additive and Powdered lubricant, the alkyl on the side chain in the molecule of described Powdered lubricant contains (specific embodiment 1) of the carbon atom more than 7 or 7; By add with (A) surface crosslinking agent and (B) surfactant serve as must composition surface conditioning agent, and heat gains to carry out surface-crosslinked processing (specific embodiment 2); By adding coccoid lubricant (specific embodiment 3).

Below, lubricant, particulate water-absorbing agent and the absorbent article of water-absorbing resins, polymeric additive, surfactant, coccoid carried out specific description.

Particulate water-absorbing agent of the present invention is used to absorb the aqueous solution of water, the various aqueous solution and urine and blood etc., in the contained whole compositions of this particulate water-absorbing agent, pure resin content partly as the contained water-absorbing resins of main component is, solid shape part with respect to particulate water-absorbing agent, normally 70 weight % (quality %) are to 100 weight %, preferably 80 weight % (quality %) most preferably are that 90 weight % (quality %) are to 100 weight % to 100 weight %.This particulate water-absorbing agent contains water-absorbing resins and side chain has the polymeric additive of the alkyl of 7 or 7 above carbon atoms, and can also contain other compound (hereinafter referred to as other composition) except that this water-absorbing resins and this polymeric additive.

Below to the contained water-absorbing resins of particulate water-absorbing agent of the present invention, polymeric additive, and particulate water-absorbing agent, the parameter in the time of bringing into play the flowability etc. of good absorbent properties and coccoid, use the absorbing articles of above-mentioned particulate water-absorbing agent to be elaborated.In specification of the present invention, " quality " is equivalent with " weight " in addition.

(I) water-absorbing resins

In order to reach above-mentioned purpose, (water-absorbing resins with cross-linked polymeric structure gets final product must to use the water-absorbing resins that the unsaturated monomer cross-linked polymeric that contains acidic group and/or its salt forms among the present invention, also can be to contain after the polymerization of unsaturated monomers of acidic group and/or its salt, the self-crosslinking during by crosslinking agent or polymerization carries out the water-absorbing resins that cross-linking reaction obtains).

Water-absorbing resins of the present invention be meant have water-swellable, water-insoluble and can form the cross-linked polymer of hydrogel.For example, water-swellable is meant, water-absorbing resins is immersed in the ion exchange water, its absorb liquid, aqueous amount than himself weight greatly at least 5 times or more, preferably 50 times～1000 times.In addition, water-insoluble is meant, the content of the uncrosslinked water soluble ingredient (water soluble polymer) in the water-absorbing resins is 50 weight % or still less (be limited to 0% down) preferably, be more preferably 25 weight % or still less, more preferably 20 weight % or still less, be more preferably 15 weight % or still less, most preferably be 10 weight % or still less.The Determination on content method of above-mentioned water soluble composition will be described in embodiment described later.

In addition, above-mentioned cross-linked polymer is meant to obtaining the polymer that polymer inside that good absorption characteristic obtains by the polymerization unsaturated monomer has cross-linked structure (hereinafter referred to as the internal crosslinking structure).And above-mentioned water-absorbing resins can be implemented surface-crosslinked processing, so that form cross-linked structure at this water-absorbing resins near surface, also can not implement this surface-crosslinked processing.Wherein, for obtaining good absorption characteristic, preferably implement surface-crosslinked processing.

The example of the water-absorbing resins that is made of above-mentioned cross-linked polymer is a kind of in the following substances, two or more: the acrylic acid polymer of part neutralization, the starch of hydrolysis-acrylonitrile grafting polymer, the starch of starch-acrylic acid-grafted polymer or neutralization-acrylic acid-grafted polymer, crosslinked carboxymethyl cellulose, the vinyl acetate-acrylic copolymer of saponification, the acrylonitrile copolymer of hydrolysis or the acrylamide copolymer of hydrolysis, or crosslinked acrylonitrile copolymer or crosslinked acrylamide copolymer, the carboxylic cross-linking polyvinyl alcohol of modification, crosslinked cationic monomer, 2-acrylamide-2-methyl propane sulfonic acid and acrylic acid cross-linked polymer, crosslinked isobutene-copolymer-maleic anhydride etc.Wherein preferably uses the acrylic acid polymer that neutralizes by polymerization and/or the crosslinked part that obtains as the unsaturated monomer of main component with acrylic acid and/or its salt (acrylic acid of neutralization).

The water-absorbing resins that is made of above-mentioned cross-linked polymer is to obtain by polymerization and/or crosslinked unsaturated monomer, implements surface-crosslinked processing as required.Below explanation is used to make unsaturated monomer, cross-linking monomer, the polymerization initiator of water-absorbing resins, the manufacture method of water-absorbing resins.

＜unsaturated monomer 〉

For obtaining the unsaturated monomer that the contained water-absorbing resins of particulate water-absorbing agent of the present invention uses so long as can obtain desired cross-linked polymer and get final product.

For example, when above-mentioned cross-linked polymer is the acrylate copolymer of part neutralization, preferably use acrylic acid and/or its salt (acrylic acid of neutralization), and acrylic acid and/or its salt and other monomers are used in combination as copolymer composition as main component.Therefore, the water-absorbing resins that obtains as end-product not only has water absorption character, also has other characteristic such as antibiotic or deodorizing, and can obtain water-absorbing resins with lower price.

As copolymer composition, the example of above-mentioned other unsaturated monomer comprises water dissolvable or water-insoluble unsaturated monomer, and for example β-acryloyl ethylene lactic acid, methacrylic acid, maleic acid (or maleic anhydride), fumaric acid, butenoic acid, itaconic acid, vinyl sulfonic acid, 2-(methyl) acrylamide-2-methyl propane sulfonic acid, (methyl) acryloyl group alcoxyl sulfonic acid etc. contain the monomer of acidic group and their alkali metal salt, ammonium salt, alkanamine; N-ethene-2-Pyrrolidone, N-ethene acetamide, (methyl) acrylamide, N-isopropyl (methyl) acrylamide, N, N-dimethyl (methyl) acrylamide, 2-hydroxyethyl (methyl) acrylate, methoxy poly (ethylene glycol) (methyl) acrylate, polyethylene glycol (methyl) acrylate, isobutene, lauryl (methyl) acrylate etc.These monomers can be used alone, and also the suitable monomer more than 2 kinds can be mixed and use.Above-mentioned monomer of the present invention can be used as copolymer composition.

And the unsaturated monomer that contains acidic group when use is during as above-mentioned unsaturated monomer and other unsaturated monomer, and the salt of this unsaturated monomer can use alkali metal salt, alkali salt or ammonium salt, preferably uses alkali metal salt.Wherein, be preferably at least and must use sodium salt or sylvite, this is that they are harmless, and the use of sodium salt and sylvite can make the water-absorbing resins of acquisition have more performance because industrial being easy to of sodium salt and sylvite obtains.。

When share in addition other unsaturated monomer of aforesaid propylene acid (salt), with respect to for obtaining the total mole number of all unsaturated monomers that water-absorbing resins uses, the monomer except that acrylic acid (salt) preferably 0～30 mole of %, be more preferably 0～10 mole of %, most preferably be that the ratio of 0～5 mole of % uses.In other words, relatively for obtaining the total mole number of all unsaturated monomers that water-absorbing resins uses, as the total mole number of the acrylic acid of Main Ingredients and Appearance and salt thereof preferably 70～100 moles of %, be more preferably 90～100 moles of %, most preferably be 95～100 moles of %.

In addition, the unsaturated monomer that acrylic acid etc. contain acidic group is about neutrality according to character and pH value, and preferred acidic group is neutralized.The neutralization ratio of acidic group (all mole % of the acidic group that is neutralized in the acidic groups) normally 20～100 moles of %, be more preferably 30～95 moles of %, most preferably be 40～80 moles of %.Acidic group can be by monomer, polymer or the neutralization of its bond.

＜cross-linking monomer (internal crosslinking agent) 〉

Water-absorbing resins of the present invention is the cross-linked polymer with internal crosslinking structure.When water-absorbing resins has water-insoluble and water-swellable, can think to have the internal crosslinking structure.Therefore, the internal crosslinking of water-absorbing resins structure can obtain by making the unsaturated monomer self-crosslinking, and does not use cross-linking monomer.But preferably with above-mentioned unsaturated monomer and cross-linking monomer copolymerization or reaction and obtain water-absorbing resins.At this, have 2 or more a plurality of polymerisable unsaturated group or 2 or more a plurality of reactive groups in the molecule as the cross-linking monomer of internal crosslinking agent.

The example of above-mentioned internal crosslinking agent comprises: N, N '-di-2-ethylhexylphosphine oxide (methyl) acrylamide, (gathering) ethylene glycol bisthioglycolate (methyl) acrylate, (gathering) propane diols two (methyl) acrylate, trihydroxy methyl the third three (methyl) acrylate, glycerine three (methyl) acrylate, glycerine acrylate acrylate, ethylene oxide sex change trihydroxy methyl the third three (methyl) acrylate, own (methyl) acrylate of pentaerythrite, three acrylic cyanates, three acrylic isocyanates, three acrylic phosphatide, triallylamine, poly-(methyl) allyloxy alkane, (gathering) ethylene glycol bisthioglycolate is the oxygen propyl ether also, glycerine two is gone back the oxygen propyl ether, ethylene glycol, polyethylene glycol, propane diols, glycerine, pentaerythrite, ethylenediamine, ethylene carbonate, the trimethylene carbonic ester, poly-Ethylenimine, oxygen propyl group (methyl) acrylate etc. also.

Above-mentioned internal crosslinking agent can use separately, also suitable mixing more than 2 kinds can be used.In addition, above-mentioned crosslinking agent can once all be added, also can separately add when reaction system adds.When the internal crosslinking agent that uses more than a kind or 2 kinds, consider the water absorption character of the particulate water-absorbing agent that finally obtains etc., must use cross-linking monomer during preferred polymeric with at least 2 polymerisable unsaturated groups.

Viewpoint from the superperformance that obtains water-absorbing resins, the use amount of above-mentioned internal crosslinking agent, with respect to for obtaining the total mole number (not comprising crosslinking agent) of the unsaturated monomer that water-absorbing resins uses, preferably 0.001～2 mole of %, more preferably 0.005～0.5 mole of %, be more preferably 0.01～0.2 mole of %, most preferably be in the scope of 0.03～0.15 mole of %.The use amount of above-mentioned internal crosslinking agent be less than 0.001 mole of % or during greater than 2 moles of %, have can't obtain the sufficient water absorption character of water-absorbing resins may, so unsatisfactory.

State internal crosslinking agent in the use to polymer is inner when importing crosslinked configuration, can be before the polymerization of above-mentioned unsaturated monomer or in the polymerization or after the polymerization with above-mentioned internal crosslinking agent, or add in reaction system in unsaturated monomer or the polymer and back.

＜polymerization initiator 〉

For obtaining water-absorbing resins of the present invention, when the above-mentioned unsaturated monomer of polymerization, preferably use polymerization initiator.Operable polymerization initiator can be free polymerization initiator, for example potassium peroxydisulfate, ammonium persulfate, sodium peroxydisulfate, peracetic acid potassium, peracetic acid sodium, potassium percarbonate, SODIUM PERCARBONATE, TBHP, hydrogen peroxide, 2,2 '-azo (2-amidine propane) dihydrochloride, or Photoepolymerizationinitiater initiater, for example 2-hydroxy-2-methyl-1-phenyl-1-acetone.

From the aspect of substance characteristics, the use amount of above-mentioned polymerization initiator, with respect to for obtaining the employed whole unsaturated monomer total mole numbers of water-absorbing resins, normally 0.001～2 mole of %, 0.01～0.1 mole of % preferably.When above-mentioned polymerization initiator was less than 0.001 mole of %, it is many and not ideal that unreacted remaining monomer becomes.On the other hand, when polymerization initiator surpassed 2 moles of %, it is difficult that the control of polymerization becomes, so also undesirable.

＜polymerization 〉

For obtaining water-absorbing resins used in the present invention, when each above-mentioned monomer of polymerization (unsaturated monomer, other unsaturated monomer, cross-linking monomer), can carry out aqueous solution polymerization, anti-phase suspension polymerisation, bulk polymerization or precipitation polymerization etc.But consider that from the easness aspect of control performance of water-absorbing resins or polymerization and from the absorption characteristic aspect of swelling gel preferred polymerization is to use the aqueous solution polymerization or the anti-phase suspension polymerisation of the aqueous solution of above-mentioned monomer.

When using the aqueous solution of above-mentioned monomer, monomer concentration in this aqueous solution (hereinafter referred to as monomer solution) depends on the temperature of the aqueous solution and the type of monomer, do not have special restriction, but normally 10～80 weight %, preferably 10～70 weight %, be more preferably in the scope of 20～60 weight %.In addition, when carrying out above-mentioned aqueous solution polymerization, can share the solvent beyond the water as required, the solvent that share is not particularly limited.

When above-mentioned polymerization begins, can use polymerization initiator to cause it and begin polymerization.Except that polymerization initiator, also can use radioactivity energy rays such as ultraviolet ray, electron ray, gamma-rays separately, or use with above-mentioned polymerization initiator.Though the temperature of above-mentioned polymerisation depends on the kind of employed polymerization initiator, the temperature in the polymerization is preferably 15～130 ℃, 20～120 ℃ scope more preferably.When reaction temperature during not in above-mentioned scope, the self-crosslinking reaction that increases or carry out transition of the residual monomer of the water-absorbing resins that obtained can take place, may cause the decline of the water absorbing properties of water-absorbing resins, so unsatisfactory.

Anti-phase suspension polymerisation is meant monomer solution is suspended in polymerization in the hydrophobic organic solvent with graininess, for example anti-phase suspension polymerisation put down in writing of United States Patent (USP) 4093776, United States Patent (USP) 4367323, United States Patent (USP) 4446261, United States Patent (USP) 4683274, United States Patent (USP) 5244735.

Aqueous solution polymerization is meant and does not use dispersion solvent, and the method for using the polymerization single polymerization monomer aqueous solution to carry out polymerization, for example aqueous solution polymerization put down in writing of United States Patent (USP) 4625001, United States Patent (USP) 4873299, United States Patent (USP) 4286082, United States Patent (USP) 4973632, United States Patent (USP) 4985518, United States Patent (USP) 5124416, United States Patent (USP) 5250640, United States Patent (USP) 5264495, United States Patent (USP) 5145906, United States Patent (USP) 5380808 or European patent 0811636, European patent 0955086, European patent 0922717.The monomer and the polymerization initiator that are disclosed in these United States Patent (USP)s or the European patent also are applicable to the present invention.

＜dry processing the

By the polymer that above-mentioned polymerization polymerization single polymerization monomer obtains, normally the cross-linked polymer of aqueous gel shape crosslinked polymer form carries out drying as required and handles or powder essence.The powder Triton is everlasting and is carried out before or after dry the processing.

In addition, drying method can be adopted as the moisture content that reaches required and the heat drying that carries out, heated-air drying, drying under reduced pressure, infrared drying, microwave drying, by dewatering, use the various methods of the high humidity drying etc. of high-temperature vapor with hydrophobicity organic solution azeotropic, be not particularly limited.When drying is treated to heated-air drying, usually 60 ℃～250 ℃, preferably 100 ℃～220 ℃, be more preferably 120 ℃～200 ℃ scope (hot blast temperature) and carry out.Drying time is relevant with the kind of surface area, moisture content and the dry machine of polymer, sets drying time according to the water content that will reach.For example, drying time is as long as suitably select 1 minute～5 minutes scope.

The moisture content of the water-absorbing resins that dry back obtains among the present invention (contained amount of moisture in water-absorbing resins or the particulate water-absorbing agent, by with the water-absorbing resins of equivalent 180 ℃ of dryings 3 hours, the amount that reduce dry back is represented with respect to the ratio of the water-absorbing resins before dry) be not particularly limited, for obtaining the better substance characteristics that the present invention is the particulate water-absorbing agent of main component with this water-absorbing resins, preferred control moisture content makes polymer also be particle (powder) shape of flowable in normal temperature.That is, above-mentioned particulate water-absorbing agent normally moisture content be the pulverulence of 0～30 weight %, preferably 0.2～30 weight % pulverulence, be more preferably the pulverulence of 0～20 weight %, be more preferably the pulverulence of 0～15 weight %, especially preferably pulverulence, the special preferably pulverulence of 0.5～10 weight % of 0.3～15 weight % again.Preferably handle the acquisition water-absorbing resins, to obtain particulate water-absorbing agent with the moisture content in the above-mentioned scope by aqueous gel shape cross-linked polymer being carried out drying.If moisture content height then flowability will step-down, this to make always bring obstacle and have water-absorbing resins can't be by powder essence, can't obtain specific problems such as size distribution.

When using above-mentioned anti-phase suspension polymerization to carry out polymerization, usually can carry out drying and not carry out powder essence the aqueous gel shape cross-linked polymer of the intact back of polymerisation gained is as described below: aqueous gel shape cross-linked polymer is scattered in the organic solvent such as the hydrocarbon of hexane, azeotropic dehydration then, so that the moisture content of polymer is for smaller or equal to 40 weight % (be limited to down 0 weight %, preferably 5 weight %), be preferably smaller or equal to 30 weight %, by decant or evaporation organic solvent is separated then, and carry out drying as required and handle.In addition, in polymerization or after the polymerization, in water-absorbing resins of the present invention, add polymeric additive and mixing.After polymerization, add and when mixing polymeric additive, can be before dry, dry back or the pure back of powder add and mixing.

＜surface-crosslinked processing (being also referred to as surface-crosslinked) 〉

The employed water-absorbing resins of particulate water-absorbing agent of the present invention has preferably carried out above-mentioned cross-linked polymeric and dry the processing, carry out powder essence as required after, carry out further crosslinking Treatment (secondary cross-linking) to its near surface again.Water-absorbing resins of the present invention is meant two kinds of the resin that has carried out surface-crosslinked processing and the resin that do not carry out surface-crosslinked processing.

Being used for above-mentioned surface-crosslinked crosslinking agent has a variety of, in order to make water-absorbing resins obtain better absorption properties, generally use following crosslinking agent: multivalence alcoholic compound, epoxide, multivalence amines or itself and the condensation product, oxazoline compound of halogenation epoxide, single, double Huo Ju oxazolidone compound, multivalent metal salt, alkyl carbonate compound etc.

The operable surface crosslinking agent of the present invention specifically has disclosed materials such as United States Patent (USP) 6228930,6071976,6254990.For example, monoethylene glycol, diethylene glycol, triethylene glycol, TEG or polyethylene glycol, single propane diols, 1, ammediol, DPG, 2,3,4-trimethyl-1,3-pentanediol, polypropylene glycol, glycerine, polyglycereol, 2-butyl-1,4-glycol, 1,4-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexylene glycol, 1, the multivalence alcoholic compound of 2-cyclohexyl dimethanol, D-sorbite etc.; The epoxide of ethylene glycol bisthioglycolate glycidyl ethers or epoxy prapanol etc.; Ethylenediamine, the multivalence amines of Diethylenetriamine, trien, tetraethyl amylamine, penta ethylhexylamine, poly-Ethylenimine, polyamides base polyamine etc.; The halogenated epoxide of chloropropylene oxide, epibromohydrin, Alpha-Methyl chloropropylene oxide etc.; The condensation product of above-mentioned multivalence amines and above-mentioned halogenated epoxide; The oxazolidinone compounds of 2-oxazolidone etc.; The alkylene carbonic ester compound of ethylene carbonate etc. etc., but surface crosslinking agent is not limited to this.These surface crosslinking agents can use separately, also two or more suitably can be mixed and use.In order to allow effect of the present invention reach to greatest extent, the preferred use has 2～10 carbon atoms, preferably the multivalence alcohol of 3～8 carbon atoms.

The use amount of surface crosslinking agent depends on the kind of employed surface crosslinking agent or their combination etc., but preferably, with respect to water-absorbing resins 100 weight portions (mass parts), in the scope of 0.001 weight portion～10 weight portions, be more preferably the scope of 0.01 weight portion～5 weight portions.

Above-mentioned surface-crosslinked processing preferably makes water.At this moment, the amount of employed water also depends on the moisture content of the water-absorbing resins of use, preferably with respect to water-absorbing resins 100 weight portions (mass parts), in the scope of 0.5 weight portion～20 weight portions, is more preferably the scope of 0.5 weight portion～10 weight portions.

In addition, replace water also can use the mixed solvent of hydrophilic organic solvent or water and hydrophilic organic solvent.The hydrophilic organic solvent that use this moment or the amount of mixed solvent be water-absorbing resins 100 weight portions (mass parts) relatively preferably, in the scope of 0～10 weight portion, are more preferably the scope of 0～5 weight portion, most preferably are the scope of 0～3 weight portion.

