WO2015030128A1 - Procédé de production d'une résine absorbant de l'eau - Google Patents

Procédé de production d'une résine absorbant de l'eau Download PDF

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Publication number
WO2015030128A1
WO2015030128A1 PCT/JP2014/072619 JP2014072619W WO2015030128A1 WO 2015030128 A1 WO2015030128 A1 WO 2015030128A1 JP 2014072619 W JP2014072619 W JP 2014072619W WO 2015030128 A1 WO2015030128 A1 WO 2015030128A1
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water
absorbent resin
raw material
producing
volume
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PCT/JP2014/072619
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English (en)
Japanese (ja)
Inventor
雄介 渡邉
寛隆 森部
幸作 安岡
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株式会社日本触媒
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Priority to JP2015534290A priority Critical patent/JP5989912B2/ja
Priority to KR1020167007078A priority patent/KR102329973B1/ko
Priority to CN201480043457.9A priority patent/CN105452303B/zh
Publication of WO2015030128A1 publication Critical patent/WO2015030128A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00—Processes of polymerisation
    • C08F2/01—Processes of polymerisation characterised by special features of the polymerisation apparatus used
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00—Processes of polymerisation
    • C08F2/002—Scale prevention in a polymerisation reactor or its auxiliary parts
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J3/00—Processes of treating or compounding macromolecular substances

Definitions

  • the present invention relates to a method for producing a water absorbent resin. More specifically, the present invention relates to a method for producing a water-absorbing resin that can stably and continuously supply a raw material for the water-absorbing resin.
  • Water-absorbent resin (SAP: Super Absorbent Polymer) is a water-swellable, water-insoluble polymer gelling agent, sanitary products such as paper diapers and sanitary napkins, water-retaining agents for agriculture and horticulture, and industrial waterstops. As absorbent articles such as materials, it is frequently used mainly for disposable applications. With regard to such a water absorbent resin, many monomers have been proposed as raw materials for the water absorbent resin or hydrophilic polymer.
  • water-absorbent resins With the improvement in performance of paper diapers, which are the main use of water-absorbent resins, many functions (physical properties) are required for water-absorbent resins.
  • specific examples of physical properties of the water-absorbing resin are not limited to high water absorption capacity, but include gel strength, water-soluble content, water absorption speed, water absorption capacity under pressure, liquid permeability, particle size distribution, urine resistance, Examples include antibacterial properties, impact resistance (damage resistance), powder flowability, deodorization, coloration resistance (whiteness), and low dust.
  • the manufacturing process of the water absorbent resin is divided into a number of processes.
  • the water-absorbent resin is continuously produced through steps such as polymerization, crushing of the gel-like water-absorbent resin, drying, pulverization, classification, surface crosslinking, and addition (Patent Documents 1 to 7).
  • the manufacturing process includes a process of supplying raw materials to the above processes.
  • the raw material of the water-absorbent resin includes, for example, a liquid containing a monomer in the polymerization process (Patent Document 8), a drying aid (Patent Document 9) in the gel crushing process after polymerization, and a surface cross-linking agent in the surface crosslinking process (Patent Document).
  • liquid permeability improvers in the addition step, liquid permeability improvers, deodorants, damage reducing agents and the like can be mentioned.
  • these documents do not describe the members to be specifically used. When the chemical resistance of the members used for the raw materials is low, elution of the members when supplying the raw materials for a long time. May cause problems.
  • Patent Document 31 describes a method for producing polymer particles by supplying a liquid containing a monomer into a reaction chamber containing a gas phase.
  • the cooling effect of the supply pipe line is adjusted by adjusting the ratio between the length of the pipe (supply pipe line) for supplying the liquid and the maximum diameter or by selecting a material used for the supply pipe line. To produce polymer particles of uniform quality.
  • Patent Document 32 describes a continuous production apparatus for a water absorbent resin. It has been studied to produce a water-absorbing resin having a uniform quality by a production apparatus using a material described in Patent Document 32.
  • Fluoro rubber is used as part of the material that supplies the water-absorbing resin material.
  • the present inventors have uniquely found the problem that the fluororubber gradually absorbs the raw material of the water-absorbent resin and the volume of the fluororubber is increased.
  • the present inventors have intensively studied. As a result, they have found a member whose volume is less likely to change compared to a conventionally used member even when it comes into contact with a water-absorbent resin raw material. Further studies have been made, and a method for continuously producing a water-absorbing resin having a uniform quality has been found, and the present invention has been completed. That is, the present invention includes the following inventions.
  • a member whose volume change rate after the immersion test is in the range of ⁇ 5 to + 5% is made of a movable part, a movable part, a raw material of the water absorbent resin, a raw material solution, or A method for producing a water-absorbent resin, which is used for at least a part of a part that contacts or a part that contacts the movable part and the movable part.
  • the movable part, the part in contact with the movable part, or the part in contact with the movable part and the movable part is used in at least one of a polymerization process, a gel crushing process, a surface crosslinking process, and an addition process.
  • the fluororesin is polytetrafluoroethylene, polyhexafluoropropylene, polyvinylidene fluoride, perfluoroalkoxy fluororesin, tetrafluoroethylene / hexafluoropropylene copolymer, ethylene / tetrafluoroethylene copolymer, [4]
  • a water-absorbing resin production apparatus used in the method for producing a water-absorbent resin according to any one of [1] to [8].
  • a member whose volume does not easily change as compared with a conventionally used member even when it contacts the raw material of the water-absorbent resin Or a part that contacts the movable part, the movable part, or a part that contacts the movable part and the movable part (hereinafter referred to as a movable part, a part that contacts the movable part, or a movable part and Since the portion in contact with the movable part is sometimes referred to as a “supply path”), the raw material can be continuously supplied with a stable capacity. Thereby, there exists an effect that the water absorbing resin which has uniform quality can be manufactured continuously.
  • FIG. 1 is the figure which looked at V # 7030 from the upper surface
  • (b) is V # 7030 by the arrow direction (lateral direction) of (a).
  • (C) is a diagram schematically showing a cross section of V # 7030.
  • a to B representing a numerical range means “A or more (including A and greater than A), B or less (including B and less than B)”, “%”. Means “% by mass”, and “part” means “part by mass”.
  • the manufacturing method of the water-absorbent resin according to the present invention includes a number of manufacturing steps such as a polymerization step, a gel pulverization step, a drying step, a pulverization step, a classification step, a surface crosslinking step, and an addition step.
  • the “manufacturing device” of the water-absorbent resin in the present invention is not only a main device such as a polymerization apparatus, a dryer, and a stirrer, but also a storage tank, a metering pump, a pipe, and It also includes various devices and associated equipment connected to the main unit of the polymerization apparatus, dryer, and stirrer, such as various devices such as a primary pressure regulating valve and a spray nozzle. That is, the “manufacturing apparatus” in the present invention refers to all apparatuses and facilities that come into contact with raw materials described later.
  • the “supply path” refers not only to piping from the storage tank to the main unit, for example, where raw materials are stored, but also to a metering pump, a primary pressure adjustment valve, and a spray nozzle provided in the middle of the piping.
  • Various devices such as various devices and associated facilities are also included.
  • the “movable part” in the present invention refers to (1) a part for adjusting raw materials and the like to stably produce a water-absorbing resin, and (2) a function (for example, stirring, stopper, etc.) by moving.
  • part it is not limited to the site
  • Specific examples of the above (1) include a primary pressure adjustment valve seat of a primary pressure adjustment valve, a valve body of a diaphragm pump, or an orifice portion of a flow rate controller.
  • Specific examples of the above (2) include a closer of a spray nozzle.
  • the “part in contact with the movable part” in the present invention may be in contact with the movable part, and the part in contact with the movable part itself is not movable.
  • Specific examples of the portion in contact with the movable part include a nozzle cushion of a spray nozzle, packing at the base of the blade shaft of a kneader type polymerization apparatus, and the like.
  • the method for producing a water-absorbent resin according to the present invention is a member whose volume is less likely to change even when it contacts the raw material and raw material solution of the water-absorbent resin (hereinafter referred to as “volume depending on the raw material”).
  • the raw material and the raw material solution may be supplied by using a member that is difficult to change ”in at least a part of the supply path of the manufacturing apparatus.
  • the “member whose volume is hardly changed by the raw material” refers to a member that hardly increases in volume even when it comes into contact with the raw material for producing the water-absorbent resin and is difficult to decrease in volume, that is, a water-absorbent resin.
  • the member whose volume is hardly changed by the raw material refers to a member whose volume change rate after the immersion test described later is within a specific range. Therefore, in the method for producing a water absorbent resin according to the present invention, a member whose volume change rate after the immersion test is within a specific range may be used in at least a part of the water supply resin raw material supply path. Specific test contents of the immersion test will be described later.
  • the volume change rate of the member in the present invention is preferably in the range of ⁇ 5 to + 5%, more preferably in the range of ⁇ 4 to + 4%, and in the range of ⁇ 3 to + 3%. More preferably, it is more preferably in the range of -2 to + 2%, and most preferably 0. That is, a member having a volume change rate within the above range is defined as “a member whose volume is hardly changed by a raw material” in the present invention.
  • immersing means immersing a member in actual use in a measurement raw material whose temperature is adjusted to 25 ° C. for one week (168 hours). More preferably, the above-mentioned member has a volume change rate in the above range even when immersed in a measurement raw material adjusted to a constant temperature (for example, 30 ° C.) within a range of 30 to 70 ° C. for at least one week. Further, it is desirable that the volume change rate be within the above range even when immersed for at least one month.
  • the measurement raw material for immersing the member when calculating the volume change rate is a raw material that the member may come into contact with in actual use, for example, a single raw material or a composition composed of a plurality of raw materials.
  • the member in the present invention does not have to be a member whose volume is difficult to change with respect to all the “raw materials” used in the production of the water-absorbent resin, and the volume changes with respect to the raw materials that may come into contact. Any difficult member may be used.
  • the member in the present invention does not swell and dissolve, the production apparatus using the member, that is, the dimension of the supply path of the raw material does not change, and the raw material can be continuously supplied with a stable capacity. Thereby, uniform quality water-absorbing resin can be manufactured continuously.
  • the raw material supply path is used in at least one of a polymerization step, a gel crushing step, a surface cross-linking step, and an addition step.
  • the polymerization step, the surface cross-linking step, and the addition step are steps for supplying raw materials that particularly affect the performance of the water-absorbent resin. Therefore, by supplying the raw material using the supply path using the above member, a stable capacity of the raw material can be continuously supplied, so that a water absorbent resin having a uniform quality is continuously manufactured. be able to.
  • the member in the present invention is particularly preferably used as a member of a part in contact with a raw material in a device such as a primary pressure regulating valve and a spray nozzle that is a part of a manufacturing apparatus and constitutes a part of a supply path.
