JP2002265911A - Aqueous emulsion type epoxy adhesive and method for treating wet papermaking fiber web using the same - Google Patents

Abstract

(57) [Summary] (Modified) [Problem] A water-based emulsion-type epoxy adhesive and a wet papermaking fiber which can obtain a cured product of a wet papermaking fiber web having a short curing time and excellent in solvent resistance and non-hygroscopicity. A web processing method is provided. An aqueous emulsion type epoxy adhesive comprising an aqueous emulsion prepared through a first step, a second step and a third step. First step: a step of partially reacting a primary amino group of an aromatic polyamine compound with an epoxy group of a polyvalent epoxy compound to form an epoxy prepolymer Second step: formed by a first step Reacting the epoxy prepolymer with the organic monocarboxylic acid to form an organic carboxylate of the epoxy prepolymer Third step: preparing an aqueous emulsion of the organic carboxylate of the epoxy prepolymer generated in the second step Preparation process

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aqueous emulsion type epoxy adhesive and a method for treating a wet-laid fiber web using the same. An aqueous emulsion-type epoxy-based adhesive is applied to a wet-laid wet fiber web, cured by heating and drying, and used as a reinforcing material for plastic molded products, printed wiring boards, and the like. The present invention relates to an improvement in such a water-based emulsion type epoxy adhesive and a method for treating a wet papermaking fiber web using the same.

[0002]

2. Description of the Related Art Conventionally, as an aqueous emulsion type epoxy adhesive as described above, 1) an aqueous emulsion containing an epoxy resin and a curing agent thereof (Japanese Patent Laid-Open No. 63-505)
99) 2) Aqueous emulsion containing an acid added to a partially reacted product of an epoxy resin and an aliphatic amine (JP-A-6-310823) 3) Necessary for a reaction product of an epoxy resin and an acrylic resin Aqueous emulsions containing a cross-linking agent as required (Japanese Patent Laid-Open No.
3) has been proposed. However, the conventional example 1) has a problem that the curing time is long and the cured product of the wet papermaking fiber web obtained by using the same has high hygroscopicity. Although the curing time is short, there is still a problem that the obtained cured product has a high hygroscopic property. Further, in the above-mentioned conventional example 3), although the obtained cured product has a low hygroscopic property, the solvent resistance of the cured product is low. Is low. If the curing time is long, not only does the productivity of the cured product deteriorate, but also the in-line production of the cured product is not possible.If the hygroscopicity is high or the solvent resistance is low, the application of the cured product is restricted accordingly. If, for example, the hygroscopicity is high, such a cured product cannot be used as an electrical insulating material.

[0003]

An object of the present invention is to provide a water-based emulsion type epoxy system which can obtain a cured product of a wet papermaking fiber web having a short curing time, low hygroscopicity and high solvent resistance. An adhesive and a method for treating a wet-laid fiber web using the same.

[0004]

Means for Solving the Problems The present inventors have studied to solve the above-mentioned problems, and as a result, as an aqueous emulsion type epoxy prepolymer, an organic carboxylic acid of an epoxy prepolymer prepared through a specific process is used. An aqueous emulsion of a salt is correct and suitable, and a method for treating a wet-laid fiber web using an aqueous emulsion-type epoxy adhesive includes a wet-fiber web obtained by wet-forming an aqueous emulsion of an organic carboxylate of such an epoxy prepolymer. It has been found that it is correct and preferable to heat and dry after adhering to a predetermined amount.

That is, the present invention provides the following first step, second step
The present invention relates to an aqueous emulsion type epoxy adhesive comprising an aqueous emulsion prepared through the steps and the third step.

First step: a step of partially reacting a primary amino group of a polyamine compound represented by the following formula 1 or 2 with an epoxy group of a polyepoxy compound to form an epoxy prepolymer. Second step: a step of reacting the epoxy prepolymer produced in the first step with the following organic carboxylic acid to produce an organic carboxylic acid salt of the epoxy prepolymer Third step: an epoxy produced in the second step Preparing an aqueous emulsion of a prepolymer organic carboxylate

[0007]

[Formula 1] (H ₂ N−) _m X ¹

[Formula 2] (H ₂ N—CH ₂ —) _n X ²

In the formulas (1) and (2), X ¹ and X ² : benzene, naphthalene, diphenyl ether, diphenylmethane or diphenylsulfone
two when m and n are 2, and three when m and n are three, residues excluding hydrogen directly bonded to an aromatic ring, m, n: 2 or 3 organic carboxylic acid: formic acid , One or more selected from acetic acid and propionic acid

The present invention also relates to a method in which the above-mentioned aqueous emulsion type epoxy adhesive or a water diluent thereof is applied to a wet-laid wet fiber web as a solid content relative to the dry fiber web in an amount of 5 to 30% by weight. %, And a method for treating a wet papermaking fiber web which is heated and dried after being attached.