The adding method of above-mentioned surface crosslinking agent can be various, preferably with surface crosslinking agent must be in advance with after water and/or hydrophilic organic solvent mix, again to the water-absorbing resins spraying or drip the method for this aqueous solution, be more preferably the method for spraying.The size of the drop of spraying preferably average diameter is the scope of 0.1～300 μ m, is more preferably the scope of 0.1～200 μ m.

When mixing water-absorbing resins, this surface crosslinking agent, water or hydrophilic organic solvent, for these materials being mixed and fully, employed mixing arrangement is preferably the mixing arrangement with big mixing force.The example of above-mentioned mixing arrangement has cylinder type mixer, double-deck circular cone mixer, high-speed stirred type mixer, V-shape mixer, banding pattern mixer, screw type mixer, both arms mixing machine, the pure type mixing machine of powder, rotary mixer, airflow mixer, vortex agitator, batch mixer, continuous mixer etc.

When the blending surface crosslinking agent, mix before surface-crosslinked side chain have the carbon atom more than 7 or 7 alkyl polymeric additive or can together mix also with surface crosslinking agent and can obtain particulate water-absorbing agent of the present invention.Will be described later about this polymeric additive.In addition when the blending surface crosslinking agent, do not hinder in the effective scope of the present invention the together insoluble microparticle coccoid of mixing water yet.

With after water-absorbing resins mixes, water-absorbing resins preferably carries out heat treated with surface crosslinking agent.The condition of carrying out of above-mentioned heat treated is, preferably 100～250 ℃ of heating-up temperatures (water-absorbing resins temperature or hot solvent temperature), is more preferably 150～250 ℃, preferably 1 minute～2 hours heat time heating time.The example of the preferred compositions of heating-up temperature and heat time heating time is 180 ℃, 0.1～1.5 hour; 200 ℃, 0.1～1 hour.

If water-absorbing resins is when being obtained by anti-phase suspension polymerisation, after azeotropic dehydration centre after polymerization is finished and/or azeotropic dehydration are intact, for example the moisture content of aqueous gel shape cross-linked polymer for smaller or equal to 50 weight %, preferably smaller or equal to 40 weight %, when being more preferably smaller or equal to 30 weight %, by above-mentioned surface crosslinking agent being scattered in the hydrophobic organic solvent that is used in the anti-phase suspension polymerisation and heating, can obtain the water-absorbing resins that the surface is crosslinked processing.

In addition, the mode of other of surface-crosslinked processing of the present invention has: the treatment fluid that will contain the radical polymerization compound makes an addition to after the water-absorbing resins, irradiation radioactivity energy and carry out surface treatment.For example special method of being willing to that 2003-303306 (putting down into application on 15 years (2003) Augusts 27) is put down in writing.Also can in the treatment fluid in this record, add surfactant, and irradiation radioactivity energy and carry out surface treatment.

The mode of other of surface-crosslinked processing of the present invention also has: after interpolation contained the aqueous solution of peroxide radical initiator in water-absorbing resins, the surface-treated method was carried out in heating.For example special fair 7-8883 communique (putting down into bulletin on 7 years (1995) February 1) is put down in writing.

As mentioned above, high fluidity and high volume density when obtaining moisture absorption are implemented surface-treated water-absorbing resins of the present invention as required and preferably are adjusted to specific particle diameter (granularity).

Because of the particle diameter of above-mentioned water-absorbing resins also is applicable to particulate water-absorbing agent described later, specify so omit it at this.In addition, the particle diameter of water-absorbing resins or particulate water-absorbing agent can be according to purpose and its needs, and by adding insoluble microparticle or hydrophilic solvent, preferably water mixes and further granulation adjustment.

Particulate water-absorbing agent of the present invention described later preferably contains lubricant or the surfactant as above-mentioned water-absorbing resins that obtains and coccoid.The lubricant of explanation coccoid is the situation of the polymeric additive of the alkyl of side chain with the carbon atom more than 7 or 7 in the specific embodiment 1.

(II) lubricant of coccoid or surfactant

Embodiment 1

＜polymeric additive 〉

1. the component of polymeric additive

The polymeric additive that can use in the present invention has the macromolecular compound that the monomer of the alkyl of the carbon atom more than 7 or 7 gets for (being total to) polymeric side chains, or to the side chain of macromolecular compound with reaction active groups introduce alkyl with the carbon atom more than 7 or 7 and macromolecular compound.

Above-mentioned alkyl is the hydrocarbon unit that is made of carbon and hydrogen, has the carbon atom more than 7 or 7 in its molecule, no matter its structure is straight chain, side chain, ring-type and is saturated or unsaturated.Can further give the effect of antibacterial characteristics etc. when especially using unsaturated alkyls such as undecenyl.

The monomer that alkyl dangled from the main chain of macromolecular compound when the monomer that side chain has an above-mentioned alkyl was meant polymerization.And the side chain that will not generate in polymerization process among the present invention is considered as side chain.Promptly, the side chain of the polyolefin part of the copolymer of applying high voltage polyolefin (polyethylene, polypropylene etc.) synthetic method is not considered to side chain, and the example of described copolymer comprises: ethylene-acrylic acid copolymer, ethene-copolymer-maleic anhydride, ethylene-vinyl acetate copolymer, propylene-acrylic copolymer, propylene-copolymer-maleic anhydride, propylene-acetate ethylene copolymer.These compounds are because of correct limit polymerization thing structure, so the flowability when improving moisture absorption needs a large amount of additions, so uneconomical.

In the above-mentioned side chain with alkyl institute's carbon atom quantity preferably more than 7 or 7, be more preferably more than 8 or 8, more preferably more than 10 or 10, be more preferably more than 12 or 12 again, most preferably be more than 14 or 14.In addition, though the upper limit of the length of alkyl be not particularly limited, preferably below 50 or 50, be more preferably below 40 or 40, most preferably be below 30 or 30.

In addition, the side chain of employed monomer has the alkyl that contains the carbon atom more than 7 or 7 in the polymeric additive of the present invention, and other side chains can contain polyoxyethylene groups, polyoxypropylene base etc.Therefore, the monomer that side chain has the alkyl of the carbon atom more than 7 or 7 can be water miscible, also can be water-insoluble.

Water-soluble monomer of the present invention (hydrophilic monomer) is meant, is 20 ℃ water to the temperature of 100g, have 1g above, be preferably 5g above, be preferably the monomer that 10g is above, most preferably be the above solubility of 20g again.

Above-mentioned water-insoluble monomer is meant that the temperature to 100g is 20 ℃ a water, have 1g following (being limited to 0g down), be preferably 0.5g following, be preferably the monomer of the following solubility of 0.1g again.

The monomer of the side chain of above-mentioned alkyl with the carbon atom more than 7 or 7 is alcohol or amine with alkyl of the straight or branched of the carbon atom more than 7 or 7 or ring-type, reacts ester or the amide monomer that obtains with carboxylic ethylene unsaturated monomer.The representative of these monomers has (methyl) acrylate and alkylation (methyl) acrylamide, and wherein the example of (methyl) acrylate has: 2-ethyl-hexyl (methyl) acrylate, dodecyl (methyl) acrylate, octadecyl (methyl) acrylate, isooctadecane base (methyl) acrylate, palmityl (methyl) acrylate, myristyl (methyl) acrylate, octyl group (methyl) acrylate, cetyl (methyl) acrylate, isobornyl (methyl) acrylate, hendecene base (methyl) acrylate, oil base (methyl) acrylate; The example of alkylation (methyl) acrylamide has: 2-ethyl-hexyl (methyl) acrylamide, dodecyl (methyl) acrylamide, octadecyl (methyl) acrylamide, isooctadecane base (methyl) acrylamide, palmityl (methyl) acrylamide, myristyl (methyl) acrylamide, octyl group (methyl) acrylamide, cetyl (methyl) acrylamide, isobornyl (methyl) acrylamide, hendecene base (methyl) acrylamide, oil base (methyl) acrylamide.The above-mentioned ester or the acid amides that also comprise the monomer that maleic acid, fumaric acid, crotonic acid, itaconic acid etc. are similar.

Monomer of the present invention also can be that its straight or branched or closed chain are had the ester monomer that the ethylene unsaturated monomers of the carboxylic acid of alkyl of the carbon atom more than 7 or 7 and hydroxyl reacts to each other and obtains.The representative of this class monomer has: the vinyl acetate of sad ethene, octenoic acid ethene, dodecenoic acid ethene, tetradecenoic acid ethene, glycerine palmitic acid ethene, octadecenoic acid ethene, different octadecenoic acid ethene, undecenoic acid ethene, bebeerilene acid ethene, aphthenic acids ethene, linoleic acid ethene, leukotrienes ethene etc.The above-mentioned ester class that also comprises similar monomers such as carboxyl (methyl) acrylate or ethylene glycol (methyl) acrylate in addition.Especially, the compound of unsaturated hydrocarbons base section with alkyl of the carbon atom more than 7 or 7 can the endowing antibacterial energy, endecatylene ethyl glycol (methyl) acrylate etc. is for example arranged, so particularly suitable.

Monomer of the present invention also can be a carboxylic acid that side chain is contained the straight or branched of alkyl of the carbon atom more than 7 or 7 or closed chain and contain the amide monomer that amino ethylene unsaturated monomer reaction obtains.The representative of this class monomer has sad-N-ethernamine, turn sour-the N-ethernamine, laurate-N-ethernamine, tetradecanoic acid-N-ethernamine, palmitic acid-N-ethernamine, stearic acid-N-ethernamine, isostearic acid-N-ethernamine, hendecanoic acid-N-ethernamine, shellfish be than acid-N-ethernamine, aphthenic acids-N-ethernamine, linoleic acid-N-ethernamine, leukotrienes-ethernamine classes such as N-ethernamine.

Monomer of the present invention also can be that side chain is contained halide and the alcohol or the carboxylic acid of the straight or branched of alkyl of the carbon atom more than 7 or 7 or closed chain and contains quaternary ammonium salt monomer, neutralized salt or the amine that amino ethylene unsaturated monomer reaction obtains.The representative of this class monomer has and has heptyl, octyl group, 2-ethylhexyl, nonyl, lauryl, palmityl, stearyl, isostearoyl base, hendecane base, shellfish be than the quaternary ammonium salt of acidic group, naphthyl, oil base, cetyl, isobornyl, neutralized salt, amine etc.For example, dialkyl aminoalkyl (methyl) acrylate, dialkyl aminoalkyl (methyl) acrylamide, vinylamine, allylamine, Ethylenimine.

Monomer of the present invention also can be a alcohol that side chain is contained the straight or branched of alkyl of the carbon atom more than 7 or 7 or closed chain and contain sulfonic group, the ester monomer that the ethylene unsaturated monomer reaction of phosphate obtains, object lesson has by vinyl sulfonic acid, styrene sulfonic acid, the heptyl ester that reactions such as 2-(methyl) acrylamide-2-methyl propane sulfonic acid or (methyl) acrylic alkyl sulfonic acid obtain, monooctyl ester, the 2-Octyl Nitrite, the ninth of the ten Heavenly Stems ester, lauryl, the palm ester, stearate, isostearate, the undecenyl ester, shellfish is compared acid esters, the naphthalene ester, grease, the hexadecane ester, isobornyl thiocyanoacetate etc.

In addition, also can be the alpha-olefins of the straight chain of side chain with alkyl of the carbon atom more than 7 or 7, side chain, closed chain, 1-nonene, 1-decene, 1-octadecylene etc. are for example arranged.These monomers can use separately, the also two or more uses of mixing that can be suitable.

When (being total to) polymerization, the example of polymeric additive comprises that also its side chain has the macromolecular compound of the alkyl that contains the carbon atom more than 7 or 7, and described macromolecular compound is to obtain by reaction active groups such as the carboxyl of alkyl that contains the carbon atom more than 7 or 7 in its molecule and macromolecular compound, amino, hydroxyl, sulfonic group, phosphate are reacted.

That is, the macromolecular compound of reaction active groups that also can be by will having carboxyl, amino, hydroxyl, sulfonic group, phosphate etc. obtains the polymeric additive that side chain has the alkyl of the carbon atom more than 7 or 7 with reactions such as the alcohol with alkyl of the carbon atom of carbon number more than 7 or 7, carboxylic acid, sulfonic acid, amine.

When not having the alkyl of the carbon atom more than 7 or 7 on the side chain of above-mentioned polymeric additive, flowability when water-absorbing resins interpolation polymeric additive resulting granules shape water absorbing agent will be guaranteed sufficient moisture absorption, and the flowability under the drying regime also becomes badly, uses and becomes very difficult.In addition, also can absorb water the surface tension of liquid low, return many etc. the unfavorable places of quantitative change when using disposable diaper or absorber etc.

By (being total to) when polymeric additive is obtained in polymerization, side chain has the consumption of monomer of the alkyl of the carbon atom more than 7 or 7, (being total to) polymer with respect to polymeric additive, preferably to contain amount (being total to) polymerization of 15 quality % to 100 quality %, being more preferably to contain amount (being total to) polymerization of 20 quality % to 85 quality %, most preferably is to contain amount (being total to) polymerization of 20 quality % to 70 quality %.

When (being total to) polymerization, when introducing the macromolecular compound of group with reactivity by the alkyl that will contain the carbon atom more than 7 or 7, conversion repetitive (monomeric unit), (being total to) polymer with respect to polymeric additive, the amount of monomer is 15 quality % to 100 quality % preferably, being more preferably 20 quality % to 85 quality %, most preferably is 20 quality % to 70 quality %.Above-mentioned " conversion of repetitive (monomeric unit) " is meant, the amount of monomer is calculated as follows: when for example the reaction of polyacrylic acid and octadecanol being obtained side chain and having the polymeric additive of octadecyl, gains are considered to the copolymer of acrylic acid and octadecyl acrylate, calculate with the ratio (quality) with respect to the amount of the monomer that contains octadecyl in the copolymer of polymeric additive (octadecane ester).

Side chain has the amount of monomer of alkyl of the carbon atom more than 7 or 7 not when above-mentioned scope, the flowability of particulate water-absorbing agent when improving moisture absorption and under the drying regime, and quantitative change from polymeric additive to water-absorbing resins that add is many, undesirable economically.

The alkyl that the side chain of above-mentioned polymeric additive has the carbon atom more than 7 or 7 gets final product, and in addition can use any monomer.

Specifically can be the monomer of the alkyl of side chain or the monomer of water dissolvable with the carbon atom more than 7 or 7, this class monomer for example has (methyl) acrylic acid, (anhydrous) maleic acid, fumaric acid, butenoic acid, itaconic acid, vinyl sulfonic acid, 2-(methyl) acrylamide-2-methyl propane sulfonic acid, (methyl) acrylic oxygen alkyl sulfonic acid and ester thereof, acid amides, N-ethene-2-Pyrrolidone, N-ethene acetamide, (methyl) acrylamide, N-isopropyl (methyl) acrylamide, N, N-dimethyl (methyl) acrylamide, 2-hydroxyethyl (methyl) acrylate, methoxy poly (ethylene glycol) (methyl) acrylate, polyethylene glycol (methyl) acrylate, isobutene etc.These monomers can use separately, also suitable two or more mixing can be used.

Wherein, hydrophilic/hydrophobic for control particulate water-absorbing agent surface, preferred monomer (being total to) polymerization that not only can have the alkyl of the carbon atom more than 7 or 7 by side chain, also can obtain polymeric additive by (being total to) polymerization of water dissolvable monomer, this class water dissolvable monomer has (methyl) acrylic acid, (methyl) acrylamide, N-ethene-2-Pyrrolidone, 2-hydroxyethyl (methyl) acrylate, methoxy poly (ethylene glycol) (methyl) acrylate, polyethylene glycol (methyl) acrylate.

Above-mentioned polymeric additive preferably obtains by water-insoluble (hydrophobicity) monomer and water-soluble (hydrophily) monomer copolymerization, the quality ratio of water-insoluble monomer and water-soluble monomer is preferably 15: 85～and 85: 15, be preferably 20: 80～80: 20 again, more preferably 20: 80～70: 30, most preferably be 20: 80～60: 40.

The polymeric additive that is obtained by water-soluble and water-insoluble monomer copolymerization is injected towards in the water-absorbing resins, so that can control the degree of the hydrophilic/hydrophobic of particulate water-absorbing agent, thus the flowability the when absorption speed that do not slow down just can be guaranteed moisture absorption.In addition, polymeric additive and water-soluble monomer copolymerization are so that the polymeric additive possess hydrophilic property makes polymeric additive self also have water-swellable or water dissolvable, if when having imported the quaternary ammonium salt as the undecenyl of above-mentioned unsaturated alkyl or ammonia, can give stronger antibiotic property.

In addition, as the employed monomer of the hydrophilic monomer of the above-mentioned polymeric additive that in water-absorbing resins, adds be monomer with carboxyl, have sulfonic monomer, have the monomer of phosphate, when having amino monomer, monomer can be the form of neutralized salt (alkali metal salt, alkali salt, transition metal salt, ammonium salt, halide salts, acylate, phosphate, sulfonate etc.).Be preferably monovalence or multivalent salts, as sodium, potassium, iron, magnesium, silver, zinc, copper, tin etc., especially because of the slaine more than the divalence, can endowing antibacterial and deodorizing effect and more preferably as the slaine of iron, magnesium, silver, zinc, copper, tin etc.The degree of neutralization of preferred slaine is with respect to whole carboxyls, sulfonic group in the above-mentioned polymeric additive, amino molal quantity, be 75 moles of % following (being limited to 0 mole of % down), be preferably again 50 moles of % following, more preferably 25 moles of % following, most preferably be 10 moles below the %.

When above-mentioned polymeric additive added in water-absorbing resins with coccoid state or suspension state, the cross-linking monomer (also claiming crosslinking agent) that has polymerisable unsaturated group more than 2 or the reaction active groups more than 2 in not only above-mentioned monomer but also the molecule can be by copolymerization or reaction each other.This class crosslinking agent concrete example is if any N, N '-di-2-ethylhexylphosphine oxide (methyl) acrylamide, (gathering) ethylene glycol bisthioglycolate (methyl) acrylate, (gathering) propane diols two (methyl) acrylate, trihydroxy methyl the third three (methyl) acrylate, glycerine three (methyl) acrylate, glycerine acrylate acrylate, ethylene oxide sex change trihydroxy methyl the third three (methyl) acrylate, own (methyl) acrylate of pentaerythrite, three acrylic cyanates, three acrylic isocyanates, three acrylic phosphoric acid fat, triallylamine, poly-(methyl) allyloxy alkane, (gathering) ethylene glycol bisthioglycolate glycidyl ethers, glycerin diglycidyl ether, ethylene glycol, polyethylene glycol, propane diols, glycerine, pentaerythrite, ethylenediamine, ethylene carbonate, the trimethylene carbonic ester, poly-Ethylenimine, glycidyl (methyl) acrylate etc.

These crosslinking agents can use separately, also suitable two kinds can be mixed and use.In addition, with these crosslinking agents can be to the disposable interpolation of reaction system, also can separately add.By these crosslinking agents have or not or the crosslinking agent addition what and can be with the solubility furnishing solubility of the polymeric additive in neutrality or insoluble.The use amount of these crosslinking agents is, with respect to above-mentioned monomer (removing internal crosslinking agent), is preferably 0.001～10 mole of %, and more preferably 0.005～5 mole of % most preferably is 0.01～1 mole of %.

The fusing point of above-mentioned polymeric additive, glass transition point, softening point are preferably 40～250 ℃, more preferably 50～200 ℃, most preferably are 60～150 ℃.If use fusing point etc. are when the polymeric additive below 40 ℃, the mobile step-down when flowability under the drying regime of the particulate water-absorbing agent that water-absorbing resins interpolation polymeric additive obtains or moisture absorption, its usability become abominable and undesirable.Flowability when fusing point, glass transition point, softening point being adjusted to the flowability that not only can keep the coccoid under the normal temperature in the above-mentioned scope, moisture absorption, after sneaking into basic materials such as nonwoven, paper pulp and particulate water-absorbing agent mix, fusing point by being heated to this polymeric additive, glass transition point, more than the softening point, use that mode of heating can fuse basic material and particulate water-absorbing agent each other, immobilization.The fusing point of the polymeric additive that is added, glass transition point or softening point obviously have the tendency of the hot deterioration that basic material and particulate water-absorbing agent take place more than 250 ℃ the time, and be unsatisfactory.

In addition, the molecular weight that above-mentioned macromolecule adds agent is 1,000 to 1,000,000 with weight average molecular weight normally, preferably 5,000 to 1,000,000, more preferably 10,000 to 1,000,000, and most preferably be 50,000 to 1,000,000.The molecular weight of polymeric additive adds polymeric additive and flowability when flowability during the particulate water-absorbing agent that obtains dry, moisture absorption may worsen to water-absorbing resins not when this scope.