  • a device such as a primary pressure regulating valve and a spray nozzle that is a part of a manufacturing apparatus and constitutes a part of a supply path.
  • the member in the present invention is preferably, for example, a pressure regulating valve seat provided in the primary pressure regulating valve, or a closer or nozzle cushion provided in the spray nozzle.
  • the member in the present invention may be used in other equipment, for example, a meter such as a flow meter.
  • a flow meter is provided downstream of the raw material supply path having the primary pressure regulating valve.
  • FIG. 1 is a schematic cross-sectional view showing an example of the overall configuration of the primary pressure regulating valve.
  • A indicates a flow path (supply path) through which the raw material passes
  • B indicates a pressure regulating valve seat.
  • Fig. 2 shows an example of a spray nozzle.
  • “C” indicates a closer and “D” indicates a nozzle cushion.
  • FIG. 3 shows an example of V # 7010 used for a gasket of a pipe flange made of a water-absorbent resin material or a gland packing of a control valve of each material.
  • FIG. 4 shows an example of V # 7030 used for a gasket of a piping flange, which is a raw material of a water absorbent resin.
  • the member in the present invention is not particularly limited as long as the volume change rate when immersed in the raw material of the water absorbent resin is ⁇ 5 to + 5%, but is preferably SUS or ceramic. That is, SUS and ceramic are preferable because the volume change rate when immersed in the measurement raw material is in the range of ⁇ 5 to + 5%.
  • the member in the present invention is preferably a fluororesin. That is, the fluororesin is preferable because the volume change rate when immersed in the measurement material of the water absorbent resin is in the range of ⁇ 5 to + 5%.
  • the fluororesin is preferable because the volume change rate when immersed in the measurement material of the water absorbent resin is in the range of ⁇ 5 to + 5%.
  • the fluororesin is not particularly limited, but polytetrafluoroethylene, polyhexafluoropropylene, polyvinylidene fluoride, perfluoroalkoxy fluororesin, tetrafluoroethylene / hexafluoropropylene copolymer, ethylene / tetrafluoroethylene copolymer And an ethylene / chlorotrifluoroethylene copolymer.
  • the above-mentioned fluororesin is preferable because it is excellent in wear and safety.
  • the “raw material” in the present invention refers not only to the monomer constituting the polymer but also to various compounds and chemicals used in the production of the water-absorbent resin. That is, the “raw material” in the present invention is a component of the water-absorbent resin (for example, a deodorant), changes to a component (for example, a monomer or a crosslinking agent), or changes to a component ( For example, polymerization initiator) refers to all compounds and drugs.
  • the “raw material” in the present invention may be in any form of liquid, gas or solid, preferably a compound having a boiling point of 25 ° C. or more at 1 atm, depending on the method of transporting the raw material of the water-absorbent resin, etc. May be diluted as appropriate.
  • a raw material used in a polymerization process or a surface cross-linking process is preferable, and it should be a liquid containing an organic compound having a carbonyl group, particularly a compound having a cyclic carbonyl structure. preferable.
  • the raw material is supplied from a storage tank to a main unit such as a polymerization apparatus, a drier, or a stirrer via a primary pressure adjustment valve and, if necessary, a spray nozzle.
  • a main unit such as a polymerization apparatus, a drier, or a stirrer via a primary pressure adjustment valve and, if necessary, a spray nozzle.
  • the “raw material solution” in the present invention refers to a solution in which the raw material is dissolved.
  • Examples of the “raw material solution” in the present invention are not particularly limited, but when the raw material in the present invention is in the form of gas or solid, the solution in which the raw material is dissolved, or the raw material in the present invention is liquid, In order to adjust viscosity etc., the solution etc. which the raw material melt
  • the “raw material solution” in the present invention includes not only a form directly used in the method for producing a water absorbent resin according to the present invention, but also a form before mixing with other raw material liquid and / or raw material.
  • the raw material solution is supplied from a storage tank to a main body device such as a polymerization apparatus, a dryer or a stirrer via a primary pressure regulating valve and, if necessary, a spray nozzle. Is done.
  • the “water-absorbent resin” in the present invention means a water-swellable, water-insoluble polymer gelling agent and has the following physical properties. That is, as an index of “water swellability” of a water-absorbing resin, a physical property having a CRC (water absorption capacity under no pressure) of 5 (g / g) or more as defined in ERT441.2-02 (2002), and a water-absorbing resin As an indicator of “water insolubility”, it means a polymer gelling agent having a physical property of Ext (water soluble content) defined by ERT470.2-02 (2002) of 50% by weight or less.
  • CRC water absorption capacity under no pressure
  • the water-absorbing resin can be designed as appropriate according to its use and is not particularly limited, but is preferably a hydrophilic cross-linked polymer obtained by cross-linking an unsaturated monomer having a carboxyl group. Further, the water-absorbing resin is not limited to a form in which the total amount (100% by weight) is a polymer, and the water-absorbing resin composition containing additives and the like within a range satisfying the physical properties (CRC, Ext). It may be.
  • water-absorbent resin in the present invention is not limited to the final product, but is an intermediate in the water-absorbent resin production process (for example, water-containing gel after polymerization, dried polymer after drying, water-absorbent resin powder before surface crosslinking, etc.) ), which are collectively referred to as “water absorbent resin”.
  • the shape of the water-absorbing resin includes a sheet shape, a fiber shape, a film shape, a particle shape, a gel shape, and the like.
  • a particulate water-absorbing resin is preferable.
  • the water-absorbing resin produced by the production method according to the present invention is not particularly limited, but desirably has the following physical properties.
  • the water absorption capacity of the water-absorbent resin in the present invention is preferably 10 to 100 [g / g] (CRC: Centrifuge Retention Capacity (also referred to as “centrifuge retention capacity”)), It is more preferably 15 to 60 [g / g], and further preferably 20 to 50 [g / g].
  • CRC Centrifuge Retention Capacity
  • “CRC” means that 0.200 g of a water-absorbent resin in a non-woven bag is freely swollen in a large excess of 0.9 wt% sodium chloride aqueous solution for 30 minutes, and a centrifuge is used.
  • the water-absorbing resin having a CRC of 10 [g / g] or more is preferable because of its high water absorption ratio.
  • the CRC standard deviation of the obtained water-absorbent resin can be within the range of 0.2 to 0.3. Therefore, it is possible to provide a water absorbent resin having a uniform water absorption ratio.
  • the liquid permeability of the water-absorbent resin in the present invention is 10 ⁇ 10 ⁇ 7 [cm 3 ⁇ g / sec] or more. Is preferably 15 ⁇ 10 ⁇ 7 [cm 3 ⁇ g / sec] or more, and more preferably 20 ⁇ 10 ⁇ 7 [cm 3 ⁇ g / sec] or more.
  • SFC refers to the liquid permeability of a 0.69 wt% sodium chloride aqueous solution with respect to 0.9 g of the water absorbent resin under a load of 2.07 kPa.
  • the water-absorbing resin having an SFC of 10 ⁇ 10 ⁇ 7 [cm 3 ⁇ g / sec] or more is preferable because of its high liquid permeability.
  • the SFC standard deviation of the obtained water-absorbent resin can be kept within a range of 2 to 3. Therefore, it is possible to provide a water absorbent resin having uniform liquid permeability.
  • the method for producing the water absorbent resin according to the present invention will be described in detail below.
  • the method for producing a water-absorbent resin according to the present invention is not limited to a production process comprising the steps described below, and appropriately includes steps for imparting desired properties of the water-absorbent resin.
  • This step is a step in which an aqueous gel-based crosslinked polymer (hereinafter sometimes referred to as "hydrated gel") is obtained by polymerizing an aqueous solution containing the following monomers as main components. .
  • hydrated gel an aqueous gel-based crosslinked polymer
  • the water-absorbing resin obtained by the production method according to the present invention preferably uses the following monomers as raw materials.
  • the monomer (monomer) concentration is preferably in the range of 10 to 70% by weight, more preferably in the range of 15 to 65% by weight, and particularly preferably in the range of 20 to 60% by weight.
  • Examples of the monomer include unsaturated carboxylic acids, anionic unsaturated monomers, unsaturated monomers having a sulfo group, unsaturated monomers having a phosphate group, unsaturated monomers having an amide group, and unsaturated monomers having an amino group.
  • Examples thereof include saturated monomers, unsaturated monomers having a phenolic hydroxyl group, and salts thereof.
  • unsaturated carboxylic acid examples include acrylic acid, methacrylic acid, maleic acid, itaconic acid, cinnamic acid, crotonic acid and the like.
  • anionic unsaturated monomer examples include maleic anhydride and fumaric anhydride.
  • Examples of the unsaturated monomer having a sulfo group include vinyl sulfonic acid, allyl toluene sulfonic acid, vinyl toluene sulfonic acid, styrene sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, and 2- (meth).
  • Examples include acryloylethane sulfonic acid and 2- (meth) acryloylpropane sulfonic acid.
  • Examples of the unsaturated monomer having a phosphate group include 2-hydroxyethyl (meth) acryloyl phosphate.
  • Examples of the unsaturated monomer having an amide group include (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide and the like.
  • Examples of the unsaturated monomer having an amino group include N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylamide and the like. Can be mentioned.
  • the neutralization rate of the monomer is preferably in the range of 40 to 90 mol%, and more preferably in the range of 50 to 80 mol%. .
  • the polymerization initiator used in the production method according to the present invention is appropriately selected depending on the polymerization form, and is not particularly limited.
  • a photodegradable polymerization initiator a thermal decomposition polymerization initiator, a redox polymerization start Agents and the like.
  • Examples of the photodegradable polymerization initiator include benzoin derivatives, benzyl derivatives, acetophenone derivatives, benzophenone derivatives, and azo compounds.
  • Examples of the thermal decomposition polymerization initiator include persulfates such as sodium persulfate, potassium persulfate, and ammonium persulfate; peroxides such as hydrogen peroxide, t-butyl peroxide, and methyl ethyl ketone peroxide; azonitrile Compound, azoamidine compound, cyclic azoamidine compound, azoamide compound, alkylazo compound, 2,2′-azobis (2-amidinopropane) dihydrochloride, 2,2′-azobis [2- (2-imidazolin-2-yl) propane] Azo compounds such as dihydrochloride; and the like.
  • Examples of the redox polymerization initiator include a system in which a reducing compound such as L-ascorbic acid or
  • polymerization initiators may be used alone or in combination of two or more. That is, for example, the combined use of the photodegradable polymerization initiator and the thermal decomposable polymerization initiator is also a preferred embodiment.
  • the amount of the polymerization initiator used is preferably in the range of 0.001 to 2% by weight, more preferably in the range of 0.01 to 0.5% by weight, based on the monomer.
  • the usage-amount of the said polymerization initiator exceeds 2 weight%, there exists a possibility that the water soluble component of a water absorbing resin may increase.