First, an aqueous emulsion type epoxy adhesive according to the present invention will be described. The aqueous emulsion type epoxy adhesive according to the present invention comprises an aqueous emulsion prepared through the above first, second and third steps.

In the first step, an epoxy prepolymer is formed by partially reacting a primary amino group of the polyamine compound represented by the above formula 1 or 2 with an epoxy group of the polyepoxy compound. It is. Here, the meaning of partially reacting the primary amino group of the polyvalent amine compound with the epoxy group of the polyvalent epoxy compound means that all of the primary amino groups of the polyvalent amine compound are converted to tertiary amino groups. However, not all of the epoxy groups of the polyepoxy compound are ring-opened, but unreacted primary amino groups and / or partially reacted secondary amino groups are added to the resulting epoxy prepolymer. , Unreacted epoxy groups.

The degree to which the primary amino group of the polyvalent amine compound is partially reacted with the epoxy group of the polyvalent epoxy compound can be appropriately adjusted depending on the reaction conditions, and is not particularly limited. Number of moles of amino group / Number of moles of epoxy group of polyvalent epoxy compound = 0.25 / 1 to 1
/ 1 is preferable, and the molar ratio of the primary amino group of the polyvalent amine compound / the molar number of the epoxy group of the epoxy compound is 0.4 / 1 to 0.6 / 1. Is more preferred. The reaction temperature is preferably set to 40 to 60 ° C. Then, under such conditions, the reaction is preferably stopped when the epoxy groups in the resulting epoxy prepolymer become 10 to 50% of the epoxy groups in the polyvalent epoxy compound used as the raw material.

The polyvalent amine compound to be subjected to the first step includes: 1) o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, naphthalenediamines, 4,4'-diaminodiphenyl ether, 3,4 '
Polyamine compounds represented by the formula 1, such as -diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 1,2,4-benzenetriamine, 2) o-xylylenediamine, m
And polyvalent amine compounds represented by Formula 2 such as -xylylenediamine and p-xylylenediamine. Among them, o-xylylenediamine, m-xylylenediamine, p
-Xylylenediamine is preferred.

The polyepoxy compound used in the first step includes 1) bisphenol A diglycidyl ether, bisphenol A diglycidyl ether oligomer, bisphenol A diβ-methyl glycidyl ether,
Bisphenol A di-β-glycidyl ether oligomer,
Bisphenol F diglycidyl ether, tetrahydroxyphenylmethane tetraglycidyl ether, resorcinol diglycidyl ether, halogenated bisphenol A diglycidyl ether, halogenated bisphenol A diglycidyl ether oligomer, novolak glycidyl ether, novolak glycidyl ether oligomer, cresol novolac glycidyl ether, Cresol novolak glycidyl ether oligomer, polyalkylene glycol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether oligomer, diglycidyl ether of bisphenol A alkylene oxide adduct, glycerin triglycidyl ether, pentaerythritol di Glycidyl ether type epoxy resin such as ricidyl ether; 2) glycidyl ester type epoxy such as p-oxybenzoic acid glycidyl ether ester, phthalic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexatetrahydrophthalic acid diglycidyl ester; Resin, 3) glycidylaniline, tetraglycidyldiaminodiphenylmethane,
Glycidylamine resins such as triglycidyl isocyanurate, 4) epoxidized polybutadiene, epoxidized soybean oil, linear aliphatic epoxy resins such as 3,4-epoxy-6-methylcyclohexylmethyl, and phenol novolak type epoxy resins. Among them, bisphenol A diglycidyl ether, bisphenol A diglycidyl ether oligomer, bisphenol A diβ methyl glycidyl ether, bisphenol A diβ glycidyl ether oligomer, bisphenol F diglycidyl ether, tetrahydroxyphenylmethane tetraglycidyl ether, resorcinol diglycidyl ether, Aromatic glycidyl ether type epoxy resins such as halogenated bisphenol A diglycidyl ether, halogenated bisphenol A diglycidyl ether oligomer, novolak glycidyl ether, novolak glycidyl ether oligomer, cresol novolac glycidyl ether, and cresol novolac glycidyl ether oligomer are preferred. These polyepoxy compounds can be used alone or in a mixture. Among them, bisphenol A diglycidyl ether alone, novolak glycidyl ether alone, cresol novolac glycidyl ether alone, bisphenol A diglycidyl ether and novolak A mixture with glycidyl ether,
Mixtures of bisphenol A diglycidyl ether and cresol novolak glycidyl ether, and mixtures of bisphenol A glycidyl ether, novolak glycidyl ether, and cresol novolak glycidyl ether are preferred.

