JP2006077379A - Dispersant for papermaking - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a synthetic fiber dispersant for papermaking, which exhibits excellent dispersion stability of fibers in producing a nonwoven fabric by a papermaking method and provides a high-quality nonwoven fabric. <P>SOLUTION: The dispersant for hydrophobic fiber papermaking comprises (A) an ethylene oxide adduct of trimethylolpropane having 5,000-12,000 weight-average molecular weight and (B) an anionic surfactant composed of (B1) a 12-22C fatty acid soap and/or (B2) a metal phosphate of an 8-22C higher alcohol in a mass ratio of (A)/(B) of 40/60-90/10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a synthetic fiber oil for papermaking. More specifically, the present invention relates to a synthetic fiber dispersant used in a papermaking process of a fibrous material for papermaking containing a hydrophobic synthetic fiber.

In recent years, nonwoven fabrics made of hydrophobic synthetic fibers such as polyolefin fibers and polyester fibers have attracted attention. In order to improve the dispersibility of fibers in water when this is produced by a papermaking method, for example, a copolymer derivative of ethylene oxide and propylene oxide has been proposed as a papermaking oil for polyester fibers (Patent Document 1). A combined use of polyoxypropylene hydrocarbon ether and a nonionic surfactant has been proposed as a fiber treatment agent for wet nonwoven fabrics (Patent Document 2).
Japanese Patent Publication No.62-49394 Japanese Patent Laid-Open No. 03-193997

However, when these oil agents are used, the penetration of the oil agent emulsion between the fibers is insufficient, the dispersibility of the fibers in water is not sufficient, and the quality of the nonwoven fabric may be deteriorated. For this reason, there has been a demand for a papermaking oil having good dispersibility in order to improve the quality of nonwoven fabrics.
The object of the present invention is to exhibit excellent fiber dispersion stability when producing a nonwoven fabric made of synthetic fiber as a raw material by a papermaking method, and also has good wettability and high quality for hydrophobic fibers. An object of the present invention is to provide an oil agent for papermaking from which a nonwoven fabric can be obtained.

The inventors of the present invention have reached the present invention as a result of intensive studies to solve the above problems.
That is, the present invention comprises a mono fatty acid ester compound (A) of an ethylene oxide adduct of trimethylolpropane having a weight average molecular weight of 5000 to 12000 and an anionic surfactant (B), and the masses of (A) and (B). Hydrophobic fiber papermaking dispersant characterized in that the ratio [(A) / (B)] is 40/60 to 90/10; 0.05 to 2 Synthetic fibers for papermaking obtained by adhering to mass%; the present invention relates to a nonwoven fabric obtained by papermaking the synthetic fibers.

  The papermaking dispersant of the present invention has the effect of improving the dispersion stability of the synthetic fiber in water and imparting good wettability to the papermaking synthetic fiber as compared with conventional dispersants.

The mono-fatty acid ester compound (A) of trimethylolpropane ethylene oxide adduct, which is a component constituting the dispersant for hydrophobic fiber papermaking of the present invention, is obtained by adding ethylene oxide (hereinafter abbreviated as EO) to trimethylolpropane (A1). ) Is monoesterified. (A) is a monoester compound of (A1), and examples of fatty acids constituting (A) include fatty acids having 12 to 22 carbon atoms, which may be linear or branched, and saturated or unsaturated. Any of them may be used, and specific examples thereof include lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, linolenic acid, ricinoleic acid and behenic acid.
Of these, preferred are palmitic acid, stearic acid, and behenic acid, and more preferred is stearic acid.

  The weight average molecular weight of (A) is usually in the range of 5000 to 12000, but the preferred molecular weight range is 8000 to 11000, and the more preferred molecular weight range is 9000 to 10,000. If the weight average molecular weight of (A) is 5000 or more, the dispersing performance of the dispersant is good, and if it is 12000 or less, the stability of the dispersant is good.