When water-absorbing resins added above-mentioned polymeric additive, the form of above-mentioned polymeric additive can be the free position of solution state, suspension state or coccoid state.

When above-mentioned polymeric additive is added to water-absorbing resins with the state of coccoid (microparticle), the particle diameter and the grain shape of polymeric additive coccoid are not particularly limited, common weight (quality) average grain diameter less than water-absorbing resins, be in the scope of 0.01～100 μ m preferably with respect to (upper limit 100 weight %) more than the 90 weight % of the total amount of polymeric additive coccoid, wherein, be in the scope of 0.01～75 μ m more than the 90 weight % with respect to the total amount of polymeric additive coccoid preferably again, more preferably the scope of 5～75 μ m most preferably is in the scope of 5～50 μ m.

In addition, the average grain diameter of polymeric additive coccoid (D50) is preferably 0.01 μ m to 100 μ m, and more preferably 0.01 μ m to 75 μ m most preferably is 0.01 μ m to 50 μ m.Particle diameter distributes and average grain diameter can easily be measured with methods such as known Ku Shi method (Coulter method), radium-shine scattering methods.The coating of particles of being obtained can be granular microparticle, also can be primary granule (individual particle).

The particle diameter of above-mentioned polymeric additive coccoid (microparticle) is not when above-mentioned scope, not only can't improve the flowability when water-absorbing resins adds flowability under the drying regime of the particulate water-absorbing agent that polymeric additive obtains or moisture absorption, and it is the water absorbing properties step-down of particulate water-absorbing agent, thereby undesirable.

The synthetic method of＜polymeric additive 〉

The acquisition methods of above-mentioned polymeric additive has (being total to) polymeric side chains to have the monomer methods of the alkyl of the carbon atom more than 7 or 7, and also oriented side chain with macromolecular compound of reaction active groups such as carboxyl, amino, hydroxyl, sulfonic group, phosphate is introduced the method for the alkyl that contains the carbon atom more than 7 or 7.Consider from easily synthetic aspect, preferably (be total to) monomer methods that polymeric side chains has the alkyl of the carbon atom more than 7 or 7.

With above-mentioned polymeric additive with the state of solution when water-absorbing resins adds, the synthetic method of polymeric additive is just passable as long as carry out polymerization in the soluble solvent of above-mentioned monomer mixture, and preferred solvent has methyl alcohol, ethanol, isopropyl alcohol, oxolane, diethyl ether, carrene, ethyl acetate, toluene, hexane, dimethyl formamide, dimethyl sulfoxide (DMSO), benzene, cyclohexane, water etc.Polymerisation is preferably used the radical polymerization method of the unconjugated free radical that produces by light and heat, can as required chains such as thiodiglycol ester, alkyl hydrosulfide be moved the mixed use of agent.

Initator as radical polymerization can use potassium peroxydisulfate, Ammonium Persulfate 98.5, sodium peroxydisulfate, benzoyl peroxide, hydrogen peroxide, decoyl peroxide, 2,2 '-even bis-isobutyronitrile, peracetic acid sodium, potassium percarbonate, SODIUM PERCARBONATE, t-butylhydroperoxide, 2, free radical polymerization initiators such as 2 '-azo two (2-amidine propane) dihydrochloride, or 2-hydroxy-2-methyl-1-phenyl-propyl group-Photoepolymerizationinitiater initiaters such as 1-ketone.Consider that from the aspect of substance characteristics the use amount of these polymerization initiators is 0.001～2 mole of %, 0.01～1 mole of % (complete relatively amount of monomer) preferably normally.These polymerization initiators are during less than 0.001 mole of %, and the quantitative change of unreacted residual monomer is many, and the control of the polymerization difficulty that becomes when exceeding 2 moles of %, so undesirable.

Polymeric reaction temperature is preferably 0～125 ℃ the scope of adjusting to, preferably 10 minutes～5 hours reaction time.

Monomer concentration in the reaction solution when carrying out polymerisation is the scope of 1～50 weight % preferably, is more preferably 5～30 weight %, most preferably is 10～25 weight %.

When above-mentioned polymeric additive is added in the water-absorbing resins with the state of coccoid or suspension state, the synthetic method of polymeric additive has by the pure method of making of powder, emulsion polymerization or suspension polymerisation and the method for making, precipitation polymerization and the method for making etc.

In above-mentioned emulsion polymerization, the suspension polymerisation, the most surfactants that use of dispersant, when making that adding water absorbing agent that polymeric additive obtains in by water-absorbing resins contacts with the liquid that absorbs water, surfactant can reduce the surface tension of the liquid that absorbs water, so should be noted that use.Most preferred coccoid preparation method is the method for making coccoid by precipitation polymerization.

The synthetic method of precipitation polymerization is the polymerization of being put down in writing as Japanese kokai publication hei 6-199969 communique, Japanese kokai publication hei 3-95204 communique, Japanese kokai publication sho 60-71623 communique or radical polymerization handbook the 264th page (NTS of Co., Ltd. published in 1999).In this polymerization, monomer (single polymers) is dissolvable in water solvent, but the polymer body after the polymerization then is insoluble to solvent, and then separates out as microparticle, just can be easy to obtain microparticle as long as remove solvent.When using this precipitation polymerization method, just can get microparticle, be difficult for taking place the capillary advantage point that the microparticle water absorbing agent reduces absorption liquid so have because of not using surfactant.Therefore, precipitation polymerization method is particularly preferred.

The solvent that carries out precipitation polymerization is because of changing according to employed monomer, thus can't specify, but must select monomer can dissolve the undissolved solvent of the polymer body that generates after the polymerization.The example of representational precipitation polymerization solvent is a hydrophobic organic solvent, for example have 5～10 carbon atoms alkane, as hexane, pentane; The cycloalkane that for example has 5～10 carbon atoms is as cyclohexane, benzene or alkyl substituted benzene; Contain 1～6 carbon atom in toluene, dimethylbenzene, the alkyl and contain the alkyl carboxylic acid ester of 2～6 carbon atom, as ethyl acetate, methyl acetate at carboxylate moiety; Halogenation alkane with 1～2 carbon atom and the halogen more than at least 2, as dichloroethanes, or the like.

Initator as precipitation polymerization can use potassium peroxydisulfate, Ammonium Persulfate 98.5, sodium peroxydisulfate, benzoyl peroxide, hydrogen peroxide, decoyl peroxide, 2,2 '-azodiisobutyronitrile, peracetic acid sodium, potassium percarbonate, SODIUM PERCARBONATE, t-butylperoxide, 2, free radical polymerization initiators such as 2 '-azo two (2-amidine propane) dihydrochloride; Or 2-hydroxy-2-methyl-1-phenyl-propyl group-Photoepolymerizationinitiater initiaters such as 1-ketone.Consider that from the aspect of substance characteristics the use amount of these initators is 0.001～2 mole of %, 0.01～1 mole of % (with respect to whole amount of monomer) preferably normally.These polymerization initiators during less than 0.001 mole of % the quantitative change of unreacted residual monomer many, so and the control of the polymerization difficulty that becomes when exceeding 2 moles of % is undesirable.

Monomer concentration in the reaction solution when carrying out precipitation polymerization is the scope of 1～50 weight % preferably, is more preferably 5～30 weight %, most preferably is 10～25 weight %.When especially under high concentration, carrying out the precipitation polymerization reaction, preferably add molecular weight and be 2000～20000 polyethylene glycol oxide, specifically be to be the amount adding ethylene oxide of 0.5～10 weight % and the copolymer of propylene oxide etc. with respect to monomer, under coexisting state, carry out polymerization.

The precipitation polymerization reaction can generate free radical by heat or redox and carry out polymerisation, and reaction temperature is preferably 0～125 ℃ the scope of adjusting to, preferably 10 minutes～5 hours reaction time.

The sediment that polymerization can be obtained directly adds in the water-absorbing resins, and when preparing as coccoid, carries out drying after removing remaining solvent.Baking temperature will need be adjusted in fusing point, glass branchpoint and below the softening point for the microparticle that prevents to generate becomes integrated, but because of the suitableeest baking temperature depends on employed monomeric species, so can't be specific.Be preferably 30～200 ℃, more preferably 40～150 ℃, most preferably be 50～100 ℃.And dry preferably carries out in reduced pressure, is preferably below the 100mmHg, more preferably below the 50mmHg, most preferably is below the 10mmHg.

After the drying, if the polymeric additive agglutinator then carries out suitable pulverization process, the optimal particle diameter of adjusting to above-mentioned polymeric additive coccoid (microparticle) gets final product.

The polymeric additive that the side chain that the present invention uses has an alkyl of 7 or 7 above carbon atoms can be any one of solution, suspension, coccoid.

Above-mentioned polymeric additive with the state of solution or suspension when water-absorbing resins adds, can use, be scattered in the surface-crosslinked agent solution with above-mentioned polymeric additive dissolving or with pulpous state, so that its method of mixing with water-absorbing resins, wherein said surface crosslinking agent is by mixed surfactant, water and/or employed hydrophilic organic solvent formation in aforesaid surface-crosslinked processing; Perhaps be scattered in water and/or the hydrophilic organic solvent, so that its method of mixing with water-absorbing resins with above-mentioned polymeric additive dissolving or with pulpous state.

As mentioned above, above-mentioned polymeric additive with the state of solution or suspension when water-absorbing resins adds, the addition of the solvent that is formed by water and/or hydrophilic organic solvent depends on the kind and the particle diameter (granularity) of water-absorbing resins, when above-mentioned solvent is water, solid formation with respect to water-absorbing resins divides 100 weight portions, is preferably following, the scope of 1～5 weight portion more preferably of 10 weight portions.When in addition above-mentioned solvent is hydrophilic organic solvent, divide 100 weight portions, be preferably following, the scope of 0.1～5 weight portion more preferably of 10 weight portions with respect to the solid formation of water-absorbing resins.

Dissolving or disperse the concentration of (suspension) polymeric additive in above-mentioned solvent to depend on the kind of employed macromolecular compound or solvent types, viscosity, be not particularly limited, common total amount with respect to polymeric additive and solvent, be 0.001～30 weight %, the preferably scope of 0.01～10 weight %.

Above-mentioned polymeric additive is added when the water-absorbing resins with the state of coccoid, can use, utilize the method that dry-mix process directly mixes the water-absorbing resins and the polymeric additive of coccoid or directly mix after add water again, polymeric additive is fixed in the method on water-absorbing resins surface.

Manufacture method 5 as described later, directly carry out polymerisation on the water-absorbing resins surface, form polymeric additive and when obtaining the manufacture method of particulate water-absorbing agent, also can adopt adding method identical when polymeric additive is added with solution state.In addition, polymerization can utilize light and heat to generate free radical and carry out polymerization, can suitably adopt the polymerization of the polymeric additive described in above-mentioned (II).

When mixing polymeric additive and water-absorbing resins, the coccoid temperature of water absorbing properties resin is generally normal temperature, but be the flowability when obtaining stable water absorption character of particulate water-absorbing agent and moisture absorption, preferably 5～100 ℃ of temperature when macromolecule interpolation profit and water-absorbing resins are mixed with each other are more preferably 20～80 ℃.

Promptly, in the particulate water-absorbing agent of the present invention, flowability when the addition of polymeric additive depends on required moisture absorption and required absorption characteristic, its addition forms branch 100 weight portions admittedly with respect to water-absorbing resins, the scope of 0～30 weight portion preferably, more preferably 0.01～20 weight portion, be more preferably 0.01～10 weight portion, again be more preferably 0.01～5 weight portion, most preferably be 0.01～3 weight portion.When exceeding above-mentioned scope, can't obtain the desired effect of improving of addition, not only uneconomical, the reduction of water absorbing properties self also might take place.

Among the present invention, the device that uses when mixing water-absorbing resins with polymeric additive normally mixes the mixing arrangement of usefulness, for example cylinder type mixer, screw type mixer, spiral shell type extruder, vortex agitator, Nauta mixer, V-shape mixer, ribbon mixer, both arms type mixing machine, flow-type mixer, airflow mixer, rotational circle dish-type mixer, rolling blender, rotary type mixer etc., speed during mixing can be any value, not limit for height speed or low speed.

Embodiment 2

＜surfactant 〉

In the present invention, when surface-crosslinked, adopt the neccessary composition of surfactant, to make particulate water-absorbing agent as surface conditioning agent.Surfactant of the present invention is a possess hydrophilic property part and lipophile (hydrophobicity) part in its molecule, closely adheres to object surfaces by hydrophilic and balance oleophylic, changes its object surfaces characteristic.The example of operable surfactant comprises: anionic surfactant, nonionic surfactant, cationic surfactant, amphoteric surfactant etc.

At the employed water-absorbing resins of 100 weight portions, the amount of described surfactant is 0.0005～0.012 weight portion, and preferably 0.0005～0.001 weight portion is more preferably 0.001～0.0045 weight portion, and the spy is 0.0015～0.004 weight portion preferably.Promptly, when described surfactant is less than 0.0005 weight portion, the improvement of water-absorbing resins aspect its flowability, volume density is insufficient.Otherwise when the amount of described surfactant during greater than 0.012 weight portion, the surface tension of adsorbed liquid descends.Further, can not obtain effect corresponding to the surfactant that is added.This way is uneconomic.

In addition, the HLB (hydrophily-hydrophobicity balance) of the surfactant that the present invention uses is not particularly limited, and preferably 8～18, more preferably 9～17, most preferably be 10～17.HLB when above-mentioned scope, can improve the flowability and the volume density of particulate water-absorbing agent better.

Anion surfactant comprises: the soap of mixed sodium soap soap, semi-harden tallow fatty acids hard soap, odium stearate soap, potassium oleate soap, castor oil SOFT SOAP etc.; The alkyl sulfonic ester salt of sodium laurate, higher alcohol sulfate, NaLS, lauryl triethanolamine etc.; Alkylbenzenesulfonates such as the basic benzene sulfonic acid sodium salt of 12 (alkane); Alkyl naphthyl sulfonate such as alkyl sodium naphthasulfonate; Alkyl sulfo succinates such as dialkyl sodium sulfosuccinate; The alkyl diphenyl ether disulfonate of alkyl diphenyl ether sodium disulfonate etc.; The alkylphosphonic of alkyl phosphoric acid potassium etc.; Polyoxyethylene allylic alkylation (or the alkyl pi-allyl) sulfuric acid of polyethylene glycol oxide bay ether sodium sulfate, polyethylene glycol oxide alkane ether sodium sulfate, polyethylene glycol oxide alkane ether sulfuric acid triethanolamine, polyethylene glycol oxide alkylbenzene ether sodium sulfate etc.; Special reaction type anion surfactant, special carboxylic acid type surfactant; The naphthyl sulfonic acid formalin condensation product of the sodium salt of betanaphthyl sulfonic acid formalin condensation product, the sodium salt of special aromatic sulphonic acid formalin condensation product etc.; Special many carboxyls type high molecular surfactant; Polyethylene glycol oxide alkyl phosphate etc.

Nonionic surfactant comprises: the polyethylene oxide alkyl ethers of polyethylene glycol oxide bay ether, polyethylene glycol oxide cetyl ether, polyethylene glycol oxide stearoyl ether, polyethylene glycol oxide oil alkene ether, the senior alcohol ether of polyethylene glycol oxide etc.; Polyethylene glycol oxide alkyl aryl ethers such as polyethylene glycol oxide nonyl phenylate; Polyethylene oxide derivatives; The sorbitan fatty acid ester of Span-20, sorbitan monopalmitate, sorbitan list octadecane acid esters, sorbitan (three) octadecane acid esters, sorbitan monooleate, sorbitan (three) oleate, Span-83, sorbitan octacosane acid esters etc.; The polyethylene glycol oxide sorbitan fatty acid ester of polyethylene glycol oxide Span-20, polyethylene glycol oxide sorbitan monopalmitate, polyethylene glycol oxide sorbitan list octadecane acid esters, polyethylene glycol oxide sorbitan (three) octadecane acid esters, polyoxyethylene sorbitan monooleate, polyethylene glycol oxide sorbitan (three) oleate etc.; The polyoxyethylene sorbitol fatty acid ester of four oleic acid polyethylene glycol oxide sorbates etc.; The fatty acid glyceride of glyceryl monostearate, glycerin mono-fatty acid ester, self oil-in-water type glyceryl monostearate etc.; The cithrol of polyethylene glycol monolaurate, polyethylene glycol mono stearate, polyglycol distearate, polyethylene glycol monooleate etc.; Polyethylene glycol oxide alkane ether; The polyethylene glycol oxide hardened castor oil; Alkanolamide etc.

Cationic surfactant and two sides surfactant comprise: the alkylamine salt of coconut ammonium acetate, stearic acetate acid amides etc.; The quaternary ammonium salt of lauryl trimethyl ammonium chloride, stearic trimethyl ammonium chloride, cetyl trimethyl ammonium chloride, distearyl dimethyl chlorination amine, alkyl phenyl dimethyl chlorination amine etc.; The alkyltrimethylammonium second lactone of bay betaine, stearic betaine, bay carboxyl methyl hydroxyethyl imidazoline betaine etc.; Amine oxides such as lauryl dimethyl base amine oxide.By using cationic surfactant, making resulting hydrophilic polymer possess antibiotic property becomes possibility.

In addition, as surface-active, it also is possible using the surfactant of fluoridizing.But the surfactant endowing antibacterial of fluoridizing by use.There is the kinds of surface activating agent to use as the spendable surfactant of fluoridizing among the present invention.Described fluorinated surfactant can obtain in the following manner: the hydrogen atom of general surfactant lipophilic group is replaced into fluorine, thereby generates perfluoro alkyl group, and then significantly strengthen its surface-active.

Although surfactant has four kinds of anionic, nonionic, cationic and amphoteric etc., when changing the hydrophilic group of fluorinated surfactant, the fluorocarbon chain of hydrophobic group with same configuration usually.The carbochain of hydrophobic group can be that straight chain also can be a side chain in addition, can use.The representational surfactant of fluoridizing has following material:

Fluoro-alkyl (the carboxylic acid of C2～C10); N-perfluoro octane sulfonyl disodium glutamate; the 3-[fluoroalkane (the oxygen base of C6～C11)]-the 1-alkyl (sodium sulfonate of C3～C4); 3-[ω-fluoro alkynyl (C6～C8)-the N-ethylamino]-the 1-propane sulfonic acid; N-[3-(perfluoro octane sulfamoyl) propyl group]-N, N-dimethyl-N-carboxyl methylene ammonium betaine; fluoro-alkyl (the carboxylic acid of C11～C20); perfluoroalkyl (the carboxylic acid of C7～C13); perfluoro octyl sulfonic acid diethanol amine; perfluoroalkyl (sulfonate (the Li of C4～C12); K; Na); N-propyl group-N-(2-ethoxy) fluoro octyl sulfonamide; perfluoroalkyl (the sulfoamido oxypropyl trimethyl ammonium salt of C6～C10); perfluoroalkyl (C6～C10)-Ethylglycocoll salt (K); phosphoric acid two (N-perfluoro octyl group sulfo group-N-ethyl ammonia ethyl ester); single perfluoro (ethyl phosphonic acid ethyl ester of C6～C16); perfluoroalkyl quaternary ammonium iodide (trade name FC-134; Sumitomo 3M Co., Ltd. makes; the surfactant that cationic is fluoridized); perfluoroalkyl alcoxyl ester (trade name FC-171; Sumitomo 3M Co., Ltd. makes; the surfactant of nonionic fluorinated); perfluoro alkyl sulfonic acid sylvite (trade name FC-95 and FC98; Sumitomo 3M Co., Ltd. makes; the surfactant that anionic property is fluoridized).

Among the present invention, also can use the organic metal surfactant.The organic metal surfactant of the Shi Yonging metal that has Si, Ti, Sn, Zr, Ge etc. at the main chain or the side chain of molecule in the present invention, preferably the main chain at molecule has Si, is more preferably siloxane type surfactants.

That representational organic metal surfactant is published at engineering books (1996), by the " (record in the 34th page of the new edition surfactant handbook of being shown in Jitian, nearly rattan, Da Yuan, the mountain.As metal contained in the organic metal surfactant, can use Sn, Zr, Ge etc. to replace Si or Ti.The surfactant that the present invention uses is not limited to above-mentioned surfactant.

Nonionic surfactant preferably in these surfactants, from the security aspect, wherein sorbitan fatty acid ester, spy polyethylene glycol oxide sorbitan fatty acid ester preferably preferably.

Embodiment 3

＜powdery lubricant 〉

Lubricant is meant between the two sides that is present in mutual slip, work the material of (opposing) effect of reducing friction.Promptly, make between two surfaces easier slip or be difficult for sliding because of the apparent surface's of these materials situation when thing contacts with thing, resistance between them is increased or reduce, and described lubricant is for reducing the material that resistance uses.