The second step is a step of reacting the epoxy prepolymer produced in the first step with a specific organic carboxylic acid to produce an organic carboxylic acid salt of the epoxy prepolymer. The organic carboxylic acid used here is one or more selected from formic acid, acetic acid and propionic acid. The amount of the organic carboxylic acid used here is not particularly limited, but may be one of the polyvalent amine compounds used in the first step.
Number of moles of primary amino group / number of moles of organic carboxylic acid = 1 /
The amount is preferably 0.5 to 1 / 1.5, and the number of moles of the primary amino group of the polyvalent amine compound used in the first step / the number of moles of the organic carboxylic acid = 1/0. 7 to 1 /
It is more preferable that the amount be 1.1. The organic carboxylic acid can be used as it is, but can also be used in the form of an aqueous liquid, in which case, 20% by weight
It is preferable to use the above aqueous liquid.

The third step is a step of preparing an aqueous emulsion of the organic carboxylate of the epoxy prepolymer produced in the second step. Here, water is added to the organic carboxylate of the epoxy prepolymer generated in the second step and mixed to prepare an aqueous emulsion as an aqueous emulsion type epoxy adhesive according to the present invention. The amount of water used and the temperature during mixing are not particularly limited, but the amount of water is preferably 100 to 2,000 parts by weight per 100 parts by weight of the organic carboxylate of the epoxy prepolymer. It is preferably set to 0 to 40 ° C. The mixing means is not particularly limited, and includes various known mixing means such as a turbine type, a paddle type, and an anchor type stirrer, as well as a high-pressure jet homogenizer, an ultrasonic homogenizer, and a colloid mill. Can be used.

The water-based emulsion type epoxy adhesive according to the present invention has been described above. In the first step, the primary amino group of the polyvalent amine compound and the epoxy of the polyvalent epoxy compound are added in the presence of an organic solvent. The group can also be partially reacted. The organic solvent used in this case is
An organic solvent having a boiling point of less than 100 ° C or an organic solvent having an azeotropic temperature with water of less than 100 ° C.

The organic solvent having a boiling point of less than 100 ° C. includes: 1) a ketone solvent such as acetone and 2-butanone;
Ether solvents such as diethyl ether, tetrahydrofuran and tetrahydropyran; 3) alcohol solvents such as methanol, ethanol, n-propanol and isopropanol; and 4) aromatic solvents such as benzene. Examples of the organic solvent having an azeotropic temperature with water of less than 100 ° C. include 1) alcohol solvents such as n-butanol, 2-butanol and t-butanol, 2) ether solvents such as dioxane, 3) toluene, xylene and the like. Aromatic solvents. These organic solvents can be used alone or as a mixture. Among them, each of acetone, 2-butanone and tetrahydrofuran alone, acetone / 2-butanone, acetone / tetrahydrofuran, acetone / isopropanol, 2-butanone / tetrahydrofuran, 2-
Mixtures of butanone / isopropanol and tetrahydrofuran / isopropanol are preferred. The amount of these organic solvents used is usually 10 to 200 parts by weight, preferably 20 to 100 parts by weight, per 100 parts by weight of the total of the polyamine compound and the polyepoxy compound. I do.

When an organic solvent is used in the first step, the epoxy prepolymer is reacted with the organic carboxylic acid in the second step in the presence of the organic solvent, and in the third step, the organic solvent of the epoxy prepolymer containing the organic solvent is used. Prepare an aqueous emulsion of the carboxylate. The aqueous emulsion containing the organic solvent thus prepared is also the aqueous emulsion type epoxy adhesive according to the present invention.

