WO2021075388A1

WO2021075388A1 - Thermosetting resin composition, coating material for printing, cured product, laminate, and method for producing laminate

Info

Publication number: WO2021075388A1
Application number: PCT/JP2020/038382
Authority: WO
Inventors: 有人市原; 義人廣田
Original assignee: 三井化学株式会社
Priority date: 2019-10-16
Filing date: 2020-10-09
Publication date: 2021-04-22
Also published as: TW202130743A; JPWO2021075388A1; JP7247362B2

Abstract

This thermosetting resin composition contains (A) an alkyl etherified amino resin having a solubility parameter δ (SP value) of at most 10.0, (B) a radical polymer having a hydroxyl group, and (C) an acid catalyst.

Description

Method for manufacturing thermosetting resin composition, coating material for printing, cured product, laminate, and laminate

The present invention relates to a thermosetting resin composition, a coating material for printing, a cured product, a laminate, and a method for producing a laminate.

OPP (biaxially stretched polypropylene film) used as a base material for stickers and labels has low surface free energy, for example, the contact angle of water is 100 ° or more, so the printability of ink is inferior. Therefore, normally, the printability of the ink is improved by forming an easy print layer on the OPP, but this easy print layer does not have sufficient scratch resistance, and the easy print layer is scratched when handled. There was a problem that the design was easily impaired.

Further, Patent Document 1 describes a melamine resin (A) and a fat having 12 to 24 carbon atoms as a peeling coating agent capable of forming a cured film having excellent coating appearance and excellent peeling performance and solvent resistance. A thermosetting release coating agent containing a self-condensate of a group hydroxycarboxylic acid (B) and an acid catalyst (C) is disclosed, and the coating agent may further contain a polyol (D) such as a polyolefin polyol. Has been done.

Further, Patent Document 2 discloses a coating liquid containing a hexamethylol melamine initial polymer as a coating liquid for forming an easy-to-print layer (see Examples of Patent Document 2). Then, in Cited Document 2, after applying the coating liquid to the surface of the resin base material, the coating liquid is heat-treated to form a melamine resin layer, and then an image is printed on the melamine resin layer using a water-based ink. There is.

Japanese Unexamined Patent Publication No. 2019-94483 JP-A-2019-64238

However, Patent Document 1 does not include an example in which a melamine resin and a polyolefin polyol are combined, and there is no description regarding a special effect of combining the melamine resin and the polyolefin polyol. Further, when the present inventors tested using the methylated melamine resin used in the examples of Patent Document 1 and an olefin polymer, the obtained cured film had low transparency and could not be used practically. There was found.

Further, in Patent Document 2, a melamine resin layer is formed as an easy printing layer on the surface of the resin base material, but the adhesion of the melamine resin layer to the resin base material is insufficient.

An object of the present invention is to provide a thermosetting resin composition capable of forming a cured film having excellent adhesion, a coating material for printing, a cured product, a laminate, and a method for producing the laminate.

As a result of diligent studies by the present inventors, a thermosetting resin composition containing an alkyl etherified amino resin having a solubility parameter δ (SP value) of 10.0 or less, a radical polymer having a hydroxyl group, and an acid catalyst. It has been found that the above-mentioned problems can be solved by using a thing.

That is, the present invention includes the following aspects.

The present invention [1] comprises (A) an alkyl etherified amino resin having a solubility parameter δ (SP value) of 10.0 or less, (B) a radical polymer having a hydroxyl group, and (C) an acid catalyst. Contains the thermosetting resin composition to be contained.

The present invention [2] includes the thermosetting resin composition according to the above [1], wherein the mass ratio of the alkyl etherified amino resin to the radical polymer is in the range of 50/50 to 99/1. ..

The present invention [3] includes the thermosetting resin composition according to the above [1], wherein the mass ratio of the alkyl etherified amino resin to the radical polymer is in the range of 1/99 to 49/51. ..

The present invention [4] includes the thermosetting resin composition according to any one of the above [1] to [3], wherein the alkyl etherified amino resin is a butyl etherified melamine resin.

The present invention [5] includes the thermosetting resin composition according to any one of the above [1] to [4], wherein the radical polymer has a hydroxyl value of 20 to 200 mgKOH / g.

In the present invention [6], the thermosetting according to any one of the above [1] to [5], wherein the solubility parameter δ (SP value) of the radical polymer is 8.0 to 9.0. Contains a sex resin composition.

In the present invention [7], the radical polymer is a reaction product of a radical polymer having no hydroxyl group and a monomer having a hydroxyl group, and the radical polymer having no hydroxyl group has 2 to 20 carbon atoms. The above [1], which is at least one polymer selected from the group consisting of a polymer of an olefin, a polymer of an olefin having a plurality of double bonds, and a polymer of an olefin and another radically polymerizable monomer. The thermocurable resin composition according to any one of [6] is included.

The present invention [8] includes the thermosetting resin composition according to any one of the above [1] to [7], wherein the acid catalyst is paratoluenesulfonic acid.

The present invention [9] further contains (D) a fluorine-containing surface conditioner in an amount of 0.1 to 30 parts by mass with respect to 100 parts by mass of the total of the alkyl etherified amino resin and the radical polymer. The thermosetting resin composition according to any one of the above [1] to [8] is included.

The present invention [10] includes a coating material for printing, which comprises the thermosetting resin composition according to any one of the above [1] to [9].

The present invention [11] includes a cured product comprising the thermosetting resin composition according to any one of the above [1] to [9].

The present invention [12] includes the cured product according to the above [11], wherein the contact angle of water is 20 to 89 °.

The present invention [13] is a laminate in which a base material, a cured film, and a printed layer are laminated in this order, and the cured film includes a laminate containing the cured product according to the above [11].

The present invention [14] includes the laminate according to the above [13], wherein the base material is an olefin polymer.

The present invention [15] includes the laminate according to the above [13] or [14], and the base material contains a label including an adhesive region and a non-adhesive region.

