JP2024006437A - Resin particle dispersion for paper coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a resin particle dispersion for paper coating, capable of obtaining a coated paper having excellent water repellency and oil resistance; a coating liquid for paper, containing the resin particle dispersion; a coated paper using the coating liquid; and a method for producing the coated paper.

SOLUTION: A resin particle dispersion for paper coating comprises a resin particle that contains a polyester-based resin X, wherein: the resin particle contains a modified silicone oil; the polyester-based resin X comprises an amorphous polyester-based resin A that contains an alcohol component containing a divalent or more alcohol and a carboxylic acid component containing one or more selected from aromatic dicarboxylic acid and aliphatic dicarboxylic acid; and the dispersant is water.

SELECTED DRAWING: None

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a resin particle dispersion for coating paper, a paper coating solution containing the resin particle dispersion, and a coated paper using the coating solution.

Conventionally, paper materials that can be used for paper labels, wrapping paper, paper containers, etc. that require water resistance have been laminated with plastic films such as polyethylene or polypropylene to impart water repellency and oil resistance. Paper has been used. However, paper laminated with plastic film is difficult to recycle. Therefore, as environmental awareness has increased in recent years, technologies that provide water repellency and oil resistance in place of lamination have been sought and investigated.

For example, in Patent Document 1, for the purpose of providing a moisture-proof laminate that has high moisture-proof properties and can be recovered as waste paper, at least one side of the paper support has an aspect ratio of 5 or more and an average particle diameter of 5 In a moisture-proof paper with a moisture-proof composition layer made of a flat pigment and a synthetic resin having a thickness of ~50 μm, a crosslinked body of a water-soluble resin of 0.1 to 10 g/m ² is formed on the moisture-proof composition layer. Moisture-proof laminates are described that are provided with a covering layer.
Furthermore, Patent Document 2 discloses that in a silicone paper processing agent containing (A) 100 parts by mass of organopolysiloxane, (E) 100 to 100,000 parts by mass of water, and (F) 0.1 to 100 parts by mass of surfactant, 50 parts by mass of It further contains ~1000 parts by mass of (C) a cellulose resin, in which 0.5 to 2.5 hydroxyl groups per glucose unit are etherified or esterified, and the cellulose resin has a 2% aqueous solution at 20°C. A paper processing agent is described which is characterized by a viscosity of 2 to 100 mPa·s.

JP 9-268494 JP2006-144214

However, with the techniques of Patent Documents 1 and 2, it was not possible to obtain sufficient water repellency as in paper obtained by laminating a plastic film. Moreover, with the techniques of Patent Documents 1 and 2, it was difficult to achieve both water repellency and oil resistance.
The present invention provides a resin particle dispersion for coating paper that can obtain coated paper with excellent water repellency and oil resistance, a paper coating solution containing the resin particle dispersion, and a paper coating solution using the coating solution. Our goal is to provide coated paper.

The present inventors have developed resin particles containing a polyester resin containing a modified silicone and an alcohol component containing a dihydric or higher alcohol, and a carboxylic acid component containing one or more selected from aromatic dicarboxylic acids and aliphatic dicarboxylic acids. It has been found that the above problems can be solved by forming a coating layer on the surface of a paper base material using a resin particle dispersion dispersed in an aqueous medium.

That is, the present invention provides the following [1] to [3].
[1] A paper coating resin particle dispersion containing resin particles containing polyester resin X, wherein the resin particles contain modified silicone oil, and the polyester resin and a carboxylic acid component containing one or more selected from aromatic dicarboxylic acids and aliphatic dicarboxylic acids, the dispersion medium being water, for paper coating. Resin particle dispersion liquid.
[2] A paper coating liquid containing the resin particle dispersion described in [1] above.
[3] Coated paper having a coating layer formed by coating at least one side of a paper base material with the coating liquid described in [2] above.

According to the present invention, there is provided a resin particle dispersion for coating paper that can obtain coated paper with excellent water repellency and oil resistance, a coating liquid for paper containing the resin particle dispersion, and a coating liquid for paper that can obtain coated paper with excellent water repellency and oil resistance. We can provide the coated paper used.

[Resin particle dispersion for paper coating]
The paper coating resin particle dispersion of the present invention (hereinafter also simply referred to as "resin particle dispersion") is a paper coating containing resin particles containing polyester resin X (hereinafter also simply referred to as "resin particles"). This is an industrial resin particle dispersion, which contains an amorphous polyester resin A, and uses water as a dispersion medium.

In the resin particle dispersion of the present invention, deionized water, ion-exchanged water, or distilled water is preferably used as the dispersion medium water.
Moreover, the dispersion medium may further contain an organic solvent. Examples of the organic solvent include aliphatic alcohols having 1 to 4 carbon atoms such as methanol, ethanol, and 2-propanol; ketones having 3 to 8 carbon atoms such as acetone and methyl ethyl ketone; ethers such as diethyl ether and tetrahydrofuran. Examples include water-soluble organic solvents that dissolve in water.
The content of water in the dispersion medium is preferably 60% by mass or more, more preferably 70% by mass or more, still more preferably 90% by mass or more, even more preferably 95% by mass or more, from the viewpoint of environmental friendliness. The content is preferably 100% by mass or less, and even more preferably 100% by mass.

According to the present invention, coated paper with excellent water repellency and oil resistance can be obtained. Although the reason is not certain, it is thought to be as follows.
Silicone is an organosilicon polymer and is known to have high water repellency and oil resistance. However, in general, when silicone oil is simply applied to a paper base material, it quickly penetrates into the paper base material, resulting in a state similar to an oil stain, and it is not possible to obtain water-repellent paper.
On the other hand, polyester resins obtained by polycondensation of alcohol components and carboxylic acid components have highly polar ester bonds in their polymer skeletons, and also have end groups such as hydroxy groups and carboxy groups, making them difficult to use for paper. It is a highly compatible material.
Therefore, in the present invention, by incorporating silicone oil into resin particles containing a polyester resin, it is possible to obtain a resin particle dispersion that can produce a highly hydrophobic surface. In addition, by using a modified silicone oil having a polar group as the silicone oil used in the present invention, interaction between molecules with resin particles containing a polyester resin will work, and the modified silicone oil will efficiently transfer to the resin particles. It has become possible to create a dispersion state suitable for use as a coating liquid. Furthermore, in the resin particles of the present invention, the modified silicone oil is not chemically covalently bonded to the polyester resin forming the resin particles, so the modified silicone oil has a high degree of molecular freedom and is suitable for paper base materials. When applied to form a coating layer, molecules of modified silicone oil can be oriented on the surface of the coating layer, that is, at the interface with air, which is thought to result in both high water repellency and oil resistance. It will be done.

<Modified silicone oil>
In the present invention, the modified silicone oil is contained in the resin particles without being chemically covalently bonded to the polyester resin forming the resin particles described below.
From the viewpoint of achieving both water repellency and oil resistance, the modified silicone oil preferably has one or more selected from amino groups, epoxy groups, ester groups, hydroxy groups, and carboxy groups in the side chain, one end, or both ends. Also, from the viewpoint of further improving water repellency and oil resistance, it is more preferably a modified silicone having one or more types selected from amino groups, epoxy groups, ester groups, and hydroxy groups in the side chain. More preferably, it is a modified silicone having one or more types selected from an amino group, an epoxy group, and an ester group in its side chain, and even more preferably a modified silicone having an amino group in its side chain.
Note that an amino group, an epoxy group, an ester group, a hydroxy group, and a carboxy group are collectively referred to as a "modified group", and a group containing a modified group and other moieties is also referred to as a "modified group-containing group".

[Modified silicone with a modifying group in the side chain]
The modified silicone having a modifying group in its side chain preferably has the following formula (1-1):

[In the formula, R ¹¹ is each independently a hydrocarbon group having 1 to 6 carbon atoms, R ¹² is each independently an alkylene group having 1 to 10 carbon atoms, and a is 1 or 0. and X ¹ is each independently a group containing an amino group, an epoxy group, a hydroxy group, an ester group, or a carboxy group, and * is a bonding site. ] and the following formula (1-2):

[In the formula, R ¹¹ is each independently a hydrocarbon group having 1 or more and 6 or less carbon atoms, and * is a bonding site. ] It has a repeating unit represented by

In addition, the terminal of silicone has the following formula (1-3):

[In the formula, R ¹³ is a hydrocarbon group having 1 or more and 10 or less carbon atoms, and * is a bonding site. ] may be a group represented by.