The aqueous emulsion containing an organic solvent as described above can also be used as the aqueous emulsion type epoxy adhesive according to the present invention. However, the aqueous emulsion containing such an organic solvent is contained through the following fourth step. The aqueous emulsion from which the organic solvent has been separated is preferably used as the aqueous emulsion type epoxy adhesive according to the present invention. Fourth step: a step of separating the organic solvent from the aqueous emulsion of the organic carboxylate of the epoxy prepolymer containing the organic solvent prepared in the third step to prepare an aqueous emulsion containing substantially no organic solvent.

The separation of the organic solvent in the fourth step can be carried out by a method known per se, but is usually carried out by distilling off the organic solvent under reduced pressure. For example, the organic solvent is distilled off under reduced pressure at a product temperature of 50 ° C. or less, preferably 30 ° C. or less.

Next, a method for treating a wet-type papermaking fiber web according to the present invention will be described. The wet papermaking fiber web treatment method according to the present invention comprises the aqueous emulsion type epoxy adhesive according to the present invention as described above or a water dilution thereof,
This is a method of heating and drying after attaching to a wet fiber web made by wet papermaking.

As a method of adhesion, a usual method such as a spray method, a flow coater method, a saturator method and a padder method can be applied. The concentration of the aqueous emulsion at the time of adhesion is usually 3 to 30% by weight, preferably 5 to 20% by weight. The amount of the aqueous emulsion-type epoxy adhesive according to the present invention is 5 to 30% by weight, preferably 8 to 25% by weight, as a solid content with respect to the dry fiber web.

The wet fiber web to be treated in the method for treating a wet-laid fiber web according to the present invention is not particularly limited. Examples of the wet fiber web include polyparaphenylene terephthalamide fiber and polyparaphenylenediphenyl. A heat-resistant fiber containing one or more selected from ether terephthalamide fiber, polymetaphenylene isophthalamide fiber, wholly aromatic polyester fiber and polyphenol fiber in a dry matter equivalent of 70% by weight or more is preferable.

As described above, the aqueous emulsion type epoxy adhesive according to the present invention or a water diluent thereof is applied to a wet-fiber wet paper web, heated and dried, and if necessary, post-cured. Then, the primary amino group and / or the secondary amino group remaining in the adhesive and the epoxy group react quickly to form a crosslinked polymer, and a hardened product which is strongly adhered in a short time can be obtained. Therefore, such a cured product can be produced in-line, and the cured product has low hygroscopicity and high solvent resistance, and thus is suitable as a reinforcing material for a printed wiring board, for example.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the aqueous emulsion type epoxy adhesive according to the present invention include the following 1) to 3).
Is mentioned. 1) An aqueous emulsion type epoxy adhesive comprising an aqueous emulsion prepared through the following first, second and third steps. First step: bisphenol A diglycidyl ether 76
136 g of m-xylylenediamine was gradually added to 0 g with stirring over 30 minutes, and a primary amino group of the m-xylylenediamine and an epoxy group of the bisphenol A diglycidyl ether were partially reacted to obtain Step of forming an epoxy prepolymer having an unreacted epoxy group corresponding to 27% of the epoxy groups in bisphenol A diglycidyl ether Second step: To the epoxy prepolymer formed in the first step, 73.6 g of formic acid is ionized. A step of slowly adding a formic acid aqueous solution dissolved in 294 g of exchanged water over 1 hour with stirring to form a formate of an epoxy prepolymer Third step: ion exchange with a formate of an epoxy prepolymer generated in the second step Step of preparing aqueous emulsion of formate of epoxy prepolymer by adding 2320 g of water under stirring

2) An aqueous emulsion type epoxy adhesive comprising an aqueous emulsion prepared through the following first, second and third steps. First step: Cresol novolak type epoxy resin 738
was dissolved in 360 g of acetone, and 198 g of 4,4'-diaminodiphenylmethane was gradually added thereto over 30 minutes with stirring, so that the primary amino group of the 4,4'-diaminodiphenylmethane and the cresol novolac epoxy were added. A step of partially reacting with an epoxy group of the resin to form an acetone solution of an epoxy prepolymer having an unreacted epoxy group corresponding to 43% of an epoxy group in the cresol novolac type epoxy resin; 120 g of acetic acid is gradually added to the acetone solution of the epoxy prepolymer produced in one step under stirring over 1 hour to produce an acetone solution of acetate of the epoxy prepolymer. Third step: produced in the second step. 3384 g of ion-exchanged water is added to the acetone solution of the acetate of the epoxy prepolymer with stirring, and the acetone-containing solution is added. Preparing an aqueous emulsion of acetate of a oxy prepolymer