In the present invention [16], 60 to 160 of the thermosetting resin composition is applied after the step of applying the thermosetting resin composition according to any one of the above [1] to [9] to the substrate. Includes a method for producing a laminate, which comprises a step of heating to ° C. and curing to form a cured film.

Since the thermosetting resin composition of the present invention contains an alkyl etherified amino resin having an SP value of 10.0 or less, a radical polymer having a hydroxyl group, and an acid catalyst, a cured film having excellent adhesion can be obtained. Can be formed.

Since the coating material for printing of the present invention contains the above-mentioned thermosetting resin composition, it is possible to form a cured film having excellent adhesion.

Since the cured product of the present invention is composed of the above-mentioned thermosetting resin composition, it has excellent adhesion.

Since the laminate of the present invention includes a cured film containing the above-mentioned cured product, it is possible to improve the adhesion of the cured film to the substrate.

Since the label of the present invention includes the above-mentioned laminate and the base material includes an adhesive region and a non-adhesive region, the label can be attached to an object while improving the adhesion of the cured film to the base material. Can be done.

The method for producing a laminated body of the present invention can smoothly produce the above-mentioned laminated body.

FIG. 1 is a side sectional view of a commercial label as an embodiment of the label of the present invention. FIG. 2A is a bottom view of an embodiment of the commercial label shown in FIG. 1 (a mode in which the adhesive region is located at the center). FIG. 2B is a bottom view of another embodiment of the commercial label shown in FIG. 1 (a mode in which the adhesive region is located at the end).

The thermosetting resin composition of the present invention (hereinafter, also simply referred to as “the composition of the present invention”) comprises (A) an alkyl etherified amino resin having a solubility parameter δ (SP value) of 10.0 or less. It contains (B) a radical polymer having a hydroxyl group and (C) an acid catalyst. Details of each component are shown below.

<Alkyl etherified amino resin (A)>
The alkyl etherified amino resin (A) used in the present invention (hereinafter, also simply referred to as “amino resin (A)”) is an alkyl etherified amino resin having a solubility parameter δ (SP value) of 10.0 or less. is there. In the alkyl etherified amino resin, at least a part of the methylol groups of the amino resin (the amino resin refers to a thermosetting resin obtained from an amino compound and formaldehyde) is alkyl etherified (for example, methyl ether). Amino resin that has been converted, ethyl etherified, propyl etherified, n-butyl etherified, iso-butyl etherified, etc.).

The SP value is generally called a solvability parameter among those skilled in the art, is a measure of the degree of hydrophilicity or hydrophobicity of the resin, and is also used for determining compatibility between resins. It is an important measure. The solubility parameter can be numerically quantified based on, for example, a turbidity measurement method (references: KW Shuh, DH Clarke J. Polymer. Sci., A-1, 5, 1671 (1967).). The solubility parameter in the present specification is a parameter obtained by the turbidity measurement method. The solubility parameter by the turbidity measurement method is, for example, that the resin solid content (predetermined mass) to be measured is dissolved in a certain amount of a good solvent (acetone or the like), and then a poor solvent such as water or hexane is added dropwise. It can be obtained by a known calculation method described in the above-mentioned references and the like from each droplet quantification until the above-mentioned resin is insolubilized and turbidity is generated in the solution.

The SP value of the amino resin (A) is 10.0 or less, preferably 9.0 to 9.8, and more preferably 9.1 to 9.5. When the SP value of the amino resin (A) is within the above range, the compatibility with the radical polymer (B) described later becomes good, and the appearance, adhesion to the polyolefin substrate, scratch resistance and printability are improved. An excellent coating film (cured film) can be obtained.

A preferred example of the amino resin (A) is a butyl etherified melamine resin from the viewpoint of excellent compatibility with a radical polymer (B) having a hydroxyl group, and a fully alkyl type butyl etherified melamine resin is particularly preferable.

The amino resin (A) can be used alone or in combination of two or more.

As a commercially available product of the amino resin (A), a butyl etherified melamine resin such as "Uban 20SB" or "Uban 520" manufactured by Mitsui Chemicals, Inc. can be used.

The polystyrene-equivalent weight average molecular weight of the amino resin (A) measured by GPC (gel permeation chromatography) is preferably 1,000 to 8,000, more preferably 1,200 to 7, It is 000, more preferably 1,500 to 6,000. The weight average molecular weight can be measured according to the method described in Examples described later (the same applies hereinafter). When the weight average molecular weight of the amino resin (A) is within the above range, a resin composition having an appropriate viscosity can be obtained, and a cured product having excellent compatibility, mechanical properties, smoothness, appearance and the like can be obtained. it can.

The amino resin (A) can preferably be obtained by condensing melamine, formaldehyde and an alcohol having an alkyl chain having 1 to 6 carbon atoms in the presence of an acid catalyst. As the alcohol, for example, methanol, ethanol, propanol, n-butanol, iso-butanol and the like are used, but as the alcohol, a hydrous alcohol may be used, and an alcohol different from the main alcohol may be used. A so-called mixed alcohol contained in a small amount may be used.

The melamine is not particularly limited, and may be synthesized by a conventionally known method or a commercially available product. The formaldehyde may be an aqueous solution or a solid paraformaldehyde. From the viewpoint of economy, paraformaldehyde having a formalin concentration of 80% by mass or more is preferable.

The solid content mass ratio of the amino resin (A) to the radical polymer (B) described later (amino resin (A) / radical polymer (B)) is, for example, 1/99 to 99/1, preferably 10 /. It is 90 to 95/5. When the content ratio of the amino resin (A) is within the above range, it is possible to surely improve the adhesion of the cured film to the substrate.