The lubricant that the present invention uses is the material that uses for the friction (resistance) that reduces between the water-absorbing resin.With lubricator can obtain bulking volume density and particulate water-absorbing agent that the speed that flows down has improved by making.Flow down speed by raising and can shorten to move on to the hopper or and load the desired time, can improve operating efficiency to container from hopper from container.These effects are also identical in above-mentioned surfactant, are the remarkable results of novel water absorbing agent of the present invention.

In addition, by improving bulking volume density and flowing down speed, the coccoid in the time of can being reduced in the particulate water-absorbing agent manufacturing stirs power or air is carried energy needed.Further, coccoid stirs the reduction of power or air conveying energy needed, can prevent that water-absorbent besin particles is decomposed, and can suppress the increase owing to the fine particle that performance decrease caused, and for example, pressure is to the influence of adsorption capacity.

The operable lubricant of the present invention so long as the lubricant of solid get final product, be not particularly limited, for example can use hydro carbons lubricant, fatty acid lubricant, fatty acid amine series lubricant agent, ester series lubricant agent, pure series lubricant agent, metallic soap lubricant (metal soap lubricant) etc.Wherein, the metallic soap lubricant is preferred, because not only have the effect of lubricant, and has the function of stabilizer metallic soap.In addition, lubricant of the present invention must be a solid down at normal temperature (25 ℃) and normal pressure (0.101MPa).

As the hydro carbons lubricant, can use oligomerization polyethylene etc.The oligomerization polyethylene is meant that molecular weight is about 1500～2000 polyethylene.

As the fatty acid lubricant, so long as it is just passable to work as the aliphatic acid that lubricant uses, be not particularly limited, be 12 (C but preferably use carbon number ₁₂) above aliphatic acid.Object lesson has: laurate, tetradecanoic acid, palmitic acid, stearic acid, arachic acid, mountain Yu acid etc.Wherein preferably use stearic acid, because of it obtains easily.In addition, in these fatty acid lubricants, preferably use the material of microparticle, do not contain the heavy metals such as Fe, Ni of the deterioration that promotes water-absorbing resins, the purifying product of low iodine value, low ester number are preferred.

The fatty acid amine series lubricant agent is the general formula R CONH from fatty acid derived ₂Represented compound.This fatty acid amine series lubricant agent has first order amine (R-CONH ₂), second level amine ((RCO) ₂NH), third level amine ((RCO) ₃N), preferably use first order amine.Concrete example is if any stearylamine, lauryl amine, palmitamide, oily enamine, methylene stearylamine, ethene stearylamine etc.Wherein, because of methylene stearylamine and ethene stearylamine have good compatibility, the transparency, against weather, Abherent, so preferable methyl stearylamine and ethene stearylamine.

Can adopt as the ester series lubricant agent: the polyvalent ester of aliphatic acid, fatty acid polyethylene glycol ester etc.The castor oil (curing castor oil) that preferably vulcanizes in the polyvalent ester of aliphatic acid.In the fatty acid polyethylene glycol ester, glycol monomethyl stearoyl ester preferably.

The alcohol series lubricant agent is the material that the hydrogen of hydro carbons lubricant or fatty acid lubricant is replaced as hydroxyl., be not particularly limited so long as the hydrogen of hydro carbons lubricant or fatty acid lubricant is replaced as hydroxyl gets final product as pure series lubricant agent, for example can use the fatty alcohol of the cetyl alcohol that has a hydroxyl in the molecule or stearyl alcohol etc.; The di-alcohols such as polyethylene glycol that have two hydroxyls in the molecule; Has the polyglycerol of three hydroxyls etc. in the molecule.Polyethylene glycol or polyglycerol also have the effect that prevents static when having the effect of lubricant.

The metallic soap lubricant is by the slaine beyond aliphatic acid (organic acid), petroleum acids, the non-alkali metal salt, and for example, polymer acid constitutes.

The lubricant of coccoid is generally powder shape, its particle diameter is not particularly limited, and less than average footpath of weight (quality) of water-absorbing resins, is 100 μ m or following more than the 90 weight % of powder usually, preferably 50 μ m or following are more preferably 10 μ m or following.

Above-mentioned each lubricant can use separately, also can make up more than 2 kinds and to use, and the method for adding to water-absorbing resins of lubricant is as the foregoing description 1, so omit its explanation.The following describes the addition to water-absorbing resins of lubricant.

By the coccoid lubricant being scattered in the mode in the slurries, the coccoid lubricant is mixed with water-absorbing resins.The concentration of lubricant described in the slurries is suitably selected according to the kind of lubricant and dispersion solvent, the viscosity of slurry, is not particularly limited, and the concentration of lubricant is 0.001～0.1 weight %, the preferably scope of 0.001～0.05 weight % usually.The coccoid temperature of the water-absorbing resins during with mix lubricant is not less than room temperature usually, but for obtaining the stable water absorption character of particulate water-absorbing agent and flow down speed, volume density, preferably 40 ℃ or above, more choosing is to mix under 50 ℃ or the above temperature.

Promptly, lubricant addition in the particulate water-absorbing agent of the present invention can and flow down speed etc. and appropriate change according to desired volume density, preferred lubricant addition is 0.0001～0.1 weight % of relative water-absorbing resin (100 weight %), being more preferably 0.01～0.05 weight %, most preferably is the scope of 0.001～0.01 weight %.The addition of lubricant is when above-mentioned scope, and is very little because of addition, is not endowed the possibility of hydrophobicity and water proofing property, and institute is not so that volume density can make the speed that flows down reduce when increasing.Also can prevent to reduce, lower that coccoid when making particulate water-absorbing agent stirs power and be possible of the minimizing etc. of the required energy of air conveying granular water absorbing agent owing to the mechanicalness impulsive force makes water absorption character.And the addition of lubricant is not only uneconomical when exceeding above-mentioned scope, cause the possibility that reduces water absorption character in addition.

(III) particulate water-absorbing agent

The manufacture method of＜particulate water-absorbing agent 〉

Particulate water-absorbing agent of the present invention preferably contain above-mentioned coccoid lubricant or surfactant and above-mentioned water-absorbing resins, have specific parameter and get final product, its manufacture method is not particularly limited.Being specially can be with any one manufacturing in following 1～6 the method.

During method 1. polymerization water-absorbing resins, the lubricant of coccoid is scattered in the monomer aqueous solution that contains internal crosslinking agent, as required to product implement dryly to handle, grind, surface-crosslinked processing obtain particulate water-absorbing agent.

Method 2. is added coccoid lubricant or surfactant and is mixed in water-absorbing resins, carry out crosslinking Treatment to make particulate water-absorbing agent near surface as required.

Method 3. uses the surface crosslinking agent that contains coccoid lubricant or surfactant that the water-absorbing resins near surface is carried out crosslinking Treatment, makes particulate water-absorbing agent.

Method 4. is carried out crosslinking Treatment at the near surface of water-absorbing resins, and then is mixed coccoid lubricant or surfactant, to obtain described particulate water-absorbing agent when needing the further crosslinked water-absorbing resins in preparation surface.

Method 5. is at the near surface of water-absorbing resins, with side chain have carbon number 7 or 7 above hydrocarbon-based monomer and initator, add surface crosslinking agent as required and mix, carry out polymerisation on the surface of water-absorbing resins and carry out cross-linking reaction as required, directly form big molecular additives, to prepare described particulate water-absorbing agent on the surface of water-absorbing resins.

Method 6. is to the lubricant of water-absorbing resins interpolation coccoid, and the coccoid lubricant is melted in heating while stirring, cools off the coccoid lubricant then, to prepare described particulate water-absorbing agent.

In the middle of above-mentioned 1～6 the manufacture method, as method 1, when the polymerization of water-absorbing resins, can add a kind of monomer aqueous solution, but for additive is evenly adhered on the surface of water-absorbing resins, preferably, add described additive to water-absorbing resins with above-mentioned 2～4,6 manufacture method.

Other composition that＜particulate water-absorbing agent is contained 〉

To water-absorbing resins of the present invention except that adding mentioned component (water-absorbing resins, big molecular additives, internal crosslinker, polymerization initiator, surface crosslinking agent etc.), can add the hydrophilic solvent of polyvalent metal, inorganic powder, water etc. for further obtaining various performances, carry out the granulation of water-absorbing resins.Sometimes can improve logical fluidity, flowability of particulate water-absorbing agent etc. because of adding them.

Spendable polyvalent metal or inorganic powder for example have: international application no is WO2004/JP1007 number (international filing date on February 2nd, 2004), WO2004/JP1294 number (international filing date on February 6th, 2004), WO2004/JP9242 number disclosed materials such as (international filing date on June 3rd, 2004).

Concrete spendable inorganic powder has pair material of waterborne liquid non-activity, for example microparticle of the microparticle of various inorganic compounds, clay mineral etc.This inorganic coccoid is preferably has certain compatibility to glassware for drinking water, and water insoluble or be insoluble in water.Concrete inorganic coccoid comprises: metal oxide, for example silica or titanium oxide etc.; Silicic acid (salt), for example natural zeolite or synthetic zeolite etc.; Kaolin; Talcum powder; Earth; Bentonite etc.Wherein preferred silica and silicic acid (salt); The average grain diameter of particularly using Ku Shi method (Coulter method) to measure is following silica of 200 μ m and silicic acid (salt); In addition, spendable polyvalent metal comprises: the aluminium salt of aluminum sulfate, alum etc.Its use amount depends on the combination of water-absorbing resins and/or particulate water-absorbing agent and inorganic acid, usually relative water-absorbing resins and/or particulate water-absorbing agent 100 weight portions, the content of polyvalent metal is 0.001～10 weight portion, preferably 0～6 weight portion, 0.001～5 weight portion preferably again, being more preferably 0.01～3 weight portion, most preferably is 0.1～1 weight portion.Also with the purpose water absorption character and the granular relevant of particulate water-absorbing agent, but when exceeding above-mentioned scope, can exceed the impact absorption limit of power of big molecular additives, the reduction that for example when being hit power, the prevents water absorption character difficulty that will become.

The mixed method of inorganic powder and water-absorbing resins and/or particulate water-absorbing agent is not particularly limited, and for example can adopt the dry-mix process of mixing between the coccoid, wet mixed method (be dispersed or dissolved in solvent with additive then add) etc.Be preferably dry-mix process when using inorganic powder.And when using polyvalent metal, be preferably the wet mixed method.

The manufacture method of particulate water-absorbing agent of the present invention can also comprise: add hydrophilic macromolecules such as deodorant, antiseptic, spices, blowing agent, pigment, dyestuff, hydrophilicity short fiber, plasticizer, sticker, surfactant, fertilizer, oxidant, reducing agent, water, salt, chelating agent, bactericide, polyethylene glycol, poly-Ethylenimine as required, the hydrophobic macromolecule of alkane etc., the thermoplastic resin of polyethylene or polypropylene etc., the operation of the thermosetting resin of mylar or urea resin etc.The use amount of these additives relative water-absorbing resins 100 weight portions be generally 0～30 weight portion, preferably 0～10 weight portion, be more preferably the scope of 0～1 weight portion.

Particulate water-absorbing agent of the present invention does not lower the surface tension of absorption liquid by adding the lubricant of a spot of surfactant or coccoid, can prevent the decline of the absorption characteristic of particulate water-absorbing agent.The present inventor finds: there is appropriate value (peak value) in the variation of the corresponding coccoid flowability of the addition of the lubricant of surfactant or coccoid, it is slack-off that addition flows down speed during greater than peak value, has when being discharged by hopper (container) bottom to form the phenomenon of building bridge and can't flow down.The interpolation of a spot of surfactant or coccoid lubricant reduces outside the surface tension also significant to the coccoid characteristic.

The characteristic of the particulate water-absorbing agent of present embodiment will be described below.

The particle diameter of＜particulate water-absorbing agent 〉

Particulate water-absorbing agent of the present invention utilizes water-insoluble fine grained or hydrophilic solvent etc. to carry out granulation as required.Preferably, less than 850 μ m to the particle that is not less than 150 μ m account for particulate water-absorbing agent less than 90 weight % (upper limit is 100 weight %); More preferably, the 95 weight % that are no less than particulate water-absorbing agent less than 850 μ m to the particle that is not less than 150 μ m; Also more preferably, the 98 weight % that are no less than particulate water-absorbing agent less than 850 μ m to the particle that is not less than 150 μ m.If carry out granulation, this granulation preferably makes particulate water-absorbing agent have these specified particle diameters.

The mass median diameter of particulate water-absorbing agent is preferably 200～600 μ m, 250～600 μ m more preferably, and also 250～550 μ m more preferably are preferably 250～500 μ m especially, most preferably are 300～500 μ m.

The logstandard deviation value (σ ζ) that the expression particle diameter distributes is preferably the scope 0.25～0.45, and more preferably 0.25～0.42, also more preferably 0.25～0.40, most preferably be scope 0.25～0.38.

When particle diameter exceeds 10 weight % less than the amount of the particle (fine grained) of 150 μ m, can cause following problem, hinder the diffusion to absorber such as blood or urine during suction, make particulate water-absorbing agent more may dissolve because of the area that contacts with air increases when using as absorber; Mobile step-down when absorbing moisture; Because of making operating environment, the dust that produces in the operation of making hygienic materials such as particulate water-absorbing agent or diaper worsens; Increase the generation of problems such as segregation because of wide size distribution, so undesirable.In addition, logstandard deviation may reduce volume density less than 0.25 o'clock.Especially, in the particulate water-absorbing agent of the present invention of the flowability that improves coccoid, when the distribution of particle diameter big or fine grained for a long time, the segregation in hopper or the bag is remarkable, so can cause the difference of quality during introducing in diaper etc.When particle diameter exceeds 10 weight % greater than the particle of 850 μ m, the absorption speed of particulate water-absorbing agent is slack-off, and when being used for absorbent article, sense of touch absorber and skin becomes badly, has foreign body sensation, the user is brought uncomfortable feeling, and therefore this scheme is unfavorable.Have good flowability and volume density and water absorbing properties and do not descend by particle diameter being adjusted to preferable range of the present invention, can easily being obtained, do not have the particulate water-absorbing agent of problems such as segregation.

Can be according to purpose and needs, by insoluble fine grained of interpolation/mixing or hydrophilic solvent (preferably water), further carry out granulation and the particle diameter of particulate water-absorbing agent is adjusted.

The adjustment of granularity can be to carry out dispersin polymerization and granular disintegration is disperseed dry processing the, for example inverse suspension polymerization.Usually, especially when aqueous solution polymerization, product is pulverized, dry back classification is carried out granulation by the product to such classification as required and is waited and recycle, and then is adjusted to specific granularity.

In addition, in order to obtain particulate water-absorbing agent of the present invention, the bulking volume density of water-absorbing resins of the present invention (according to the regulation of JIS K-3362) preferably is adjusted into 0.45～0.85g/ml, and 0.50～0.80g/ml more preferably most preferably is the scope of 0.55～0.80g/ml.

＜add the absorptivity of depressing (Absorbency Against Pressure) 〉

The absorptivity (AAP1) that particulate water-absorbing agent of the present invention was depressed in adding of (under the loading) under the 2.03kPa pressure is equal to or greater than 20g/g, preferably be equal to or greater than 22g/g, more preferably be equal to or greater than 24g/g, also more preferably be equal to or greater than 26g/g, most preferably more than or equal to 28g/g.In addition the upper limit that adds the absorptivity of depressing is not particularly limited, high more good more, but from economic angles such as manufacturing costs, be generally equal to or be lower than 50g/g, be preferably and be equal to or less than 45g/g.

The absorptivity of depressing (AAP2) that adds of (under the loading) is equal to or greater than 17g/g under the 4.83KPa pressure of particulate water-absorbing agent of the present invention, preferably is equal to or greater than 18g/g, more preferably is equal to or greater than 19g/g, most preferably is equal to or greater than 20g/g.In addition, the upper limit that adds the absorptivity of depressing is not particularly limited, high more good more, but for economy such as manufacturing costs, be generally equal to or, preferably be equal to or less than 45g/g less than 50g/g.

It is to be noted that add the loading evaluation that the absorptivity depressed is used 2.03KPa and 4.83KPa here, doing like this is for following imagination, for example diaper be used to accept to lie baby's the heavy burden of position or seat of absorber or absorbent article.Narration adds the assay method of the absorptivity of depressing in an embodiment.

Slamp value during＜moisture absorption 〉

Slamp value during moisture absorption (hereinafter to be referred as the moisture absorption flowability) is the obstruction of particulate water-absorbing agent when being placed on 25 ℃ and 90%RH relative humidity or the index of the evaluation of the flowability of caking property or coccoid.Particulate water-absorbing agent of the present invention does not have obstruction or bonding usually when the hydroscopicity of about 1～25 weight %, and has shown excellent moisture absorption flowability.When particulate water-absorbing agent of the present invention is placed 1 hour under 25 ℃, 90%RH, its moisture absorption slamp value is for being not less than 90 weight % to being no more than 100 weight %, it is above to being no more than 100 weight % to be preferably 95 weight %, more preferably is not less than 98 weight % to being no more than 100 weight %.In the preservation of water-absorbing resins or particulate water-absorbing agent or in making absorbent commodity process such as diaper, perhaps making absorbent article for example during diaper, the decline of the flowability in the time that moisture absorption can being prevented, particulate water-absorbing agent agglomeration of particles or obstruction.The shut-down of the manufacturing installation that causes so can prevent the coccoid of manufacturing installation inside from stopping up.The assay method of the slamp value when narrating moisture absorption in an embodiment.

The shape of＜particulate water-absorbing agent 〉

The shape of particulate water-absorbing agent generally is, Fig. 1 of for example U.S. Patent number 5244735,2 is put down in writing passes through the shape of the primary granule of sphere that anti-phase suspension polymerisation obtains or ellipse or wienerwurst shape (ellipse that part flattens); The shape of the granular disintegration of the primary granule that spherical or oval particle aggregation forms, as NON WOVENS WORLD, in October, 2000-November (75 pages the gathering bead that Fig. 1 put down in writing of marketing technique service company (Marketing Technology Service, Inc.) publish); Also have; the amorphous shape of the crushed product of the aqueous gel shaped polymer that polymerization obtained by monomer solution and the granulated product shape of crushed product; as Fig. 2,3 of U.S. Patent number 5981070,4 shape or NON WOVENS WORLD, the crystal of 75 pages of Fig. 1 of the 10-11 month in 2000.

Particulate water-absorbing agent of the present invention is preferably the shape beyond spherical primary granule and the oval-shaped primary granule; the more preferably granulation thing shape of spheric granules or oval particle; the amorphous shape of the crushed product of the aqueous gel shaped polymer that polymerization obtained by monomer solution; or the granulation thing shape of this crushed product, even the more preferably shape of amorphous shape or granulation product.

Spherical and/or oval-shaped primary granule is not preferably because of for example these shapes and paper pulp and other fibrous material undercompounding in the production of absorbent article, and particulate water-absorbing agent comes off from the absorber that is mixed by particulate water-absorbing agent and fibrous material easily.The water absorbing agent of therefore, use sphere and oval-shaped primary granule form has produced particulate water-absorbing agent and has been difficult for by equally distributed problem in absorber.

Powder fluidity under the＜drying regime 〉

This polymeric additive of the particulate water-absorbing agent that is used for obtaining in the present invention has the high-melting-point more than or equal to room temperature, high glass transition point or high softening-point, therefore under room temperature state, not only when moisture absorption, can also be 0～20 weight % at moisture content, more preferably moisture content is under the drying regime of 0～10 weight %, can reach the high fluidity of powder and the high fluidity under the compaction state.As the index of expression powder fluidity, use the time that flows down (Flowability (450.2-02)) of EDANA (Europe is with promptly abandoning and non-weaving cloth association) regulation etc.Flowing down the time (Flowability) is a kind of evaluation method, (25 ℃, relative humidity 50%RH) at ambient temperature, hopper to regulation adds 100g water-absorbing resins or particulate water-absorbing agent coccoid, measures the powder that added all from time that hopper is discharged.The time that flows down is short more just can judge that better flowability is arranged.Its preferable range is in 20 seconds, more preferably in 17 seconds, most preferably in 14 seconds.

And, in the past,, added inorganic matter to particulate water-absorbing agent usually for ensureing the flowability under the moisture absorption condition.If add inorganic matter, be that intergranular coefficient of friction under the drying regime of 0～20 weight % will uprise (the sliding variation between the particle) especially at moisture content to particulate water-absorbing agent.Therefore, cause air conveyor, oar formula conveyer, the screw conveyer transporting resistance when the conveying granular water absorbing agent to increase.As a result, the obstruction of particulate water-absorbing agent has taken place in process units or the conveyer, its performance reduces, and overload occurs.These situations have caused the shutdown of frequent generation said apparatus.