3) An aqueous emulsion type epoxy adhesive comprising an aqueous emulsion prepared through the following first, second, third and fourth steps. First step: bisphenol A diglycidyl ether 76
0 g was dissolved in 600 g of 2-butanone, and 136 g of m-xylylenediamine was gradually added thereto over 30 minutes with stirring to obtain a primary amino group of the m-xylylenediamine and an epoxy of bisphenol A diglycidyl ether. Partially reacting the epoxy group with the group to form a 2-butanone solution of an epoxy prepolymer having an unreacted epoxy group corresponding to 33% of the epoxy group in the bisphenol A diglycidyl ether. 108 g of acetic acid is gradually added to the 2-butanone solution of the epoxy prepolymer produced in the step with stirring over 1 hour to produce a 2-butanone solution of an acetate salt of the epoxy prepolymer Third step: Second step 2700 g of ion-exchanged water was added to the 2-butanone solution of the acetate salt of the epoxy prepolymer produced in the above step under stirring to contain 2-butanone. Step 4: preparing an aqueous emulsion of an acetate of an epoxy prepolymer to be prepared from the aqueous emulsion of an acetate of an epoxy prepolymer containing 2-butanone prepared in the third step under reduced pressure at a product temperature of 30 ° C. A step of distilling a total of 720 g of butanone and water to prepare an aqueous emulsion substantially free of 2-butanone

The method for treating a wet-laid fiber web according to the present invention includes the following 4). 4) The aqueous emulsion type epoxy adhesive according to the present invention of 1) to 3) is diluted with ion-exchanged water to obtain a solid content of 1%.
An aqueous emulsion of 2% by weight was applied to a wet-fiber web of polyparaphenylene terephthalamide wet-processed so as to have a solid content of 28.6% by weight based on the dry fiber web. Heat drying for 1 minute, and post-curing at 150 ° C. for 1 hour.

Hereinafter, the present invention will be described in more detail with reference to examples and the like, but the present invention is not limited to these examples. In the following Examples and Comparative Examples,% means% by weight.

[0031]

[Example] Test Category 1 (Preparation of aqueous emulsion type epoxy adhesive)-Preparation of aqueous emulsion type epoxy adhesive (P-1) As a polyvalent epoxy compound, bisphenol A diglycidyl ether (epoxy equivalent 190, Toto Kasei) 760 g (equivalent to 4 moles as an epoxy group) of a product name (YD-128, manufactured by the company) was charged into a reaction vessel equipped with a stirrer and a thermometer. While maintaining the reaction temperature at 40 to 45 ° C., 136 g of m-xylylenediamine (2 mol as a primary amino group) as a polyvalent amine compound was added over 30 minutes with stirring, and epoxy of bisphenol A diglycidyl ether was added. Group and m-
The amino group of xylylenediamine was partially reacted. During the reaction, the produced epoxy prepolymer was sampled successively, and its oxirane oxygen content was measured. As a result, the oxirane oxygen content was 1.9% (27% of the charged epoxy group remaining amount).
%), The product temperature was cooled to 30 ° C. (first step). Then, 73.6 g of formic acid (1.
(6 mol) in 294 g of ion-exchanged water was added over 1 hour with stirring (second step). Then, 2320 g of ion-exchanged water was added to the reaction vessel with stirring to obtain an aqueous emulsion (third step). When this aqueous emulsion was analyzed, the solid content was 25%, the pH was 6.1, the viscosity at 25 ° C. was 210 mPa · s, and the appearance was milky white. This aqueous emulsion was used as an aqueous emulsion type epoxy adhesive (P-1).

Preparation of aqueous emulsion type epoxy adhesives (P-2) and (R-1) In the same manner as the aqueous emulsion type epoxy adhesive (P-1), the aqueous emulsion type epoxy adhesives (P-1) −
2) and (R-1) were prepared.