The solid content mass ratio of the amino resin (A) to the radical polymer (B) is preferably 50/50 to 99/1, more preferably 60/40 to 99/1, from the viewpoint of scratch resistance. More preferably, it is 60/40 to 95/5, and particularly preferably 65/35 to 90/10. When the solid content mass ratio of the amino resin (A) to the radical polymer (B) is in the above range, a coating film (cured film) having an excellent balance between the appearance of the coating film and the adhesion and scratch resistance can be obtained. In particular, when the solid content mass ratio of the amino resin (A) to the radical polymer (B) is 65/35 or more, the scratch resistance of the cured film can be improved. Further, when the solid content mass ratio of the amino resin (A) to the radical polymer (B) is 90/10 or less, the adhesion of the cured film can be improved.

The solid content mass ratio of the amino resin (A) to the radical polymer (B) is preferably 1/99 to 49/51, more preferably 10/90 to 40/60 from the viewpoint of printability. .. When the solid content mass ratio of the amino resin (A) to the radical polymer (B) is in the above range, excellent printability for ink can be reliably imparted to the cured film.

The solid content mass ratio of the amino resin (A) to the radical polymer (B) is preferably 20/80 to 70/30, more preferably 20 /, from the viewpoint of the balance between scratch resistance and printability. It is 80 to 60/40.

<Radical polymer with hydroxyl group)>
In the radical polymer (B) having a hydroxyl group used in the present invention (hereinafter, also simply referred to as "radical polymer (B))"), the radical polymer having no hydroxyl group is modified by a monomer having a hydroxyl group. Obtained by In other words, the radical polymer (B) having a hydroxyl group is a reaction product of a radical polymer having no hydroxyl group and a monomer having a hydroxyl group. In the following, the radical polymer before modification having no hydroxyl group will be referred to as the radical polymer before modification, and will be distinguished from the radical polymer (B) having a hydroxyl group.

The pre-modification radical polymer is a polymer of a radically polymerizable monomer, preferably a polymer of a radically polymerizable monomer containing at least an olefin (olefin polymer). The olefin is an example of a radically polymerizable monomer.

Examples of the pre-modification radical polymer (olefin-based polymer) include a polymer of an olefin having 2 to 20 carbon atoms, a polymer of an olefin having a plurality of double bonds, and a copolymer of an olefin and another radically polymerizable monomer. Can be mentioned. In other words, the radical polymer having no hydroxyl group is, for example, a polymer of an olefin having 2 to 20 carbon atoms, a polymer of an olefin having a plurality of double bonds, and a common weight of the olefin and another radically polymerizable monomer. It is at least one olefin-based polymer selected from the group consisting of coalescing.

Specifically, the polymer of an olefin having 2 to 20 carbon atoms contains a structural unit derived from an α-olefin having 4 to 20 carbon atoms. That is, the polymer of an olefin having 2 to 20 carbon atoms is a homopolymer composed of an α-olefin having 4 to 20 carbon atoms, or an α-olefin having 4 to 20 carbon atoms and an olefin having 2 to 3 carbon atoms. It is a copolymer.

Examples of the α-olefin having 4 to 20 carbon atoms include 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, and the like. Examples thereof include linear or branched α-olefins such as 1-hexadecene, 1-octadecene, and 1-eicosene.

The α-olefin having 4 to 20 carbon atoms is preferably a linear olefin having 4 to 10 carbon atoms, more preferably a linear olefin having 4 to 6 carbon atoms, and further preferably 1-butene. Can be mentioned. When 1-butene is used as the α-olefin having 4 to 20 carbon atoms, both good solvent solubility and excellent resin strength can be achieved at the same time. These can be used alone or in combination of two or more.

Examples of the olefin having 2 to 3 carbon atoms include ethylene and propylene, and preferably propylene.

Examples of the olefin having 2 to 20 carbon atoms include the above-mentioned olefin having 2 to 3 carbon atoms and the above-mentioned α-olefin having 4 to 20 carbon atoms. These can be used alone or in combination of two or more. The olefin having 2 to 20 carbon atoms is preferably ethylene, propylene or 1-butene, and more preferably a combination of propylene and 1-butene.

Specifically, the polymer of an olefin having a plurality of double bonds contains a structural unit derived from an olefin having a plurality of double bonds.

Examples of olefins having a plurality of double bonds include diolefins, triolefins, tetraolefins and the like. Specific examples of the olefin having a plurality of double bonds include 1,2-butadiene, 1,3-butadiene, 3-methyl-1,2-butadiene, 2-methyl-1,3-butadiene, 1,5-. Hexadiene and the like can be mentioned. 1,3-butadiene is preferably used because it has excellent compatibility with the amino resin (A) and the diluting solvent described later.

Specifically, the copolymer of the olefin and the other radically polymerizable monomer contains the above-mentioned structural unit derived from the olefin and the structural unit derived from the radically polymerizable monomer other than the olefin.

Examples of radically polymerizable monomers other than olefins include styrene and acrylonitrile.

The pre-denaturation radical polymer can be used alone or in combination of two or more.

Among the pre-modification radical polymers, a copolymer of an olefin and another radically polymerizable monomer is preferable, and a copolymer of an olefin having 2 to 20 carbon atoms and styrene is more preferable. More preferably, a copolymer of an olefin having 2 to 6 carbon atoms and styrene may be mentioned.

Examples of the copolymer of olefin having 2 to 6 carbon atoms and styrene include styrene / ethylene / 1-butene / styrene copolymer and styrene / ethylene / propylene / styrene copolymer.

The monomer having a hydroxyl group undergoes an addition reaction with the main chain of the pre-denaturation radical polymer. As a result, a hydroxyl group is introduced into the pre-denaturation radical polymer, and a radical polymer (B) having a hydroxyl group is prepared.

The monomer having a hydroxyl group has an ethylenically unsaturated double bond in addition to the hydroxyl group. Examples of the monomer having a hydroxyl group include hydroxyalkyl (meth) acrylate and the like. Examples of the (meth) acrylate include methacrylate and acrylate.