  • the usage-amount of the said polymerization initiator is less than 0.001 weight%, there exists a possibility that an unreacted monomer may increase and a residual monomer may increase in the water-absorbing resin obtained.
  • radical initiation accelerator a compound that promotes the generation of radicals
  • radical initiation accelerator a compound that promotes the generation of radicals
  • a radical initiation promoter For example, a reducing agent is mentioned.
  • the photodegradable polymerization initiator also functions as a radical initiation accelerator.
  • reducing agent examples include (heavy) sulfurous acid (salt) such as sodium sulfite and sodium hydrogen sulfite; reducing metal (salt) such as L-ascorbic acid (salt) and ferrous salt; amines and the like. It is done.
  • Internal crosslinking agent In the production method according to the present invention, it is preferable to use a cross-linking agent (hereinafter referred to as “internal cross-linking agent”) from the viewpoint of the water-absorbing performance of the resulting water-absorbent resin.
  • internal crosslinking agent a cross-linking agent which reacts with the double bond of a monomer
  • the reactive crosslinking agent which reacts with the carboxyl group of a monomer or a crosslinking agent which has these characteristics together Etc.
  • polymerizable crosslinking agent examples include N, N′-methylenebis (meth) acrylamide, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, and trimethylolpropane tri (meth).
  • the reactive crosslinking agent examples include polyglycidyl ether, (poly) ethylene glycol diglycidyl ether, glycerol diglycidyl ether, ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, glycerin, sorbitol, propanediol, Ions such as 1,4-butanediol, pentaerythritol, ethylenediamine, ethylene carbonate, propylene carbonate, polyethyleneimine, covalent crosslinkers such as polyhydric alcohols such as glycidyl (meth) acrylate, and polyvalent metal compounds such as aluminum salts Examples thereof include a binding cross-linking agent, and a compound having two or more reactive groups in one molecule.
  • the internal cross-linking agents may be used alone or in combination of two or more.
  • the internal cross-linking agent may be added to the aqueous solution containing the monomer as a main component before the start of polymerization, or may be added in a plurality of times. Moreover, you may add to the polymer after superposition
  • the amount of the internal crosslinking agent used is preferably in the range of 0.001 to 5 mol%, preferably in the range of 0.001 to 3 mol% with respect to the monomer excluding the internal crosslinking agent from the viewpoint of physical properties. Is more preferable, and the range of 0.001 to 2 mol% is particularly preferable.
  • the usage-amount of the said internal crosslinking agent exceeds 5 mol%, there exists a possibility that physical properties, such as a water absorption rate of a water absorbing resin, may fall.
  • the usage-amount of the said polymerization initiator is less than 0.001 mol%, there exists a possibility that the water solubility of a water absorbing resin may increase.
  • a chelating agent for the purpose of improving the color stability (color stability when stored for a long time under high temperature and high humidity) or urine resistance (preventing gel degradation) of the resulting water-absorbent resin Is preferably used.
  • the chelating agent is not particularly limited, and examples thereof include polyvalent carboxylic acids. Specific examples include diethylenetriaminepentaacetic acid, triethylenetetraaminehexaacetic acid, cyclohexane-1,2-diaminetetraacetic acid, N-hydroxyl.
  • Ethylethylenediaminetriacetic acid ethylene glycol diethyl etherdiaminetetraacetic acid, ethylenediaminetetrapropionic acetic acid, N-alkyl-N′-carboxymethylaspartic acid, N-argenyl-N′-carboxymethylaspartic acid, and alkali metal salts and alkalis thereof
  • An earth metal salt, an ammonium salt, or an amine salt is mentioned.
  • the salt may be completely neutralized or partially neutralized.
  • These chelating agents may be used individually by 1 type, or may use 2 or more types together.
  • the amount of the chelating agent used is preferably within the range of 0 to 20000 ppm, more preferably within the range of 0 to 15000 ppm, and particularly preferably within the range of 0 to 10,000 ppm with respect to the water-absorbent resin.
  • water-soluble resins or water-absorbent resins such as starch, cellulose, polyvinyl alcohol (PVA), polyacrylic acid (salt), polyethyleneimine;
  • Add optional components such as various foaming agents such as salts, azo compounds, and bubble generating agents; surfactants; additives, etc. to any of monomer aqueous solution, hydrous gel, dry polymer, water absorbent resin, etc. Can do. That is, the above arbitrary components can be added in any of the production steps in the present invention.
  • An ⁇ -hydroxycarboxylic acid compound and an inorganic reducing agent can be used.
  • the polymerization method is not particularly limited, and sprayed droplet polymerization or reverse phase suspension polymerization may be employed to obtain a particulate hydrous gel or aqueous solution polymerization. It may be employed to obtain a hydrogel.
  • the aqueous solution polymerization may be tank type (silo type) non-stir polymerization, but is preferably kneader polymerization or belt polymerization, more preferably continuous aqueous solution polymerization, further preferably high concentration continuous aqueous solution polymerization, particularly preferably high concentration / high temperature. Initiated continuous aqueous polymerization can be employed.
  • stirring polymerization means superposing
  • the main polymerization step is a step in which the above-described monomers, polymerization initiator, radical initiation accelerator, internal cross-linking agent, chelating agent and other raw materials are supplied through at least the primary pressure regulating valve.
  • the specific aqueous solution concentration of each raw material is preferably the following value: when the polymerization initiator is sodium persulfate, 1 to 30% by weight aqueous solution; when the radical initiation accelerator is sodium L-ascorbate 0.1 to 10% by weight aqueous solution; 1 to 30% by weight aqueous solution when the internal crosslinking agent is polyethylene glycol diacrylate; 1 to 50% by weight aqueous solution when the chelating agent is trisodium diethylenetritriaminepentaacetic acid.
  • the temperature at the time of supplying the monomer is preferably within a range of 20 to 100 ° C., more preferably within a range of 25 to 95 ° C., and particularly preferably within a range of 30 to 90 ° C.
  • the temperature at the time of supplying the polymerization initiator is preferably in the range of 0 to 50 ° C., more preferably in the range of 3 to 40 ° C., and particularly preferably in the range of 5 to 30 ° C.
  • the temperature at the time of supplying the radical initiator accelerator is preferably in the range of 0 to 50 ° C., more preferably in the range of 3 to 40 ° C., and particularly preferably in the range of 5 to 30 ° C.
  • the temperature at the time of supplying the internal cross-linking agent is preferably within the range of 5 to 90 ° C, more preferably within the range of 10 to 80 ° C, and particularly preferably within the range of 15 to 70 ° C.
  • the temperature at the time of supplying the chelating agent is preferably in the range of 3 to 50 ° C, more preferably in the range of 5 to 40 ° C, and particularly preferably in the range of 10 to 30 ° C.
  • the raw material such as the monomer is supplied without substantially changing the volume of the member used in the primary pressure regulating valve. be able to. Thereby, the raw material of the stable capacity
  • Gel pulverization step This step is a step of obtaining a particulate hydrogel crosslinked polymer by subdividing the hydrogel crosslinked polymer during or after polymerization. Note that this step is referred to as “gel pulverization” to distinguish from “pulverization” in the following (4) pulverization step and classification step. In this step, the water-containing gel-like crosslinked polymer is subdivided into a size that is about a fraction of the original size.
  • the gel pulverization apparatus used in the present gel pulverization step is not particularly limited as long as the polymer obtained by polymerization can be subdivided, and various apparatuses, methods, and the like can be suitably used.
  • the method for producing a water-absorbent resin in the present invention may include a drying assistant supply step, if necessary.
  • This step is a step of supplying a drying aid to the particulate hydrogel crosslinked polymer obtained in the gel pulverization step.
  • drying aid means that the hydrogel crosslinked polymers are prevented from fusing together in the step of drying the hydrogel crosslinked polymer in a stationary state, This refers to a compound that can improve the air permeability of hot air and improve the drying efficiency.
  • the drying aid may be either liquid or solid.
  • the shape is not particularly limited, but is preferably granular, and more preferably spherical, granular, crushed, needle-like, flake-like, and these primary particles are fused together. Agglomerated.
  • drying aid examples include monohydric alcohols having 10 to 16 carbon atoms, monohydric alcohols having 17 to 30 carbon atoms, polyhydric (2 to 5 valent) alcohols having 6 to 16 carbon atoms, and polyhydric alcohols having 6 to 30 carbon atoms.
  • examples thereof include monovalent (hexavalent) alcohol, silicone oil, modified silicone oil, oxyethylene-containing compound, oxypropylene-containing compound and ester.
  • Examples of the monohydric alcohol having 10 to 16 carbon atoms include n-decyl alcohol, n-dodecyl alcohol, n-tetradecyl alcohol, n-pentadecyl alcohol, n-hexadecyl alcohol, isodecyl alcohol, isododecyl alcohol, Examples include tetradecyl alcohol, isopentadecyl alcohol, and isohexadecyl alcohol.
  • Examples of the monohydric alcohol having 17 to 30 carbon atoms include n-octadecyl alcohol, n-icosyl alcohol, n-triacontyl alcohol, isooctadecyl alcohol, isoicosyl alcohol and isotriacontyl alcohol.
  • Examples of the polyhydric (2-5 pentahydric) alcohol having 6 to 16 carbon atoms include 1,6-hexanediol, 1,10-decanediol, 1,12-dodecanediol, 1,14-tetradecanediol, 1,16 -Hexadecanediol, diglycerin, triglycerin and the like.
  • polyhydric (hexavalent) alcohol having 6 to 30 carbon atoms examples include dipentaerythritol, tetraglycerin and sorbitol.
  • silicone oil examples include dimethyl silicone oil having a viscosity at 25 ° C. of 5 to 30000 mPa ⁇ s, preferably 10 to 10000 mPa ⁇ s, more preferably 15 to 5000 mPa ⁇ s, and particularly preferably 20 to 1000 mPa ⁇ s. .
  • modified silicone oil examples include alkyl-modified silicone oil (KF-412: manufactured by Shin-Etsu Chemical Co., Ltd., and SH230: manufactured by Toray Dow Corning Co., Ltd.), and phenyl-modified silicone oil (SH510: manufactured by Toray Dow Corning Co., Ltd.).
  • Fluorine-modified silicone oil (FS1265: manufactured by Toray Dow Corning Co., Ltd.), amino-modified silicone oil (KF-880: manufactured by Shin-Etsu Chemical Co., Ltd., and SF8417: manufactured by Toray Dow Corning Co., Ltd.), epoxy Modified silicone oil (KF105: manufactured by Shin-Etsu Chemical Co., Ltd., and SF8411: manufactured by Toray Dow Corning Co., Ltd.), phenol-modified silicone oil (X-22-1821: manufactured by Shin-Etsu Chemical Co., Ltd., and BY16-752: Toray Industries, Inc. ⁇ Dowconi Etc.), carboxyl-modified silicone oil (X-22-3701E: manufactured by Shin-Etsu Chemical Co., Ltd., and SF8418: manufactured by Toray Dow Corning Co., Ltd.), mercapto-modified silicone oil (KF-2001: Shin-Etsu Chemical Co., Ltd.) And methacryl-modified silicone oil (K
  • the viscosity (mPa ⁇ s) of the modified silicone oil is preferably 5 to 30000, more preferably 10 to 10,000, and particularly preferably 20 to 3000 from the viewpoint of drying efficiency and handling properties.