The number of carbon atoms in the hydrocarbon group of R ¹¹ is 6 or less, preferably 4 or less, more preferably 3 or less, still more preferably 2 or less, and even more preferably 1.
Examples of the hydrocarbon group for R ¹¹ include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group, pentyl group, and phenyl group. Among these, methyl group is preferred.
The number of carbon atoms in the alkylene group of ^R12 is 10 or less, preferably 8 or less, more preferably 5 or less, even more preferably 4 or less, even more preferably 3 or less, even more preferably 2 or less, even more preferably 1. be.
Examples of the alkylene group for R ¹² include methanediyl group, ethane-1,2-diyl group, ethane-1,1-diyl group, n-propane-1,3-diyl group, and n-propane-1,2-diyl group. Diyl group is mentioned. Among these, methanediyl group is preferred.
The number of carbon atoms in the hydrocarbon group of R ¹³ is 10 or less, preferably 8 or less, more preferably 6 or less, even more preferably 4 or less, even more preferably 3 or less, even more preferably 2 or less, even more preferably 1 It is.
Examples of the hydrocarbon group for R ¹³ include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group, pentyl group, and benzyl group.

X ¹ is each independently a group containing an amino group, an epoxy group, a hydroxy group, an ester group, or a carboxy group.
When a is 0, X ¹ may have an ether bond. That is, X ¹ may be an aliphatic hydrocarbon group that may contain an ether bond and is substituted with one or more amino groups, epoxy groups, hydroxy groups, or carboxy groups, and the total number of carbon atoms in X ¹ is , preferably 10 or less, more preferably 9 or less, and preferably 1 or more, more preferably 2 or more.
Note that the aliphatic hydrocarbon group containing an ether bond means that it has an ether bond (-O-) between carbon-carbon bonds.

When the modified silicone is a silicone having an amino group in its side chain, X ¹ is a group containing an amino group. In this case, in the above formula (1-1), a is 1 or 0, X ¹ is each independently -NH ₂ or -R ¹⁴ -NH-R ¹⁴ -NH ₂ , and R ¹⁴ is each Independently, it is preferably an alkylene group having 1 or more and 5 or less carbon atoms; when a is 1, X ¹ is -NH ₂ ; when a is 0, X ¹ is -R ¹⁴ -NH-R ¹⁴ -NH ₂ is more preferable, a is 1, X ¹ is -NH ₂ , and R ¹² is more preferably an alkylene group having 1 or more and 10 or less carbon atoms.
Commercially available modified silicones having amino groups in their side chains include, for example, "KF-868,""KF-865,""KF-864,""X-22-3939A," and "KF-862" (Shin-Etsu Chemical Co., Ltd.). (manufactured by Kogyo Co., Ltd.).

When the modified silicone is a silicone having an epoxy group in its side chain, X ¹ is a group containing an epoxy group. In this case, in the above formula (1-1), a is 1 and X ¹ is an epoxy group, or a is 0 and X ¹ preferably contains an epoxy group and has 1 or more carbon atoms. It is an aliphatic hydrocarbon group that may contain 10 or less ether bonds, more preferably an aliphatic hydrocarbon group that contains an epoxy group and has 1 or more carbon atoms and 6 or less carbon atoms.
Commercially available modified silicones having epoxy groups in their side chains include, for example, "KF-101", "KF-1001", and "X-22-343" (manufactured by Shin-Etsu Chemical Co., Ltd.).

When the modified silicone is a silicone having an ester group in its side chain, X ¹ is a group containing an ester group. In this case, in the above formula (1-1), a is preferably 0 and X ¹ is preferably a group containing an ester group.
A commercially available modified silicone having an ester group in its side chain includes, for example, "X-22-715" (manufactured by Shin-Etsu Chemical Co., Ltd.).

When the modified silicone is a silicone having a hydroxy group in its side chain, X ¹ is a group containing a hydroxy group. In this case, in the above formula (1-1), a is 1, X ¹ is a hydroxy group, or a is 0, and X ¹ is preferably substituted with a hydroxy group and has 1 or more carbon atoms. An aliphatic hydrocarbon group which may contain 10 or less ether bonds, more preferably an aliphatic hydrocarbon group which may contain 1 to 6 carbon atoms and which is substituted with a hydroxy group, and The number of hydroxy groups in ¹ is 1 or more, preferably 5 or less, more preferably 4 or less, even more preferably 2 or less.
Examples of commercially available modified silicones having hydroxyl groups in their side chains include "X-22-4015" and "X-22-4039" (manufactured by Shin-Etsu Chemical Co., Ltd.).

When the modified silicone is a silicone having a carboxy group in its side chain, X ¹ is a group containing a carboxy group.
When a is 1, X ¹ is preferably a carboxy group, and in this case, R ¹² is preferably an alkylene group having 1 to 10 carbon atoms, more preferably an alkylene group having 1 to 5 carbon atoms, and even more preferably is an alkylene group having 1 or more and 3 or less carbon atoms.
When a is 0, X ¹ is preferably an aliphatic hydrocarbon group containing an ether bond and having 1 to 10 carbon atoms substituted with a carboxy group, more preferably an aliphatic hydrocarbon group having 1 to 6 carbon atoms and substituted with a carboxy group. The following aliphatic hydrocarbon groups containing an ether bond may also be used.
A commercially available modified silicone having a carboxyl group in its side chain includes, for example, "X-22-3701E" (manufactured by Shin-Etsu Chemical Co., Ltd.).

[Modified silicone with a modified group at one or both ends]
The modified silicone having a modifying group at one or both ends preferably has the following formula (2-1):

[In the formula, R ²¹ is each independently a hydrocarbon group having 1 to 6 carbon atoms, R ²² is each independently an alkylene group having 1 to 10 carbon atoms, and R ²³ is each independently a hydrocarbon group having 1 to 10 carbon atoms. 10 or less, and each X ² is independently an amino group, an epoxy group, a glycidyl group, a glycidyloxy group, an alicyclic epoxy group, a hydroxy group, a hydroxyalkyloxy group, a carboxy group, or a carboxyalkyloxy group. s is an integer of 1 to 3, t is an integer of 0 to 3, and n is an integer of 5 to 300. ] It is a modified silicone represented by.

The number of carbon atoms in the hydrocarbon group of R ²¹ is 6 or less, preferably 5 or less, more preferably 4 or less, still more preferably 3 or less, even more preferably 2 or less, even more preferably 1.
Examples of the hydrocarbon group for R ²¹ include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group, pentyl group, and phenyl group. Among these, methyl group is preferred.
The number of carbon atoms in the alkylene group of ^R22 is 10 or less, preferably 8 or less, more preferably 5 or less, even more preferably 4 or less, even more preferably 3 or less, and preferably 1 or more, more preferably 2 or more. It is.
Examples of the alkylene group for R ²² include methanediyl group, ethane-1,2-diyl group, ethane-1,1-diyl group, n-propane-1,3-diyl group, and n-propane-1,2-diyl group. Examples include diyl group and 2-methylethane-1,2-diyl group. Among these, ethane-1,2-diyl group, n-propane-1,3-diyl group, and n-propane-1,2-diyl group are preferred, and n-propane-1,2-diyl group is more preferred. .
The number of carbon atoms in the hydrocarbon group of R ²³ is 10 or less, preferably 8 or less, more preferably 6 or less, even more preferably 4 or less, even more preferably 3 or less, even more preferably 2 or less, even more preferably 1 It is.
Examples of the hydrocarbon group for R ²³ include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group, pentyl group, and benzyl group.
X ² is a group containing an amino group, an epoxy group, a hydroxy group, or a carboxy group.
s is 3 or less, preferably 2 or less, and more preferably 1.
t is 3 or less, preferably 2 or less, more preferably 0 or 1.
n is 300 or less, preferably 200 or less, more preferably 100 or less, even more preferably 50 or less, and is 5 or more, preferably 8 or more, more preferably 10 or more.

In a modified silicone having an amino group at one or both ends, X ² is preferably each independently an amino group.
Examples of modified silicones having amino groups at one or both ends include amino-modified silicones at both ends (commercially available products include "X-22-161A,""KF-8012,""KF-8008," and , manufactured by Shin-Etsu Chemical Co., Ltd.)).

In the modified silicone having an epoxy group at one or both ends, X ² is preferably each independently an epoxy group, a glycidyl group, a glycidyloxy group, or an alicyclic epoxy group.
Examples of modified silicones having an epoxy group at one or both ends include epoxy-modified silicones at both ends (commercially available products include "KF-105", "X-22-163A", "X-22-163B"), "X-22-163C", "X-22-169AS", "X-22-169B" (manufactured by Shin-Etsu Chemical Co., Ltd.)), one-end epoxy-modified silicone (commercially available products include "X-22 -173BX" and "X-22-173DX" (manufactured by Shin-Etsu Chemical Co., Ltd.).

In the modified silicone having a hydroxy group at one or both ends, each X ² is independently a hydroxy group or a hydroxyalkyloxy group.
The hydroxyalkyloxy group may have multiple hydroxy groups. The number of carbon atoms in the hydroxyalkyl group is preferably 10 or less, more preferably 8 or less, even more preferably 6 or less.
Examples of modified silicones having a hydroxyl group at one or both ends include carbinol-modified silicones at both ends (commercially available products include "KF-6000,""KF-6001,""KF-6002," and "KF-6000,""KF-6001,""KF-6002,"-6003" (manufactured by Shin-Etsu Chemical Co., Ltd.)), one-end carbinol-modified silicone (commercially available products include, for example, "X-22-170BX", "X-22-170DX", "X-22-176DX") ” and “X-22-176GX-A” (manufactured by Shin-Etsu Chemical Co., Ltd.).