Examples of the hydroxyalkyl (meth) acrylate include hydroxyalkyl (meth) acrylate having a hydroxyalkyl group having 2 to 4 carbon atoms, and specifically, 2-hydroxyethyl (meth) acrylate and 3-hydroxy. Propyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate can be mentioned, and hydroxypropyl (meth) acrylate is preferable.

Hydroxyalkyl (meth) acrylate can be used alone or in combination of two or more.

As the radical polymer (B) having a hydroxyl group, particularly preferably, both 2-hydroxypropyl acrylate-modified styrene / ethylene / 1-butene / styrene copolymer and 2-hydroxypropyl acrylate-modified styrene / ethylene / propylene / styrene are used. Polymers can be mentioned.

The hydroxyl value of the radical polymer (B) is, for example, 10 to 250 mgKOH / g, preferably 20 to 200 mgKOH / g, more preferably 25 to 200 mgKOH / g, and even more preferably 30 to 150 mgKOH / g. .. The hydroxyl value can be measured according to the method described in Examples described later. When the hydroxyl value is within the above range, the compatibility with the amino resin (A) is good, a transparent coating film (cured film) is obtained, and the scratch resistance of the coating film is good.

The polystyrene-equivalent weight average molecular weight (Mw) of the radical polymer (B) measured by GPC is preferably 500 to 100,000, more preferably 1,000 to 95,000. When the Mw of the radical polymer (B) is within the above range, it is excellent in coatability, appearance of the coating film (cured film), strength, hardness, scratch resistance and the like.

The SP value of the radical polymer (B) is, for example, 7.0 to 9.5, preferably 8.0 to 9.0, and more preferably 8.2 to 8.9.

When the SP value of the radical polymer (B) is within the above range, the compatibility with the amino resin (A) becomes good, and the scratch resistance of the cured film described later can be improved.

The difference between the SP value of the amino resin (A) and the SP value of the radical polymer (B) is, for example, ± 3 or less, preferably ± 1.3 or less, more preferably ± 1.0 or less. , More preferably ± 0.5 or less.

Examples of commercially available products of the radical polymer (B) include "NISSO-PB GI-1000", "NISSO-PB GI-2000", "NISSO-PB GI-3000", and "NISSO" manufactured by Nippon Soda Corporation. -PB G-1000 "," NISSO-PB G-2000 "," NISSO-PB G-3000 "," Krasol LBH-P2000 "manufactured by CRAY VALLEY," Krasol HLBH-P2000 "and the like.

<Acid catalyst (C)>
As the acid catalyst (C), various known acid catalysts (C) can be used without particular limitation. Specific examples thereof include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid, and organic acids. Examples of the organic acids include carboxylic acids such as oxalic acid, acetic acid and formic acid; methanesulfonic acid, trifluoromethanesulfonic acid, isoprenesulfonic acid, camphorsulfonic acid, hexanesulfonic acid, octanesulfonic acid, nonanesulfonic acid and decanesulfonic acid. Organic sulfonic acids such as acids, hexadecane sulfonic acid, benzene sulfonic acid, p-toluene sulfonic acid, cumene sulfonic acid, dodecylbenzene sulfonic acid, naphthalene sulfonic acid, nonylnaphthalene sulfonic acid; methyl acid phosphate, ethyl acid phosphate, propyl acid phosphate , Isopropyl acid phosphate, butyl acid phosphate, butoxyethyl acid phosphate, octyl acid phosphate, 2-ethylhexyl acid phosphate, decyl acid phosphate, lauryl acid phosphate, stearyl acid phosphate, oleyl acid phosphate, behenyl acid phosphate, phenyl acid phosphate Acid phosphate, cyclohexyl acid phosphate, phenoxyethyl acid phosphate, alkoxypolyethylene glycol acid phosphate, bisphenol A acid phosphate, dimethyl acid phosphate, diethyl acid phosphate, dipropyl acid phosphate, diisopropyl acid phosphate, dibutyl acid phosphate, dioctyl acid phosphate, di- Organic phosphates such as 2-ethylhexyl acid phosphate, dilauryl acid phosphate, distearyl acid phosphate, diphenyl acid phosphate, bisnonylphenyl acid phosphate; thermal acid generation such as sulfonium salt, benzothiazolium salt, ammonium salt, phosphonium salt Examples include agents. These can be used alone or in combination of two or more.

The acid catalyst (C) is preferably p-toluenesulfonic acid because it has good compatibility with the amino resin (A), the radical polymer (B), and a diluting solvent described later.

The content of the acid catalyst (C) in the composition of the present invention is not particularly limited, but the amino resin (A) and the radical polymer can be compatible with each other in terms of both quick curing property and storage stability of the coating material described later. About 1 to 10 parts by mass is preferable, and about 2 to 8 parts by mass is more preferable with respect to 100 parts by mass of the total of (B).

<Fluorine-containing surface conditioner (D)>
The composition of the present invention preferably further contains a fluorine-containing surface conditioner (hereinafter, also referred to as “fluorine-containing surface conditioner (D))”).

The fluorine-containing surface conditioner (D) is a hydrophilic surfactant, and has, for example, a perfluoroalkyl group and a hydroxyl group.

The number of carbon atoms of the perfluoroalkyl group is, for example, 3 to 20, preferably 4 to 6. The perfluoroalkyl group is located, for example, at one molecular end of the fluorine-containing surface conditioner (D). The hydroxyl group is located, for example, at the other molecular end of the fluorine-containing surface conditioner (D).

Specific examples of the fluorine-containing surface conditioner (D) include a perfluoroalkylethylene oxide adduct.

The fluorine-containing surface conditioner (D) can be used alone or in combination of two or more.

Among the fluorine-containing surface conditioners (D), a perfluoroalkylethylene oxide adduct is preferably used.

As commercially available products of the fluorine-containing surface conditioner (D), "Surflon IF-HC125" and "Surflon S-242" manufactured by AGC Seimi Chemical Co., Ltd. can be used.