Preparation of aqueous emulsion type epoxy adhesive (P-3) 738 g of cresol novolak type epoxy resin (epoxy equivalent: 205, trade name YDCN-702 manufactured by Toto Kasei Co., Ltd.) as a polyvalent epoxy compound (3 as an epoxy group) .6
And 360 g of acetone as an organic solvent were charged into a reaction vessel equipped with a stirrer and a thermometer, mixed and dissolved. While maintaining the reaction temperature at 50 to 55 ° C., 4,4′-diaminodiphenylmethane 1 was used as a polyamine compound.
98 g (2 mol as a primary amino group) was added over 30 minutes with stirring, and the epoxy group of the cresol novolak type epoxy resin was partially reacted with the amino group of 4,4'-diaminodiphenylmethane. During the reaction, the produced epoxy prepolymer was sampled successively, and the oxirane oxygen content was measured. When the oxirane oxygen became 1.9% (corresponding to 43% of the epoxy group remaining amount at the time of preparation), the product was obtained. The temperature was cooled to 30 ° C. (first step). Then, 120 g (2 mol) of acetic acid was added to the reaction vessel with stirring (second step). Then, 3384 g of ion-exchanged water was added to the reaction vessel with stirring over 1 hour to obtain an aqueous emulsion (third step). Analysis of this aqueous emulsion showed a solids content of 20%, a pH of 5.7 and a viscosity at 25 ° C. of 6
5 mPa · s and the appearance was milky white. This aqueous emulsion was used as an aqueous emulsion type epoxy adhesive (P-
3).

Preparation of aqueous emulsion type epoxy adhesive (P-4), (R-2) In the same manner as the aqueous emulsion type epoxy adhesive (P-3), the aqueous emulsion type epoxy adhesive (P-4) −
4) and (R-2) were prepared.

Preparation of aqueous emulsion type epoxy adhesive (P-5) 760 g of bisphenol A diglycidyl ether (epoxy equivalent: 190, trade name: YD-128 manufactured by Toto Kasei Co., Ltd.) as a polyvalent epoxy compound (4 as epoxy group) And 600 g of 2-butanone as an organic solvent were charged into a reaction vessel equipped with a stirrer and a thermometer, mixed and dissolved. While maintaining the reaction temperature at 50 to 55 ° C., 136 g of m-xylylenediamine (2 mol as a primary amino group) as a polyvalent amine compound was added over 30 minutes with stirring, and epoxy of bisphenol A diglycidyl ether was added. The group was partially reacted with the amino group of m-xylylenediamine. During the reaction, the produced epoxy prepolymer was sampled sequentially, and the oxirane oxygen content was measured. When the oxirane oxygen content reached 1.4% (corresponding to 33% of the remaining epoxy group when charged), the product was obtained. The temperature was cooled to 30 ° C. (first step). Next, 108 g of acetic acid was added to the reaction vessel.
(1.8 mol) was added with stirring (second step). Then, 2700 g of ion-exchanged water was added to the reaction vessel with stirring over 1 hour (third step). Further, 2-butanone and water were added under a reduced pressure for a total of 720
g was distilled off to obtain an aqueous emulsion (fourth step). Analysis of this aqueous emulsion showed a solids content of 25.
%, PH is 5.6, viscosity at 25 ° C. is 176 mPa · s,
The appearance was milky white. This aqueous emulsion was used as an aqueous emulsion type epoxy adhesive (P-5).

Preparation of the aqueous emulsion type epoxy adhesive (P-6) The aqueous emulsion type epoxy adhesive (P-6) was prepared in the same manner as the aqueous emulsion type epoxy adhesive (P-5).
6) was prepared. Table 1 summarizes the contents of each aqueous emulsion type epoxy adhesive prepared as described above.

[0037]

[Table 1]

In Table 1, the type of the adhesive: the type of the prepared aqueous emulsion type epoxy-based adhesive The ratio of the organic solvent: the ratio of the amount of the organic solvent to the total weight of the polyvalent amine compound and the polyvalent epoxy compound (% by weight) * 1: Number of moles of primary amino group of polyvalent amine compound / number of moles of epoxy group of polyvalent epoxy compound Residual amount of epoxy group: ratio of epoxy group in epoxy prepolymer to epoxy group in polyvalent epoxy compound ( %) Organic carboxylic acid ratio: mol number of primary amino group of polyvalent amine compound / mol number of organic carboxylic acid A-1: m-xylylenediamine A-2: 4,4'-diaminodiphenylmethane a-1 : Triethylenetetramine E-1: Bisphenol A diglycidyl ether (epoxy equivalent = 190) E-1: Cresol novolak type epoxy Shi resin (average nucleus number = 5, an epoxy equivalent weight = 205) S-1: acetone S-2: 2-butanone S-3: 2-butanone / isopropyl alcohol = 2 /
1 (weight ratio) mixture