Especially, amorphous granular (the amorphous crushed product and the granulation product thereof that obtain by the aqueous gel shaped polymer of fragmentation, the granulation product that the agglomeration that is obtained by anti-phase suspension polymerisation is spherical or oval particle is formed) has distorted shape in, cause intergranular coefficient of friction to increase, this makes the mobile variation under the compaction state.

But, because particulate water-absorbing agent of the present invention contains above-mentioned water-absorbing resins and powdery lubricant or surfactant, so even there is above-mentioned amorphous granular, the flowability of particulate water-absorbing agent under compaction state is also high.

Here, the inventor finds, when the flowability under the compaction state of particulate water-absorbing agent is estimated, the result shows that particulate water-absorbing agent has predetermined flowability, even the particulate water-absorbing agent that comprises amorphous granular also handles in process units or conveyer easily, thereby prevented problems such as obstruction.

Promptly, the evaluation method of the flowability under the compaction state is, dark by will vertically inserting 20mm to the particulate water-absorbing agent of compaction state as the probe (metal bar) of insertion parts, estimate to be inserted into the insertion merit (probe insertion work by 20mm insertion, PIW) of 20mm when dark.In this evaluation method, the PIW value that is inserted into 20mm is low more, shows that the coefficient of internal friction of pulverous particulate water-absorbing agent and frictional force are low more, and flowability is high more.

Mobile low under this compaction state of most of water-absorbing resins and particulate water-absorbing agent in the prior art, even can't reach 20mm probe of the present invention and insert distance and (insert distance according to probe of the present invention, PID).

On the contrary, particulate water-absorbing agent of the present invention PIW when probe is inserted into 20mm is very low.Specifically, PIL is not less than 0 grammes per square metre * millimeter to being no more than 75000 grammes per square metre * millimeters, preferably be not less than 0 grammes per square metre * millimeter to being no more than 55000 grammes per square metre * millimeters, more preferably be not less than 0 grammes per square metre * millimeter to being no more than 45000 grammes per square metre * millimeters, even more preferably be not less than 0 grammes per square metre * millimeter to being no more than 35000 grammes per square metre * millimeters, especially preferably be not less than 0 grammes per square metre * millimeter to being no more than 25000 grammes per square metre * millimeters.When PIW exceeded above-mentioned scope, particulate water-absorbing agent had high coefficient of internal friction, had the possibility that causes the problems such as obstruction in the reduction of material performance and process units and the conveyer.

Like this, use above-mentioned evaluation method, select to have the particulate water-absorbing agent of regulation powder fluidity, mobile high particulate water-absorbing agent can be provided reliably.And, because particulate water-absorbing agent of the present invention has good flowability (flowing down the flowability under time, the compaction state), reduced the transporting resistance that air conveyor, oar formula conveyer, the particulate water-absorbing agent air-flow of screw conveyer when conveying are carried, can avoid the obstruction of existing process units that takes place frequently and the particulate water-absorbing agent in the conveyer and install the situation of stopping work owing to overload causes these.And particulate water-absorbing agent also is useful simplifying equipment such as hopper, powder bunker, and these equipment for example use in the manufacture process of the absorber that uses this particulate water-absorbing agent.And the detailed calculated method of PIW is elaborated in the following embodiments.

＜nothing adds the absorptivity of depressing (CRC) 〉

Do not have and to add 30 minutes the absorptivity of sodium-chloride water solution (CRC1) that absorptivity (CRC) expression of depressing need not any pressure absorbs 0.90 weight %.This CRC1 is preferably more than or equals 25g/g, more preferably greater than or equal 28g/g, also more preferably greater than or equal 30g/g.Absorptivity is not in above-mentioned scope the time, and particulate water-absorbing agent does not show high-performance when using in diaper.

And, in the present invention, surface-crosslinkedly can reduce its absorptivity (CRC1), compare with absorptivity (CRC1) before the surface-crosslinked processing, preferably reduce by 95～50%, more preferably 90～60%.Notice that the reduction of absorptivity optionally can be adjusted according to kind, amount, reaction temperature and the time etc. of crosslinking agent.

The arrival rate of＜5 minutes absorptivities 〉

The arrival rate of 5 minutes absorptivities is as illustrated in the following embodiments, be that 5 minutes nothing adds and depresses absorptivity (CRC2) and add the represented parameter of ratio (percentage) of depressing absorptivity (CRC1) with 30 minutes nothing, promptly represent the parameter of the affected degree of absorption speed under the water absorbing agent situation of transforming with additive.Therefore, the arrival rate of 5 minutes absorptivities is high more, and then infiltration rate is fast more, and absorbent properties are good more.The situation that being characterized as of resulting granules shape water absorbing agent of the present invention almost do not have infiltration rate to reduce, the arrival rate of 5 minutes absorptivities is more than or equal to 30% and is less than or equal to 100%, be preferably more than or equal 40% and be less than or equal to 100%, more preferably more than or equal to 50% and be less than or equal to 100%, most preferably be more than or equal to 55% and be less than or equal to 100%.When the arrival rate of 5 minutes absorptivities less than 30% the time, infiltration rate is slow excessively, when this particulate water absorbing agent used in hygienic materials such as diaper, the possibility that troubles such as leakage of urine take place uprised.

＜surface tension 〉

As illustrated in the following embodiments, when surface tension is used to estimate that water-absorbing resins or particulate water-absorbing agent contact with absorption liquid, the capillary reduction degree of absorption liquid.Surface tension reduces amplitude when big, and the amount of returning when using in hygienic materials such as diaper (re-wet: the amount of returning urine that is absorbed by diaper etc.) becomes big, makes the user produce uncomfortable sensation.The feature of resulting granules shape water absorbing agent of the present invention is that surface tension reduction amplitude is little, when measuring with the assay method described in the following embodiment, under 20 ℃ condition determination, preferably has surface tension more than or equal to 50mN/m, more preferably has surface tension more than or equal to 55mN/m, further preferably has surface tension more than or equal to 60mN/m, further preferably have surface tension, most preferably have surface tension more than or equal to 68mN/m more than or equal to 65mN/m.

＜bulking volume density (volume weight) 〉

As illustrated in the following embodiments, and " bulking volume density " (unit: g/ml) expression, in container, fill under the situation of agglomerated particle with a constant volume, represent the value of the quality of whole agglomerated particle, by the quality of per unit capacity.That is, bulking volume density is big more, and the granular mass that occupies in the per unit capacity is big more.And, when the vessel filling particle,, make bulking volume density be lower than " real density (vacuumdensity) " (unit: g/cm of expression particle unit volume quality owing to space parallax owing to have gap (space) between particle ³).For example, the real density of water-absorbing resins in Sodium Polyacrylate is about 1.5～1.7g/cm ³

In particulate water-absorbing agent of the present invention, bulking volume density preferably in the scope of 0.45～0.85g/ml, more preferably 0.50～0.80g/ml, further preferred 0.55～0.80g/ml is in the scope particularly preferably in 0.70～0.80g/ml.

By increasing bulking volume density, for example, can stablize the particulate water-absorbing agent of in container, filling, and can increase its amount.Therefore, can reduce the cost of container, can store a large amount of particulate water-absorbing agents, and can with storage tank for example hopper carry this particulate water-absorbing agent.And, use particulate water-absorbing agent and fiber, and the thickness of the high absorber of the usage ratio of particulate water-absorbing agent can be thinner.

＜compact volume density 〉

(unit: g/ml) be the value of the quality of the whole agglomerated particle per unit volume of expression, this value has been filled a certain amount of agglomerated particle and has been made it solid container by the beating container by mensuration and obtained " compact volume density ".By patting, particle is more closely filled, usually, compact volume density is bigger than bulking volume density.So " degree of compression " one is as described below, the close difference of compact volume density and bulking volume has considerable influence to the flowability of particle.

In the particulate water-absorbing agent of the present invention, compact volume density is preferably at 0.65～0.85g/ml, and more preferably 0.68～0.80g/ml is most preferably in the scope of 0.70～0.80g/ml.

＜the degree of compression 〉

" degree of compression " (unit: %) be the value that obtains by compact volume density and bulking volume density calculation according to following equation.

The degree of compression=(P-A)/P * 100

Wherein, P is compact volume density, and A is a bulking volume density

The particle that the degree of compression is big goes out the interruption-forming bridge at the hopper of device easily.Like this, the mobile variation of these particles.And because padding, volume density is swung easily, makes stable supplying become difficult thus.This causes that water absorbing agent performance when making with actual the use reduces.

The degree of compression of particulate water-absorbing agent of the present invention is preferably in 0～18% scope, more preferably in 0～15% the scope, also more preferably in 0～10% scope.

＜flow down speed 〉

" flowing down speed " is the value of expression powder fluidity.In particulate water-absorbing agent of the present invention, intergranular frictional resistance reduces.Therefore, under the situation that does not reduce water absorption character, can increase the speed of flowing down.Especially, though the use amount of surfactant is minimum, can obtain positive effect.

In the particulate water-absorbing agent of the present invention, the speed that flows down is preferably in the scope of 5～15g/s, more preferably in the scope of 7～15g/s, most preferably in the scope of 10～15g/s.When flowing down speed more than or equal to 5g/s, this powder is easy to handle.When flowing down speed less than 5g/s, because powder is difficult to flow, particulate water-absorbing agent is difficult to handle, and this is not preferred.

＜stirring resistance 〉

The stirring resistance of particulate water-absorbing agent is to use rotary-type viscosimeter, estimates by the rotor rotation that makes viscosimeter in the container of having filled particulate water-absorbing agent.Because the frictional resistance between the particle of particulate water-absorbing agent of the present invention and device reduces, thereby can reduce the device load when carrying out surface-crosslinked handle and the damage of particulate water-absorbing agent, can reduce carry out air when carrying the device load and the damage of particulate water-absorbing agent, thereby make the stay in grade of particulate water-absorbing agent.Especially, though the use amount of surfactant is minimum, can obtain very big effect.

When the particulate water-absorbing agent that obtains among the present invention is measured with the assay method that illustrates among the following embodiment, preferably have the 0.37Ncm of being less than or equal to, more preferably have the 0.30Ncm of being less than or equal to, most preferably have the stirring resistance that is less than or equal to 0.25Ncm.

＜physiological saline flow conductivity (SFC) 〉

The physiological saline flow conductivity is the expand value of the liquid permeability when moistening of expression particulate water-absorbing agent, and its value is big more, and the liquid permeability is high more.

When resulting granules shape water absorbing agent of the present invention is measured with the assay method that illustrates among the following embodiment, preferably have more than or equal to 20 (10 ^-7Cm ³Sg ^-1), more preferably have more than or equal to 30 (10 ^-7Cm ³Sg ^-1), further preferably have more than or equal to 50 (10 ^-7Cm ³Sg ^-1), also more preferably greater than or equal 80 (10 ^-7Cm ³Sg ^-1) physiological saline flow conductivity (SFC/SalineFlow Conductivity).

(IV) absorber and/or absorbent commodity

It is the purposes of purpose that particulate water-absorbing agent of the present invention can be used for the suction, is widely used as absorber and absorbent commodity, is particularly suited for using as the hygienic material that absorbs body fluid such as urine and blood.In the present invention, absorber and absorbent commodity contain particulate water-absorbing agent of the present invention.

Here, so-called above-mentioned absorber is to be main component and the absorbing material of moulding with water-absorbing resins and hydrophilic fibre.Described absorber uses the particulate water-absorbing agent resin and the hydrophilic fibre of the invention described above to be shaped to for example film shape, tubular, sheet.Gross weight with water absorbing agent and hydrophilic fibre is a norm force machine, and above-mentioned absorber contains preferred 20～100 weight %, more preferably 30～100 weight %, the also more preferably particulate water-absorbing agent of 40～100 weight % (absorber concentration).In the above-mentioned absorber, the absorber concentration of particulate water-absorbing agent is high more, and the effect that the absorption characteristic of the particulate water-absorbing agent when making absorber and paper nappy etc. reduces is obvious more.In addition, above-mentioned absorber preferred thickness is the slim absorber of 0.1～5mm.

And this absorber comprises: (i) particulate water-absorbing agent, and it contains at the water-absorbing resins and the solid lubrication prescription that have crosslinked configuration by the resulting intramolecule of polymerization unsaturated monomer; (ii) hydrophilic fibre.

Especially, if use the particulate water-absorbing agent that has added the polymeric additive of being put down in writing among the present invention, the forming mixture of hydrophilic fibre and particle particulate water-absorbing agent is heated to the fusing point, glass branchpoint of this polymeric additive that adds to particulate water-absorbing agent or more than the softening point, can obtain to have more high-intensity absorber, wherein hydrophilic fibre and particulate water-absorbing agent are fixed, and particulate water-absorbing agent comes off hardly.

In addition, so-called above-mentioned absorbent commodity is the absorbent commodity that comprises above-mentioned absorber, has the surface sheet of liquid permeability and have the back foil of liquid impermeability.Above-mentioned absorbent commodity, especially the adult makes in the following manner with disposable diaper and feminine hygiene towel: at first, and with particulate water-absorbing agent and fiber base material (for example hydrophilic fibre) blend or make interlayer, thus formation absorber (absorbent cores).Then, absorber is clipped between base material (surface sheet) with liquid permeability and base material (back foil) with liquid impermeability.After this, as required, elastic elements, diffusion layer and/or adhesive tape.Under these conditions, the absorber compression forming is density and the 0.01～0.20g/cm of 0.06～0.50g/cc ²Mass area ratio.Employed fiber base material for example can be a hydrophilic fibre, the wood pulp of Fen Suiing for example, cotton fiber, cross-linked cellulose fibres, staple fibre, cotton, wool, cellulose acetate, vinylon etc.These fiber base materials are air lay preferably.

Absorbent article of the present invention has the excellent absorption characteristic.Such absorbent commodity comprises hygienic material particularly: the adult of a large amount of exploitations uses paper nappy recently; Children use diaper; Women's sanitary towel; Incontinence pad etc., but be not defined in this especially.When using absorbent article of the present invention, can reduce the liquid, aqueous amount of the absorption of returning in the particulate water absorbing agent that from absorbent article, contains, after absorbing water, kept excellent drying condition like this.As a result, can reduce the user that wears this absorbent article and ward's burden.

Below, according to embodiment and comparative example, the present invention will be described in more detail, and the present invention is not limited to these embodiment etc. in being no more than the scope of its aim.And, do not having under the situation about specifying, " part " is the meaning of weight portion.

And, measured each performance of particulate water-absorbing agent in order to descend method.And employed in an embodiment electrical equipment all uses under the condition of 100V, 60Hz.Further, use is adjusted to the particulate water-absorbing agent that is less than or equal to 6 weight % with moisture content.Unless special provision is arranged, carries out otherwise be determined under 25 ℃ ± 2 ℃, the condition of relative humidity 50%RH.And physiological saline uses the sodium-chloride water solution of 0.90 weight %.

(1) absorptivity (nothing for the sodium-chloride water solution of 0.90 weight % adds 5 minutes absorptivities (CRC2) and 30 minutes absorptivities (CRC1) of depressing)

0.2g particulate water-absorbing agent resin or water absorbing agent are put into the fabric bag of nonwoven (60mm * 60mm) equably.Then, this bag be impregnated in temperature adjustment to 25 ℃, far away in the sodium-chloride water solution (physiological saline) of the 0.90 weight % of excessive (for example being not less than 100g).After 5 minutes or 30 minutes bag is mentioned.After using centrifugal separator to carry out dehydration in 3 minutes, measure the weight W 2 (g) of bag with 250G.

And, under the situation of not using water absorbing agent and water-absorbing resins, carry out same operation, measure its weight W 1 (g).Then, calculate absorptivity (g/g) with this weight W 1, W2 by following (formula 1).

The weight (g) (formula 1) of absorptivity (g/g)=(weight W 2 (g)-weight W 1 (g))/water-absorbing resins

Use the aforementioned calculation formula to try to achieve the arrival rate (%) of the absorptivity (g/g) of 5 minutes and 30 minutes by 5 minutes absorptivities of following (formula 2) calculating.

The arrival rate of 5 minutes absorptivities (%)=5 minute absorptivity (g/g)/30 minute absorptivity (g/g) * 100 ... (formula 2)

And, above-mentioned 30 minutes absorptivity is added the absorptivity CRC1 that depresses as nothing.And, 5 minutes absorptivities are added the absorptivity CRC2 that depresses as nothing.

(2) add the absorptivity of depressing (sodium-chloride water solution of 0.90 weight % absorbs 60 minutes (AAP1) under the pressure of 2.03kPa)

Use device shown in Figure 1, mensuration adds the absorptivity of depressing (AAP).The loading 208 that pressure is adjusted to 2.03kPa (0.3psi) is provided.Attach the woven wire 202 of stainless steel 400 orders (mesh size is 38 μ m) to the bottom of the plastic cylinder 204 of internal diameter 60mm.Then, on above-mentioned mesh, scatter water-absorbing resins and particulate water-absorbing agent 0.90g (Wp2) equably.Subsequently, on water-absorbing resins or water absorbing agent, load above-mentioned loading 208 (during 0.3psi), measure the weight W a (g) of this cover determinator.

The glass filter 210 (Sogo Corporation's chemistry nitre making manufacturing, pore diameter 100～120 μ m) of diameter 90mm is set in the inboard of the petri diss 209 of diameter 150mm.After this, the sodium-chloride water solution (20～25 ℃) of 0.90 weight % is added to position with the glass filter upper surface flush.

On it, place again 1 diameter 90mm filter paper (ADVANTAEC Toyo Co., Ltd., trade name: (JIS P 3801, No.2), thickness 0.26mm keeps particle diameter 5 μ m), make the surface all soak, remove superfluous liquid.

The above-mentioned determinator of one cover is installed on the above-mentioned moistening filter paper, under loading, absorbs liquid.After 1 hour (60 minutes), take this cover determinator away, and measure its weight W b (g).Then, operating weight Wa, Wb calculate by following (formula 3) and add the absorptivity AAP1 (g/g) that depresses.

Add absorptivity AAP1 (g/g)=(Wb (g)-Wa (g))/water-absorbing resins depressed and quality (0.9) g of particulate water-absorbing agent) ... (formula 3)

And,, under 2.03kPa, measure though under 2.03kPa and 1.9kPa condition, can obtain roughly the same value.

(3) add the absorptivity of depressing; (the sodium-chloride water solution 4.83kPa (AAP2) of 0.90 weight %)

Except that the loading that will put on the 2.03kPa of water-absorbing resins or water absorbing agent in above-mentioned (2) becomes 4.83kPa (0.7Psi), carry out calculating identical operations with above-mentioned AAP1, add the absorptivity AAP2 (g/g) that depresses by following (formula 4) calculating.

Add absorptivity AAP2 (g/g)=(Wb (g)-Wa (g))/water-absorbing resins depressed and quality (0.9) g of water absorbing agent) ... (formula 4)

(4) weight (quality) average grain diameter

Use JIS standard screen screening water-absorbing resins or water absorbing agents such as 850 μ m, 710 μ m, 600 μ m, 500 μ m, 425 μ m, 300 μ m, 212 μ m, 150 μ m, 106 μ m, 75 μ m, the residual percentage of each granularity is plotted on the logarithmic probability paper.Thus, use the particle diameter that is equivalent to R=50% to read weight average particle diameter (D50).

And, distributing about particle diameter, the logstandard deviation value σ ζ that uses following (formula 5) expression is as index.Here, the value of σ ζ is more near 0, and it is narrow more to mean that particle diameter distributes.

σ ζ=1/2Ln (X2/X1) ... (formula 5)

(in the formula, X1, X2 are respectively: X1 is R=84.1 weight %, the X2 particle diameter when being R=15.9 weight %.)

And, following the carrying out of screening operation.Under the condition of room temperature (20～25 ℃), relative humidity 50%RH, 10g absorbent resin powder or particulate water-absorbing agent are put into above-mentioned JIS standard screen (The IIDATESTING SIEVE: internal diameter 80mm), use low screw tap type vibrating screen device (Co., Ltd. meal field makes made ES-65 type vibrating screen device) to carry out 5 minutes to 10 minutes classification.