The content of the fluorine-containing surface modifier (D) is, for example, 0.05 to 40 parts by mass, preferably 0, based on 100 parts by mass of the total of the amino resin (A) and the radical polymer (B). .1 to 30 parts by mass, more preferably 0.1 to 3 parts by mass.

When the content of the fluorine-containing surface conditioner (D) is within the above range, the contact angle of water in the cured film, which will be described later, can be reduced, and the cured film ensures excellent printability for ink. Can be granted.

Further, the composition of the present invention may contain a surface conditioner that does not contain fluorine. Examples of the fluorine-free surface conditioner include silicone-based surfactants and sulfonic acid-based surfactants. The fluorine-free surface conditioner can be used alone or in combination of two or more. The fluorine-free surface conditioner may be used in combination with the fluorine-containing surface conditioner (D). The range of the content of the fluorine-free surface conditioner is the same as the range of the content of the fluorine-containing surface conditioner (D).

<Additive (E)>
The composition of the present invention may contain an additive (E), if necessary. Such additives are not particularly limited as long as the effects of the present invention are not impaired, and known additives can be used. Specifically, pigments, dyes, leveling agents, adhesion-imparting agents, stability improvers, foaming inhibitors, weather resistance improvers, armpit inhibitors, antioxidants, dispersants, wetting agents, tincture agents, UV absorbers, etc. Can be mentioned. The additive (E) may contain a Lewis acid and a protonic acid that do not fall into the category of the acid catalyst (C). Further, the additive (E) may be used alone or in combination of two or more.

The content of the additive (E) with respect to 100 parts by mass of the total amount of the composition of the present invention is usually 0 to 50 parts by mass, preferably 0 to 30 parts by mass. When the content of the additive (E) is within the above range, a thermosetting resin composition having excellent coatability, coating film physical properties and storage stability can be obtained.

<Solvent>
The composition of the present invention may be diluted with a solvent if necessary. The solvent (diluting solvent) is not particularly limited as long as the effect of the present invention is not impaired, and examples thereof include alkylbenzene-based solvents such as benzene, toluene and xylene, ethyl acetate, propyl acetate, butyl acetate, amyl acetate and methyl acetoacetate. Acetate-based solvents, dioxane, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and other ketone solvents, methanol, ethanol, isopropanol, 1-butanol, 2-butanol, isobutanol, 1-methoxy-2-propanol (PGM), etc. Examples include alcohol-based solvents and water. The solvent may be used alone or in combination of two or more.

From the viewpoint of solubility of the amino resin (A), the radical polymer (B) and the acid catalyst (C), it is preferable to use a solvent having a relatively low polarity, for example, methyl ethyl ketone, toluene, xylene, cyclohexanone and the like. ..

When the composition of the present invention is diluted with a solvent, the total content of the solvent with respect to the total amount of the diluted solution of the composition is preferably 10 to 95% by mass, more preferably 20.0 to 90.0% by mass. %, More preferably 40.0 to 85.0% by mass.

The thermosetting resin composition described above contains an alkyl etherified amino resin having an SP value of 10.0 or less, a radical polymer having a hydroxyl group, and an acid catalyst. Therefore, it is possible to form a cured film having excellent adhesion to the substrate described later.

The composition of the present invention can be suitably used for paint (coating material) applications. Specific examples of the use of the thermosetting resin composition include a coating material for printing.

The coating material for printing contains a thermosetting resin composition. The coating material for printing is applied to a base material as a pretreatment for printing and then cured to improve the printability of the base material for ink.

[Cured product and laminate]
The cured product of the present invention is characterized by comprising the composition of the present invention, and is usually in the form of a cured film. Further, the laminate of the present invention is characterized by containing a cured film made of the composition of the present invention, for example, a laminate containing a substrate and a cured film formed on the substrate, a substrate, and the like. Examples thereof include a laminated body in which a cured film and a printed layer are laminated in this order.

The method for producing a cured product (cured film) of the present invention is a step of heating the composition of the present invention to a temperature of 60 to 160 ° C., preferably 70 to 140 ° C. to cure it (hereinafter, also referred to as a “heating step”). ) Is included.

The heating time in the heating step is in the range of 20 seconds to 60 minutes, preferably in the range of 30 seconds to 40 minutes, depending on the heating temperature, and the heat resistance of the base material (object to be coated) and the production of the coating line. The temperature and time can be appropriately combined according to the sex.

After the step of applying the composition of the present invention to the substrate (object to be coated), the composition is heated (dried) under the same conditions as the heating step and cured to form a cured film. The laminate of the present invention can be produced.

Note that heating may be performed in two or more steps, and a post-curing step such as moving the laminate cured within the temperature and time range described above to another heat insulating chamber and heating it separately may be performed. The heating step may be performed under reduced pressure, or may be performed under an inert gas atmosphere or the like.

The contact angle of water in the cured film (cured product) is, for example, 20 to 90 °, preferably 20 to 89 °, more preferably 20 to 89 °, from the viewpoint of excellent printability of the print layer formed on the cured film. It is 50 to 89 °, more preferably 60 to 85 °. The contact angle can be measured according to the method described in Examples described later.

Examples of the base material (material to be coated) include a resin material, and examples of the resin material include vinyl chloride, polyethylene terephthalate, olefin polymer (for example, polyethylene, polypropylene, etc.), polycarbonate, ABS, PMMA, nylon, and polyamide. And those that have been surface-treated. Further, a substrate made of these materials coated with a primer, an intermediate coating, or a top coating coating can also be used, if necessary. Among such base materials, a base material made of an olefin polymer is preferable. The cured film made of the composition of the present invention is particularly excellent in adhesion to a substrate made of an olefin polymer, and is also excellent in appearance, scratch resistance and printability.

The method for applying the composition of the present invention to the substrate is not particularly limited, and is a spray coating method, a dip coating method, a roll coating method, a gravure coating method, a spin coating method, and a method using a bar coater or a doctor blade. And so on.