  • the modification position (both terminal modification, one terminal modification, side chain modification, etc.) and the degree of modification of the modified silicone oil are not particularly limited.
  • oxyethylene-containing compound there can be used an ethylene oxide 1 to 8 mol adduct of alcohol and an ethylene oxide 1 to 8 mol adduct of carboxylic acid.
  • the number of added ethylene oxide (mole) is preferably 1 to 8, more preferably 1 to 6, particularly preferably 1 to 4, then preferably 1 to 3, and most preferably 1 or 2 per molecule. is there.
  • Examples of the alcohol include monohydric alcohols having 10 to 16 carbon atoms, polyhydric (2 to 5 valent) alcohols having 6 to 16 carbon atoms, monohydric alcohols having 17 to 30 carbon atoms, and polyvalent alcohols having 2 to 5 carbon atoms ( (Divalent to hexavalent) alcohol, polyhydric (hexavalent) alcohol having 6 to 30 carbon atoms, and the like.
  • Examples of the monohydric alcohol having 17 to 30 carbon atoms include isooctadecyl alcohol, isoicosyl alcohol, and isotriacontyl alcohol.
  • Examples of the polyhydric (2-6 valent) alcohol having 2 to 5 carbon atoms include ethylene glycol, diethylene glycol, propylene glycol, glycerin, pentaerythritol, 1,4-butanediol and the like.
  • Examples of the polyhydric (hexavalent) alcohol having 6 to 30 carbon atoms include dipentaerythritol, tetraglycerin and sorbitol.
  • Examples of the carboxylic acid include monovalent carboxylic acids and polyvalent (divalent to hexavalent) carboxylic acids.
  • Examples of the monovalent carboxylic acid include carboxylic acids having 1 to 30 carbon atoms, and include formic acid, acetic acid, propionic acid, myristic acid, stearic acid, linoleic acid, linolenic acid, oleic acid, glycolic acid, lactic acid, and gluconic acid. Etc.
  • Examples of the polyvalent (divalent to hexavalent) carboxylic acids include carboxylic acids having 4 to 10 carbon atoms, such as succinic acid, adipic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, itaconic acid, and tartaric acid. Is mentioned.
  • Examples of the oxypropylene-containing compound include propylene oxide 1-70 mol adduct of alcohol, propylene oxide 1-70 mol adduct of carboxylic acid, and propylene oxide 1-70 mol adduct of the above oxyethylene-containing compound. it can.
  • the addition number (mol) of the propylene oxide is preferably 1 to 70, more preferably 2 to 50, particularly preferably 4 to 35, next preferably 6 to 30, and most preferably 8 to 25 in one molecule.
  • Examples of the alcohol include monohydric alcohols having 1 to 9 carbon atoms in addition to the above alcohols.
  • Examples of the monohydric alcohol having 1 to 9 carbon atoms include methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, sec-butyl alcohol, tert-butyl alcohol, n-hexanol, and n-pen.
  • Examples include butanol, 2-ethylhexanol and n-octanol.
  • esters examples include organic acids (monovalent carboxylic acids, polyvalent (2-6 valent) carboxylic acids, etc.) or inorganic acids (sulfuric acid, phosphoric acid, etc.), monohydric alcohols, polyvalent (2-6 valent) alcohols. Further, an ethylene oxide adduct of alcohol or carboxylic acid or an ester compound with a propylene oxide adduct of alcohol or carboxylic acid can be used. Examples of the ester include butyl acetate and ethylene glycol acetic acid diester. These ester compounds are not limited as long as they have at least one ester bond, and the ester contains a carboxylate group (such as an alkali metal (sodium and potassium) ion as a counter ion). Also good.
  • a carboxylate group such as an alkali metal (sodium and potassium) ion as a counter ion. Also good.
  • silicone oils, modified silicone oils, oxyethylene-containing compounds, oxypropylene-containing compounds and esters are preferred, more preferably modified silicone oils, oxyethylene-containing compounds and oxypropylene-containing compounds, particularly preferably oxypropylenes.
  • Ethylene-containing compounds and oxypropylene-containing compounds, most preferably oxyethylene-containing compounds are preferred.
  • the timing for supplying the drying aid is not particularly limited as long as it is before the step of drying the hydrogel crosslinked polymer in a stationary state. , Immediately before the polymerization step, during the polymerization step, immediately after the polymerization step, during the gel pulverization step, immediately after the gel pulverization step and immediately before the polymer drying step, preferably immediately before the polymerization step, during the polymerization step, immediately after the polymerization step, during the gel pulverization step And immediately after the gel pulverization step, more preferably immediately before the polymerization step, during the polymerization step, immediately after the polymerization step and during the gel pulverization step, and most preferably immediately before the polymerization step, immediately after the polymerization step and during the gel pulverization step.
  • the timing for supplying the drying aid is used immediately before the polymerization step, during the polymerization step, immediately after the polymerization step, and for the obtained polymer and polymerization.
  • the step of separating the organic solvent used and after the step of separating the obtained polymer and the organic solvent used for the polymerization, immediately before the polymerization step, immediately after the polymerization step, and for the obtained polymer and polymerization.
  • the step of separating the used organic solvent more preferably immediately after the polymerization step and after the step of separating the obtained polymer and the organic solvent used for the polymerization, most preferably immediately after the polymerization step.
  • the method for mixing the water-containing gel and the drying aid is not particularly limited, and may be mixed so that the drying aid is present on the surface and / or inside of the water-containing gel, and the drying aid is uniform or non-uniform. May be mixed as present.
  • the drying aid is preferably present at least on the surface of the hydrogel.
  • a method of mixing the water-containing gel and the drying aid (1) a method of adding the drying aid while stirring the water-containing gel (including spray etc., the same applies hereinafter), and (2) drying aid in advance.
  • a method of mixing the agent with the hydrous gel at a high concentration to prepare a master batch and adding the master batch to the hydrous gel so as to obtain a predetermined addition amount as a drying aid can be applied.
  • the drying aid can be added directly (in neat form such as lump, powder, liquid, etc.) or in any form of solution or dispersion, but is preferably added in the form of solution or dispersion.
  • a well-known thing can be used as a solvent or a dispersion medium used in order to set it as these forms.
  • the ratio of drying aid to solvent or dispersion medium ⁇ drying aid / solvent or dispersion medium ⁇ is not particularly limited, but is preferably 0.01 to 10/100, more preferably. 0.01 to 5/100, particularly preferably 0.05 to 5/100.
  • a dispersing agent when adding with a dispersion liquid, a dispersing agent can be used as needed and a well-known thing can be used as a dispersing agent.
  • the ratio of the drying aid to the dispersant ⁇ drying aid / dispersant ⁇ is not particularly limited, but is preferably 100 / 0.01 to 20, more preferably 100 / 0.1. To 15, particularly preferably 100/1 to 10, most preferably 100/3 to 7.
  • This step is a step of drying the particulate hydrogel crosslinked polymer obtained in the gel grinding step to obtain a dry polymer.
  • This step also includes a step of drying the polymer after supplying a drying aid to the particulate hydrogel crosslinked polymer obtained in the gel pulverization step to obtain a dry polymer.
  • the resin solid content of the dry polymer is preferably 80% by weight or more, more preferably 85% by weight or more, and more preferably 90% by weight or more from the viewpoint of easy pulverization. A solid content is particularly preferable.
  • the drying method in this drying process is not particularly limited, but heat drying, hot air drying, vacuum drying, infrared drying, microwave drying, drum dryer drying, azeotropic dehydration drying with a hydrophobic organic solvent, and high-temperature steam are used. Various drying methods such as high-humidity drying are used.
  • the conditions such as the drying method, drying temperature, and drying time are not particularly limited, and various methods and conditions can be suitably combined.
  • This step is a step of obtaining water-absorbing resin particles by pulverizing and classifying the dried polymer obtained in the drying step.
  • the (2) gel pulverization step is different from the gel pulverization step in that the resin solid content at the time of pulverization, in particular, the object to be pulverized is subjected to a drying step (preferably dried to the resin solid content).
  • the water-absorbent resin particles obtained after the pulverization step may be referred to as a pulverized product.
  • the dried polymer obtained in the drying step can be used as a water-absorbing resin as it is, but it is preferable to control to a specific particle size in order to improve physical properties in the surface crosslinking step, particularly the surface crosslinking step described later.
  • the particle size control is not limited to the main pulverization step and the classification step, and can be appropriately performed in a polymerization step, a fine powder collection step, a granulation step, and the like.
  • the pulverizer that can be used in the pulverization process is not particularly limited.
  • a vibration mill, a roll granulator, a knuckle type pulverizer, a roll mill, a high-speed rotary pulverizer (pin mill, hammer mill, screw mill), a cylinder And the like is preferable to use a multistage roll mill or roll granulator from the viewpoint of particle size control.
  • classification operation is performed so that the following particle size is obtained.
  • classification operation is preferably performed before the surface crosslinking step (first classification step), and further after surface crosslinking.
  • a classification operation (second classification step) may be performed.
  • the classification operation may employ a known method, and is not particularly limited.
  • classification is performed as follows in sieving using a sieve. That is, when the particle size distribution of the water-absorbent resin particles is set to 150 to 850 ⁇ m, for example, first, the pulverized product is sieved with a sieve having an aperture of 850 ⁇ m, and the pulverized product that has passed through the sieve has an aperture of 150 ⁇ m or 150 ⁇ m.
  • the method for producing a water-absorbent resin according to the present invention preferably further includes a surface cross-linking step in order to improve water absorption performance (water absorption against pressure, liquid permeability, water absorption rate, etc.).
  • the surface cross-linking step includes a surface cross-linking step performed using a known surface cross-linking agent and a surface cross-linking method, and further includes an addition step described later and other steps as necessary.
  • a cross-linking agent capable of reacting with a carboxyl group is preferable from the viewpoint of physical properties or handleability of the water absorbent resin.
  • a cross-linking agent capable of reacting with a carboxyl group is preferable from the viewpoint of physical properties or handleability of the water absorbent resin.
  • polyhydric alcohol compounds, epoxy compounds, polyvalent amine compounds and inorganic or organic salts thereof, polyvalent isocyanate compounds, haloepoxy compounds, polyvalent oxazoline compounds, oxazolidinone compounds, alkylene carbonate compounds (in other words, Cyclic urea compounds), oxetane compounds, polyvalent metal compounds and the like are preferred.