In a modified silicone having a carboxy group at one or both ends, X ² is preferably each independently a carboxy group or a carboxyalkyloxy group.
The carboxyalkyloxy group may have multiple carboxy groups.
Examples of modified silicones having a carboxyl group at one or both ends include carboxy-modified silicones at both ends (commercial product: "X-22-162C" (manufactured by Shin-Etsu Chemical Co., Ltd.)), silicones modified with carboxy at one end. (A commercially available product is "X-22-3710" (manufactured by Shin-Etsu Chemical Co., Ltd.)).

The kinematic viscosity of the modified silicone at 25° C. is preferably 20 mm ² /s or more, more preferably 100 mm ² /s or more, even more preferably 1,000 mm ² /s or more, and preferably 20,000 mm ² /s. Hereinafter, the speed is more preferably 15,000 mm ² /s or less, still more preferably 10,000 mm ² /s or less, even more preferably 5,000 mm ² /s or less, even more preferably 2,000 mm ² /s or less.
The kinematic viscosity of the modified silicone is measured at 25° C. using a fully automatic micro kinematic viscometer (manufactured by Viscotec Co., Ltd.).
The functional group equivalent of the modified silicone is preferably 500 g/mol or more, more preferably 1,000 g/mol or more, even more preferably 2,000 g/mol or more, and preferably 20,000 g/mol or less, more preferably It is 15,000 g/mol or less, more preferably 10,000 g/mol or less. Functional group equivalent means the mass of modified silicone per mole of functional group.

In the resin particle dispersion of the present invention, from the viewpoint of improving water repellency and oil resistance, the content of the modified silicone oil is preferably 1 part by mass or more, and more preferably 1 part by mass or more based on 100 parts by mass of the polyester resin Preferably 5 parts by mass or more, more preferably 10 parts by mass or more, even more preferably 20 parts by mass or more, and preferably 200 parts by mass or less, more preferably 170 parts by mass or less, still more preferably 150 parts by mass or less. It is.

<Polyester resin X>
In the present invention, the polyester-based resin Contains crystalline polyester resin A.
In the present invention, since polyester resin X contains amorphous polyester resin A, excellent water repellency and oil resistance can be imparted to paper when used as a coating liquid for paper.

The crystallinity of a resin is defined as the ratio of the softening point to the maximum peak temperature of endotherm measured by differential scanning calorimeter (DSC), that is, "softening point (°C)/maximum peak temperature of endotherm (°C)". expressed by an index.
"Crystalline resin" refers to a resin having a crystallinity index of 0.6 or more and 1.4 or less.
"Amorphous resin" means that no endothermic peak is observed by differential scanning calorimetry (DSC), or if an endothermic peak is observed, the crystallinity index is less than 0.6 or more than 1.4. Refers to resin.
The maximum endothermic peak temperature refers to the temperature of the peak with the largest peak area among the endothermic peaks observed under the conditions of the measurement method described in the Examples. The crystallinity of the resin can be adjusted by the types and ratios of raw material monomers, manufacturing conditions (for example, reaction temperature, reaction time, cooling rate), and the like.

[Amorphous polyester resin A]
The amorphous polyester resin A includes a polycondensate of an alcohol component containing a dihydric or higher alcohol and a carboxylic acid component containing one or more selected from aromatic dicarboxylic acids and aliphatic dicarboxylic acids. There are no particular limitations, and examples thereof include polyester resins made of polycondensates of alcohol components and carboxylic acid components, and modified products of polyester resins. Examples of modified polyester resins include silicone-modified polyester resins modified with modified silicone, amorphous composite resins containing a polyester resin segment and an addition polymerized resin segment, urethane-modified polyester resins, and epoxy-modified polyester resins. Examples include things.
Among these, the amorphous polyester resin A is preferably one or more selected from polyester resins, silicone-modified polyester resins, and amorphous composite resins, and more preferably silicone-modified polyester resins.

(Alcohol component)
The alcohol component (hereinafter also simply referred to as "alcohol component") constituting the amorphous polyester resin A contains dihydric or higher alcohol.
One kind of alcohol component can be used alone or two or more kinds can be used.
Examples of dihydric or higher alcohols include diols and trihydric or higher polyhydric alcohols.
Examples of diols include aromatic diols and aliphatic diols.
Examples of aromatic diols include alkylene oxide adducts of bisphenol A.
In the present invention, the term "alkylene oxide adduct of bisphenol A" means the entire structure in which alkylene oxide is added to 2,2-bis(4-hydroxyphenyl)propane.
The alkylene oxide adduct of bisphenol A is preferably a compound represented by the following formula (I) from the viewpoint of improving water repellency and oil resistance.

In the above formula (I), OR ¹ and R ² O are both alkyleneoxy groups, and from the viewpoint of improving water repellency and oil resistance, preferably each independently represents an alkyleneoxy group having 1 to 4 carbon atoms. group, more preferably an ethyleneoxy group or a propyleneoxy group, still more preferably a propyleneoxy group.
x and y correspond to the number of moles of alkylene oxide added. Furthermore, from the viewpoint of reactivity with the carboxylic acid component, the average value of the sum of x and y is preferably 2 or more. Further, from the same viewpoint, the average value of the sum of x and y is preferably 7 or less, more preferably 5 or less, and still more preferably 3 or less.
The x number of OR ¹ and the y number of R ² O may be the same or different, but they are preferably the same from the viewpoint of improving the adhesion of the coating layer to paper. The alkylene oxide adducts of bisphenol A may be used alone or in combination of two or more.
From the viewpoint of improving water repellency and oil resistance, the alkylene oxide adduct of bisphenol A is preferably at least one selected from propylene oxide adducts of bisphenol A and ethylene oxide adducts of bisphenol A, more preferably propylene of bisphenol A. It is an oxide adduct.

Examples of the aliphatic diol include linear or branched aliphatic diols having 2 to 20 carbon atoms and alicyclic aliphatic diols.
Examples of linear or branched aliphatic diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 2,3-butanediol. Diol, 1,4-butanediol, 1,2-pentanediol, 1,4-pentanediol, 2,4-pentanediol, 1,2-hexanediol, 1,5-hexanediol, 2,5-hexanediol , 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 1,14-tetradecanediol, 1,16-hexadecanediol, Examples include 3,3-dimethyl-1,2-butanediol. The aliphatic diol is preferably 1,2-propanediol from the viewpoint of improving water repellency and oil resistance.
Examples of the alicyclic aliphatic diol include cyclohexanediol and hydrogenated bisphenol A.
Examples of trihydric or higher polyhydric alcohols include glycerin, pentaerythritol, trimethylolpropane, sorbitol, sorbitan, and the like.

Among these, the alcohol component constituting the amorphous polyester resin A preferably contains either an aromatic diol or an aliphatic diol, and more preferably contains bisphenol A, from the viewpoint of improving water repellency and oil resistance. It contains either an alkylene oxide adduct or 1,2-propanediol, more preferably an alkylene oxide adduct of bisphenol A.
The content of aromatic diol or aliphatic diol in the alcohol component constituting the amorphous polyester resin A is preferably 60 mol% or more, more preferably 80 mol%, from the viewpoint of improving water repellency and oil resistance. Above, it is more preferably 90 mol% or more, even more preferably 95 mol% or more, and preferably 100 mol% or less.

(carboxylic acid component)
The carboxylic acid component (hereinafter also simply referred to as "carboxylic acid component") constituting the amorphous polyester resin A includes one or more selected from aromatic dicarboxylic acids and aliphatic dicarboxylic acids.
The term "carboxylic acid component" includes not only carboxylic acids but also their anhydrides, their alkyl esters having 1 to 3 carbon atoms, and the like. That is, in this specification, when only the name of a carboxylic acid is described, the anhydride, alkyl ester having 1 or more and 3 or less carbon atoms, etc. of the carboxylic acid are also described.

The carboxylic acid component may be used alone or in combination of two or more.
Examples of aromatic dicarboxylic acids include phthalic acid, isophthalic acid, and terephthalic acid. Among these, from the viewpoint of improving water repellency and oil resistance, the aromatic dicarboxylic acids are preferably isophthalic acid and terephthalic acid, and more preferably terephthalic acid.
Examples of the aliphatic dicarboxylic acids include straight chains such as fumaric acid, adipic acid, sebacic acid, maleic acid, azelaic acid, succinic acid, succinic acid substituted with a hydrocarbon group having 1 to 20 carbon atoms, and cyclohexanedicarboxylic acid; Branched or alicyclic aliphatic dicarboxylic acids may be mentioned. Specific examples of succinic acid substituted with a hydrocarbon group having 1 to 20 carbon atoms include dodecylsuccinic acid, dodecenylsuccinic acid, octenylsuccinic acid, and the like. Among these, the aliphatic dicarboxylic acid is preferably one or more selected from fumaric acid, adipic acid, and succinic acid from the viewpoint of improving water repellency and oil resistance.