The thickness of the cured film is not particularly limited and may be appropriately selected depending on the desired application, but is preferably 0.05 to 40 μm, and more preferably 0.1 to 30 μm.

Examples of the use of the above-mentioned laminate include product labels, RFID tags, stickers, and the like, and preferably product labels.

As shown in FIG. 1, the product label 1 includes a base material 2, a coat layer 3, and a print layer 4 in this order. In other words, the commercial label 1 includes a laminate in which the base material 2, the coat layer 3, and the print layer 4 are laminated in this order.

The base material 2 is, for example, a resin base material made of the above-mentioned resin material.

The coat layer 3 is located on one surface of the base material 2 in the thickness direction. The coat layer 3 is the above-mentioned cured film and contains a cured product obtained by curing the above-mentioned thermosetting composition. To prepare the coat layer 3, the above-mentioned printing coating material is applied onto the base material 2 by the above-mentioned coating method, and then the coating film of the printing coating material is heated to the above-mentioned heating temperature to be cured.

The print layer 4 is located on the opposite side of the base material 2 with respect to the coat layer 3. The print layer 4 is located on one side of the coat layer 3 in the thickness direction. The print layer 4 is printed with a known ink by, for example, a known printing device.

As shown in FIGS. 2A and 2B, the commercial label 1 preferably has an adhesive region 2A and a non-adhesive region 2B.

Adhesive region 2A has adhesive strength (pressure sensitive adhesive strength). The adhesive region 2A is located on the other surface of the base material 2 in the thickness direction. The pressure-sensitive adhesive region 2A is a pressure-sensitive adhesive layer (pressure-sensitive adhesive layer) formed from a known pressure-sensitive adhesive (pressure-sensitive adhesive). The position of the adhesive region 2A is appropriately changed depending on the application.

The non-adhesive region 2B does not have adhesive strength (pressure sensitive adhesive strength). The non-adhesive region 2B is a portion other than the adhesive region 2A on the other surface of the base material 2 in the thickness direction. In the non-adhesive region 2B, the other surface of the base material 2 in the thickness direction is exposed.

Examples of such a product label 1 include a sticking label 11 (see FIG. 2A) that is directly attached to the product, a body-wrapping label (wrap round) 12 (see FIG. 2B) that is wrapped around the product, and the like.

As shown in FIG. 2A, the adhesive region 2A of the sticking label 11 is located, for example, at the center of the base material 2 on the other surface in the thickness direction. As shown in FIG. 2B, the adhesive region 2A of the body-wrapping label 12 is located, for example, at the end of the base material 2 on the other surface in the thickness direction.

Examples are shown below, and the present invention will be described in more detail, but the present invention is not limited thereto. Specific numerical values such as the compounding ratio (content ratio), physical property values, and parameters used in the following description are the compounding ratios (content ratio) corresponding to those described in the above-mentioned "Form for carrying out the invention". ), Physical property values, parameters, etc., can be replaced with the corresponding upper limit value (numerical value defined as "less than or equal to" or "less than") or lower limit value (numerical value defined as "greater than or equal to" or "excess"). it can. In addition, "part" and "%" are based on mass unless otherwise specified.

[Physical characteristics]
The methods for measuring the physical characteristics of the materials used in the examples and comparative examples are as follows.

<Weight average molecular weight>
The weight average molecular weight (Mw) of the amino resin (A) and the radical polymer (B) was measured by GPC under the following conditions.
Equipment: Showa Denko Corporation Shodex GPC-101
Detector: RI-71S
Column: Showa Denko Corporation GPC KF804L (Φ8.0 mm x 300 mm) x 3 Measurement temperature: 40 ° C
Eluent: THF (tetrahydrofuran)
Flow velocity: 1.0 ml / min
<Hydroxy group value>
The hydroxyl value of the radical polymer (B) having a hydroxyl group was measured according to JIS K 1557-1 (method for determining the hydroxyl value).

[Synthesis example]
<Synthesis Example 1> Synthesis of radical polymer having a hydroxyl group 2.4 kg of styrene / ethylene / 1-butene / styrene copolymer is added to 10 L of toluene, the temperature is raised to 112 ° C. in a nitrogen atmosphere, and 4 L of toluene is retained. I let you put it out. After raising the temperature to 165 ° C., 266 g of 2-hydroxypropyl acrylate and 67 g of di-tert-butyl peroxide were supplied to the system under stirring for 6 hours, followed by stirring at 165 ° C. for 1.5 hours. After cooling, toluene was supplied to the system to adjust the solid content to 22% by mass.

The hydroxyl value of the obtained 2-hydroxypropyl acrylate-modified styrene / ethylene / 1-butene / styrene copolymer was 40 mgKOH / g, and Mw was 90,000.

<Synthesis Example 2> Synthesis of radical polymer having a hydroxyl group 2.3 kg of styrene / ethylene / propylene / styrene copolymer was added to 10 L of toluene, the temperature was raised to 112 ° C. in a nitrogen atmosphere, and 4 L of toluene was distilled off. It was. After raising the temperature to 165 ° C., 265 g of 2-hydroxypropyl acrylate and 74 g of di-tert-butyl peroxide were supplied to the system under stirring for 5 hours, followed by stirring at 165 ° C. for 2 hours. After cooling, toluene was supplied to the system to adjust the solid content to 18% by mass.

The hydroxyl value of the obtained 2-hydroxypropyl acrylate-modified styrene / ethylene / propylene / styrene copolymer was 50 mgKOH / g, and Mw was 80,000.