Specific examples of (A) include trimethylolpropane having a weight average molecular weight of 6000 (hereinafter abbreviated as TMP) EO adduct monostearate, weight average molecular weight 10,000 TMP · EO adduct monostearate, weight Monostearic acid ester of TMP / EO adduct having an average molecular weight of 12,000, monopalmitic acid ester of TMP / EO adduct having a weight average molecular weight of 8000, monobehenic acid ester of TMP / EO adduct having a weight average molecular weight of 10,000, weight average molecular weight of 12000 And monolaurate of TMP · EO adducts. Preferred is a monostearic acid ester of TMPEO adduct having a weight average molecular weight of 9000 to 10,000.
In the present invention, the weight average molecular weight is a value measured by gel permeation chromatography.

  Another component constituting the dispersant for hydrophobic fiber papermaking of the present invention is an anionic surfactant (B), preferably a fatty acid soap (B1) and a phosphate metal salt (B2) of a higher alcohol. These (B1) and (B2) may be used alone or in combination.

A preferable example of (B1) is a fatty acid soap having 12 to 22 carbon atoms, more preferably a fatty acid soap having 16 to 22 carbon atoms, from the viewpoint of dispersibility and water solubility in water.
Preferable (B2) is a phosphate metal salt of a higher alcohol having 8 to 22 carbon atoms, more preferably a phosphate metal salt of a higher alcohol having 12 to 22 carbon atoms, from the viewpoint of dispersibility and water solubility. . These may be used alone or in combination.

The fatty acid having 12 to 22 carbon atoms of (B1) may be linear or branched, saturated or unsaturated, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, Examples include linolenic acid, ricinoleic acid, and behenic acid. More preferred among these fatty acids are oleic acid, linoleic acid and ricinoleic acid, and particularly preferred are oleic acid and ricinoleic acid.
Examples of the neutralizing metal of the fatty acid soap include alkali metals such as sodium, potassium and lithium; alkaline earth metals such as calcium and magnesium. Preferred are alkali metals, and more preferred are sodium and potassium.

  Specific examples of (B1) include oleic acid sodium salt, oleic acid potassium salt, ricinoleic acid sodium salt, and resinolenic acid potassium salt. Preference is given to potassium oleate and potassium resinoleate.

Further, the higher alcohol having 8 to 22 carbon atoms of (B2) may be linear, branched, saturated or unsaturated, octyl alcohol, 2-ethylhexyl alcohol, decyl alcohol, lauryl alcohol, myristyl alcohol, Examples include cetyl alcohol, isocetyl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, and behenyl alcohol. More preferred are lauryl alcohol, cetyl alcohol, and stearyl alcohol.
Examples of the neutralizing metal for phosphate include alkali metals such as sodium, potassium and lithium; alkaline earth metals such as calcium and magnesium. Preferred are alkali metals, and more preferred are sodium and potassium.

  Specific examples of (B2) include 2-ethylhexyl alcohol phosphate potassium salt, decyl alcohol phosphate potassium salt, lauryl alcohol phosphate potassium salt, myristyl alcohol phosphate potassium salt, cetyl alcohol phosphate potassium salt, stearyl alcohol phosphate potassium salt, behenyl alcohol phosphate potassium Examples include salt. More preferred are lauryl alcohol phosphate potassium salt, cetyl alcohol phosphate potassium salt, and stearyl alcohol phosphate potassium salt.

The mass ratio [(A) / (B)] of (A) and (B) in the paper dispersant of the present invention is usually 40/60 to 90/10, preferably 42/58 to 80/20, More preferably, it is 45 / 55-75 / 25.
When (A) / (B) is 90/10 or less, the appearance stability of the dispersant is good, and when it is 40/60 or more, the dispersibility of the dispersant is good.

In addition to the above (A) and (B), the papermaking dispersant of the present invention contains a nonionic surfactant (C) and other additives (D) to the extent that the effects of the present invention are not impaired. May be.
(C) includes nonionic surfactants other than (A).