And weight average particle diameter (D50) is the particle diameter of standard screen, and its mesh size is corresponding to the 50 weight % (for example, referring to United States Patent (USP) 5051259) of whole particles.。

(5) slamp value and the hydroscopicity during moisture absorption

Measure and write down the weight (A (g)) of the aluminium cup of diameter 52mm.About 2g is dispersed in this aluminium cup equably the total weight (B (g)) of record aluminium cup and water-absorbing resins or particulate water-absorbing agent by the water-absorbing resins or the particulate water-absorbing agent of JIS20 mesh (mesh size 850 μ m).Then, be positioned in the constant temperature and humidity device (manufacturing of PLATINOUS LUCIFER PL-2G Tabai Espec society) under 25 ℃ of temperature, the relative humidity 90%RH 1 hour.After 1 hour, measure and to put into the water-absorbing resins aluminium cup, after the moisture absorption or the aluminium cup total weight (C (g)) of particulate water-absorbing agent.(The IIDA TESTING SIEVE: internal diameter 80mm), (Co., Ltd. meal field makes made ES-65 type vibrating screen device to use low screw tap type vibrating screen device with putting into the water-absorbing resins of aluminium cup or the JIS standard screen that particulate water-absorbing agent moves to JIS8.6 mesh (mesh size 200 μ m) reposefully; Revolution 230rpm, vibration frequency 130rpm), under the condition of room temperature (20～25 ℃), relative humidity 50%RH, carry out classification in 5 seconds.Then, measure the weight (D (g)) of the water-absorbing resins remain on the 2000 μ m meshes or particulate water-absorbing agent and by the water-absorbing resins of this mesh or the weight (E (g)) of particulate water-absorbing agent.In the present invention, the slamp value during moisture absorption defines with following (formula 6), and hydroscopicity defines with following (formula 7), calculates by following (formula 6), following (formula 7) respectively.

Slamp value during moisture absorption (weight %)=((E (g))/(C (g)-A (g))) * 100 ... (formula 6)

Hydroscopicity (%)={ C (g)-B (g) }/(B (g)-A (g)) * 100 ... (formula 7)

(6) amount of water-soluble component (polymer content that can extract)

Measure the 0.9 weight % sodium-chloride water solution of 184.3g, and drop in the plastic containers with cover of 250ml capacity, in its aqueous solution, add 1.00g water-absorbing resins or particulate water-absorbing agent again, special teflon (registration mark) agitator arm that use is of a size of long 40mm * diameter 8mm (for example, Sogo Corporation physics and chemistry is learned the agitator arm A of nitre manufacturing) and magnetic stirrer 16 hours, making the whirlpool degree of depth is about 2cm (for example 250～350rpm).Soluble component (being mainly uncrosslinked water-soluble polymer) in extraction water-absorbing resins or the particulate water-absorbing agent.(ADVANTAEC Toyo Co., Ltd., trade name: (JIS P 3801, No.2), thickness 0.26mm keeps particle diameter 5 μ m) filters this extract with 1 filter paper.Obtain filtrate, the filtrate of measuring 50g is as measuring solution.

Then, measure the physiological saline that 50.0g does not add water-absorbing resins or particulate water-absorbing agent, at first, the NaOH aqueous solution titration of using 0.1N is to pH10, then, the HCl aqueous solution titration of using 0.1N obtains sky titer ([bNaOH] ml, [bHCl] ml) to pH2.7.

Said determination solution is carried out titration operation same as described above, try to achieve titer ([NaOH] ml, [HCl] ml).

Then, according to the above-mentioned empty titer and the titer of determined solution, calculate the soluble component amount of water-absorbing resins or particulate water-absorbing agent.Promptly, for example, when use comprises the water-absorbing resins of the acrylic acid of known quantity and sodium salt thereof or particulate water-absorbing agent, utilize the mean molecule quantity of monomer whose and the titer that obtains by aforesaid operations, can be by the soluble component amount in following (formula 8) calculating water-absorbing resins or the particulate water-absorbing agent.

Soluble component amount (weight %)=0.1 * (mean molecule quantity) * 184.3 * 100 * ([HCl]-[bHCl])/1000/1.0/50.0 ... (formula 8)

And, when water-absorbing resins that the composition of use unknown quantity constitutes or particulate water-absorbing agent, by above-mentioned titration, try to achieve neutralization ratio according to following (formula 9), use this neutralization ratio to calculate the mean molecule quantity of monomer, calculate the soluble component amount of water-absorbing resins or particulate water-absorbing agent again by above-mentioned (formula 8).

Neutralization ratio (mol%)=(1-([NaOH]-[bNaOH])/([HCl]-[bHCl])) * 100 ... (formula 9)

And, for example, when the water-absorbing resins that can not measure with said method in the water-absorbing resins that uses the unsaturated monomer do not contain carboxyl etc. to obtain or particulate water-absorbing agent, performance or particulate water-absorbing agent, the gravimetry of re-issuing the 10th～55 row record of the claim 23 in the patent Re37021 communique according to the U.S. is measured the amount of water-soluble component.

(7) surface tension

100ml beaker after abundant cleaning adds 50ml and is adjusted to 20 ℃ physiological saline, at first, measures the surface tension of physiological saline with surface tensiometer (K11 automatic surface tensometer, KRUSS society makes).In this was measured, capillary value need be in the scope of 71～75mN/m.Then,, drop into the rotor and the 0.5g particulate water-absorbing agent of the long fluorine resin system of 25mm after the fully flushing, under the condition of 500rpm, stirred 4 minutes to containing the beaker that is adjusted to physiological saline 20 ℃, after measuring surface tension.After 4 minutes, stop to stir, precipitate moisture particulate water-absorbing agent.After this, carry out the surface tension of same time-and-motion study supernatant.And, among the present invention, adopt the pole plate method of using the platinum plate, abundant clean plate before carrying out each mensuration, and use the blowtorch heated wash.

(8) mensuration of moisture content and solids content

1.000g water-absorbing resins or particulate water-absorbing agent are added in the above-mentioned aluminium cup (diameter 52mm),,, calculate the solids content percentage and the moisture content of water-absorbing resins or particulate water-absorbing agent according to its dry reduction with 180 ℃ no wind furnace heating 3 hours.

Here, above-mentioned solids content is water-absorbing resins or the particulate water-absorbing agent when removing volatile ingredient (being mainly water) from water-absorbing resins or particulate water-absorbing agent, the just pure resin Composition of water-absorbing resins or particulate water-absorbing agent.To be called solids content (weight %) with respect to the ratio of, the quality of above-mentioned solid constituent (amount of solids content) and the quality of water-absorbing resins that contains volatile ingredient or particulate water-absorbing agent.

In addition, above-mentioned moisture content is in water-absorbing resins or particulate water-absorbing agent, and the main component of the volatile ingredient that contains in water-absorbing resins or the particulate water-absorbing agent is the ratio of water (weight %), is equivalent to deduct above-mentioned solids content (weight %) from 100%.

(9) flow down the time (Flowability)

Utilize the flow down time measurement method (450.2-02) of EDANA (Europe is with promptly abandoning and non-weaving cloth association) regulation to measure.

Add 100g particulate water-absorbing agent or water-absorbing resins in the hopper of above-mentioned EDANA regulation, the moment that the inlet of hopper bottom is opened was measured particulate water-absorbing agent or whole times of discharging of water-absorbing resins of being added as the 0th second.And, be determined under 25 ℃, the condition of relative humidity 50%RH and carry out.

The mensuration of the amount (PIW) of (10) insertion distance (PID), insertion merit

＜working sample 〉

Add 27～30g water-absorbing resins or particulate water-absorbing agent to glass rounding columnar samples QC (external diameter 35mm, internal diameter 33mm, height 78mm, for example No. 7 screwed pipes making of Malem society etc.), fully vibration.After this, tapping (3 times/second, amplitude 10mm) up and down on iron plate, the state that makes interior water-absorbing resins of above-mentioned cylindrical sample pipe or particulate water-absorbing agent be in tight filling.Then, regulate by the amount that increases or reduce required particulate water-absorbing agent or water-absorbing resins, make that the height of the particulate water-absorbing agent of closely filling in the above-mentioned cylindrical sample pipe or water-absorbing resins (below, this water-absorbing resins or particulate water-absorbing agent are called stratum granulosum) is 45mm ± 1.5mm.Under the situation of the amount of adjusting particulate water-absorbing agent or water-absorbing resins by this way, gains are vibrated once more.After this, on iron plate, beat (3 times/second, amplitude 10mm) up and down 1 minute, thus particulate water-absorbing agent or water-absorbing resins in the tight filling sample pipe.And beat and to make that the stratum granulosum upper surface is smooth and level.

And, when measuring PIW, PID, owing to adopt the mean value of 3 measured values, measure each time, all add a cover, vibrate again, on iron plate, carry out same as described above beaing up and down (3 times/second again at the cylindric sample cell that forms above-mentioned stratum granulosum, amplitude 10mm) 1 minute, obtains the measurement sample of the smooth and level of the upper surface of stratum granulosum.

＜determinator 〉

Measuring PIW, PID uses determinator 10 as shown in Figure 2 to carry out.This determinator 10 (the KES-G5 obstacle compression testing machine that TecCato Co., Ltd. makes, parent company is in the kyoto, Japan Shinan District) comprising: the control device 12 of compression set 11, control compression set 11, obtain the data computing machine 13 of compression set 11 and control device 12.Above-mentioned compression set 11, control device 12, computer 13 are connected by cable.

Above-mentioned compression set 11 comprises as shown in Figure 3: movable step 3, insertion probe (insertion parts) 4, movable force cell (power meter) 5, displacement distance detector 6.

Above-mentioned step 3 is the platforms that load the working sample 2 that is filled with particulate water-absorbing agent or water-absorbing resins (hereinafter referred to as stratum granulosum) 1, can advance and retreat with respect to inserting probe 4.And above-mentioned insertion probe 4 is the metal bars that insert the stratum granulosum 1 that particulate water absorbing agent in the working sample 2 or water-absorbing resins constitute.In the present embodiment, above-mentioned insertion probe 4 as shown in Figure 4, diameter is 12.7mm, length is 40mm, the end has the anodized aluminum of the ball face of 5mm radius.And above-mentioned insertion probe 4 according to the standardized surface roughness of JISB0601-1994 is: usually maximum height is 0～10 μ m, is preferably 0～1 μ m; 10 mean roughness are 0～10 μ m, be preferably 0～1 μ m; Center line average roughness is 0～5 μ m, be preferably 0～1 μ m.Above-mentioned insertion probe 4 is fixed on the force cell 5 (Fig. 3) with screw as shown in Figure 4, can be whole mobile with force cell 5.

And it is the various loads of the upper limit that above-mentioned force cell 5 applies with the 10kg loading by the stratum granulosums 1 in 4 pairs of working samples of insertion probe 2.Above-mentioned force cell 5 is connected to displacement distance detector 6 as shown in Figure 3, and being arranged to can be with respect to working sample 2 advance and retreat.The displacement that above-mentioned displacement distance detector 6 detects force cell 5 is the displacement distance.

And as shown in Figure 2, above-mentioned control device 12 comprises: the insertion speed adjuster is used to adjust the insertion speed that inserts probe 4; The loading adjuster is used to adjust by inserting the loading that the stratum granulosum of probe 4 to working sample 2 applies; The displacement distance regulator is used to adjust the displacement distance of force cell 5; The displacement range display is used to show the displacement distance of force cell 5; The loading display is used to show the loading that the stratum granulosum to working sample 2 applies; Integrator.

And as shown in Figure 2, the data that computer 13 extraction compression sets 11 and control device 12 obtain are as numerical data.In this computer 13, the displacement of the insertion probe 4 (being force cell 5) that storage contacts with the upper surface of the stratum granulosum of working sample 2 apart from, be applied to the loading of above-mentioned stratum granulosum 1.

＜condition determination and assay method 〉

Said determination device 10 is placed on the non-vibrating horizontal bed,, measures PID, PIW according to the following steps adjusting under 25 ℃ ± 1 ℃, the environment of relative humidity 50 ± 5% conditions.

That is, the formation determination sample 2 in a manner described, do not apply vibration, this working sample 2 are arranged on the step 3 of compression set 11 (Fig. 2) of determinator 10.Then, as shown in Figure 3, step 3 rise make the end of inserting probe 4 be fixed to working sample 2 in the upper surface position contacting of stratum granulosum 1.With this state is starting point (0mm).

Then, stratum granulosum 1 is inserted in the end that will insert probe 4 with the insertion speed of 1mm/ second.When this insertion probe 4 begins to insert, obtain data and begin mensuration with 0.1 second interval, measure the insertion distance of inserting probe 4 and the required loading of insertion of inserting probe 4.And the insertion distance of inserting probe 4 is in the scope of above-mentioned starting point (0mm)～20mm (in the error 3%).

And, as shown in Figure 5, with the insertion of said determination distance (mm) as transverse axis, the loading of measuring is made chart as the longitudinal axis, the area (shaded area of Fig. 5) that curve that will be made of resulting loading value and transverse axis surround carries out integration at the insertion distance range of 0～20mm, obtains inserting the amount (PIW) of the insertion merit of the insertion probe 4 in distance 0～20mm scope.In addition, upper limit loading reaches under the situation of 10kg when the insertion distance reaches 20mm, and the insertion distance in the time of will reaching upper limit loading 10kg is as pid value.Insert loading no show 10kg and maximum when inserting distance and reaching 20mm, with 20mm as pid value.

Repeat above operation 3 times and measure, with the mean value of the value that obtains for 3 times as measured value.When the PID of above mensuration and PIW value hour, can think that so the particulate water-absorbing agent of stratum granulosum 1 or the particle of water-absorbing resins have more excellent sliding capability, and can think easier processing.

And the insertion distance of inserting probe 4 reaches before the 20mm, and when loading reached 10kg, the flowability of powder was considered to low-down, therefore can not obtain PIW, only estimated with the insertion distance (PID) of inserting probe 4.

(11) physiological saline flow conductivity (SFC)

The value of the liquid permeability when 0.69 the physiological saline flow conductivity (SFC) of weight % is expression particulate water-absorbing solvent swell.The value of SFC is big more, and the liquid permeability is high more.With the enforcement that is as the criterion of the physiological saline flow conductivity (SFC) of U.S. publication US2004-0106745-A.

Use device as shown in Figure 6, add particulate water-absorbing agent (0.900g) equably to pond 308 and in artificial urine, depress and carry out 60 minutes swellings, the height of the gel layer of record gel 310 in adding of 0.3psi (2.07kPa).Then, depress, allow the sodium-chloride water solution 306 of 0.69 weight % under constant hydrostatic pressing, flow out, by the gel layer of swelling from storage tank 302 in adding of 0.3psi (2.07kPa).

Storage tank 302 to device shown in Figure 6 inserts glass tube 304.The lower end of glass tube 304 is set, makes the liquid level of sodium-chloride water solution 306 of 0.69 weight % be arranged in the above 5cm in bottom of the swell gel 310 in pond 308.The sodium-chloride water solution 306 of 0.69 weight % in the storage tank 302 is supplied with to pond 308 by the L shaped pipe 312 that has tap.308 the bottom in the pond, be provided with collect pass through the collection container 314 of liquid.Collection container 314 is arranged on the top of smooth balance (even balance) 316.The internal diameter in pond 308 is 6cm, and bottom face is provided with the stainless steel woven wire of No.400 (mesh size 38 μ m) 318.Has the hole 322 that liquid is passed through in the bottom of piston 320.In the bottom, do not enter hole 322 for making particulate water-absorbing agent or its swell gel, the good glass filter 324 of permeability is installed.Pond 308 is arranged on the platform in pond 308, and the surface of this platform that contacts with the pond is arranged on stainless steel woven wire 326 tops that do not hinder liquid to see through.

Above-mentioned artificial urine prepares by mixing 0.25g calcium chloride dihydrate, 0.20g potassium chloride, 0.50g five aqueous magnesium chlorides, 2.0g sodium sulphate, 0.85g ammonium dihydrogen phosphate (ADP), 0.15g diammonium hydrogen phosphate and 994.25g pure water.

And the SFC test is carried out under room temperature (20～25 ℃).Use a computer and balance,, writing down time-varying amount of liquid by gel layer reached 10 minutes at interval with 20 seconds.Solution flow rate Fs (t) by the gel after the swelling 310 (mainly between particle) measures by removing gain in weight (g) with the increase time (s), is unit with g/s.The time that will reach constant hydrostatic pressing and stable flow velocity is as ts, only use ts and obtain data between 10 minutes and calculate flow velocity, the flow velocity that use is calculated at " ts " with between 10 minutes calculates the value of Fs (t=0), that is, and and the initial flow-rate of the solution by gel layer.Calculate Fs (t=0) by the t=0 that extrapolates by the result who counts roughly the function acquisition of representing the relation between Fs (t) and the t.Then, calculate physiological saline flow conductivity (adding the liquid penetration speed of depressing) with following formula (10).And the unit that adds the liquid penetration speed of depressing is (10 ^-7* cm ³* s * g ^-1).

Here,

Fs (t=0): the flow velocity of representing with g/s

L ₀: the height of the gel layer of representing with cm

Density (the 1.003g/cm of p:NaCl solution ²)

A: the area (28.27cm of the gel layer upside in the pond 41 ²)

Δ P: the hydrostatic pressing (4920dyne/cm that puts on gel layer ²).

(12) bulking volume density (volume weight)

Measure loose to density according to JIS K3362.Concrete is, uses as shown in Figure 7 determinator to measure by the following method.

1) determinator is placed on the stabilised platform, reconciles three thumb screws and keep the determinator level, perpendicular to shelf dry funnel 101 is installed, its end opening slightly seals with baffle plate 102.

2) under funnel 101, place cleaning-drying in advance, the metering quality is accurate to the cup 103 of 0.1g, then 100.0g is added in the funnel 101 by the sample of performance classification light and slowly.

3) promptly baffle plate 102 is opened fully, made the sample in the funnel 101 fall into cup 103 naturally.Sample, blends sample with glass bar during attached to funnel 101 in advance with bulk.Remove with glass bar (the about 8mm of diameter, the about 150mm of length) from the part of cup 103 protuberances, the quality of measuring the cup 103 that has sample is accurate to 0.1g.

Then, obtain bulking volume density according to following formula.

A＝(W ₂-W ₁)/V

Here,

A: bulking volume density (g/ml)

W ₂: the quality (g) that contains the cup of sample

W ₁: the quality (g) of empty cup

V: the capacity (ml) of cup.

And bulking volume density is called as volume density or volume weight more, and their implication is identical.

(13) flow down speed

Measure when measuring bulking volume density.Specifically, in the operation of measuring above-mentioned bulking volume density 3) in, from the moment of opening baffle plate 102 fully rapidly, measure whole samples and from funnel 101, fall the time that finishes.This time is t (s), obtains the speed of flowing down according to following formula.

Ve＝100/t

Here,

Ve: flow down speed (g/s).

(14) compact volume density

Measure in order to following method.

1) to fully cleaning in advance and dry, metering quality is accurate to graduated cylinder 0.1g, capacity 250ml, the about 38mm of internal diameter, utilize scraper to add the particulate water-absorbing agent of about 100g, metering has the quality of the graduated cylinder of sample, utilizes the quality m (g) of its difference calculation sample.

2) graduated cylinder that will have a sample is placed on the smooth experimental bench, carries out 100 tappings from the height of about 3mm, and the volume that correctly reads sample is accurate to 1ml.

3) then, repeat 100 tappings, read the volume of sample again,, adopt little volume V (ml), finish test if the difference that reads for twice is less than or equal to 1ml.

The difference that reads for twice repeats 100 tappings during greater than 1ml again, and the difference of the volume of measuring after double tapping is not more than 1ml, otherwise continues tapping.

If the difference that reads for twice is less than or equal to 1ml, adopt little volume V (ml), finish test.Obtain compact volume density according to following formula.

P＝m/V

Here,

P: compact volume density (g/ml).

(15) degree of compression

According to following formula, calculate the degree of compression by the value of bulking volume density A (g/ml) and compact volume density P (g/ml).

C＝(P-A)/P×100

Here,

C: the degree of compression (%).

(16) stir resistance

To RV12 type viscosimeter (product of HAAKE) SV2PSt type rotor and MV container are installed, with scraper particulate water-absorbing agent (about 80g) is added in the MV container, the amount of this water absorbing agent should be enough to hide fully the measure of resistance part of rotor, and rotor is rotated with 16rpm.Read the torque T (Ncm) of rotation beginning in the time of 1 minute, as the stirring resistance of particulate water-absorbing agent.