  • polyhydric alcohol compound examples include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, 1,3-propanediol, 1-methyl-1,3.
  • epoxy compound examples include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and glycidol. Etc.
  • polyvalent amine compound examples include ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, polyethyleneimine, and polyamidepolyamine.
  • organic salt an aziridinium salt is mentioned, for example.
  • polyvalent isocyanate compound examples include 2,4-tolylene diisocyanate and hexamethylene diisocyanate.
  • haloepoxy compound examples include epichlorohydrin, epibromohydrin, ⁇ -methylepichlorohydrin, and the like.
  • polyvalent oxazoline compound examples include 1,2-ethylenebisoxazoline.
  • oxazolidinone compound examples include N-acyl oxazolidinone and 2-oxazolidinone.
  • alkylene carbonate compound examples include 1,3-dioxolan-2-one, 4-methyl-1,3-dioxolan-2-one, 4,5-dimethyl-1,3-dioxolan-2-one, , 4-Dimethyl-1,3-dioxolan-2-one, 4-ethyl-1,3-dioxolan-2-one, 4-hydroxymethyl-1,3-dioxolan-2-one, 1,3-dioxane- 2-one, 4-methyl-1,3-dioxane-2-one, 4,6-dimethyl-1,3-dioxane-2-one, 1,3-dioxopan-2-one and the like can be mentioned.
  • oxetane compound examples include oxetane, 2-methyloxetane, 3-methyl-3-hydroxymethyloxetane, and 3-ethyl-3-hydroxymethyloxetane.
  • polyvalent metal compound examples include hydroxides or chlorides of polyvalent metals such as zinc, calcium, magnesium, aluminum, iron, and zirconium.
  • polyhydric alcohol compounds epoxy compounds, oxazolidinone compounds, alkylene carbonate compounds, and oxetane compounds are particularly preferable from the viewpoint of improving the properties of the water-absorbent resin.
  • These surface cross-linking agents may be used alone or in combination of two or more.
  • the amount of the surface cross-linking agent used is suitably determined within the range of preferably 0.001 to 10 parts by weight, more preferably 0.01 to 5 parts by weight, with respect to 100 parts by weight of the water-absorbent resin particles. Good.
  • a solvent such as water or a hydrophilic organic solvent is preferably used in accordance with the surface crosslinking agent.
  • hydrophilic organic solvent examples include lower alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, and t-butyl alcohol; ketones such as acetone; dioxane, tetrahydrofuran Ethers such as N; N-dimethylformamide and the like; sulfoxides such as dimethyl sulfoxide and the like.
  • the said hydrophilic organic solvent may be used individually by 1 type, or may use 2 or more types together.
  • the amount of the hydrophilic organic solvent used is preferably in the range of 0.1 to 10 parts by weight, more preferably in the range of 0.5 to 5 parts by weight with respect to 100 parts by weight of the water-absorbing resin particles. .
  • the amount of the hydrophilic organic solvent used is preferably 0.5 to 20 parts by weight, more preferably 1 to 10 parts by weight with respect to 100 parts by weight of the monomer.
  • the amount of the hydrophilic organic solvent is 0.001 to 10% by weight, preferably 0.003 to 1% by weight, based on 100 parts by weight of the monomer. In the range described above, a water-free fine particle powder or a surfactant may coexist.
  • the above-described surface cross-linking agent preferably the surface cross-linking agent solution is moved to the spray nozzle through the primary pressure regulating valve adjusted to a desired pressure, and sprayed from the spray nozzle, and the classification step. It supplies to the water-absorbent resin which passed through.
  • the temperature at which the surface cross-linking agent passes through the primary pressure regulating valve is preferably within the range of 10 to 90 ° C, more preferably within the range of 15 to 85 ° C, and particularly preferably within the range of 20 to 80 ° C.
  • the temperature at which the surface cross-linking agent passes through the spray nozzle is preferably within the range of 10 to 90 ° C, more preferably within the range of 15 to 85 ° C, and particularly preferably within the range of 20 to 80 ° C.
  • the surface cross-linking agent By supplying the surface cross-linking agent at a temperature within the above-described range, the surface cross-linking agent (without substantially changing the volume of the above-described member used in the primary pressure regulating valve and the spray nozzle) ( Raw material) can be supplied. Thereby, the raw material of the stable capacity
  • the surface cross-linking agent preferably the surface cross-linking agent solution is mixed with the water-absorbing resin particles, the water-absorbing resin particles are swollen by a solvent such as water in the surface cross-linking agent solution.
  • a mixing apparatus In order to mix these uniformly and reliably, it is preferable that it is an apparatus provided with big mixing force.
  • the mixing apparatus include a cylindrical mixer, a double wall conical mixer, a high-speed stirring mixer, a V-shaped mixer, a ribbon mixer, a screw mixer, a double-arm kneader, and a pulverizing mold.
  • a kneader, a rotary mixer, an airflow mixer, a turbulator, a continuous Redige mixer, a continuous prussian mixer, or the like can be preferably used.
  • These mixing devices are preferably heated by passing a heating medium through the jacket and / or the rotating shaft in order to prevent adhesion of the polymer to the device.
  • the swollen water absorbent resin particles are surface-crosslinked by heating.
  • the heating temperature is appropriately adjusted depending on the type or amount of the surface cross-linking agent and solvent.
  • the heating temperature and the heating time depend on the reactivity of the surface cross-linking agent, they are usually 90 to 250 ° C., more preferably 120 to 200 ° C., and 10 to 100 minutes, more preferably 20 Surface cross-linking reaction is carried out under conditions within a range of ⁇ 60 minutes.
  • a normal dryer or a heating furnace is used.
  • a conduction heat transfer type for example, a radiation heat transfer type, a hot air heat transfer type, a dielectric heating type dryer or a heating furnace is suitable.
  • examples of the surface cross-linking device include a groove dryer, a rotary dryer, a disk dryer, a fluidized bed dryer, an airflow dryer, and an infrared dryer.
  • a groove type dryer especially a conduction heat transfer type stirring dryer (for example, Nara Machinery Co., Ltd.
  • a fluidized bed dryer especially a heat transfer tube combined type fluidized bed dryer (for example, Okawara Seisakusho (conduction flow dryer) or fluidized bed dryer (for example, Pulbis-GB22 manufactured by Yamato Scientific Co., Ltd.) is preferably used.
  • the surface cross-linking device preferably has a rotating shaft in consideration of uniform surface treatment and the like, and a heat treatment device having a rotating shaft is particularly preferably used.
  • Addition step In the method for producing a water-absorbent resin according to the present invention, a deodorant or liquid permeability is used as necessary to improve water absorption performance (water absorption against pressure, liquid permeability, water absorption speed, etc.). An addition step of adding a function improver such as an improver is included. In addition, you may add this addition process simultaneously or separately, when adding the surface crosslinking agent mentioned above.
  • a deodorant may be added in order to add deodorant performance to the water absorbent resin.
  • the deodorant include an extract (essential oil) extracted from a plant, a plant body, a plant meal or extracted meal produced as a by-product in a plant processing step, or ketocarboxylic acid.
  • extracts (essential oils) extracted from plants include polyphenols, flavones and the like, and caffeine.
  • plant cocoons or plant cocoons produced as a by-product in the plant processing step include plants such as camellia, hikasaki, mokkok, rice, sasa, bamboo, corn, wheat, coffee, and components thereof.
  • the ketocarboxylic acid is a compound represented by the general formula “R 1 —C (O) —R 2 —COOH”.
  • R 1 is a C1-C30 alkyl group, and the alkyl group may be optionally substituted with one or more functional groups, and the alkyl group is particularly preferably one or It is preferably substituted selectively with a plurality of hydroxyl groups or carboxyl groups.
  • the R 2 may be a site that bonds the C (O) and the COOH, and the C (O) and the COOH may be directly bonded. Examples of R 2 include — (CH 2 ) n —. N is preferably 1 to 4.
  • R 1 and R 2 may be linear, branched, or cyclic.
  • ketocarboxylic acid examples include 2-oxo-L-gulonic acid (L-enantiomer of 2-oxo-3,4,5,6-tetrahydroxyhexanoic acid) and / or 2-oxo-glutaric acid ( 2-oxo-pentane-1,5-dioic acid).
  • ketocarboxylic acid solvent examples include water, a mixture of water and acetone, a mixture of water and propylene glycol, and a mixture of water and 1,3-propanediol.
  • concentration of ketocarboxylic acid in the solution is preferably within the range of 0.5 to 30% by weight, more preferably within the range of 1.0 to 20% by weight, and most preferably within the range of 2.0 to 10% by weight. preferable.
  • the temperature when these deodorizers pass through the primary pressure regulating valve and the spray nozzle is preferably within the range of 10 to 50 ° C, more preferably within the range of 15 to 45 ° C, and particularly within the range of 20 to 40 ° C. preferable.
  • the deodorant By supplying the deodorant at a temperature within the above-described range, the deodorant (without substantially changing the volume of the above-described member used in the primary pressure regulating valve and the spray nozzle ( Raw material) can be supplied. Thereby, the raw material of the stable capacity
  • liquid permeability improving agent may be added in order to improve the liquid permeability of the water absorbent resin.
  • liquid permeability improver include polycationic polymer compounds, polyvalent metal inorganic salts, and polyvalent metal organic salts.
  • the polycationic polymer compound is not particularly limited, but the cationic polymer compound disclosed in US Pat. No. 5,382,610, US Pat. No. 7098284, WO2009 / 110645, WO2009 / 041731, and WO2009 / 041727 is used. It can be preferably used. Among these, polyethyleneimine, polyvinylamine, polyallylamine, and a dimethylamine / ammonia / epichlorohydrin condensate are preferable.
  • Examples of the inorganic salt of the polyvalent metal include aluminum sulfate, aluminum chloride, zirconium chloride oxide, zirconium carbonate ammonium, zirconium carbonate potassium, zirconium carbonate potassium, zirconium sulfate, zirconium acetate, zirconium nitrate and the like.
  • organic salt of the polyvalent metal examples include aluminum acetate, aluminum lactate, hydroxy zirconium chloride, titanium triethanolamate, and titanium lactate.
  • the temperature at which these liquid permeability improvers pass through the primary pressure regulating valve and the spray nozzle is preferably in the range of 20 to 40 ° C.
  • the above-described liquid permeability can be achieved without substantially changing the volume of the above-described member used in the primary pressure regulating valve and the spray nozzle.
  • a property improver raw material
  • capacitance can be supplied.
  • the fine powder recycling step can be included as necessary.
  • the fine powder recycling step is a state in which the fine powder of the water absorbent resin generated in the drying step, the pulverization step and the classification step (particularly, the fine powder containing 70% by weight or more of the powder having a particle diameter of 150 ⁇ m or less) is separated as it is. Or the process which hydrates and recycles to a polymerization process or a drying process.