Specific examples of (C) include adducts of 3 to 30 moles of higher alcohols (8 to 24 carbon atoms) with ethylene oxide (hereinafter abbreviated as EO), propylene oxides of higher alcohols (8 to 24 carbon atoms) (hereinafter abbreviated as PO). ) 3 to 30 mol / EO 3 to 50 mol adduct, 3 to 6-valent polyhydric alcohol excluding castor oil and hydrogenated castor oil (for example, trimethylolpropane, glycerin, pentaerythrit, sorbitan, sorbit, etc.) and carbon number EO 3-30 mol adducts of esters from 8-22 fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, linolenic acid, ricinoleic acid and behenic acid , And fatty acid (carbon number 8 to 2) such as esters.
In the dispersant of the present invention, the content of (C) is usually 10% by mass or less, preferably 5% by mass or less.

  Examples of other additives (D) include silicone compounds, waxes, antioxidants, ultraviolet absorbers, and fragrances. The content of (D) varies depending on the type and purpose, but is usually 3% by mass or less, preferably 0.1 to 1% by mass based on the mass of the dispersant.

  Although the manufacturing method of the dispersing agent of this invention is not specifically limited, For example, each said component is prepared in the arbitrary order in the mixing tank which has a vertical stirrer, and if necessary, it heats (for example, 40-70 degreeC), and mixes. Can be created.

  Synthetic fibers for papermaking obtained by processing using the papermaking dispersant of the present invention are fibers made of commonly used thermoplastic resins, and examples of resins include polyolefin resins, polyester resins, polyamide resins, and the like. It can be illustrated. Of these, polyolefin-based resins and polyester-based resins are preferably used as raw materials for synthetic fibers for papermaking.

Examples of the polyolefin resin include polyethylene, polypropylene, ethylene / vinyl acetate copolymer, ethylene / propylene copolymer, and ethylene / propylene / 1-butene copolymer.
Examples of the polyester-based resin include polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, polyethylene terephthalate / isophthalate, and polyether polyester.
Examples of the polyamide-based resin include 6,6-nylon and 6-nylon.

The synthetic fiber for papermaking of the present invention is selected from one or more of the above thermoplastic resins and can be obtained by a melt spinning method, as long as the effects of the present invention are not impaired. Ordinarily used additives such as may be blended.
The single yarn fineness of the fiber is preferably 0.1 to 10 dtex, and the fiber length is preferably 0.5 to 25 mm.

  There is no restriction | limiting in particular in the method of providing the dispersing agent of this invention to a fiber, It can provide in arbitrary processes, such as spinning and extending | stretching. For example, it is possible to use a known method such as an oiling roller method, a dipping method, or a spray method using an emulsion of 1 to 20% by mass (a pure component obtained by removing water from an oil agent, hereinafter referred to as a solid component) emulsified with water. it can.

  By these methods, the dispersant of the present invention is preferably applied to the fiber mass in an amount of 0.05 to 2% by mass as a solid content. More preferably, it is 0.2-1.5 mass%. When the applied amount is 0.05% by mass or more, the dispersibility is sufficient, and when it is 2% by mass or less, foaming in the dispersion tank is small.

  The synthetic fiber for papermaking of the present invention is dispersed in water to form a slurry, and papermaking is performed by a commonly used papermaking method such as a round netting method or a slanted short netting method, whereby the nonwoven fabric of the present invention can be obtained. Further, at the time of papermaking, a regenerated fiber such as viscose rayon, a semi-synthetic fiber such as acetate, and a natural fiber such as cotton can be mixed and used as necessary within the range not impairing the effects of the present invention. The amount of these fibers other than the synthetic fiber for papermaking of the present invention is preferably 50% by mass or less, more preferably 20% by mass or less, based on the total fibers.

  Although the use in which the nonwoven fabric of this invention is used is not specifically limited, Filter bags, such as a black tea pack and green tea, a wiping cloth, a wet towel, a wet tissue, a paper diaper, a battery separator plate, etc. are mentioned.

[Example]
EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples and comparative examples, but the present invention is not limited to these examples. Below, a part means a mass part and% means the mass%.
The fatty acid soap and phosphate metal salt used in the blending used hydrated substances, but the number of parts described is a pure conversion excluding moisture. Further, the dispersant used in the examples and comparative examples of the present invention was used after the active ingredient was further adjusted to 50%.