Reference example 1

In the aqueous solution (monomer concentration 38 weight %) of the PAA with 75 moles of % neutralization ratio of 5500g, dissolving 5.9g diacrylate macrogol ester (the average additional molal quantity 8 of ethylene oxide,1,2-epoxyethane) is as reactant liquor.Then, under nitrogen environment, make this reactant liquor degassing 30 minutes.Then, add a cover the formation reactor, supply with above-mentioned reactant liquor to this reaction vessel to the stainless steel both arms of the 10L type mixer that 2 sigma type blades and chuck are housed.When reactant liquor is remained on 30 ℃, fill this reactor with nitrogen.Then, in stirring reaction liquid, add 2.46g sodium peroxydisulfate and 0.10g L-ascorbic acid, after about 1 minute, the beginning polymerization.Then, under 30 ℃～90 ℃, carry out polymerization.The beginning polymerization was taken out the aqueous gel shaped polymer after 60 minutes.The diameter of the aqueous gel shaped polymer that obtains is crushed to about 5mm.The aqueous gel shaped polymer that this is broken is dispersed on the woven wire of 50 orders (mesh size 300 μ m), uses heated-air drying 90 minutes down at 150 ℃.Then, use the vibration flour mill to pulverize, use the woven wire classification of 20 orders (mesh size 850 μ m) again,, obtain the water-absorbing resins (a) of broken intermediate forms by blend.In 100 parts of water-absorbing resins that obtain (a), mix by 0.03 part of DGEEG, 0.5 part of propane diols, 0.3 part 1 4-butanediol, 3 parts of surface crosslinking agents that water constitutes.Said mixture 200 ℃ of following heat treated 45 minutes, is obtained water-absorbing resins (A).The σ ζ of resulting (A) is 0.35, and D50 is 370 μ m, is 2 weight % less than the ratio of the particle of 150 μ m, and the amount of soluble component is 17 weight %.

5 minutes, 30 minutes absorptivity of water-absorbing resins (A), the arrival rate of absorptivity, adding under 2.03kPa, the 4.83kPa, depress absorptivity and capillary measurement result is as shown in table 1; Slamp value during moisture absorption, hydroscopicity, the measurement result that flows down time, PID, PIW are as shown in table 2.

Reference example 2

Be provided with cooling tube, stirring vane and making in releasable flask motor, capacity 500ml of stirring vane rotation, add 14g acrylic acid, 6g acrylic acid octadecane ester, as 2 of the 0.1g of initator, 2 '-azodiisobutyronitrile (AIBN) and as the 80g ethylene glycol of solvent, the dissolving back is as reactant liquor fully.Then, under nitrogen environment, this reactant liquor was outgased 15 minutes.Then, under stream of nitrogen gas, flood the releasable flask that contains above-mentioned reactant liquor, carry out 2 hours polymerisations under stirring to 65 ℃ hot baths.After 2 hours, temperature is elevated to 75 ℃, further reacted 1 hour.Afterwards, cool off reactant liquor, obtain containing the solution (B-1) of polymeric additive, it contains the 20 weight % acrylic acid-acrylic acid octadecane ester copolymer as polymeric additive.

Embodiment 1

What the water-absorbing resins (A) that obtains in 100 parts of reference examples 1 added 1.5 parts (counting 0.3 part by polymeric additive), 5 parts (counting 1 part by polymeric additive) respectively contains polymeric additive solution (B-1,20 weight % ethanolic solutions), and mix, under 60 ℃, carry out vacuum drying in 3 hours afterwards, obtain particulate water-absorbing agent (1), (2).

The substance characteristics of the particulate water-absorbing agent that obtains (1) and (2) is shown in table 1, table 2-1, table 2-2.

Reference example 3

Be provided with cooling tube, stirring vane and making in releasable flask motor, capacity 500ml of stirring vane rotation, add 10g acrylic acid, 10g acrylic acid dodecane ester, as the 0.1g, 2 of initator, 2 '-azodiisobutyronitrile (AIBN) and as the 80g ethylene glycol of solvent, the dissolving back is as reactant liquor fully.Then, under nitrogen environment, with this reactant liquor degassing 15 minutes.Then, under stream of nitrogen gas, contain the releasable flask of above-mentioned reactant liquor, carry out 2 hours polymerisations under stirring to 65 ℃ Hot water immersion.After 2 hours temperature is increased to 75 ℃, reacted again 1 hour.Afterwards, cool off reactant liquor, obtain containing the solution (B-2) of polymeric additive, it contains the 20 weight % acrylic acid-acrylic acid dodecane ester copolymer as polymeric additive.

Embodiment 2

The water-absorbing resins (A) that obtains in 100 parts of reference examples 1 adds the solution (B-2 that contains polymeric additive of 5 parts (counting 1 part by polymeric additive), 20 weight % ethanolic solutions), and mix, under 60 ℃, carry out vacuum drying in 3 hours afterwards, obtain particulate water-absorbing agent (3).The substance characteristics of the particulate water-absorbing agent that obtains (3) is shown in table 1, table 2-1, table 2-2.

Embodiment 3

The water-absorbing resins (A) that obtains in 100 parts of reference examples 1 mixes the solution (B-2 that 5 parts (counting 1 part by polymeric additive) contain polymeric additive, 20 weight % ethanolic solutions) and the mixed solution of 0.1 part of DGEEG, under 120 ℃, carry out vacuum drying in 3 hours afterwards, obtain particulate water-absorbing agent (4).The substance characteristics of the particulate water-absorbing agent that obtains (4) is shown in table 1, table 2-1, table 2-2.

Reference example 4

Except that employed monomer was used 14g acrylic acid 2-hydroxyl ethyl ester replacement acrylic acid, other was identical with reference example 2, contains the solution that contains polymeric additive (B-3) of the 20% hydroxy-ethyl acrylate-acrylic acid octadecane ester copolymer as polymeric additive.

Embodiment 4

The water-absorbing resins (A) that obtains in 100 parts of reference examples 1 adds the solution (B-3 that contains polymeric additive of 5 parts (counting 1 part by polymeric additive), 20 weight % ethanolic solutions), and mix, under 60 ℃, carry out vacuum drying in 3 hours afterwards, obtain particulate water-absorbing agent (5).The substance characteristics of the particulate water-absorbing agent that obtains (5) is shown in table 1, table 2-1, table 2-2.

Reference example 5

To releasable flask motor, capacity 500ml that is provided with cooling tube, stirring vane and stirring vane is rotated, add 16g acrylic acid, 4g acrylic acid octadecane ester, as 2 of the 0.1g of initator, 2 '-azodiisobutyronitrile (AIBN) and as the 80g ethyl acetate of solvent, the dissolving back is as reactant liquor fully.Then, under nitrogen environment, this reactant liquor was outgased 15 minutes.Then, under stream of nitrogen gas, contain the releasable flask of above-mentioned reactant liquor to 70 ℃ hot bath dipping.After dipping beginning 10 minutes, separate out the polymer that polymerization generates, so reaction solution begins feculence, stop after 20 minutes stirring and react.40 minutes all curing of afterreaction system.After dipping beginning 3 hours, cooled reaction solution, the solidfied material that reaction is obtained 60 ℃ of dryings 5 hours under vacuum.Dried solids is fine grain aggregation, pulverizes with desk-top pulverizer, sieves by 75 μ m, obtains polymeric additive fine grained (B-4).

Observe resulting granules by SEM (SEM), found that, the aggregation of diameter 5～50 μ m that particle is made up of the particle of diameter 1～5 μ m.

Embodiment 5

The water-absorbing resins (A) that obtains in 100 parts of reference examples 1 adds 1 part of polymeric additive fine grained (B-4), obtains particulate water-absorbing agent (6) after the mixing.The substance characteristics of the particulate water-absorbing agent that obtains (6) is shown in table 1, table 2-1, table 2-2.

Reference example 6

To releasable flask motor, capacity 500m1 that is provided with cooling tube, stirring vane and stirring vane is rotated, add 14g acrylic acid, 6g acrylic acid dodecane ester, as 2 of the 0.1g of initator, 2 '-azodiisobutyronitrile (AIBN) and as the 80g ethyl acetate of solvent, the dissolving back is as reactant liquor fully.Then, under nitrogen environment, this reactant liquor was outgased 15 minutes.Then, under stream of nitrogen gas, dipping contains the releasable flask of above-mentioned reactant liquor in 70 ℃ hot bath.After dipping beginning 10 minutes, separate out the polymer that polymerization generates, so reaction solution begins feculence, stop after 20 minutes stirring and react.40 minutes all curing of afterreaction system.After dipping beginning 3 hours, cooling, the solidfied material that reaction is obtained 60 ℃ of dryings 5 hours under vacuum.Dried solids is fine grain aggregation, pulverizes with desk-top pulverizer, by the screening of 75 μ m sieves, obtains polymeric additive fine grained (B-5).

Observe resulting granules by SEM (SEM), found that, the aggregation of diameter 5～50 μ m that particle is made up of the particle of diameter 1～5 μ m.

Embodiment 6

The water-absorbing resins (A) that obtains in 100 parts of reference examples 1 adds 1 part of polymeric additive microparticle (B-5), obtains particulate water-absorbing agent (7) after the mixing.The substance characteristics of the particulate water-absorbing agent that obtains (7) is shown in table 1, table 2-1, table 2-2.

Reference example 7

To releasable flask motor, capacity 500ml that is provided with cooling tube, stirring vane and stirring vane is rotated, add 14g acrylic acid, 6g 2-ethylhexyl acrylate, 0.15g di-2-ethylhexylphosphine oxide acrylic amine, as the 0.1g, 2 of initator, 2 '-azodiisobutyronitrile (AIBN) and as the 80g ethyl acetate of solvent, the dissolving back is as reactant liquor fully.Then, under nitrogen environment, this reactant liquor was outgased 15 minutes.Then, under stream of nitrogen gas, contain the releasable flask of above-mentioned reactant liquor to 70 ℃ hot bath dipping.After 10 minutes, separate out the polymer that polymerization generates, so reaction solution begins feculence from the dipping beginning.Stop after 20 minutes stirring and reacting.Whole reaction system is solidified after 40 minutes.After 3 hours, cool off reactant liquor from the dipping beginning.The solidfied material that reaction is obtained 60 ℃ of dryings 5 hours under vacuum.Dried solids is fine grain aggregation, pulverizes with desk-top pulverizer, by 75 μ m screening, obtains polymeric additive fine grained (B-6).

Observe resulting granules by SEM (SEM), found that, the aggregation of diameter 5～50 μ m that particle is made up of the particle of diameter 1～5 μ m.

Embodiment 7

The water-absorbing resins (A) that obtains in 100 parts of reference examples 1 adds 1 part of polymeric additive fine grained (B-6), obtains particulate water-absorbing agent (8) after the mixing.The substance characteristics of the particulate water-absorbing agent that obtains (8) is shown in table 1, table 2-1, table 2-2.

Reference example 8

To releasable flask motor, capacity 500ml that is provided with cooling tube, stirring vane and stirring vane is rotated, add 10g acrylic acid, 5g acrylic acid octadecane ester, 5g methacrylic acid undecenyl hydroxyl macrogol ester (NKECONOMER, ML-12G: Xin Zhong village chemical industry Co., Ltd. makes), as 2 of the 0.1g of initator, 2 '-azodiisobutyronitrile (AIBN) and as the 80g ethyl acetate of solvent, the dissolving back is as reactant liquor fully.Then, under nitrogen environment, this reactant liquor was outgased 15 minutes.Then, under stream of nitrogen gas, flood the releasable flask that contains above-mentioned reactant liquor, carry out 2 hours polymerisations under stirring to 65 ℃ hot baths.After 2 hours temperature is increased to 75 ℃, reacted again 1 hour.Afterwards, cool off reactant liquor, obtain containing the solution that contains polymeric additive (B-7) of 20 weight % acrylic acid-acrylic acid octadecyl-methacrylic acid undecenyl hydroxyl polyethylene glycol ester copolymer as polymeric additive.

Embodiment 8

What the water-absorbing resins (A) that obtains in 100 parts of reference examples 1 added 5 parts (counting 1 part by polymeric additive) contains polymeric additive solution (B-7,20 weight % ethanolic solutions), and mix, under 60 ℃, carry out vacuum drying in 3 hours afterwards, obtain particulate water-absorbing agent (9).The substance characteristics of the particulate water-absorbing agent that obtains (9) is shown in table 1, table 2-1, table 2-2.

Compare reference example 1

To releasable flask motor, capacity 500ml that is provided with cooling tube, stirring vane and stirring vane is rotated, add 10g acrylic acid, 10g butyl acrylate, as 2 of the 0.1g of initator, 2 '-azodiisobutyronitrile (AIBN) and as the 80g ethyl acetate of solvent, the dissolving back is as reactant liquor fully.Then, under nitrogen environment, this reactant liquor was outgased 15 minutes.Then, under stream of nitrogen gas, flood the releasable flask that contains above-mentioned reactant liquor, carry out 2 hours polymerisations under stirring to 65 ℃ hot baths.After 2 hours temperature is increased to 75 ℃, reacted again 1 hour.Afterwards, the cooling reactant liquor obtains containing the contrast polymeric additive solution (C-1) of 20 weight % acrylic acid-butyl acrylate copolymer, only has the contrast polymeric additive of carbon number less than 7 alkyl as the side chain in its molecule.

Comparative example 1

The water-absorbing resins (A) that obtains in 100 parts of reference examples 1 adds the contrast polymeric additive solution (C-1 of 5 parts (counting 1 part by the contrast polymeric additive), 20 weight % ethanolic solutions), and mix, under 60 ℃, carry out vacuum drying in 3 hours afterwards, obtain comparative particle's shape water absorbing agent (CC-1).The substance characteristics of the comparative particle's shape water absorbing agent (CC-1) that obtains is shown in table 1, table 2-1, table 2-2.

Compare reference example 2

To releasable flask motor, capacity 500ml that is provided with cooling tube, stirring vane and stirring vane is rotated, add 10g salt acid acrylic acid dimethylamino ethyl ester, 10g butyl acrylate, as 2 of the 0.1g of initator, 2 '-azodiisobutyronitrile (AIBN) and as the 80g isopropyl alcohol of solvent, the dissolving back is as reactant liquor fully.Then, under nitrogen environment, this reactant liquor was outgased 15 minutes.Then, under stream of nitrogen gas, flood the releasable flask that contains above-mentioned reactant liquor, carry out 2 hours polymerisations under stirring to 65 ℃ hot baths.After 2 hours temperature is increased to 75 ℃, reacted again 1 hour.Afterwards, the cooling reactant liquor obtains containing the contrast polymeric additive solution (C-2) of 20 weight % acrylic acid-acrylic acid dimethylamino ethyl ester ester copolymer, only has the contrast polymeric additive of carbon number less than 7 alkyl as the side chain in its molecule.

Comparative example 2

The water-absorbing resins (A) that obtains in 100 parts of reference examples 1 adds the contrast polymeric additive solution (C-2 of 5 parts (counting 1 part by the contrast polymeric additive), 20 weight % aqueous isopropanols), and mix, under 60 ℃, carry out vacuum drying in 3 hours afterwards, obtain comparative particle's shape water absorbing agent (CC-2).The substance characteristics of the comparative particle's shape water absorbing agent (CC-2) that obtains is shown in table 1, table 2-1, table 2-2.Flow down the time owing to can not flow down and can not measure from hopper.This coccoid is mobile poor, has adherence, can be observed a large amount of powders attached to container.

Comparative example 3

The contrast absorbent (CC-2) that obtains in 100 parts of comparative examples 2 adds 0.5 part of hydrophily fine silica body as additive again, and (Aerogil 200, the average grain diameter 12nm:NipponAerogil of primary granule, Ltd. make), and mix, obtain comparative particle's shape water absorbing agent (CC-3).The substance characteristics of the comparative particle's shape water absorbing agent (CC-3) that obtains is shown in table 1, table 2-1, table 2-2.

Comparative example 4

The water-absorbing resins (A) that obtains in 100 parts of reference examples 1 adds 1 part of cross-linking type acrylic acid polymer fine powder body as additive (trade name: JUNLON PW-150: Nihon Junyaku Co., Ltd. makes: observing particle diameter with SEM is 5～50 μ m:1 weight % solution viscosity 95000cp), and mix, obtain comparative particle's shape water absorbing agent (CC-4).The substance characteristics of the comparative particle's shape water absorbing agent (CC-4) that obtains is shown in table 1, table 2-1, table 2-2.

Comparative example 5

The water-absorbing resins (A) that obtains in 100 parts of reference examples 1 adds 1 part of (average particulate diameter 12nm Nippon Aerogil of Aerogil 200 primary particles of the hydrophily fine silica body as additive, Ltd. make), and mix, obtain comparative particle's shape water absorbing agent (CC-5).The substance characteristics of the comparison particulate water-absorbing agent (CC-5) that obtains is shown in table 1, table 2-1, table 2-2.

5 minutes, 30 minutes absorptivities of the comparative particle's shape water absorbing agent (CC-1)～(CC-5) that obtains in the particulate water-absorbing agent that obtains among the embodiment 1～8 (1)～(9) and the comparative example 1～5, the arrival rate of 5 minutes absorptivities, 2.03kPa, adding under the 4.83kPa depress absorptivity, capillary measurement result is as shown in table 1; Slamp value during moisture absorption, hydroscopicity, flow down time, PID, PIW, bulking volume density, compact volume density, the degree of compression measurement result shown in table 2-1, table 2-2.

Table 1

		GV			AAP1 2.03kPa (g/g)	AAP2 4.83kPa (g/g)	Surface tension (mN/m)
								5 minutes (g/g)	30 minutes (g/g)	Arrival rate (%)
		Reference example 1	(A)	25							34	74	31	23	73
Embodiment 1 embodiment 1 embodiment 2 embodiment 3 embodiment 4 embodiment 5 embodiment 6 embodiment 7 embodiment 8	(1) (2) (3) (4) (5) (6) (7) (8) (9)				24 24 24 21 24 24 24 24 24	34 34 34 32 34 34 34 34 34	71 68 71 66 71 71 71 71 71	31 30 31 28 31 31 29 29 29	23 22 21 21 22 22 21 21 22	73 74 64 66 75 72 66 55 69
		Comparative example 1 comparative example 2 comparative examples 3 comparative examples 4 comparative examples 5	(CC-1) (CC-2) (CC-3) (CC-4) (CC-5)	24 24 24 24 24							34 34 34 34 34	71 71 71 71 71	25 30 26 24 26	12 21 16 11 13	44 33 35 73 73

Table 2-1

		Flow down the time (sec)	PID(mm)	PIW(g wt×mm)	Hydroscopicity (wt%)	Flow index during moisture absorption (wt%)
							Reference example 1	(A)	10	8	-	12	1
Embodiment 1 embodiment 1 embodiment 2 embodiment 3 embodiment 4 embodiment 5 embodiment 6 embodiment 7 embodiment 8	(1) (2) (3) (4) (5) (6) (7) (8) (9)	11 11 11 11 12 12 12 12 11	20 20 20 20 20 20 20 20 20	14300 9100 39200 34700 19500 12200 45300 47500 11400	10 8 10 10 9 10 10 10 9	99 100 95 100 100 100 96 95 100
							Comparative example 1 comparative example 2 comparative examples 3 comparative examples 4 comparative examples 5	(CC-1) (CC-2) (CC-3) (CC-4) (CC-5)	12 do not have mobile 15 11 12	9 20 10 7 7	- 9800 - - -	11 10 10 12 12	2 60 100 2 100

Table 2-2

		Loose bulk density (g/ml)	Compact type reactor density (g/ml)	The degree of compression (%)	D50(μm)	σζ	850/150 (％)
								Reference example 1	(A)	0.65	0.82	21	370	0.35	98.0
Embodiment 1 embodiment 1 embodiment 2 embodiment 3	(1) (2) (3) (4)	0.69 0.70 0.68 0.68	0.81 0.80 0.77 0.78	15 13 12 13	370 380 380 385	0.36 0.37 0.37 0.38	98.0 98.5 98.5 98.5

Embodiment 4 embodiment 5 embodiment 6 embodiment 7 embodiment 8	(5) (6) (7) (8) (9)	0.70 0.72 0.71 0.71 0.72	0.81 0.82 0.82 0.81 0.81	14 12 13 12 11	375 360 375 375 375	0.37 0.34 0.35 0.35 0.37	98.5 97.0 97.0 97.0 98.5
								Comparative example 1 comparative example 2 comparative examples 3 comparative examples 4 comparative examples 5	(CC-1) (CC-2) (CC-3) (CC-4) (CC-5)	0.66 0.65 0.63 0.68 0.62	0.82 0.82 0.79 0.84 0.77	19 21 20 19 19	375 400 370 370 370	0.35 0.40 0.35 0.35 0.35	97.0 99.0 98.0 97.0 98.0

Synthesis example 1: water-absorbing resins synthetic

Set the 48.5 weight % caustic soda aqueous solution for the 4.95g/ flow of second, set acrylic acid for the 6.12g/ flow of second, set 30 weight % polyethyleneglycol diacrylates (the number mean molecule quantity 523) aqueous solution (I) for the 0.0672g/ flow of second, the solution (II) that the diethylene-triamine pentaacetic acid trisodium of the 2-methylol-2-methyl propyl ketone of 0.989 weight portion and 1.08 weight portions is dissolved in 20 weight % acrylic acid aqueous solutions of 97.9 weight portions is set the 0.0758g/ flow of second for, set water for the 5.23g/ flow of second, supply with to agitator continuously, thereby mix these components.The temperature of monomer solution at this moment is 95 ℃.Flow with 0.223g/ second adds 3 weight % sodium persulfate aqueous solutions again, on insulation speed endless belt that move, effective length (the monomer supply port is to the distance of end of tape) 3.2m about 100 ℃, that divide with 1.7m/, supply with continuously with the material thickness of 4.9mm.Make with the rapid polymerization of go up supplying with of monomer solution, swelling when distributing steam begins to begin to shrink after about 1 minute from polymerization.Aqueous polymers after end of tape reclaims contraction imports meat grinder, continuously chopping.Aqueous polymers after the chopping, is pulverized with roller mill after dry 40 minutes with the air drier of temperature adjustment to 180 ℃.Then, crushed material is carried out classification with the JIS standard screen of mesh size 850 μ m and the JIS standard screen of mesh size 150 μ m, obtain the water-absorbing resins (raw polymer) that does not sieve by 850 μ m sieve by 150 μ m.