  • oxidants antioxidants, water, polyvalent metal compounds, water-insoluble inorganic or organic powders such as silica and metal soap, antibacterial agents, polymer polyamines, pulp and thermoplastic fibers are added. May be.
  • the method for producing a water-absorbent resin according to the present invention a member having a volume change rate within a specific range when immersed in a measurement raw material whose temperature is adjusted to 25 ° C. for one week is used. Even if it contacts the raw material of the conductive resin, since the member whose volume does not easily change compared to the members used conventionally is used in the manufacturing apparatus, the raw material can be continuously supplied with a stable capacity. Therefore, the method for producing a water absorbent resin according to the present invention is a method capable of continuously producing a water absorbent resin having uniform quality.
  • the method for producing a water-absorbent resin according to the present invention continuously applies a water-absorbent resin having various performances (in particular, CRC (water absorption capacity under no pressure), SFC (saline flow inductivity)) stable. It is a method that can be manufactured.
  • CRC water absorption capacity under no pressure
  • SFC saline flow inductivity
  • the use of the water-absorbent resin in the present invention is not particularly limited, but is preferably used for absorbent articles for sanitary products such as paper diapers, sanitary napkins, and incontinence pads. Can be done.
  • the water-absorbent resin in the present invention is used as an absorbent for high-concentration paper diapers (a large amount of water-absorbent resin used per one paper diaper), which has been a problem with odor and coloring derived from raw materials. be able to.
  • the water-absorbent resin in the present invention can be expected to have a remarkable effect when used in the upper layer portion of the absorber.
  • the content (core concentration) of the water-absorbent resin in the absorbent body is preferably in the range of 30 to 100% by weight, more preferably in the range of 40 to 100% by weight, and in the range of 50 to 100% by weight. Is more preferably within the range of 60 to 100% by weight, particularly preferably within the range of 70 to 100% by weight, and most preferably within the range of 75 to 95% by weight.
  • the absorbent article When the core concentration is within the above range, when the absorbent body is used in the upper layer portion of the absorbent article, the absorbent article can maintain a clean white state. Furthermore, since the diffusibility of body fluids such as urine and blood is excellent, an improvement in absorption can be expected by efficient liquid distribution.
  • SFC saline flow inductivity
  • SFC in this invention refers to the liquid permeability of the 0.69 weight% sodium chloride aqueous solution with respect to the water absorbing resin under a load of 2.07 kPa.
  • (C) Immersion test In the immersion test in the present invention, first, the volume of each measurement member before immersion is calculated. The volume of the measurement member is calculated from the increased volume by introducing the measurement member into water adjusted to 25 ° C. poured into a polypropylene container. Then, a measurement member is immersed in the liquid raw material of each water absorbent resin adjusted to 25 degreeC.
  • the container used for the immersion test is made of a material that is not dissolved by the liquid raw material used, has a shape that can completely accommodate the measurement member, has a structure that can be sealed, and has a volume that is at least 10 times that of the measurement member. That's fine.
  • the said container should just be a container which can perform an immersion test, without cut
  • the material for the container include glass, stainless steel, and polypropylene. In the case where there is a risk of dissolution by the liquid raw material used by the container, a stainless steel container, a glass container, or the like can be used as the container.
  • a small member such as a nozzle cushion is filled with 100 ml of a liquid raw material in a 125 mL pack ace (Teraoka Co., Ltd., polypropylene container), and each member is immersed in a sealed state for one week.
  • a raw material having a melting point of 25 ° C. or higher is adjusted to a temperature of the melting point of the raw material plus 10 ° C., and the same immersion test is performed.
  • Example 1 Member immersion test 1
  • a nozzle cushion manufactured by Ikeuchi Co., Ltd., empty conical nozzle K140, fine mist generation minimum injection type
  • main material polytetrafluoroethylene (PTFE)
  • PTFE polytetrafluoroethylene
  • a surface cross-linking agent solution having a composition ratio of ethylene carbonate (EC): 1,2-propylene glycol (PG): water (W) 0.5: 0.5: 3.0 was used. .
  • the volume of the nozzle cushion before being immersed in the surface cross-linking agent was 93 [mm 3 ].
  • the volume of the nozzle cushion after being immersed in the surface cross-linking agent was 95 [mm 3 ].
  • the volume of the nozzle cushion increased by being immersed in the surface cross-linking agent was 2 [mm 3 ], and the volume change rate of the nozzle cushion was 2 [%]. The results are shown in Table 1.
  • the nozzle cushion whose main material is PTFE is a member capable of stably and continuously supplying the surface cross-linking agent since its volume is hardly changed even when immersed in the surface cross-linking agent.
  • Example 2 Member immersion test 2
  • a closer whose main material is ceramic manufactured by Ikeuchi Co., Ltd., an empty conical nozzle K140, a component in a fine mist generating minimum injection amount
  • a closer whose main material is ceramic manufactured by Ikeuchi Co., Ltd., an empty conical nozzle K140, a component in a fine mist generating minimum injection amount
  • the volume of the closer before being immersed in the surface cross-linking agent was 97 [mm 3 ].
  • the volume of the closer after being immersed in the surface cross-linking agent was 99 [mm 3 ].
  • the volume of the closer increased by being immersed in the surface cross-linking agent was 2 “mm 3 ”, and the volume change rate of the closer was 2 [%]. The results are shown in Table 1.
  • a closer whose main material is ceramic is a member that can be stably and continuously supplied with the surface cross-linking agent since the volume hardly changes even when immersed in the surface cross-linking agent.
  • Nozzle cushion made by Ikeuchi Co., Ltd., empty conical nozzle K140, part in the fine mist generating minimum injection amount
  • a surface cross-linking agent similar to that of Example 1 for one month at 30 ° C. for one month. Soaked.
  • the volume of the nozzle cushion before being immersed in the surface cross-linking agent was 93 [mm 3 ].
  • the volume of the nozzle cushion after being immersed in the surface cross-linking agent was 112 [mm 3 ].
  • the volume of the nozzle cushion increased by being immersed in the surface cross-linking agent was 19 [mm 3 ], and the volume change rate of the nozzle cushion was 20 [%]. The results are shown in Table 1.
  • the nozzle cushion whose main material is fluororubber changes its volume when immersed in the surface cross-linking agent, so that it can be understood that the surface cross-linking agent cannot be stably supplied continuously.
  • Example 3 Member immersion test 3
  • a surface cross-linking agent used in the surface cross-linking step a nozzle cushion whose main material is polytetrafluoroethylene (PTFE) (manufactured by Ikeuchi Co., Ltd., an empty conical nozzle K140, a component in the fine mist generating minimum injection amount form) at 30 ° C. Soaked for 1 month.
  • PTFE polytetrafluoroethylene
  • PG 1,2-propylene glycol
  • W water
  • the volume of the nozzle cushion before being immersed in the surface cross-linking agent was 93 [mm 3 ].
  • the volume of the nozzle cushion after being immersed in the surface cross-linking agent was 95 [mm 3 ].
  • the volume of the nozzle cushion increased by being immersed in the surface cross-linking agent was 2 [mm 3 ], and the volume change rate of the nozzle cushion was 2 [%]. The results are shown in Table 1.
  • the nozzle cushion whose main material is PTFE is a member capable of stably and continuously supplying the surface cross-linking agent since its volume is hardly changed even when immersed in the surface cross-linking agent.
  • Example 4 Member immersion test 4
  • a closer made by Ikeuchi Co., Ltd., empty conical nozzle K140, a component in the fine mist generation minimum injection form
  • a surface cross-linking agent similar to Example 3 at 30 ° C. for one month.
  • the volume of the closer before being immersed in the said surface crosslinking agent was 98 [mm ⁇ 3 >].
  • the volume of the closer after being immersed in the surface cross-linking agent was 99 [mm 3 ].
  • the volume of the closer increased by being immersed in the surface cross-linking agent was 1 [mm 3 ], and the volume change rate of the closer was 1 [%]. The results are shown in Table 1.
  • a closer whose main material is ceramic is a member that can be stably and continuously supplied with the surface cross-linking agent since the volume hardly changes even when immersed in the surface cross-linking agent.
  • Nozzle cushion made by Ikeuchi Co., Ltd., empty conical nozzle K140, part in the fine mist generation minimum injection amount
  • a surface cross-linking agent similar to that used in Example 3 for one month at 30 ° C. Soaked.
  • the volume of the nozzle cushion before being immersed in the surface cross-linking agent was 93 [mm 3 ].
  • the volume of the nozzle cushion after being immersed in the surface cross-linking agent was 109 [mm 3 ].
  • the volume of the nozzle cushion increased by being immersed in the surface cross-linking agent was 16 [mm 3 ], and the volume change rate of the nozzle cushion was 17 [%]. The results are shown in Table 1.
  • the nozzle cushion whose main material is fluororubber changes its volume when immersed in the surface cross-linking agent, so that it can be understood that the surface cross-linking agent cannot be stably supplied continuously.
  • V # 7010 (Japan) is the main material of polytetrafluoroethylene (PTFE) in ethylene carbonate (manufactured by Toa Gosei Co., Ltd., purity 99.0% or more) used as an internal cross-linking agent in the polymerization step or a surface cross-linking agent in the surface cross-linking step.
  • PTFE polytetrafluoroethylene
  • ethylene carbonate manufactured by Toa Gosei Co., Ltd., purity 99.0% or more
  • VALFLON Gasket VALFLON Gasket
  • FIG. 3 shows V # 7010 used in this example.
  • the volume of V # 7010 before being immersed in ethylene carbonate was 9740 [mm 3 ].
  • the volume of V # 7010 after being immersed in ethylene carbonate was 9740 [mm 3 ].
  • the results are shown in Table 1.
  • V # 7010 the main material of which is PTFE, does not change in volume even when immersed in ethylene carbonate, so that it can be seen that it is a member that can supply ethylene carbonate stably and continuously.
  • Example 3 A nozzle cushion (manufactured by Ikeuchi Co., Ltd., empty cone nozzle K140 fine mist generation minimum injection amount) made of fluororubber was immersed in ethylene carbonate similar to Example 5 at 70 ° C. for 9 days.
  • the volume of the nozzle cushion before being immersed in ethylene carbonate was 93 [mm 3 ].
  • the volume of the nozzle cushion after being immersed in ethylene carbonate was 141 [mm 3 ].
  • the volume of the nozzle cushion increased by being immersed in ethylene carbonate was 48 [mm 3 ], and the volume change rate of the nozzle cushion was 52 [%]. The results are shown in Table 1.
  • the nozzle cushion the main material of which is fluororubber, is a member that cannot stably supply ethylene carbonate because its volume changes when immersed in ethylene carbonate.