<Synthesis Example 3> Synthesis of radical polymer containing no hydroxyl group 3 kg of propylene / 1-butene copolymer is added to 10 L of toluene, the temperature is raised to 145 ° C. in a nitrogen atmosphere, and the copolymer is dissolved in toluene. It was. Further, 382 g of maleic anhydride and 175 g of di-tert-butyl peroxide were supplied to the system under stirring for 4 hours, followed by stirring at 145 ° C. for 2 hours. After cooling, a large amount of acetone was added to precipitate the modified copolymer, which was filtered, washed with acetone, and then vacuum dried. The obtained polymer was adjusted by supplying a mixed solution of toluene and MEK to the system so that the solid content was 10% by mass.

The Mw of the obtained maleic anhydride-modified propylene / 1-butene copolymer was 110,000.

[material]
In Examples and Comparative Examples, the raw materials used when preparing the composition (coating material) and the base materials used when applying the composition are as follows.

<Alkyl etherified amino resin (A)>
(A-1) Butyl etherified melamine resin: "Uban 520" (manufactured by Mitsui Chemicals, Inc.)
-Solid content: 85% by mass
-Weight average molecular weight: 1,800
・ SP value: 9.2
(A-2) Butyl etherified melamine resin: "Uban 20SB" (manufactured by Mitsui Chemicals, Inc.)
・ Solid content: 50% by mass
-Weight average molecular weight: 5,500
・ SP value: 9.3
<Alkyl etherified amino resin (A') other than amino resin (A)>
(A'-1) Butyl etherified melamine resin: "Uban 225" (manufactured by Mitsui Chemicals, Inc.)
・ Solid content: 60% by mass
-Weight average molecular weight: 2,200
・ SP value: 10.2
(A'-2) Methyl etherified melamine resin: "Simel 303LF" (manufactured by Daicel Ornex)
-Solid content: 98% by mass
-Weight average molecular weight: 900
・ SP value: 13.8
<Radical polymer having a hydroxyl group (B)>
(B-1) Radical polymer obtained in Synthesis Example 1 ・ Solid content: 22% by mass
-Weight average molecular weight: 90,000
-Hydroxy group value: 50 mgKOH / g
・ SP value: 8.8
<Radical polymer having a hydroxyl group (B)>
(B-2) Radical polymer obtained in Synthesis Example 2 ・ Solid content: 16% by mass
-Weight average molecular weight: 80,000
-Hydroxy group value: 40 mgKOH / g
・ SP value: 8.9
(B-3) Hydrogenated product of hydroxyl group-containing butadiene polymer "NISSO-PB GI-1000" (manufactured by Nippon Soda Corporation)
・ Solid content: 100% by mass
-Weight average molecular weight: 4,400
-Hydroxy group value: 73 mgKOH / g
・ SP value: 8.6
<Radical polymer (B') other than radical polymer (B)>
(B'-1) Radical polymer obtained in Synthesis Example 3 ・ Solid content: 10% by mass
-Weight average molecular weight: 110,000
・ SP value: 8.8
(B'-2) Hydroxyl-free butadiene polymer "NISSO-PB BI-2000" (manufactured by Nippon Soda Corporation)
・ Solid content: 100% by mass
-Weight average molecular weight: 4,500
・ SP value: 9.0
<Acid catalyst (C)>
(C-1) "Paratoluenesulfonic acid monohydrate" (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.)
<Surface conditioner (D)>
(D-1) Fluorine-containing surface conditioner "Surflon IF-HC125" (manufactured by AGC Seichemical Co., Ltd.)
(D-2) Fluorine-containing surface conditioner "Surflon S-242" (manufactured by AGC Seichemical Co., Ltd.)
(D-3) Silicone-based surface conditioner "BYK-3560" (manufactured by BYK Co., Ltd.)
(D-4) Sulfonic acid-based surface conditioner "Perex TR" (manufactured by Kao Corporation)
<Base material>
-Biaxially stretched polypropylene film (210 mm x 297 mm x thickness 50 μm)
[Evaluation items and evaluation methods]
The evaluation of the coating film (cured film) prepared in Examples and Comparative Examples was performed as follows.

<Appearance of coating film>
The haze of the cured film immediately after curing was measured with a haze meter (NDH-4000 type, manufactured by Nippon Denshoku Kogyo Co., Ltd.). Further, the test piece obtained by curing the resin composition was visually evaluated according to the following criteria.
A: No foreign matter or whitening is seen and there is no abnormality (○).
B: Foreign matter and whitening are observed and there is an abnormality (x).

<Adhesion>
According to JIS K5400 8.5.2: 1990, use a knife for the coating film (cured film), make vertical and horizontal cuts with a width of 1 mm to reach the substrate, and then make cellophane on the surface. The state of the coating film after the adhesive tape was brought into close contact and instantly peeled off was evaluated according to the following criteria.
A: There is no peeling or chipping of the coating film (○).
B: There is some peeling and chipping of the coating film (Δ).
C: Peeling and chipping of the coating film are present on the entire surface (x).

<Scratch resistance>
The state of the coating film (cured film) after rubbing the cured film immediately after curing with steel wool (Bonster No. 0000, manufactured by Nippon Steel Wool Industry Co., Ltd.) once and for all was evaluated according to the following criteria.
A: The number of scratches is 0 to 5 (○).
B: The number of scratches is 6 to 10 (△).
C: The number of scratches is 11 or more (x).

<Printability>
The adhesion of the ink (copolymer of vinyl acetate and vinyl chloride) printed on the cured film and the contact angle of water with respect to the cured film were measured. The adhesion of the ink was evaluated according to JIS K5400 8.5.2: 1990. The contact angle of water was measured according to JIS R3257: 1999 “Method for testing the wettability of the substrate glass surface”. Then, the printability was evaluated according to the following criteria.
A: The contact angle of water is 89 ° or less, and there is no peeling or chipping of ink (◎).
B: The contact angle of water is 90 ° or more, and there is no peeling or chipping of ink (〇).
C: The contact angle of water is 89 ° or less, and there is some ink peeling and chipping (Δ).
D: The contact angle of water is 90 ° or more, and some ink is peeled off or chipped (Δ).
E: The contact angle of water is 89 ° or less, and there is peeling or chipping of ink on the entire surface (x).
F: The contact angle of water is 90 ° or more, and there is peeling or chipping of ink on the entire surface (x).