Embodiment 9

The coccoid of the water-absorbing resins that in the above-mentioned synthesis example 1 of 100 weight portions, obtains, mixing is by 1 of 0.34 weight portion, the surface crosslinking agent that the mixed liquor of polyoxyethylene (20) sorbitan monostearate of the propane diols of 4-butanediol, 0.56 weight portion, the water of 3.0 weight portions, 0.0010 weight portion (flower king (strain) makes) constitutes.Then, mixture 210 ℃ of following heat treated 30 minutes, is obtained surface-crosslinked particulate water-absorbing agent (10).The substance characteristics of particulate water-absorbing agent (10) is as shown in table 3.

Embodiment 10

Except the amount with polyoxyethylene (20) sorbitan monostearate changes 0.0015 weight portion into, carry out and the foregoing description 9 identical operations, obtain particulate water-absorbing agent (11).The substance characteristics of particulate water-absorbing agent is as shown in table 3.

Embodiment 11

Except the amount with polyoxyethylene (20) sorbitan monostearate changes 0.0020 weight portion into, carry out and the foregoing description 9 identical operations, obtain particulate water-absorbing agent (12).The substance characteristics of particulate water-absorbing agent is as shown in table 3.

Embodiment 12

Except the amount with polyoxyethylene (20) sorbitan monostearate changes 0.0050 weight portion into, carry out and the foregoing description 9 identical operations, obtain particulate water-absorbing agent (13).The substance characteristics of particulate water-absorbing agent is as shown in table 3.

Embodiment 13

Except the amount with polyoxyethylene (20) sorbitan monostearate changes 0.010 weight portion into, carry out and the foregoing description 9 identical operations, obtain particulate water-absorbing agent (14).The substance characteristics of particulate water-absorbing agent is as shown in table 3.

Comparative example 6

The coccoid of the water-absorbing resins that obtains in the above-mentioned synthesis example 1 of 100 weight portions mixes by 1 of 0.34 weight portion the surface crosslinking agent that the mixed liquor of the propane diols of 4-butanediol, 0.56 weight portion, the water of 3.0 weight portions constitutes.Then, mixture 210 ℃ of following heat treated 30 minutes, is obtained surface-crosslinked comparative particle's shape water absorbing agent (CC-6).The substance characteristics of comparative particle's shape water absorbing agent (CC-6) is as shown in table 3.

Embodiment 13

Except the amount with polyoxyethylene (20) sorbitan monostearate changes 0.015 weight portion into, carry out and the foregoing description 9 identical operations, obtain comparative particle's shape water absorbing agent (CC-7).The substance characteristics of comparative particle's shape water absorbing agent (CC-7) is as shown in table 3.

Table 3

	Embodiment					Comparative example
									9	10	11	12	13	6	7
Particulate water-absorbing agent	(10)	(11)	(12)	(13)	(14)	(CC-6)	(CC-7)
								The amount of surfactant (weight portion)	0.0010	0.0015	0.0020	0.0050	0.010	-	0.015
Surface tension (mN/m)	72.5	73.0	71.0	61.4	58.4	72.5	52.7
								CRC1(g/g)	30	30	31	31	31	30	31
AAP2(g/g)	26	25	25	25	24	25	24
								SFC (10 -7*cm 3* s*g -1)	43	45	42	42	39	45	39
Weight average particle diameter (μ m)	430	440	420	420	400	430	430
								Logstandard deviation	0.37	0.35	0.38	0.38	0.36	0.37	0.37
Bulking volume density (g/ml)	0.60	0.64	0.67	0.67	0.68	0.59	0.68
								Flow velocity (g/s)	8.7	9.0	8.7	8.8	8.9	7.6	9.0
Compact volume density (g/ml)	0.73	0.72	0.73	0.72	0.73	0.73	0.73
								The degree of compression (%)	17	11	8	6	7	20	6
Stir resistance (N*cm)	0.36	0.35	0.23	0.21	0.20	0.39	0.20
								PIW(g wt x mm)	37400	24200	7900	8500	7800	-	7400
PID(mm)	20	20	20	20	20	9	20
								850/150μm(％)	100	100	100	100	100	100	100

Synthesis example 2: water-absorbing resins synthetic

In the stainless steel both arms type mixer of the internal capacity 10L that 2 sigma type blades and chuck have been installed, to the aqueous solution of the PAA with 71.3 moles of % neutralization ratio, the polyethyleneglycol diacrylate of 0.10 mole of % of dissolving is as reactant liquor.Then, with nitrogen this reactant liquor was outgased 30 minutes.Then, add 10 weight % sodium persulfate aqueous solutions and 0.1 weight %L-aqueous ascorbic acid while stirring, begin polymerization after about 1 minute to reactant liquor.When pulverizing the gel that is produced, polymerization proceeds to the degree of 20-95%.In the time of 20 minutes, take out the gelatinous aqueous polymers that generates in polymerization.The aqueous gel shaped polymer that obtains is chopped into diameter approximately smaller or equal to 5mm.

With the aqueous polymers of this chopping 170 ℃ of following heated-air dryings 50 minutes.Dry polymer is pulverized with roller mill, carried out classification with the JIS standard screen of mesh size 850 μ m and the JIS standard screen of mesh size 150 μ m again, obtain not passing through the powder of the raw polymer of 150 μ m sieve by 850 μ m sieve.The powder of the raw polymer that obtains to 100 weight portions mixes by 1 of 0.5 weight portion, the surface crosslinking agent that the mixed liquor of the propane diols of 4-butanediol, 1.0 weight portions, the water of 3.0 weight portions constitutes.Then, mixture 210 ℃ of following heat treated 30 minutes, is obtained surface-crosslinked water-absorbing resins.

Embodiment 14

Plastic containers with the water-absorbing resins that obtains in the above-mentioned synthesis example 2 of 100g and 0.6mg zinc stearate are put into 500ml by vibration plastic containers mixing above-mentioned substance, obtain particulate water-absorbing agent (15).Measure the bulking volume density of the particulate water-absorbing agent (15) that obtains according to JIS K3362.But also the water absorption character (CRC2, AAP1, SFC) of mensuration particulate water-absorbing agent.The result is as shown in table 4.

Embodiment 15

Except that the amount of above-mentioned zinc stearate changes 0.15mg into, carry out and the foregoing description 14 identical operations, obtain particulate water-absorbing agent (16).And, with embodiment 14 in the same manner, measure the bulking volume density and the water absorption character (CRC2, AAP1, SFC) of the particulate water-absorbing agent (16) obtain.The result is as shown in table 4.

Comparative example 8

At the water-absorbing resins that obtains in the above-mentioned synthesis example 2 of 100g, not to wherein adding zinc stearate, carry out other with the foregoing description 14 identical operations, obtain comparison particulate water-absorbing agent (cc-8).And, with embodiment 14 in the same manner, measure relatively the bulking volume density and the water absorption character (CRC2, AAP1, SFC) of particulate water-absorbing agent (cc-8).The result is as shown in table 4.

Embodiment 16

The water-absorbing resins and the 1mg erucic acid ammonium that obtain in the above-mentioned synthesis example 2 of 100g are put into stainless steel beaker, in 150 ℃ countercurrent drier, placed 5 minutes.Take out beaker, insert thermometer mensuration temperature and be about 75 ℃.Vibrate slowly to mix behind the thermometric.Place cooling up to room temperature, obtain particulate water-absorbing agent (17).Measure the bulking volume density of the particulate water-absorbing agent (17) that obtains according to JIS K 3362.And, also measure the water absorption character (CRC2, AAP1, SFC) of particulate water-absorbing agent (17).The result is as shown in table 4.

Comparative example 9

Water-absorbing resins at obtaining in the above-mentioned synthesis example 2 of 100g does not add the erucic acid ammonium, carries out 16 identical operations with embodiment, obtains comparison particulate water-absorbing agent (cc-9).Then, with embodiment 16 in the same manner, measure relatively the bulking volume density and the water absorption character (CRC2, AAP1, SFC) of particulate water-absorbing agent (cc-9).The result is as shown in table 4.

And,, measure PID, PIW, surface tension about the particulate water-absorbing agent that obtains at the foregoing description 14～16 and comparative example 8,9 respectively.Its measurement result is as shown in table 4.

Table 4

	Embodiment			Comparative Examples
							14	15	16	8	9
Particulate water-absorbing agent	(15)	(16)	(17)	(cc-8)	(cc-9)
						The amount of water-absorbing resins (g)	100	100	100	100	100
Powdered lubricant type content (mg)	Zinc stearate 0.6	Zinc stearate 1.5	Erucic acid ammonium 1.0	/ /	/ /
						Loose volume density (bulk specific gravity) (g/ml)	0.70	0.72	0.70	0.67	0.66
Flow down speed (g/s)	/	/	11.4	/	10.2
						Absorbability (CRCI) (g/g)	30	30	31	30	31
Add the absorbability (AAP2) depressed (g/g)	25	26	25	25	25

Physiological saline flow conductivity (SFC) (10 -7*cm 3*s*g -1)	42	39	40	40	43
						PIW(g wt*mm)	22400	8100	1350	/	/
PID(mm)	20	20	20	7	7
						Surface tension (mN/m)	73	73	72	74	73
Compact volume density (g/ml)	0.82	0.83	0.83	0.83	0.82
						Compressible (%)	15	12	16	19	20
850/150μm(％)	100	100	100	100	100

Embodiment 17

The manufacturing of＜absorbent article 〉

Evaluation with absorbent article by following method manufacturing.

At first, the timber comminution pulp of particulate water-absorbing agent (1) that obtains in 50 weight portion the foregoing descriptions 1 and 50 weight portions carries out the dry type mixing with agitator.Then, use the wire screen that is formed with 400 meshes (openings of sizes 38 μ m),, make resulting mixture deposit, form the roll web of size 120mm * 400mm thus to be formed with the mode of air.Then, use 2kg/cm ²This roll web of pressure extrusion (196.14kPa) 60 seconds obtains weighing and is about 500g/m ²Water-absorbing body.Then, base lamina (liquid-tight thin slice), absorbent core that the polypropylene of opaque liquid constitutes and the saturating liquid top laminate that constitutes by the liquid permeability polypropylene, adopt double-sided belt to bond together mutually in proper order according to this, 2 so-called bracelets are installed on the object after this bonding, are obtained absorbent article (paper nappy).

The performance evaluation of＜absorbent article 〉

Make the top laminate of above-mentioned absorbent article be in top, be placed on the horizontal experimental bench, under the extended configuration that does not have wrinkle with fixing four jiaos of absorbent article of adhesive tape.Then, (140mm * 140mm), an acrylic panel is set then is provided with the cylinder of diameter 70mm, high 50mm in this acrylic panel centre, so that the position is poured liquid into from central division to place the metal gauze of 20 meshes (opening 850 μ m) thereon.And the quality of employed acrylic panel is 1.5kg.The foundary weight of 1 (totally 2) 4.25kg then, is set respectively on acrylic panel and in the both sides of cylinder.The quality of acrylic panel and the quality of foundary weight add up to 10kg, and the loading of water-absorbing body reaches 2.06kPa.Under this state, once drop into 0.9 weight % sodium-chloride water solution (physiological saline) 75ml from cylinder, measure the time of no liquid in cylinder.This timing definition is the liquid soak time.Place after 1 hour, repeat same operation, carry out the liquid input 4 times, measure the 1st～4 time liquid making time.After 1 hour, withdraw foundary weight, acrylic panel, metal gauze rapidly after the liquid input of the 4th.Continue to load 30 paper handkerchiefs of a cover clear and definite quality, size 140mm * 400mm, smooth acrylic panel, the foundary weight of 2 10kg.After 1 minute, measure except that foundary weight, the quality of paper handkerchief, and the mass change of mensuration paper handkerchief are returned wet amount with mensuration.

The 1st time short more to the liquid making time of the 4th, and absorbent article is good more.And it is few more to return wet amount, and water absorbing properties is good more.

Comparative example 10

For the comparison particulate water-absorbing agent (CC-1) that obtains in the above-mentioned comparative example 1, by with the foregoing description 17 identical operations, make absorbent article, assess performance.

Comparative example 11

For the comparison particulate water-absorbing agent (CC-5) that obtains in the above-mentioned comparative example 5, by with the foregoing description 17 identical operations, make absorbent article, assess performance.

The result that the absorbent article that obtains in the foregoing description 17 and the above-mentioned comparative example 10,11 is estimated is as shown in table 5 respectively.

Table 5

	Embodiment 17	Comparative Examples 10	Comparative Examples 11
				Absorbent	Particulate water-absorbing agent (1)	Comparative particle's shape water absorbing agent (cc-1)	Comparative particle's shape water absorbing agent (cc-5)
Liquid pours into the time (sec) for the first time	4	4	4
				Liquid pours into the time (sec) for the second time	17	16	16
Liquid pours into the time (sec) for the third time	22	27	22
				The 4th time liquid pours into the time (sec)	22	27	22

Return wet amount (g)

12

18

16

The above-mentioned specific embodiment and embodiment only are to be limitation of the invention for ins and outs of the present invention being described, should not be construed as, and in the claim scope of purport of the present invention and following record, can carry out various changes and implement.

Utilizability on the industry

Good fluidity during absorbent moisture absorption of the present invention owing to shown good absorption characteristic and volume density, can be used as various absorbing articles and uses. Go for particularly: use the hygienic materials (humor absorbent article) such as diaper, sanitary towel, so-called incontinence pad, wound protective material, trauma care material from the adult of in recent years phenomenal growth to children with paper nappy; Pet urine absorbing articles; Engineering material, for example, construction material, engineering water-keeping material, material water-proof material, packaging material etc.; Kitchen articles, for example, water droplet absorbent, Perserving materials, cold insulation material etc.; Various industrial article, for example, water-oil separating material, dewfall preventing agent, coagulating agent etc.; The agricultural or horticultural use article, for example, the water-keeping materials such as plant, soil etc. When using particulate water-absorbing agent of the present invention, because the amount of returning of urine etc. is little, significant dry feeling is arranged also after the suction, can greatly reduce the people of use absorbing articles and ward's burden.

Claims (21)

1. particulate water-absorbing agent, this particulate water-absorbing agent comprises the water-absorbing resins with cross-linked structure, this particle surface is undertaken crosslinked by adding surface conditioning agent, wherein: (i) mass median diameter (D50) is 200～600 μ m, and whole particulate water-absorbing agents with respect to 100 weight %, the particle size range that contains 95～100 weight % is to be equal to or greater than 150 μ m to the particulate water-absorbing agent less than 850 μ m, (ii) the logstandard deviation of size distribution (σ ζ) is 0.25～0.45, (iii) the degree of compression of calculating with following formula is in 0～18% scope, (iv) this particle-shape water-absorbing dispersant 0.5g is scattered in 20 ℃ of normal saline solutions of 50ml, the surface tension of crossing the supernatant after 4 minutes is for being equal to or higher than 55mN/m

The degree of compression (%)=(P-A)/P * 100

Wherein, P is the compact volume density of particulate water-absorbing agent, and A is the bulking volume density of particulate water-absorbing agent.

2. particulate water-absorbing agent as claimed in claim 1 is characterized by, with the insertion merit of insertion parts when the stratum granulosum of above-mentioned particulate water-absorbing agent is inserted into the 20mm degree of depth for 〉=0g weight * mm and≤75,0000g weight * mm.

3. particulate water-absorbing agent as claimed in claim 1 or 2 is characterized by, and contains surfactant or powdered lubricant in addition.

4. particulate water-absorbing agent as claimed in claim 3 is characterized by, and above-mentioned powdered lubricant is to have on the side chain 〉=alkyl of 7 carbon, mass median diameter be 〉=0.01 μ m and≤polymeric additive of 100 μ m.

5. particulate water-absorbing agent as claimed in claim 4 is characterized in that, with respect to the above-mentioned water-absorbing resins of 100 weight portions, the addition of above-mentioned polymeric additive be 〉=0.01 weight portion and≤10 weight portions.

6. as claim 4 or 5 described particulate water-absorbing agents, it is characterized in that, above-mentioned polymeric additive by general 〉=15wt% and≤have on the side chain of 100wt% 〉=monomer polymerization or the copolymerization of 7 carbon obtain, described wt% is a benchmark in polymer or the copolymer as polymeric additive.

7. as any described particulate water-absorbing agent of claim 4～6, it is characterized in that above-mentioned polymeric additive adds the state with solution or suspension on the surface of above-mentioned water-absorbing resins to.

8. as any described particulate water-absorbing agent of claim 4～7, it is characterized in that, above-mentioned polymeric additive as mass median diameter for 〉=0.01 μ m and≤powder of 100 μ m joins on the surface of above-mentioned water-absorbing resins.

9. particulate water-absorbing agent as claimed in claim 3 is characterized in that, with respect to the above-mentioned water-absorbing resins of 100 weight portions, the addition of above-mentioned surfactant is for being equal to or higher than 0.0005 weight portion and being equal to or less than 0.012 weight portion.

10. as claim 3 or 9 described particulate water-absorbing agents, it is characterized in that above-mentioned surfactant is the nonionic surfactant of HLB8～18.

11. a particulate water-absorbing agent is characterized in that, it contains water-absorbing resins and powdered lubricant (except the metallic soap), and with respect to above-mentioned water-absorbing resins, the content of above-mentioned lubricant is the scope of 0.0001 weight %～0.1 weight %.

12. any described particulate water-absorbing agent as claim 3～11 is characterized in that the absorptivity under the pressurized state under the 4.83kPa pressure (AAP2) is for being equal to or greater than 17g/g.

13. any described particulate water-absorbing agent as claim 4～8 is characterized in that the absorptivity under the pressurized state under the 2.03kPa pressure (AAP1) is for being equal to or greater than 20g/g.

14. any described particulate water-absorbing agent as claim 9～13 is characterized in that the physiological saline flow conductivity (SFC) of particulate water-absorbing agent is for being equal to or greater than 20 (10 ^-7Cm ³Sg ^-1).

15., it is characterized in that bulking volume density is 〉=0.7g/ml as any described particulate water-absorbing agent of claim 9～13.

16. any described particulate water-absorbing agent as in claim 4～8 and 11 is characterized in that, above-mentioned lubricant is added in the water-absorbing resins powder.

17. any described particulate water-absorbing agent as claim 1～16, it is characterized in that, above-mentioned water-absorbing resins has the shape at least a granulation thing that is selected from the granulation thing of amorphous crushed particles, amorphous crushed particles, the granulation thing of spheric granules, oval particle, perhaps has by the granulation thing of amorphous crushed particles, amorphous crushed particles, the granulation thing of spheric granules and the granulation thing of oval particle are mixed the shape that is obtained mutually.

18. contain the absorbent commodity of any described particulate water-absorbing agent of claim 1～17.

19. the manufacture method of a particulate water-absorbing agent, this method comprises: add to the water-absorbing resins with cross-linked structure and contain as (A) surface crosslinking agent of essential composition and (B) surface conditioning agent of surfactant or powdered lubricant, so that make the surface-crosslinked of water-absorbing resins, wherein, this water-absorbing resins with respect to 100 weight portions, the addition of this surfactant or powdered lubricant is 0.0005～0.012 weight portion, and, this particulate water-absorbing agent of 0.5g is scattered in 20 ℃ of normal saline solutions of 50ml, and the surface tension of crossing the supernatant after 4 minutes is for being equal to or greater than 55mN/m.

20. the manufacture method of particulate water-absorbing agent as claimed in claim 19, it is characterized in that, (i) mass median diameter (D50) of water-absorbing resins before surface-crosslinked is 200～600 μ m, and (ii) the logstandard deviation of size distribution (σ ζ) is 0.25～0.45.

21. the manufacture method as claim 19 or 20 described particulate water-absorbing agents is characterized in that, the degree of compression of calculating with following formula of above-mentioned particulate water-absorbing agent is in 0～18% scope;

The degree of compression (%)=(P-A)/P * 100

Wherein, P is the compact volume density of particulate water-absorbing agent, and A is the bulking volume density of particulate water-absorbing agent.

Images