Example 1
Each component of the following prescription was charged into a blending tank having a vertical stirrer and mixed at 40 to 50 ° C. to obtain 100 parts of a paper yellowing dispersant [1] of the present invention in the form of a slightly yellow paste.
Formula:
Monostearic acid ester of TMP · EO adduct having a weight average molecular weight of 6000 (60 parts)
Lisinoleic acid potassium salt (40 parts)

Example 2
Each component of the following formulation was charged into a blending tank having a vertical stirrer and mixed at 40 to 50 ° C. to obtain 100 parts of a paper yellowing dispersant [2] of the present invention in the form of a slightly yellow paste.
Formula:
Monopalmitate of TMP / EO adduct with a weight average molecular weight of 8000 (60 parts)
Oleic acid sodium salt (40 parts)

Example 3
Each component of the following formulation was charged into a blending tank having a vertical stirrer and mixed at 40 to 50 ° C. to obtain 100 parts of a paper yellowing dispersant [3] of the present invention in the form of a slightly yellow paste.
Formula:
Monobehenic acid ester of TMP · EO adduct with a weight average molecular weight of 10,000 (55 parts)
Lisinoleic acid potassium salt (35 parts)
Myristyl alcohol PO3 mol EO5 mol adduct (10 parts)

Example 4
Each component of the following formulation was charged into a blending tank having a vertical stirrer and mixed at 40 to 50 ° C. to obtain 100 parts of a paper paste dispersant [4] of the present invention in the form of a white paste.
Formula:
Monostearic acid ester of TMP · EO adduct having a weight average molecular weight of 12,000 (60 parts)
Stearyl phosphate potassium salt (40 parts)

Example 5
Each component of the following formulation was charged into a blending tank having a vertical stirrer and mixed at 40 to 50 ° C. to obtain 100 parts of a paper paste dispersant [5] of the present invention in the form of a white paste.
Formula:
Monostearic acid ester of TMP · EO adduct having a weight average molecular weight of 10,000 (55 parts)
Cetyl phosphate potassium salt (40 parts)
Lauryl alcohol PO3 mol EO5 mol adduct (5 parts)

Comparative Example 1
Each component of the following formulation was charged into a blending tank having a vertical stirrer and mixed at 40 to 50 ° C. to obtain 100 parts of a paper yellowing dispersant [6] of the present invention in the form of a slightly yellow paste.
Formula:
Monopalmitate of TMP / EO adduct with a weight average molecular weight of 4000 (60 parts)
Oleic acid potassium salt (40 parts)

Comparative Example 2
Each component of the following prescription was charged in a blending tank having a vertical stirrer and mixed at 40 to 50 ° C. to obtain 100 parts of a paper yellowing dispersant [7] of the present invention in the form of a slightly yellow paste.
Formula:
Monolauric acid ester of TMP / EO adduct having a weight average molecular weight of 20,000 (60 parts)
Lisinoleic acid potassium salt (40 parts)

Comparative Example 3
Each component of the following formulation was charged into a blending tank having a vertical stirrer and mixed at 40 to 50 ° C. to obtain 100 parts of a paper yellowing dispersant [8] of the present invention in the form of a slightly yellow paste.
Formula:
Monostearic acid ester of TMP · EO adduct having a weight average molecular weight of 10,000 (20 parts)
Oleic acid sodium salt (80 parts)

Comparative Example 4
Each component of the following formulation was charged into a blending tank having a vertical stirrer and mixed at 40 to 50 ° C. to obtain 100 parts of a paper yellowing dispersant [9] of the present invention in the form of a slightly yellow paste.
Formula:
Monopalmitate of TMP / EO adduct with a weight average molecular weight of 8000 (60 parts)
Octyl alcohol PO14 mol EO13 mol adduct (40 parts)

Comparative Example 5
Each component of the following prescription was charged into a blending tank having a vertical stirrer and mixed at 40 to 50 ° C. to obtain 100 parts of a paper yellowing dispersant [10] of the present invention in the form of a slightly yellow paste.
Formula:
Monostearic acid ester of TMP · EO adduct having a weight average molecular weight of 12,000 (30 parts)
Stearyl alcohol phosphate potassium salt (70 parts)

  Using the papermaking dispersants [1] to [10] obtained in Examples 1 to 5 and Comparative Examples 1 to 5, the fiber dispersion stability, fiber adhesion foam, and foaming property were evaluated. The test methods and evaluation criteria for each test item are as follows.