[Example 1]
20.2 g of the amino resin solution (A-1) and 52.0 g of the radical polymer solution (B-1) are mixed, and 22.2 g of a mixed solvent of toluene / MEK = 50/50 is added to sufficiently dissolve and mix. did. Next, 5.7 g of a solution of the acid catalyst (C-1) having a solid content of 25% with PGM (5 mass by mass with respect to 100 parts by mass of the total of the amino resin (A-1) and the radical polymer (B-1)). Part) Addition to prepare a thermosetting resin composition having a non-volatile content of 30% by mass. The obtained composition was coated on an OPP film having a film thickness of 50 μm with a bar coater # 14, and heated in a warm air dryer for 120 seconds under the condition of 1 minute to prepare a cured film having a film thickness of about 3 μm. Various tests were carried out. The results are shown in Table 1.

[Examples 2 to 6, 11 to 13, Comparative Examples 1 to 6]
A thermosetting resin composition was prepared in the same manner as in Example 1 except that the compositions shown in Tables 1 to 3 were substituted. The results of various tests are shown in Tables 1 to 3.

[Example 7]
A thermosetting resin composition was prepared in the same manner as in Example 3 except that 0.5 parts by mass of the surface conditioner (D-1) was added to the thermosetting resin composition. The results of various tests are shown in Table 2.

[Example 8]
The radical polymer solution (B-1) was changed to the radical polymer solution (B-2), and 0.5 parts by mass of the surface conditioner (D-2) was added to the thermosetting resin composition. A thermosetting resin composition was prepared in the same manner as in Example 3 except for the above. The results of various tests are shown in Table 2.

[Example 9]
The radical polymer solution (B-1) was changed to the radical polymer solution (B-3), and 0.5 parts by mass of the surface conditioner (D-3) was added to the thermosetting resin composition. A thermosetting resin composition was prepared in the same manner as in Example 3 except for the above. The results of various tests are shown in Table 2.

[Example 10]
A thermosetting resin composition was prepared in the same manner as in Example 9 except that the surface conditioner (D-3) was changed to the surface conditioner (D-4). The results of various tests are shown in Table 2.

[Example 14]
A thermosetting resin composition was prepared in the same manner as in Example 12 except that 0.5 parts by mass of the surface conditioner (D-1) was added to the thermosetting resin composition. The results of various tests are shown in Table 2.

[Example 15]
A thermosetting resin composition was prepared in the same manner as in Example 13 except that 0.5 parts by mass of the surface conditioner (D-2) was added to the thermosetting resin composition. The results of various tests are shown in Table 2. The compositions in Tables 1 to 3 are all values in terms of solid content.

Although the above invention has been provided as an exemplary embodiment of the present invention, this is merely an example and should not be construed in a limited manner. Modifications of the present invention that will be apparent to those skilled in the art are included in the claims below.

The thermosetting resin composition of the present invention can be used for various industrial products, and can be suitably used for, for example, paint (coating material) applications. The cured product and laminate of the present invention can be used for various industrial products, and can be suitably used for, for example, commercial labels.

1 Product label 2 Base material 2A Adhesive area 2B Non-adhesive area 3 Coat layer 4 Printing layer

Claims

(A) An alkyl etherified amino resin having a solubility parameter δ (SP value) of 10.0 or less,
(B) A radical polymer having a hydroxyl group and
(C) A thermosetting resin composition containing an acid catalyst.
The thermosetting resin composition according to claim 1, wherein the mass ratio of the alkyl etherified amino resin to the radical polymer is in the range of 50/50 to 99/1.
The thermosetting resin composition according to claim 1, wherein the mass ratio of the alkyl etherified amino resin to the radical polymer is in the range of 1/99 to 49/51.
The thermosetting resin composition according to any one of claims 1 to 3, wherein the alkyl etherified amino resin is a butyl etherified melamine resin.
The thermosetting resin composition according to any one of claims 1 to 4, wherein the radical polymer has a hydroxyl value of 20 to 200 mgKOH / g.
The thermosetting resin composition according to any one of claims 1 to 5, wherein the solubility parameter δ (SP value) of the radical polymer is 8.0 to 9.0.
The radical polymer is a reaction product of a radical polymer having no hydroxyl group and a monomer having a hydroxyl group.
The radical polymer having no hydroxyl group is a group consisting of a polymer of an olefin having 2 to 20 carbon atoms, a polymer of an olefin having a plurality of double bonds, and a copolymer of an olefin and another radically polymerizable monomer. The thermosetting resin composition according to any one of claims 1 to 6, which is at least one polymer selected from the above.
The thermosetting resin composition according to any one of claims 1 to 7, wherein the acid catalyst is paratoluenesulfonic acid.
Further, any of claims 1 to 8, wherein the surface conditioner containing (D) fluorine is contained in an amount of 0.1 to 30 parts by mass with respect to 100 parts by mass of the total of the alkyl etherified amino resin and the radical polymer. The thermosetting resin composition according to item 1.
A coating material for printing containing the thermosetting resin composition according to any one of claims 1 to 9.
A cured product comprising the thermosetting resin composition according to any one of claims 1 to 9.
The cured product according to claim 11, wherein the contact angle of water is 20 to 89 ° or less.
A laminate in which a base material, a cured film, and a printed layer are laminated in this order, and the cured film contains the cured product according to claim 11.
The laminate according to claim 13, wherein the base material is an olefin polymer.
Including the laminate according to claim 13 or 14,
The base material is a label containing an adhesive region and a non-adhesive region.
After the step of applying the thermosetting resin composition according to any one of claims 1 to 9 to a substrate,
A method for producing a laminate, which comprises a step of heating the thermosetting resin composition to 60 to 160 ° C. and curing it to form a cured film.