From the viewpoint of improving water repellency and oil resistance, the total content of aromatic dicarboxylic acids and aliphatic dicarboxylic acids in the carboxylic acid component constituting the amorphous polyester resin A is preferably 60 mol% or more, more preferably is 65 mol% or more, more preferably 70 mol% or more, and preferably 100 mol% or less.

From the viewpoint of improving water repellency and oil resistance, the carboxylic acid component constituting the amorphous polyester resin A preferably contains a trivalent or higher polyvalent carboxylic acid, and more preferably a trivalent or higher aromatic polyvalent carboxylic acid. Contains carboxylic acid.
Examples of the trivalent or higher aromatic polycarboxylic acid include trimellitic acid, 2,5,7-naphthalenetricarboxylic acid, and pyromellitic acid. Among these, trimellitic acid is preferred.
When the carboxylic acid component constituting the amorphous polyester resin A contains a polyvalent carboxylic acid having a valence of 3 or more, the aromatic polyvalent carboxylic acid having a valence of 3 or more in the carboxylic acid component constituting the amorphous polyester resin A From the viewpoint of improving water repellency and oil resistance, the acid content is preferably 3 mol% or more, more preferably 5 mol% or more, even more preferably 10 mol% or more, and preferably 50 mol% or less. , more preferably 40 mol% or less, still more preferably 30 mol% or less.

The equivalent ratio (COOH group/OH group) of the carboxy group (COOH group) of the carboxylic acid component to the hydroxy group (OH group) of the alcohol component constituting the amorphous polyester resin A is preferably 0.7 or more. , and preferably 1.2 or less.

(Component derived from modified silicone)
When the amorphous polyester resin A is a silicone-modified polyester resin, the silicone-modified polyester resin contains, in addition to the above-mentioned alcohol component and carboxylic acid component, from the viewpoint of improving water repellency and oil resistance. Preferably, it contains constituent components. By including the component derived from modified silicone, the modified silicone oil is more easily encapsulated in the resin particles containing the amorphous polyester resin X, and furthermore, it is easier to form a dispersion state suitable for a coating liquid. Therefore, it is easier to improve water repellency and oil resistance.
Examples of constituents derived from modified silicones include modified silicones having a modifying group in the side chain and modified silicones having modifying groups at one or both ends, as exemplified by the above-mentioned modified silicone oil. Among these, from the viewpoint of improving water repellency and oil resistance, the modified silicone-derived component contained in the amorphous polyester resin A is preferably a modified silicone having a modifying group in its side chain, and more preferably Preferably, it is a modified silicone having an amino group in its side chain.

The content of the modified silicone-derived constituents in the amorphous polyester resin A is determined by the total amount of the alcohol component and carboxylic acid component that constitute the amorphous polyester resin A, from the viewpoint of improving water repellency and oil resistance. Based on 100 parts by mass, the amount is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, even more preferably 1.5 parts by mass or more, and preferably 10 parts by mass or less, more preferably 8 parts by mass. part or less, more preferably 6 parts by mass or less.
Note that the above amount is calculated based on the alcohol component, the carboxylic acid component, and the constituent components derived from modified silicone, and does not take into account the amount of dehydration due to condensation.
In addition, when a component derived from modified silicone has a hydroxy group or a carboxy group, it can also be understood as an alcohol component or a carboxylic acid component, but when a compound having a hydroxy group or a carboxy group contains a silicone skeleton, it is considered as a modified silicone component. The component is derived from silicone. For example, when calculating the total amount of the alcohol component and the carboxylic acid component, the component derived from modified silicone having a hydroxy group or a carboxy group is not included in the total amount.

(Raw material monomer for addition polymerization resin segment)
When the amorphous polyester resin A is an amorphous composite resin, the amorphous composite resin contains a polycondensate of the above-mentioned alcohol component and carboxylic acid component as a polyester resin segment, and further contains styrene as an addition polymerized resin segment. It is preferable to include an addition polymer of a raw material monomer containing a system compound.
Examples of the styrene compound include unsubstituted or substituted styrene. Examples of the substituent substituted on styrene include an alkyl group having 1 to 5 carbon atoms, a halogen atom, an alkoxy group having 1 to 5 carbon atoms, a sulfonic acid group, or a salt thereof.
Examples of the styrenic compound include styrene, methylstyrene, α-methylstyrene, β-methylstyrene, tert-butylstyrene, chlorostyrene, chloromethylstyrene, methoxystyrene, styrenesulfonic acid, or a salt thereof. Among these, styrene is preferred.
The content of the styrene compound in the raw material monomer of the addition polymerized resin segment is preferably 50% by mass or more, more preferably 65% by mass or more, even more preferably 75% by mass or more, and preferably 100% by mass or less. , more preferably 95% by mass or less, still more preferably 90% by mass or less, even more preferably 85% by mass or less.

Examples of raw material monomers other than styrene compounds include (meth)acrylic acid esters such as alkyl (meth)acrylates, benzyl (meth)acrylates, and dimethylaminoethyl (meth)acrylate; ethylene, propylene, butadiene, etc. Olefins; halobinyls such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; vinyl ethers such as methyl vinyl ether; vinylidene halides such as vinylidene chloride; N-vinyl compounds such as N-vinylpyrrolidone. . Among these, preferred are (meth)acrylic esters, and more preferred are alkyl (meth)acrylates.

The number of carbon atoms in the alkyl group in the alkyl (meth)acrylate is preferably 1 or more, more preferably 4 or more, even more preferably 6 or more, and preferably 24 or less, more preferably 22 or less, even more preferably 20 It is as follows.
Examples of the alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, (iso)propyl (meth)acrylate, (iso- or tertiary)butyl (meth)acrylate, and (meth)acrylate. ) (iso)amyl acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (iso)octyl (meth)acrylate, (iso)decyl (meth)acrylate, (meth)acrylic acid Examples include (iso)dodecyl, (iso)palmityl (meth)acrylate, (iso)stearyl (meth)acrylate, and (iso)behenyl (meth)acrylate. Among these, preferred is 2-ethylhexyl (meth)acrylate or stearyl (meth)acrylate, more preferred is 2-ethylhexyl (meth)acrylate, and still more preferred is 2-ethylhexyl (meth)acrylate.
Note that "(iso or tertiary)" and "(iso)" mean both the presence and absence of these prefixes, and the absence of these prefixes indicates normal. Moreover, "(meth)acrylic acid" indicates acrylic acid or methacrylic acid.
The content of alkyl (meth)acrylate in the raw material monomer of the addition polymerized resin segment is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and preferably 50% by mass or more. It is at most 35% by mass, more preferably at most 35% by mass, even more preferably at most 25% by mass.

The total content of the styrene compound and (meth)acrylic acid ester in the raw material monomer of the addition polymerized resin segment is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more. The content is preferably 100% by mass or less, and even more preferably 100% by mass.

(Structural unit derived from bireactive monomer)
When the amorphous polyester resin A is an amorphous composite resin, the amorphous polyester resin A is preferably derived from a bireactive monomer bonded to the polyester resin segment and the addition polymerized resin segment via a covalent bond. It is preferable to have a structural unit.
The term "constituent unit derived from a bireactive monomer" means a unit in which a functional group or an addition polymerizable group of a bireactive monomer has reacted.
Examples of the addition polymerizable group include a carbon-carbon unsaturated bond (ethylenic unsaturated bond).
Examples of bireactive monomers include addition-polymerizable monomers having at least one functional group selected from a hydroxyl group, a carboxy group, an epoxy group, a primary amino group, and a secondary amino group in the molecule. . Among these, from the viewpoint of reactivity, the bireactive monomer is preferably an addition-polymerizable monomer having at least one functional group selected from a hydroxyl group and a carboxy group, and more preferably an addition-polymerizable monomer having a carboxy group. It is a monomer.
Examples of the addition polymerizable monomer having a carboxyl group include acrylic acid, methacrylic acid, fumaric acid, and maleic acid. Among these, from the viewpoint of reactivity in both polycondensation reactions and addition polymerization reactions, one or more selected from acrylic acid and methacrylic acid is preferred, and acrylic acid is more preferred.
When the bireactive monomer is an addition polymerizable monomer having a carboxyl group, the amount of the structural unit derived from the bireactive monomer is as follows: Preferably 1 molar part or more, more preferably 3 molar parts or more, still more preferably 5 molar parts or more, and preferably 30 molar parts or less, more preferably 20 molar parts or less, still more preferably 15 molar parts or less, Even more preferably, it is 10 parts by mole or less.