  Preparation of test emulsion: 2 g of the paste-like dispersant obtained in Examples 1 to 5 and Comparative Examples 1 to 5 was taken into a 500 ml beaker, followed by addition of 498 ml of warm water of 25 to 40 ° C., and a magnetic stirrer. The mixture was stirred for 10 minutes to prepare an emulsion having an oil solid content of 2.0%.

  Fiber for test: Polypropylene (single yarn fineness: 2.2 dtex, fiber length: 5 mm) 35% of the oily agent solid content emulsion prepared above was adhered to the fiber by spray lubrication (oily solid content) A fiber having an adhesion amount of 0.7% was used.

Dispersion stability of fiber: 500 g of ion-exchanged water is collected in a 500 ml beaker, and 1.35 g of test fiber is put therein, and stirred for 1 minute with a magnetic stirrer (rotation speed: 1,000 rpm). The fiber aggregation state 10 minutes after stirring was visually judged according to the following criteria, and used as an index of fiber dispersion stability.
Criteria A: No aggregated fiber is observed.
○: Slightly aggregated fibers are observed.
Δ: Agglomerated fibers are clearly recognized.
X: Remarkably many aggregated fibers.

Fiber wettability: After stopping stirring, the wet state of the fiber and emulsion was visually determined according to the following criteria.
Judgment criteria A: The wet state of the fiber is very good.
○: The wet state of the fiber is good, but there is a portion that is not slightly wet.
(Triangle | delta): A part of fiber does not get wet and floats up from the water surface.
X: The fibers do not get wet at all, and all float above the water surface.

Fiber-attached foam: Immediately after evaluating the dispersion stability of the fiber, the presence or absence of foam attached to the fiber was visually determined according to the following criteria.
Judgment criteria A: There are no attached bubbles.
○: There are bubbles adhering very slightly.
Δ: Some bubbles are attached.
X: There are many bubbles adhering.

  Foaming property: After determining the fiber adhering foam, 20 ml of the residual liquid from which the fiber has been removed is collected in a 100 ml stoppered measuring cylinder, and shaken up and down 30 times (30 times / 15 seconds, shaking width of about 10 cm), The height (mm) of the foam after 1 minute was measured.

The fiber to which the synthetic fiber oil for papermaking of the present invention is adhered has better dispersibility stability in water than those using a conventional oil. Furthermore, since there are few foaming in a papermaking process, it is suitable for the papermaking process in which the quality improvement and speeding-up of a nonwoven fabric are calculated | required. Moreover, it is suitable also for the processing agent of the spunlace nonwoven fabric whose production volume is increasing rapidly in recent years.

Claims (6)

  It consists of a mono-fatty acid ester (A) of an ethylene oxide adduct of trimethylolpropane and an anionic surfactant (B), the weight average molecular weight of (A) is 5000 to 12000, and the mass ratio of (A) and (B) A dispersant for hydrophobic fiber papermaking, wherein [(A) / (B)] is 40/60 to 90/10.   The dispersant for hydrophobic fiber papermaking according to claim 1, wherein (B) is a fatty acid soap (B1) having 12 to 22 carbon atoms and / or a phosphate metal salt (B2) of a higher alcohol having 8 to 22 carbon atoms.   The dispersant for hydrophobic fiber papermaking according to claim 1 or 2, wherein the weight average molecular weight of (A) is 8000 to 11,000.   The hydrophobic fiber papermaking dispersant according to any one of claims 1 to 3, wherein the hydrophobic fiber is a polyolefin fiber or a polyester fiber.   A synthetic fiber for papermaking obtained by attaching 0.05 to 2% by mass of the papermaking dispersant according to any one of claims 1 to 4 to hydrophobic fibers. A nonwoven fabric obtained by papermaking the synthetic fiber according to claim 5.