  • V # 7030 center material (Nippon VALQUA INDUSTRY CO., LTD., VALFLON jacket gasket) whose main material is aramid fiber and rubber was immersed in the same ethylene carbonate as in Example 5 at 70 ° C. for 1 month.
  • FIG. 4 shows V # 7030 used in this comparative example.
  • (a) is a view of V # 7030 viewed from the top
  • (b) is a view of V # 7030 viewed from the arrow direction (lateral direction) of (a)
  • (c) is V It is the figure which represented the cross section of # 7030 typically.
  • the volume of the V # 7030 center material before being immersed in ethylene carbonate was 3965 [mm 3 ].
  • the volume of the V # 7030 center material after being immersed in ethylene carbonate was 4643 [mm 3 ].
  • the volume of the V # 7030 center material increased by being immersed in ethylene carbonate was 678 [mm 3 ], and the volume change rate of the V # 7030 center material was 17%.
  • Table 1 The results are shown in Table 1.
  • the V # 7030 center material the main material of which is aramid fiber and rubber, is a member that cannot stably supply ethylene carbonate because its volume changes when immersed in ethylene carbonate.
  • Example 6 Production 1 of water absorbent resin
  • SUS as the main material of the pressure regulating valve seat of the primary pressure regulating valve
  • PTFE as the cushioning material for the spray nozzle
  • ceramics as the closer for supplying the surface crosslinking agent in the surface crosslinking step. It is shown below.
  • a water-absorbent resin production device As a water-absorbent resin production device, metering pump, mixing device, belt polymerization machine, gel pulverizer, belt dryer, powder pulverizer, classifier, high-speed continuous mixer (mixer of surface cross-linking agent), heat treatment machine, A continuous production apparatus in which various devices such as a cooling machine were connected to each other by a transporter including a pipe was used.
  • a production method including a polymerization step, a gel pulverization step, a drying step, a pulverization step, a classification step, a surface crosslinking step, an addition step, a rehumidification step, a transport step, and a storage step.
  • a water absorbent resin was continuously produced.
  • the production capacity of the continuous production apparatus was 3000 [Kg / hr]. Details of the manufacturing method will be described below. Note that each of the above steps can be performed in one series, or in two or more series. When performing in two or more series, the production capacity is indicated by the total amount of each series.
  • Acrylic acid 2500 [kg / h], 48.5 wt% sodium hydroxide aqueous solution 2050 [kg / h], polyethylene glycol diacrylate (average number of added moles of ethylene oxide: n 9) 15 [kg / h], and 2 0.0 wt% diethylenetriamine-N, N, N ′, N ′′, N ′′ -5 acetic acid trisodium salt aqueous solution 60 [kg / h] was continuously supplied to the mixing apparatus and mixed to obtain a mixture continuously. It was.
  • the temperature of the mixture is adjusted to 80 ° C., 4% sodium persulfate aqueous solution 110 [kg / h] is mixed, and the thickness is set to about 20 mm on a flat belt polymerization machine in a nitrogen atmosphere.
  • the above mixture was continuously fed using a metering pump.
  • polymerization (polymerization time: 10 minutes) was continuously performed at 110 ° C. to obtain a hydrogel crosslinked polymer.
  • the hydrogel crosslinked polymer was continuously crushed into particles having a diameter of about 1 mm using a gel grinder connected to the belt polymerizer.
  • the coarsely crushed hydrogel crosslinked polymer was continuously supplied on a perforated plate provided in a belt dryer so as to have a thickness of 3 to 5 cm.
  • Hot air with a dew point of 60 ° C. and a temperature of 170 ° C. was passed through the belt dryer in the vertical direction, and the hydrogel crosslinked polymer was continuously dried with hot air for 30 minutes, and blocked at the end of the belt dryer. A dried product of the water-absorbent resin was obtained.
  • the dried product of the block-shaped water absorbent resin was taken out from the belt dryer and crushed to obtain a dried product of particulate water absorbent resin.
  • the obtained dried product 300 [kg / hr] was continuously supplied to a three-stage roll granulator (roll gap is 1.0 mm, 0.55 mm, 0.42 mm) (powder pulverizer) and pulverized, A powdery water absorbent resin was obtained.
  • the obtained powdery water-absorbing resin was continuously classified at about 60 ° C. using a JIS standard sieve (classifier) having openings of 850 ⁇ m and 150 ⁇ m, and particles larger than 850 ⁇ m and particles smaller than 150 ⁇ m were obtained. Removed.
  • a water-absorbent resin (1) in which 90% by mass or more of the particles had a size of 150 ⁇ m or more and 850 ⁇ m or less was obtained.
  • the water-absorbent resin (1) after mixing the surface cross-linking agent aqueous solution was continuously heat-treated at 195 ° C. for 40 minutes with a heat treatment machine (paddle dryer). After the heat treatment, the water absorbent resin (1) was put into a cooler (paddle cooler) at 60 ° C. and cooled for 40 minutes.
  • a spray nozzle manufactured by Ikeuchi Co., Ltd., product number: K120S303W, using polytetrafluoroethylene (PTFE) as the main material of the nozzle cushion
  • the water-absorbent resin (1) was passed through a JIS standard sieve having an aperture of 850 ⁇ m to continuously produce water-absorbent resin particles having a uniform size.
  • Example 5 The primary pressure regulating valve used in the surface cross-linking step of Example 6 was changed. That is, in the surface cross-linking step of Example 6 above, Example 1 was used except that a primary pressure regulating valve (Nakakita Seisakusho Co., Ltd., product number: NS75RF, fluorine rubber was used as the main material of the pressure regulating valve seat) was used. The same operation was performed to continuously produce water absorbent resin particles.
  • a primary pressure regulating valve Neakakita Seisakusho Co., Ltd., product number: NS75RF, fluorine rubber was used as the main material of the pressure regulating valve seat
  • Example 6 The spray nozzle used in the surface cross-linking step of Example 6 was changed. That is, in the surface cross-linking step of Example 6 above, water-absorbent resin particles were continuously produced by performing the same operation as in Example 6 except that fluororubber was used as the cushioning material for the spray nozzle.
  • the volume of the pressure regulating valve sealing material before being immersed in the internal crosslinking agent was 226 [mm 3 ].
  • the volume of the pressure regulating valve sealing material after being immersed in the internal cross-linking agent was 343 [mm 3 ].
  • the volume of the pressure regulating valve sealing material increased by being immersed in the internal cross-linking agent was 117 [mm 3 ], and the volume change rate of the pressure regulating valve sealing material was 52 [%].
  • Table 1 The results are shown in Table 1.
  • the pressure regulating valve seal material whose main material is fluororubber is a member that cannot stably supply the internal cross-linking agent because the volume changes when immersed in the internal cross-linking agent. .
  • a pressure-regulating valve seal material whose main material is fluororubber is used in ethylene glycol diglycidyl ether (Nagase Chemtex EX-810, epoxy equivalents 108 to 118) used as an internal crosslinking agent in the polymerization process or as a surface crosslinking agent in the surface crosslinking process. Immersion at 25 ° C. for 1 week.
  • the volume of the pressure regulating valve sealing material before being immersed in ethylene glycol diglycidyl ether was 228 [mm 3 ].
  • the volume of the pressure regulating valve sealing material after being immersed in ethylene glycol diglycidyl ether was 364 [mm 3 ].
  • the volume of the pressure regulating valve sealing material increased by being immersed in ethylene glycol diglycidyl ether was 136 [mm 3 ], and the volume change rate of the pressure regulating valve sealing material was 60 [%].
  • Table 1 The results are shown in Table 1.
  • the pressure control valve seal material is a member that cannot stably supply ethylene glycol diglycidyl ether because its volume changes when immersed in ethylene glycol diglycidyl ether. I understand.
  • Example 7 A pressure-regulating valve seal material (made by Viton, FKM rubber), the main material of which is fluoro rubber, is added to the chelating agent (46 wt% diethylenetriaminepentaacetic acid trisodium aqueous solution) used in the polymerization process at 25 ° C. for 1 month. Soaked.
  • the chelating agent 46 wt% diethylenetriaminepentaacetic acid trisodium aqueous solution
  • the volume of the pressure regulating valve sealing material before being immersed in the chelating agent was 226 [mm 3 ]. Even when immersed in the chelating agent, there was no change in the volume of the pressure regulating valve seal material. Therefore, the volume change rate of the pressure regulating valve seal material was 0 [%]. The results are shown in Table 1.
  • the pressure regulating valve sealing material whose main material is fluororubber is a member that can supply the chelating agent stably and continuously because the volume does not change even when immersed in the chelating agent. .
  • Example 8 Pressure control valve seal material (made by Viton, FKM rubber) whose main material is fluoro rubber is used as a polymerization initiator (25% sodium persulfate aqueous solution) used in the polymerization process at 25 ° C. for one month. Soaked.
  • the volume of the pressure regulating valve sealing material before being immersed in the polymerization initiator was 226 [mm 3 ]. Even when immersed in the polymerization initiator, there was no change in the volume of the pressure regulating valve sealing material, and therefore the volume change rate of the pressure regulating valve sealing material was 0%. The results are shown in Table 1.
  • the pressure-regulating valve sealing material whose main material is fluororubber is a member that can stably supply the polymerization initiator because the volume does not change even when immersed in the polymerization initiator. I understand.
  • Example 9 A deodorant (green tea dry extract (manufactured by Shiraimatsu Co., Ltd., FS80MO)) used in the addition process is mixed with a pressure regulating valve seal material (manufactured by Viton Co., Ltd., FKM rubber) whose main material is fluoro rubber at 25 ° C for one month. It was immersed in between.
  • a deodorant green tea dry extract (manufactured by Shiraimatsu Co., Ltd., FS80MO) used in the addition process is mixed with a pressure regulating valve seal material (manufactured by Viton Co., Ltd., FKM rubber) whose main material is fluoro rubber at 25 ° C for one month. It was immersed in between.
  • the volume of the pressure regulating valve sealing material before being immersed in the deodorant was 226 [mm 3 ]. Even when immersed in the deodorant, there was no change in the volume of the pressure regulating valve sealing material. Therefore, the volume change rate of the pressure regulating valve sealing material was 0 [%]. The results are shown in Table 1.
  • the pressure regulating valve seal material whose main material is fluororubber is a member that can stably supply the deodorant because the volume does not change even when immersed in the deodorant. I understand.
  • a pressure-regulating valve seal material (Viton, FKM rubber), the main material of which is fluoro rubber, is added to a liquid permeability improver (50% aluminum sulfate aqueous solution (16 hydrate)) used in the addition step at 30 ° C. Soaked for 1 month.
  • the volume of the pressure regulating valve sealing material before being immersed in the liquid permeability improver was 226 [mm 3 ]. Even when immersed in the liquid permeability improver, there was no change in the volume of the pressure regulating valve sealing material. Therefore, the volume change rate of the pressure regulating valve sealing material was 0%. The results are shown in Table 1.