Test Category 2 (Production of wet-laid fiber web, its treatment and evaluation)-Production of wet-laid fiber web Washed polyparaphenylene terephthalamide fiber (trade name: Kevlar, 0.17 tex count, manufactured by Toray DuPont) (1.5 denier), a fiber length of 3 mm｝ and polyparaphenylene terephthalamide fiber fibrid (trade name: Tiara manufactured by Daicel Co., Ltd.), a tackifier comprising a copolymer of polyacrylamide and sodium polyacrylate 20pp
m into an aqueous ion-exchange solution (hereinafter referred to as white water) and mix and stir to obtain the polyparaphenylene terephthalamide fiber /
A slurry having a fiber concentration of 0.2% and containing the polyparaphenylene terephthalamide fiber fibrid in a ratio of 70/30 (weight ratio) was prepared. Using an inclined type paper making machine, the prepared slurry was made into paper at a speed of 30 m / min while being diluted and dispersed with white water to a fiber concentration of 0.015%, and then dewatered under reduced pressure and washed while flowing down ion-exchanged water.
A wet fiber web having a water content of 65% and a dry weight of 56 g / m ² was obtained.

Treatment of wet papermaking fiber web Each aqueous emulsion type epoxy adhesive prepared in test category 1 was diluted to 12% with ion-exchanged water, and the diluted liquid was converted to the wet fiber web obtained above in terms of dry matter. 14g / m
² (adhesion amount corresponding to 28.6% as a solid content with respect to the dried fiber web), and then subjected to a surface fluorine-processed Yankee dryer having an infrared auxiliary heating device, and heated and dried at 135 ° C. for 3 minutes. And 70 g of rice tsubo
/ M ² of the band-shaped cured product 1 was obtained. It was further heated at 150 ° C. for 1 hour to obtain a post-cured band-shaped cured product 2 having a rice area of 70 g / m ² .

Evaluation of quick-curing property Each of the band-shaped cured product 1 and the band-shaped cured product 2 was 15 mm in width.
A test piece having a length of 150 mm was cut out and the tensile strength was measured. From the measured row section length, (row section length of band-shaped cured product 1 /
The value calculated from the formula of (cross section length of the band-shaped cured product 2) × 100 was determined based on the following criteria, and the quick curing property was evaluated. The results are summarized in Table 2. Evaluation criteria of fast-curing ability ：: 90 or more ○: 70 or more and less than 90 Δ: 50 or more and less than 70 ×: less than 50

Evaluation of Solvent Resistance A test piece having a width of 15 mm and a length of 150 mm was cut out from the band-shaped cured product 2 and immersed in acetone at 25 ° C. for 1 minute, and the tensile strength was measured without drying the acetone. From the measured line length, (line length of band-shaped cured material 2 after immersion in acetone / line length of band-shaped cured material 2 before acetone immersion) × 100
Was determined according to the following criteria, and the solvent resistance was evaluated. The results are summarized in Table 2. Evaluation criteria for solvent resistance ◎: 75 or more ○: 50 or more and less than 75 Δ: 25 or more and less than 50 ×: less than 25

Evaluation of Non-Hygroscopic Property A test piece having a width of 200 mm and a length of 200 mm was cut out from the band-shaped cured product 2 and left in an atmosphere at 85 ° C. and a relative humidity of 85% for 96 hours, and the moisture absorption was measured. The moisture absorption was determined based on the following criteria, and the non-hygroscopicity was evaluated. The results are summarized in Table 2. Evaluation criteria for hygroscopicity ◎: less than 1.5% ：: 1.5% or more and less than 2.0% △: 2.0% or more and less than 2.5% ×: 2.5% or more

[0044]

[Table 2]

In Table 2, R-3: an aqueous emulsion type epoxy adhesive containing novolak type epoxy resin (trade name: WEX-5002, manufactured by Toto Kasei Co., Ltd.) and triethylenetetramine R-4: aqueous acrylic resin Reaction product with a specific water-soluble epoxy resin (Dec Fine 02 manufactured by Dainippon Ink and Chemicals, Inc.)
70) and an aqueous emulsion type epoxy adhesive containing trimethylolmelamine

[0046]