When the amorphous polyester resin A is an amorphous composite resin, the content of the polyester resin segment in the amorphous composite resin is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably The content is 70% by mass or more, and preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 85% by mass or less.
When the amorphous polyester resin A is an amorphous composite resin, the content of addition polymerized resin segments in the amorphous composite resin is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably is 15% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less, even more preferably 30% by mass or less.
When the amorphous polyester resin A is an amorphous composite resin, the content of structural units derived from bireactive monomers in the amorphous composite resin is preferably 0.1% by mass or more, more preferably 0. .3% by mass or more, more preferably 0.5% by mass or more, and preferably 10% by mass or less, more preferably 5% by mass or less, still more preferably 2% by mass or less.
When the amorphous polyester resin A is an amorphous composite resin, the total content of polyester resin segments, addition polymerized resin segments, and structural units derived from bireactive monomers in the amorphous composite resin is preferably is 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, and is preferably 100% by mass or less, even more preferably 100% by mass.
The above amounts are calculated based on the ratio of the amounts of raw material monomers, bireactive monomers, and radical polymerization initiators in the polyester resin segment and addition polymerization resin segment, and exclude the amount of dehydration due to polycondensation in the polyester resin segment, etc. Based on the weight. In addition, when a radical polymerization initiator is used, the mass of the radical polymerization initiator is calculated by including it in the addition polymerization resin segment.

The amorphous polyester resin A can be obtained, for example, by polycondensing an alcohol component, a carboxylic acid component, and, if necessary, a component derived from modified silicone. For example, by polycondensing an alcohol component, a carboxylic acid component, and a component derived from modified silicone in an inert gas atmosphere at a temperature of 150°C or more and 250°C or less, using an esterification catalyst as necessary. can be manufactured.
Examples of the esterification catalyst include tin compounds such as tin (II) di(2-ethylhexanoate) and dibutyltin oxide; titanium compounds such as titanium diisopropylate bistriethanolaminate; and the like. Furthermore, if necessary, an esterification promoter such as 3,4,5-trihydroxybenzoic acid (gallic acid); a radical polymerization inhibitor such as 4-tert-butylcatechol may be used.

In addition, when the amorphous polyester resin A is an amorphous composite resin, for example, step A of polycondensing an alcohol component and a carboxylic acid component, and addition polymerization of a raw material monomer and a bireactive monomer of an addition polymerization resin segment. It may be manufactured by a method including Step B of
Process B may be performed after process A, process A may be performed after process B, or process A and process B may be performed simultaneously.
In Step A, a part of the carboxylic acid component is subjected to a polycondensation reaction, and then after carrying out Step B, the remainder of the carboxylic acid component is added to the polymerization system to complete the polycondensation reaction of Step A and the bireactive monomer or both. A method in which a polycondensation reaction with a carboxy group contained in a component derived from a reactive monomer is further advanced is preferred.

In step A, for example, the alcohol component and the carboxylic acid component are heated at 150° C. or higher at 250° C. in an inert gas atmosphere using the above-mentioned esterification catalyst, esterification promoter, and radical polymerization inhibitor as necessary. Preferably, it is produced by polycondensation at a temperature of .degree. C. or lower.
Examples of the radical polymerization initiator for addition polymerization in step B include peroxides such as dibutyl peroxide, persulfates such as sodium persulfate, and 2,2'-azobis(2,4-dimethylvaleronitrile). Examples include azo compounds.
The amount of the radical polymerization initiator used is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the raw material monomer of the addition polymerization resin segment.
The temperature of addition polymerization is preferably 110°C or higher, more preferably 130°C or higher, and preferably 230°C or lower, more preferably 220°C or lower, even more preferably 210°C or lower.

The softening point of the amorphous polyester resin A is preferably 80°C or higher, more preferably 90°C or higher, and even more preferably 100°C or higher, from the viewpoint of improving water repellency and oil resistance, and from the same point of view. , preferably 170°C or lower, more preferably 150°C or lower, and still more preferably 130°C or lower.
The softening point is measured by the method described in Examples.

The glass transition temperature of the amorphous polyester resin A is preferably 40°C or higher, more preferably 45°C or higher, and even more preferably 50°C or higher, from the viewpoint of improving water repellency and oil resistance. The temperature is 80°C or lower, more preferably 70°C or lower, even more preferably 65°C or lower.
The glass transition temperature is measured using a differential scanning calorimeter, and specifically, by the method described in Examples.

The acid value of the amorphous polyester resin A is preferably 5 mgKOH/g or more, more preferably 10 mgKOH, from the viewpoint of improving the dispersion stability of resin particles in an aqueous medium and improving water repellency and oil resistance. /g or more, more preferably 15 mgKOH/g or more, and preferably 40 mgKOH/g or less, more preferably 37 mgKOH/g or less, still more preferably 35 mgKOH/g or less.
The acid value is measured by the method described in Examples.

From the viewpoint of improving water repellency and oil resistance, the number average molecular weight of the amorphous polyester A is preferably 1,000 or more, more preferably 1,500 or more, still more preferably 2,000 or more, and is 10,000 or less, more preferably 8,000 or less, even more preferably 5,000 or less.
In addition, the weight average molecular weight of the amorphous polyester A is preferably 5,000 or more, more preferably 10,000 or more, and even more preferably 20,000 or more, from the viewpoint of improving water repellency and oil resistance. , preferably 50,000 or less, more preferably 40,000 or less, still more preferably 35,000 or less.

The amorphous polyester resin A may be used alone or in combination of two or more.
The softening point, glass transition temperature, acid value, number average molecular weight, and weight average molecular weight of the amorphous polyester resin A depend on the type of raw material monomer and the amount used, and manufacturing conditions such as reaction temperature, reaction time, and cooling rate. They can be adjusted as appropriate, and their values are determined by the method described in Examples.
In addition, when using a combination of two or more types of amorphous polyester resin A, the values of the softening point, glass transition temperature, acid value, number average molecular weight, and weight average molecular weight obtained as the mixture are respectively as described above. It is preferably within the range.

The polyester resin X may contain resins other than the amorphous polyester resin A.
Examples of other resins include polyester resins other than amorphous polyester resin A, acrylic resins such as styrene-acrylic copolymers, and polyurethane resins.
Examples of polyester resins other than amorphous polyester resin A include polyester resins made of polycondensates of alcohol components and carboxylic acid components as exemplified in the above-mentioned amorphous polyester resin A, and urethane-modified polyester resins. and epoxy-modified polyester resins.

From the viewpoint of improving water repellency and oil resistance, the content of amorphous polyester resin A in the total amount of polyester resin It is at least 75% by mass, even more preferably at least 85% by mass, even more preferably at least 95% by mass, and preferably at most 100% by mass.

In the present invention, the polyester resin X is preferably substantially water-insoluble from the viewpoint of improving water repellency and oil resistance. When the polyester resin can.
Here, "substantially water-insoluble" means that when polyester resin It means that the amount is 1g or less. When the polyester resin X contains acid groups, the amount dissolved is the amount dissolved when the acid groups of the polyester resin X are neutralized by 100 mol % with sodium hydroxide.

In the present invention, when the polyester resin X contains an acid group, the polyester resin X is preferably a neutralized product with a basic compound from the viewpoint of improving the dispersion stability of resin particles in an aqueous medium. .
Examples of the basic compound include metal basic compounds and non-metal basic compounds.
Examples of the metal basic compound include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide.
Examples of the nonmetallic basic compound include ammonia and organic amine compounds.
The organic amine compound contains at least one primary amino group, secondary amino group, or tertiary amino group. The organic amine compound may contain functional groups other than these amino groups. Examples of the functional group include a hydroxy group.
Examples of organic amine compounds include primary, secondary or tertiary aliphatic amines, amino alcohols having at least one amino group and at least one hydroxy group, and specifically, Examples include trimethylamine, ethylamine, diethylamine, triethylamine, and triethanolamine.
The basic compounds can be used alone or in combination of two or more.
Among these, the basic compound is preferably one or more selected from metal basic compounds and non-metal basic compounds.

The equivalent amount of the basic compound used is preferably 50 mol% or more, more preferably 55 mol% or more, still more preferably 60 mol% or more, and preferably 100 mol% or less.
The equivalent amount of the basic compound used can be determined by the following calculation formula (1). When the equivalent amount of the basic compound used is 100 mol% or less, it has the same meaning as the degree of neutralization, and when the equivalent amount of the basic compound used exceeds 100 mol% in the following formula, the basic compound is This means that it is in excess with respect to the acid groups, and the degree of neutralization of the polyester resin X at this time is considered to be 100 mol%.
Equivalent amount of basic compound used (mol%) = {[added mass of basic compound (g)/equivalent amount of basic compound (g/mol)]/[[acid value of polyester resin X (mgKOH/g)× Mass of polyester resin X (g)]/(56.1×1000 (mgKOH/mol))}×100 (1)

Furthermore, the resin particles according to the present invention may contain resins other than polyester resin X, such as styrene-acrylic copolymer, epoxy resin, polycarbonate, polyurethane, etc., to the extent that the effects of the present invention are not impaired. Good too.
Further, the resin particles according to the present invention may contain reinforcing fillers such as fibrous substances, additives such as antioxidants, etc. as optional components within a range that does not impair the effects of the present invention.
From the viewpoint of improving water repellency and oil resistance, the content of polyester resin X in the resin particles according to the present invention is preferably 20% by mass or more, more preferably 30% by mass or more, and still more preferably 35% by mass or more. , even more preferably 40% by mass or more, and preferably less than 100% by mass, more preferably 99% by mass or less, even more preferably 95% by mass or less, even more preferably 90% by mass or less, even more preferably Better is 85% by mass or less.