  • the liquid permeability improver can be stably and continuously supplied. It turns out that it is a member.
  • the water-absorbent resin produced by the production method according to the present invention is useful for sanitary goods such as paper diapers, sanitary napkins and medical blood-collecting agents.
  • absorbent articles such as pet urine absorbent, urine gelling agent for portable toilets, freshness maintaining agents such as fruits and vegetables, drip absorbent for meat and seafood, water retention agents for plants and soil (water retention agents for agriculture and horticulture), Or it can also be used for various uses, such as a cold insulating agent, a disposable warmer, a gelling agent for batteries, an anti-condensation agent, an industrial water-stopping material and packing agent, and artificial snow.

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Abstract

　L'invention porte sur un procédé de production d'une résine absorbant de l'eau, qui permet de fournir en continu d'une manière stable la matière première de la résine absorbant l'eau. Dans le procédé de production d'une résine absorbant de l'eau, un élément est utilisé, qui dans l'essai après immersion présente un changement de volume compris dans une plage de -5 à +5 % dans au moins des pièces mobiles, des sites en contact avec des pièces mobiles, ou des pièces mobiles et des sites en contact avec des pièces mobiles, ces pièces étant en contact avec la matière première, la solution de la matière première, ou la matière première et la solution de la matière première de la résine absorbant de l'eau.
PCT/JP2014/072619 2013-08-28 2014-08-28 Procédé de production d'une résine absorbant de l'eau WO2015030128A1 (fr)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024210144A1 (fr) * 2023-04-03 2024-10-10 株式会社日本触媒 Résine absorbant l'eau à base (de sel) d'acide poly(méth)acrylique, et article absorbant

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102086052B1 (ko) 2016-12-27 2020-03-06 주식회사 엘지화학 고흡수성 수지 및 이의 제조 방법
KR102616695B1 (ko) * 2018-12-11 2023-12-20 주식회사 엘지화학 고흡수성 수지 및 이의 제조 방법
KR102634904B1 (ko) 2019-09-18 2024-02-07 주식회사 엘지화학 고흡수성 수지 및 이의 제조 방법
KR102625756B1 (ko) * 2019-09-18 2024-01-16 주식회사 엘지화학 고흡수성 수지 및 이의 제조 방법

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6055002A (ja) * 1983-09-07 1985-03-29 Nippon Shokubai Kagaku Kogyo Co Ltd 新規連続重合方法
JPH0249002A (ja) * 1988-05-23 1990-02-19 Nippon Shokubai Kagaku Kogyo Co Ltd 親水性重合体の製造方法
JPH08165303A (ja) * 1994-12-16 1996-06-25 Nippon Shokubai Co Ltd 含水ゲル状架橋重合体粒子の製造装置及び製造方法
JP2003081425A (ja) * 2001-09-17 2003-03-19 Zuiko Corp 材料供給装置
JP2006199862A (ja) * 2005-01-21 2006-08-03 Nippon Shokubai Co Ltd 吸水性樹脂の製造方法
JP2010531366A (ja) * 2007-06-27 2010-09-24 株式会社日本触媒 吸水性樹脂の製造方法
WO2011040575A1 (fr) * 2009-09-30 2011-04-07 株式会社日本触媒 Résine absorbant l'eau à base d'un sel d'acide polyacrylique et son procédé de production
WO2013073682A1 (fr) * 2011-11-16 2013-05-23 株式会社日本触媒 Procédé de production de résine absorbant l'eau à base d'acide (sel) polyacrylique

Family Cites Families (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4755562A (en) 1986-06-10 1988-07-05 American Colloid Company Surface treated absorbent polymers
US4734478A (en) 1984-07-02 1988-03-29 Nippon Shokubai Kagaku Kogyo Co., Ltd. Water absorbing agent
US4625001A (en) * 1984-09-25 1986-11-25 Nippon Shokubai Kagaku Kogyo Co., Ltd. Method for continuous production of cross-linked polymer
US4783510A (en) 1986-06-04 1988-11-08 Taiyo Fishery Co., Ltd. Process for improving a water absorbent polyacrylic acid polymer and an improved polymer produced by said process
DE4020780C1 (fr) 1990-06-29 1991-08-29 Chemische Fabrik Stockhausen Gmbh, 4150 Krefeld, De
TW241279B (fr) 1991-02-01 1995-02-21 Catalyst co ltd
DE4333056C2 (de) 1993-09-29 1998-07-02 Stockhausen Chem Fab Gmbh Pulverförmige, wäßrige Flüssigkeiten absorbierende Polymere, Verfahren zu ihrer Herstellung und ihre Verwendung als Absorptionsmittel
US5610208A (en) 1994-02-17 1997-03-11 Nippon Shokubai Co., Ltd. Water-absorbent agent, method for production thereof, and water-absorbent composition
US6228930B1 (en) 1997-06-18 2001-05-08 Nippon Shokubai Co., Ltd. Water-absorbent resin granule-containing composition and production process for water-absorbent resin granule
DE19807502B4 (de) 1998-02-21 2004-04-08 Basf Ag Verfahren zur Nachvernetzung von Hydrogelen mit 2-Oxazolidinonen, daraus hergestellte Hydrogele und deren Verwendung
US6265488B1 (en) 1998-02-24 2001-07-24 Nippon Shokubai Co., Ltd. Production process for water-absorbing agent
EP0940149A1 (fr) 1998-03-04 1999-09-08 Nippon Shokubai Co., Ltd. Agent d'absorption d'eau et son procédé de production
JPH11279287A (ja) 1998-03-31 1999-10-12 Nippon Shokubai Co Ltd 吸水剤組成物および吸水剤の製造方法
JP4141526B2 (ja) 1998-04-07 2008-08-27 株式会社日本触媒 吸水性樹脂の製造方法
JP2000017004A (ja) 1998-04-28 2000-01-18 Nippon Shokubai Co Ltd 吸水性樹脂の連続製造装置
DE19849499A1 (de) 1998-10-27 2000-05-04 Basf Ag Verfahren zur vollständigen Trocknung von Hydrogelen
EP0999238B1 (fr) 1998-11-05 2008-07-09 Nippon Shokubai Co., Ltd. Résine absorbant l'eau et procédé pour sa fabrication
DE19854573A1 (de) 1998-11-26 2000-05-31 Basf Ag Verfahren zur Nachvernetzung von Hydrogelen mit 2-Oxo-tetrahydro-1,3-oxazinen
DE19854574A1 (de) 1998-11-26 2000-05-31 Basf Ag Verfahren zur Nachvernetzung von Hydrogelen mit N-Acyl-2-Oxazolidinonen
US6239230B1 (en) 1999-09-07 2001-05-29 Bask Aktiengesellschaft Surface-treated superabsorbent polymer particles
US6817557B2 (en) 2000-01-20 2004-11-16 Nippon Shokubai Co., Ltd. Process for transporting, storing, and producing a particulate water-absorbent resin
EP1130045B2 (fr) 2000-02-29 2015-10-28 Nippon Shokubai Co., Ltd. Procédé de préparation d'une poudre de résine absorbant l'eau
US6809158B2 (en) 2000-10-20 2004-10-26 Nippon Shokubai Co., Ltd. Water-absorbing agent and process for producing the same
US7312278B2 (en) 2001-06-08 2007-12-25 Nippon Shokubai Co., Ltd. Water-absorbing agent and production process therefor, and sanitary material
EP1462473B1 (fr) * 2003-03-14 2011-07-06 Nippon Shokubai Co., Ltd. Procédé pour la réticulation de la surface d'une poudre de résine absorbant l'eau
EP2156850A1 (fr) 2003-08-27 2010-02-24 Nippon Shokubai Co., Ltd. Procédé de fabrication d'une résine hygroscopique à particules à surface traitée
DE10340253A1 (de) 2003-08-29 2005-03-24 Basf Ag Sprühpolymerisationsverfahren
AU2005285763A1 (en) 2004-09-24 2006-03-30 Nippon Shokubai Co., Ltd. Particulate water-absorbing agent containing water-absorbent resin as a main component
JP4681289B2 (ja) 2004-12-02 2011-05-11 サンダイヤポリマー株式会社 吸水性樹脂の製造法
EP1824910A2 (fr) 2004-12-10 2007-08-29 Nippon Shokubai Co.,Ltd. Procede de fabrication d'une resine modifiee absorbant l'eau
CN101050244A (zh) * 2006-04-07 2007-10-10 张超 一种高吸水树脂的生产方法及聚合反应器
JP5355419B2 (ja) 2007-01-16 2013-11-27 ビーエーエスエフ ソシエタス・ヨーロピア 気相中の液滴の重合によるポリマー粒子を製造する方法
CN102056968B (zh) 2008-06-13 2013-07-03 巴斯夫欧洲公司 连续热二次表面交联吸水性聚合物颗粒的方法
JP5619010B2 (ja) * 2009-08-27 2014-11-05 株式会社日本触媒 ポリアクリル酸（塩）系吸水性樹脂およびその製造方法
EP3115382B1 (fr) 2010-04-07 2019-07-10 Nippon Shokubai Co., Ltd. Procédé de production de poudre de résine d'acide polyacrylique absorbant l'eau (sel), et poudre de résine d'acide polyacrylique absorbant l'eau (sel)

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6055002A (ja) * 1983-09-07 1985-03-29 Nippon Shokubai Kagaku Kogyo Co Ltd 新規連続重合方法
JPH0249002A (ja) * 1988-05-23 1990-02-19 Nippon Shokubai Kagaku Kogyo Co Ltd 親水性重合体の製造方法
JPH08165303A (ja) * 1994-12-16 1996-06-25 Nippon Shokubai Co Ltd 含水ゲル状架橋重合体粒子の製造装置及び製造方法
JP2003081425A (ja) * 2001-09-17 2003-03-19 Zuiko Corp 材料供給装置
JP2006199862A (ja) * 2005-01-21 2006-08-03 Nippon Shokubai Co Ltd 吸水性樹脂の製造方法
JP2010531366A (ja) * 2007-06-27 2010-09-24 株式会社日本触媒 吸水性樹脂の製造方法
WO2011040575A1 (fr) * 2009-09-30 2011-04-07 株式会社日本触媒 Résine absorbant l'eau à base d'un sel d'acide polyacrylique et son procédé de production
WO2013073682A1 (fr) * 2011-11-16 2013-05-23 株式会社日本触媒 Procédé de production de résine absorbant l'eau à base d'acide (sel) polyacrylique

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024210144A1 (fr) * 2023-04-03 2024-10-10 株式会社日本触媒 Résine absorbant l'eau à base (de sel) d'acide poly(méth)acrylique, et article absorbant

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JP5989912B2 (ja) 2016-09-07
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CN105452303A (zh) 2016-03-30
JPWO2015030128A1 (ja) 2017-03-02

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