As is apparent from the above description, the present invention described above has an effect that a cured product of a wet papermaking fiber web having a short curing time and excellent in solvent resistance and non-hygroscopicity can be obtained.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Rikuo Tokaibayashi 2-5 Minatomachi, Gamagori-shi, Aichi Takemoto Oil Company F-term (reference) 4J040 EC031 EC041 EC061 EC071 EC081 EC101 EC121 EC131 EC151 EC241 EC331 HB03 HB08 HB15 HB19 HB24 HC08 KA23 LA00 LA07 LA09 MA10 MB02 MB09 NA20 PA30 QA01 QA04 4L055 AF32 AF33 AF34 AF35 AF44 AG87 AH37 BE10 BE11 FA19 FA30 GA01 GA33 GA50

Claims (9)

[Claims] 1. An aqueous emulsion type epoxy adhesive comprising an aqueous emulsion prepared through the following first, second and third steps. First step: a step of partially reacting a primary amino group of a polyvalent amine compound represented by the following formula 1 or 2 with an epoxy group of a polyvalent epoxy compound to form an epoxy prepolymer second step : A step of reacting the epoxy prepolymer produced in the first step with the following organic carboxylic acid to produce an organic carboxylate of the epoxy prepolymer. Third step: the epoxy prepolymer produced in the second step Step of preparing an aqueous emulsion of an organic carboxylate (Formula 1) (H ₂ N—) _m X ¹ (Formula 2) (H ₂ N—CH ₂ —) _n X ² (X ¹ in Formulas 1 and ² ) , X ² : from benzene, naphthalene, diphenyl ether, diphenylmethane or diphenylsulfone
two residues when m and n are 2, and three residues when m and n are 3, residues m and n excluding hydrogen directly bonded to an aromatic ring:
2 or 3) Organic carboxylic acid: one or more selected from formic acid, acetic acid and propionic acid 2. In the first step, a primary amino group of a polyvalent amine compound and a polyvalent amine are added in the presence of an organic solvent having a boiling point of less than 100 ° C. or an organic solvent having an azeotropic temperature with water of less than 100 ° C. In the second step, an epoxy prepolymer is reacted with an organic carboxylic acid in the presence of an organic solvent in a second step, and in the third step, an epoxy resin containing an organic solvent is reacted. The aqueous emulsion type epoxy adhesive according to claim 1, wherein an aqueous emulsion of a polymer organic carboxylate is prepared. 3. The aqueous emulsion type epoxy adhesive according to claim 2, further comprising an aqueous emulsion prepared through the following fourth step. Fourth step: a step of separating the organic solvent from the aqueous emulsion of the organic carboxylate of the epoxy prepolymer containing the organic solvent prepared in the third step to prepare an aqueous emulsion containing substantially no organic solvent. 4. In the first step, the primary amino group of the polyamine compound and the epoxy group of the polyepoxy compound are
Number of moles of primary amino group of polyamine compound / number of moles of epoxy group of polyvalent epoxy compound = 0.25 / 1 to 1/1
The epoxy prepolymer having an unreacted epoxy group corresponding to 10 to 50% of the epoxy group in the polyvalent epoxy compound is produced by partially reacting the epoxy prepolymer using the following ratio. 4. The aqueous emulsion type epoxy adhesive according to any one of the above items. 5. In the second step, the epoxy prepolymer and the number of moles of the primary amino group of the polyvalent amine compound used in the first step / the number of moles of the organic carboxylic acid = 1 / 0.5 to 1
The aqueous emulsion type epoxy adhesive according to any one of claims 1 to 4, wherein the aqueous emulsion type epoxy adhesive is reacted with an organic carboxylic acid in an amount of /1.5. 6. The aqueous emulsion type epoxy adhesive according to claim 1, wherein the polyvalent amine compound is xylylenediamine. 7. The aqueous emulsion type epoxy adhesive according to claim 1, wherein the polyvalent epoxy compound is an aromatic glycidyl ether type epoxy resin. 8. An aqueous emulsion type epoxy adhesive according to any one of claims 1 to 7, or a water diluent thereof, is added to a wet-laid wet fiber web at a solid content of 5 to 5% based on the dry fiber web. A method for treating a wet papermaking fiber web, wherein the web is heated and dried after being attached so as to be 30% by weight. 9. A wet fiber web selected from the group consisting of polyparaphenylene terephthalamide fiber, polyparaphenylene diphenyl ether terephthalamide fiber, polymetaphenylene isophthalamide fiber, wholly aromatic polyester fiber and polyphenol fiber. 9. The wet papermaking fiber web treatment method according to claim 8, wherein the wet papermaking fiber web contains at least 70% by weight in terms of dry matter.