From the viewpoint of improving water repellency and oil resistance, the content of modified silicone oil in the resin particles according to the present invention is preferably 0.1% by mass or more, more preferably 1% by mass or more, and even more preferably 5% by mass. Above, it is even more preferably 10% by mass or more, and preferably 80% by mass or less, more preferably 70% by mass or less, still more preferably 65% by mass or less, even more preferably 60% by mass or less.

(Manufacture of resin particle dispersion)
The resin particle dispersion of the present invention is preferably produced by a method of dispersing a resin containing polyester resin X and modified silicone oil in an aqueous medium.
The resin particle dispersion can be obtained by adding a resin containing polyester resin X and modified silicone oil to an aqueous medium and performing a dispersion treatment using a dispersion machine, Examples include a method of gradually adding an aqueous medium to a solution to perform phase inversion emulsification. Among these, a method of phase inversion emulsification is preferred from the viewpoint of improving water repellency and oil resistance.

In phase inversion emulsification, first, a resin containing polyester resin X and modified silicone oil are dissolved in an organic solvent to obtain a solution of resin containing polyester resin X and modified silicone oil, and then an aqueous medium is added to the solution. A preferred method is to carry out phase inversion by using a method, followed by removal of the organic solvent.
Examples of organic solvents for dissolving the resin containing polyester resin Solvents include ester solvents such as ethyl acetate and isopropyl acetate; halogenated alkyl solvents such as dichloromethane and chloroform. Among these, from the viewpoint of dissolving the resin containing the polyester resin is methyl ethyl ketone.

When the resin containing polyester resin X contains multiple types of polyester resins X or resins other than polyester resin X, the multiple types of polyester resins Alternatively, the polyester resin You may get it.
The mass ratio [organic solvent/resin] of the organic solvent and the resin containing the polyester resin From this point of view, it is preferably 30/100 or more, more preferably 50/100 or more, even more preferably 70/100 or more, and preferably 500/100 or less, more preferably 400/100 or less, even more preferably 300/100 or more. It is 100 or less, more preferably 250/100 or less.
When the polyester resin X is a neutralized product with a basic compound, after obtaining a solution of the resin containing the polyester resin . Examples of the basic compound include sodium hydroxide and ammonia.
The operation of dissolving the resin containing the polyester resin X in an organic solvent and the subsequent addition of the aqueous solution of the basic compound are usually performed at a temperature below the boiling point of the organic solvent.

From the viewpoint of improving the dispersion stability of the resin particle dispersion, the temperature at which the aqueous medium is added to the solution of the resin containing polyester resin , more preferably 25°C or higher, and preferably 80°C or lower, more preferably 75°C or lower.
From the viewpoint of improving the dispersion stability of the resin particle dispersion, the addition rate of the aqueous medium is preferably 0.5 parts by mass per 100 parts by mass of the resin component constituting the resin particles until the phase inversion is completed. /min, more preferably 1 part by weight or more, even more preferably 3 parts by weight or more, and preferably 100 parts by weight or less, more preferably 50 parts by weight or less, even more preferably It is 30 parts by mass/min or less. There is no limit to the rate of addition of the aqueous medium after phase inversion and after the resin particles have been obtained.
From the viewpoint of improving the productivity of the resin particle dispersion, the amount of the aqueous medium added is preferably 50 parts by mass or more, more preferably 100 parts by mass or more, and The amount is preferably 200 parts by mass or more, and preferably 900 parts by mass or less, more preferably 800 parts by mass or less, and even more preferably 700 parts by mass or less.

After the phase inversion emulsification, it is preferable to remove the organic solvent from the dispersion obtained by the phase inversion emulsification from the viewpoint of improving the dispersion stability of the resin particle dispersion.
Removal of the organic solvent is not particularly limited, and any method can be used.
The obtained resin particle dispersion is preferably filtered through a wire mesh or the like to remove coarse particles and the like. Further, when the organic solvent is removed, water is also reduced by azeotropy together with the organic solvent, so it is preferable to add water to adjust the solid content concentration.

The solid content concentration of the resin particle dispersion of the present invention is preferably 5% by mass or more, more preferably 10% by mass or more, and still more preferably 20% by mass or more, from the viewpoint of improving water repellency and oil resistance. , preferably 50% by mass or less, more preferably 45% by mass or less, still more preferably 40% by mass or less. The solid content concentration of the resin particle dispersion is measured by the method described in Examples.

The pH at 25°C of the resin particle dispersion of the present invention is preferably 6.5 or more, more preferably 7.0 or more, and preferably 9.0 or less, from the viewpoint of improving water repellency and oil resistance. , more preferably 8.5 or less. pH can be measured by the method described in Examples.

The surface tension at 20°C of the resin particle dispersion of the present invention is preferably 50 mN/m or more, more preferably 55 mN/m or more, and preferably 70 mN/m or less, more preferably 65 mN/m or less. . Surface tension can be measured by the method described in Examples.

The resin particle dispersion of the present invention may contain an organic solvent, a humectant, a wetting agent, a penetrating agent, a viscosity modifier, an antifoaming agent, a preservative, an antifungal agent, a rust preventive agent, a pH adjuster, an oxidizing agent, and an antifoaming agent. Various additives such as inhibitors, ultraviolet absorbers, and surfactants may be added.
In addition, surfactants have a very high affinity with water, so their presence in the resin particle dispersion prevents them from being included in the coating layer formed when coating on paper. This results in a decrease in water repellency. Therefore, from the viewpoint of improving water repellency and oil resistance, the resin particle dispersion of the present invention preferably does not substantially contain a surfactant.
Here, "substantially not containing" means that no surfactant is intentionally added, and does not exclude the presence of a small amount of surfactant as an impurity.
In addition, in the present invention, when producing the resin particle dispersion, a method of adding the resin containing the polyester resin X to an aqueous medium and performing a dispersion treatment using a dispersion machine, By using a phase inversion emulsification method in which an aqueous medium is gradually added to a solution, resin particles can be dispersed in an aqueous medium without using a surfactant, resulting in a resin that does not substantially contain a surfactant. A particle dispersion can be obtained.

[Coating liquid]
The resin particle dispersion of the present invention can be used as it is as a coating liquid, but it can also be used by adding and mixing various additives used in coating liquids to the resin particle dispersion as necessary. . That is, the coating liquid of the present invention preferably contains the resin particle dispersion.
As mentioned above, surfactants have a very high affinity with water, so the presence of surfactants in the coating liquid causes the coating layer formed when it is applied to the paper base material to be mixed with water. The coating solution of the present invention preferably does not substantially contain a surfactant, from the viewpoint of improving water repellency, since this results in a decrease in water repellency.

[Method for manufacturing coated paper]
From the viewpoint of improving water repellency and oil resistance, the method for producing coated paper of the present invention preferably includes step 1 of applying the coating liquid to at least one side of a paper base material.
Thereby, coated paper having a coating layer formed by coating at least one side of the paper base material with the coating liquid can be obtained.
The paper base material includes non-coated paper such as high-quality paper, medium-quality paper, and coated paper; coated paper such as art paper, coated paper, and matte coated paper; information paper such as PPC paper; and packaging such as craft paper. Examples include paper; base paper for cardboard; paperboard such as paperboard for folding cartons;
The basis weight of the paper base material is not particularly limited, but from the viewpoint of ease of handling the coated paper and ease of coating on the paper base material, it is preferably 10 g/m ² or more, and preferably 200 g/m ² or less, more preferably 150 g/m ² or less, even more preferably 120 g/m ² or less.

From the viewpoint of improving water repellency and oil resistance, the coating amount of the coating liquid in step 1 is preferably 1 g/m ² or more, more preferably 3 g/m ² or more, and even more preferably 5 g/m 2 in terms of solid content. ² or more, and preferably 30 g/m ² or less, more preferably 25 g/m ² or less, still more preferably 20 g/m ² or less, even more preferably 15 g/m ² or less.
The method of applying the coating liquid to the paper base material in step 1 is not particularly limited, and examples include a roll coater, gravure coater, die coater, curtain coater, spray coater, blade coater, wire bar coater, bar coater, and rod bar. Examples include methods using a coater, an impregnation coater, a cast coater, an air knife coater, a reverse coater, a lip coater, a kiss coater, and the like.

In the present invention, from the viewpoint of improving water repellency and oil resistance, it is preferable to further include a step 2 of drying the coating liquid coated on the paper base material in step 1.
Examples of the drying method in step 2 include stationary drying, blow drying, heat drying, vacuum drying, and infrared drying. The drying method may be used alone or in combination of two or more. Among these, from the viewpoint of operational simplicity, at least one method selected from blow drying and heat drying is preferred, and heat drying is more preferred.
The heating drying method includes a method of heating the surface of the coating liquid on the paper base material by applying hot air, a method of heating the surface of the coating liquid on the paper base material by bringing a heater close to it, and a method of heating the surface of the coating liquid on the paper base material. Examples include a method of heating the surface by bringing a heater into contact with the surface opposite to the surface coated with the coating liquid, and a method of heating by steam curing using high-temperature steam at normal pressure or high pressure.
From the viewpoint of improving water repellency and oil resistance, the drying temperature is preferably 30°C or higher, more preferably 40°C or higher, even more preferably 50°C or higher, even more preferably 70°C or higher, even more preferably 90°C or higher. From the viewpoint of suppressing deformation of the paper base material due to heat and reducing energy, the temperature is preferably 200°C or lower, more preferably 150°C or lower, and still more preferably 110°C or lower.
The drying time is preferably 3 minutes or more, more preferably 5 minutes or more from the viewpoint of improving water repellency and oil resistance, and preferably 30 minutes or more from the viewpoint of suppressing deformation of the paper base material due to heat and reducing energy. It is less than 1 minute, more preferably less than 15 minutes.

[Coated paper]
The coated paper of the present invention preferably has a coating layer formed by coating at least one side of a paper base material with the above-mentioned coating liquid. Since the above-mentioned coating liquid contains the above-mentioned resin particle dispersion, the coating layer of the coated paper of the present invention has excellent water repellency and oil resistance.
The coated paper of the present invention can be produced, for example, by the method for producing coated paper described above.

In the Examples below, various physical properties were measured by the following methods.

[Softening point of resin]
Using a flow tester "CFT-500D" (manufactured by Shimadzu Corporation), 1 g of sample was heated at a heating rate of 6°C/min while applying a load of 1.96 MPa with a plunger to a diameter of 1 mm and a length of 1 mm. was extruded from the nozzle. The fall of the plunger of the flow tester was plotted against the temperature, and the temperature at which half of the sample flowed out was defined as the softening point.

[Glass transition temperature of resin]
Using a differential scanning calorimeter "Q-100" (manufactured by T.A. Instruments Japan Co., Ltd.), 0.01 to 0.02 g of the sample was weighed into an aluminum pan, heated to 200°C, and then The sample was cooled down to 0°C at a cooling rate of 10°C/min to prepare a sample for measurement. Thereafter, the temperature was increased at a rate of 10° C./min, and the amount of heat was measured. Among the observed endothermic peaks, the peak temperature with the largest peak area was defined as the maximum endothermic peak temperature. The temperature at the intersection of the extension line of the baseline below the maximum endothermic peak temperature and the tangent line showing the maximum slope from the rising part of the peak to the apex of the peak was defined as the glass transition temperature.

[Crystallinity index]
Using a differential scanning calorimeter "Q-100" (manufactured by T.A. Instruments Japan Co., Ltd.), 0.01 to 0.02 g of the sample was weighed into an aluminum pan, and the temperature was lowered to zero at a cooling rate of 10°C/min. Cooled to ℃. Next, the sample was allowed to stand still for 1 minute, and then the temperature was raised to 180°C at a heating rate of 10°C/min, and the amount of heat was measured. Among the observed endothermic peaks, the temperature of the peak with the largest peak area was taken as the maximum endothermic peak temperature, and the crystallinity index was calculated according to the following formula.
(Crystallinity index) = Softening point (℃) / Maximum endothermic peak temperature (℃)
[Acid value of resin]
It was measured according to the neutralization titration method described in JIS K0070:1992. However, in this method, the measurement solvent was changed from a mixed solvent of ethanol and ether to a mixed solvent of acetone and toluene [acetone:toluene=1:1 (volume ratio)].

[Number average molecular weight and weight average molecular weight of amorphous polyester resin]
(1) Preparation of sample solution A polyester resin was dissolved in tetrahydrofuran so that the concentration was 0.5 g/100 mL. Next, this solution was filtered using a fluororesin filter "FP-200" (manufactured by Sumitomo Electric Industries, Ltd.) with a pore size of 2 μm to remove insoluble components, and a sample solution was obtained.
(2) Molecular weight measurement Tetrahydrofuran was flowed as an eluent at a flow rate of 1 mL/min, and the column was stabilized in a constant temperature bath at 40°C. 100 μL of the sample solution was injected thereto for measurement. The number average molecular weight and weight average molecular weight of the sample were calculated based on a calibration curve prepared in advance. The calibration curve is based on several types of monodisperse polystyrene [monodisperse polystyrene manufactured by Tosoh Corporation; 2.63×10 ³ , 2.06×10 ⁴ , 1.02×10 ⁵ (weight average molecular weight (Mw)), GL Sciences Monodispersed polystyrene manufactured by Co., Ltd.; 2.10×10 ³ , 7.00×10 ³ , 5.04×10 ⁴ (weight average molecular weight (Mw))] was used as a standard sample.
Measuring device: “CO-8010” (manufactured by Tosoh Corporation)
Analysis column: “GMHXL” + “G3000HXL” (manufactured by Tosoh Corporation)

[Solid content concentration of resin particle dispersion]
Using an infrared moisture meter "FD-230" (manufactured by Kett Science Institute Co., Ltd.), 5 g of a measurement sample was dried at a temperature of 150°C and a measurement mode of 96 (monitoring time 2.5 minutes/fluctuation range 0.05%). The water content (mass %) of the dispersion was measured.
The solid content concentration was calculated according to the following formula.
Solid content concentration (mass%) = 100 - water (mass%)

[Volume average particle diameter (Dv) of resin particles]
The volume average particle diameter Dv was measured using the following measuring device and measurement conditions.
Measuring device: Zeta potential/particle size measuring system “ELSZ-2” (manufactured by Otsuka Electronics Co., Ltd.)
Measurement conditions: cumulant analysis method. A dispersion diluted with water so that the concentration of the particles to be measured is approximately 5 x 10 ^-3 mass % is placed in a measurement cell, the temperature is 25°C, and the number of accumulations is 100. The refractive index (1.333) was input.

[Surface tension of resin particle dispersion]
A platinum plate was immersed in a cylindrical polyethylene container (diameter 3.6 cm x depth 1.2 cm) containing 5 g of sample adjusted to 20°C, and a surface tension meter (Kyowa Interface Science Co., Ltd., "CBVP-Z") was used. The static surface tension at 20° C. was measured using the Wilhelmy method.

[pH of resin particle dispersion]
The pH at 25° C. was measured using a desktop pH meter “F-71” (manufactured by Horiba, Ltd.) using a pH electrode “6337-10D” (manufactured by Horiba, Ltd.).

Production Example A1 (Production of amorphous polyester resin A-1)
The inside of a four-neck flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was replaced with nitrogen, and 4828 g of propylene oxide (2.2) adduct of bisphenol A, 1374 g of terephthalic acid, and di(2-ethyl 35 g of tin(II) hexanoate and 3.5 g of gallic acid were added, and the temperature was raised to 235°C over 1 hour while stirring under a nitrogen atmosphere. After holding at 235°C for 5 hours, the pressure inside the flask was further increased. The pressure was lowered and maintained at 8.3 kPa, and the reaction was carried out for 1 hour. Thereafter, the pressure was returned to atmospheric pressure, and after cooling to 180°C, 480 g of fumaric acid, 318 g of trimellitic anhydride, and 3.5 g of 4-tert-butylcatechol were added, and the temperature was raised stepwise by 10°C every hour to 210°C. . After holding at 210°C for 2 hours, the pressure inside the flask was further lowered and held at 8.3 kPa, and the reaction was carried out until the softening point reached the temperature shown in Table 1, yielding amorphous polyester A-1. . Table 1 shows various physical properties of the resin.

Production Example A2 (Production of amorphous polyester resin A-2)
The inside of a four-necked flask equipped with a nitrogen introduction pipe, a dehydration pipe, a stirrer, a rectification column into which 95°C hot water was introduced, and a thermocouple was replaced with nitrogen, and 2290 g of 1,2-propanediol, 4501 g of terephthalic acid, 35 g of tin(II) di(2-ethylhexanoate) was added, and the temperature was raised stepwise from 180° C. to 230° C. by 10° C. every 2 hours while stirring under a nitrogen atmosphere. After maintaining the temperature at 230° C. for 2 hours, the pressure inside the flask was further lowered and maintained at 8.3 kPa to conduct a reaction for 1 hour. Thereafter, the pressure was returned to atmospheric pressure and after cooling to 180°C, the rectification column was removed, 210 g of fumaric acid and 3.5 g of 4-tert-butylcatechol were added, and the temperature was raised to 210°C in steps of 10°C every hour. After holding at 210°C for 2 hours, the pressure inside the flask was further lowered and held at 8.3 kPa, and the reaction was carried out until the softening point reached the temperature shown in Table 1, yielding amorphous polyester A-2. . Table 1 shows various physical properties of the resin.

Production Example A3 (Production of amorphous polyester resin A-3)
In a four-necked flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple, 3128 g of propylene oxide (2.2) adduct of bisphenol A, 726 g of ethylene oxide (2.2) adduct of bisphenol A, and terephthal were added. 1539 g of acid and 158 g of succinic acid were added, and the temperature was raised to 160° C. while stirring in a nitrogen atmosphere. Thereafter, the reaction was carried out while maintaining the temperature at 160° C. and adding dropwise a mixture of 976 g of styrene, 214 g of 2-ethylhexyl acrylate, and 119 g of di-tert-butyl peroxide. Thereafter, 28 g of tin(II) di(2-ethylhexanoate) and 2.8 g of gallic acid were added, the temperature was raised to 235°C over 8 hours, and the temperature was maintained at 235°C for 10 hours. The pressure was lowered and the reaction was carried out at 8.3 kPa until the softening point shown in Table 1 was reached, yielding amorphous polyester A-3. Table 1 shows various physical properties of the resin.

Production example A4 (manufacture of amorphous polyester resin A-4)
The interior of a four-neck flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was replaced with nitrogen, and 4819 g of propylene oxide (2.2) adduct of bisphenol A, 686 g of terephthalic acid, and modified silicone "KF-"864" (amino-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd., viscosity (25°C): 1700 mm ² /s, functional group equivalent: 3800 g/mol) 198 g, tin (II) di(2-ethylhexanoate) 13.6 g and 1.36 g of gallic acid were added, and the temperature was raised stepwise from 185°C to 235°C by 10°C per hour. Thereafter, the temperature was maintained at 235° C. for 3 hours, and the pressure inside the flask was further lowered and maintained at 8.3 kPa for 1 hour. Thereafter, the pressure was returned to atmospheric pressure, and after cooling to 180°C, 704 g of adipic acid and 582 g of trimellitic anhydride were added, and the temperature was raised to 210°C in steps of 10°C per hour. After holding at 210° C. for 1 hour, the pressure inside the flask was further lowered and the reaction was carried out at 8.3 kPa until the softening point shown in Table 1 was reached, yielding amorphous polyester A-4. Table 1 shows various physical properties of the resin.

<Example 1>
In a four-necked flask equipped with a reflux condenser, a stirrer ("Three-One Motor BL300" (manufactured by Shinto Kagaku Co., Ltd.)), and a thermocouple, 100 g of amorphous polyester resin A-1 was added as a polyester resin. As a modified silicone, 1 g of modified silicone oil O-1 was added and mixed with 200 g of methyl ethyl ketone (MEK) at 30° C. to dissolve the resin. Next, 9.1 g of 5N aqueous sodium hydroxide solution was added and stirred for 60 minutes.
Next, while stirring at 30° C., 600 g of ion-exchanged water was added dropwise at a rate of 20 mL/min to effect phase inversion emulsification. Thereafter, the temperature was raised to 65° C., and while the pressure was gradually reduced from 80 kPa to 30 kPa, methyl ethyl ketone was distilled off, and a portion of the water was further distilled off. After cooling to room temperature, it was filtered through a 150-mesh wire mesh, and the solid content concentration was adjusted to 30% by mass with ion-exchanged water to obtain the resin particle dispersion of Example 1. Table 2 shows the properties of the resin particle dispersion obtained.

<Examples 2 to 12 and Comparative Example 1>
Example 1 was carried out in the same manner as in Example 1, except that the types and amounts of the polyester resin and modified silicone oil were changed to those shown in Table 2, and the amounts of the sodium hydroxide aqueous solution or ammonia aqueous solution were changed to the amounts shown in Table 2. , Examples 2 to 12 and Comparative Example 1 were obtained. Note that in Comparative Example 1, no modified silicone oil was blended. Table 2 shows the properties of the resin particle dispersion obtained.

The modified silicone oils used in the Examples and Comparative Examples shown in Table 2 are as follows. All modified silicone oils are manufactured by Shin-Etsu Chemical Co., Ltd.
・O-1: “KF-864”, amino-modified silicone (viscosity (25°C): 1700 mm ² /s, functional group equivalent: 3800 g/mol)
・O-2: “KF-865”, amino-modified silicone (viscosity (25°C): 110 mm ² /s, functional group equivalent: 5000 g/mol)
・O-3: "X-22-343", epoxy modified silicone (viscosity (25°C): 25 mm ² /s, functional group equivalent: 525 g/mol)
・O-4: "X-22-715", ester-modified silicone (viscosity (25°C): 14000 mm ² /s)
・O-5: “X-22-4015”, hydroxy group-modified silicone (viscosity (25°C): 1700 mm ² /s, hydroxyl value: 30 mgKOH/g)

<Preparation of coated paper>
(Step 1)
The resin particle dispersions obtained in Examples 1 to 12 and Comparative Example 1 were used as coating liquids on PPC paper "J Paper" (basis weight 82 g/m ² , manufactured by Fujifilm Business Innovation Co., Ltd.) as a paper base material. Each was coated using a bar coater (No. 12).
In addition, coating was carried out so that the coating amount was 8 g/m ² as solid content.
(Step 2)
Next, the resin particle dispersion obtained in Examples 1 to 12 and Comparative Example 1 was used on the paper base by drying the resin particle dispersion on the paper base for 5 minutes in a dryer at 80°C. A coated paper having a coating layer consisting of: The water repellency and oil resistance of each of the obtained coated papers were evaluated by the following methods.

[Evaluation of water repellency]
Water repellency was evaluated using JAPAN TAPPI Paper Pulp Test Method No. 68:2000. At room temperature, drop a drop of ion-exchanged water onto the coating layer of the coated paper from 10 mm above the coated paper tilted at 45 degrees, and check what happens after the water droplet passes over the coating layer. By doing so, the following water repellency R0 to R10 was determined. If the water repellency is R6 or higher, the water repellency is excellent. The results are shown in Table 2.
[Water repellency]
R0: A continuous trace with a uniform width R2: A continuous trace with a width slightly narrower than a water drop R4: A continuous trace but broken in places and clearly narrower than a water drop Width indication R6: Half of the trace is wet R7: 1/4 of the trace is wet with elongated water droplets R8: More than 1/4 of the trace is wet with spherical droplets R9: Small spherical water droplets scattered here and there R10: Completely rolling down

[Evaluation of oil resistance]
The above-mentioned coated paper was placed on a horizontal table, and oil droplets of salad oil were dropped onto the coated layer of the coated paper from 10 mm above, and allowed to stand at room temperature for 1 minute. Thereafter, the oil droplets on the sample were wiped off, the state of the surface of the coated paper after wiping was checked, and the oil resistance was evaluated using the following criteria. If the oil resistance is determined to be L3 or higher, the oil resistance is excellent. The results are shown in Table 2.
[Oil resistance criteria]
L5: No oil stains can be seen on the paper L4: Slight oil stains can be seen L3: Oil stains can be seen, but they are smaller than the oil droplets L2: A stain the same size as the oil droplets can be seen L1: From the oil droplets Large stains can be seen

Table 2 shows that the resin particle dispersions of Examples 1 to 12 can provide coated paper with superior water repellency and oil resistance compared to the resin particle dispersion of Comparative Example 1.

According to the present invention, coated paper having a coating layer with excellent water and oil repellency can be obtained, and the amount of resin used can be reduced compared to paper laminated with a plastic film. Therefore, coated paper with high environmental friendliness can be obtained and can be used for paper labels, wrapping paper, paper containers, etc. that require water resistance.

Claims (8)

A paper coating resin particle dispersion containing resin particles containing polyester resin X,
the resin particles contain modified silicone oil,
The polyester resin death,
A resin particle dispersion for paper coating, in which the dispersion medium is water. The paper according to claim 1, wherein the modified silicone oil is a modified silicone having one or more selected from amino groups, epoxy groups, ester groups, hydroxy groups, and carboxy groups in a side chain, one end, or both ends. Resin particle dispersion for coating. The resin particle dispersion for coating paper according to claim 1 or 2, wherein the modified silicone oil has a kinematic viscosity at 25°C of 20 mm ² /s or more and 15,000 mm ² /s or less. The paper coating resin according to any one of claims 1 to 3, wherein the content of the modified silicone oil is 1 part by mass or more and 200 parts by mass or less based on 100 parts by mass of the polyester resin X in the resin particles. Particle dispersion. The resin particle dispersion for coating paper according to any one of claims 1 to 4, wherein the amorphous polyester resin A has a glass transition temperature of 40°C or more and 80°C or less. The resin particle dispersion for coating paper according to any one of claims 1 to 5, which has a surface tension at 20° C. of 50 mN/m or more and 65 mN/m or less. A paper coating liquid containing the resin particle dispersion according to any one of claims 1 to 6. A coated paper comprising a coating layer formed by coating the coating liquid according to claim 7 on at least one side of a paper base material.