JP6943391B2 - Coating composition - Google Patents

Description

The present invention relates to a coating composition capable of forming a coating film having excellent durability and adhesion to a substrate.

Conventionally, polymers having various vinyl-based monomers such as polystyrene, poly (meth) acrylate, polyacrylamide, and copolymers of the monomers constituting these polymers have been various types such as paints, gravure inks, and inkjet inks. It is used as a coating component to be blended in a coating composition that forms a coating film (coating) that covers the surface of a base material. Such coating compositions include, for example, buildings, building materials, structures, automobiles, vehicles, electrical equipment, precision equipment, food packaging, etc., which are composed of materials such as wood, plastic, rubber, metal, pottery, glass, and leather. Surface protection of food containers, furniture, battery materials, electronic parts, mechanical parts, etc., designability, material durability improvement, aesthetics, thermal conductivity, antistatic property, conductivity, stain resistance, It is used for the purpose of imparting corrosion resistance.

A wide variety of polymers have been developed to be blended as coating components in coating compositions. For example, a fluorine-based graft copolymer obtained by using a vinyl-based monomer containing a fluorine atom and a silicone-based macromonomer (Patent Document 1), or a silicone acrylic graft copolymer resin blended in a coating agent for leather. (Patent Document 2) has been proposed. Further, a resin containing a reaction product of a polymer such as acrylic and a polyolefin having a functional group (Patent Document 3) and a polymer in which a branch segment having a blocked polyfluoroalkyl group is bonded to a trunk segment (Patent Document 3). 4) has been proposed.

Further, a graft copolymer (Patent Document 5) having a main chain containing a perfluoro (meth) acrylate as a monomer component and a side chain containing a non-fluoropolymer as a monomer component, perfluoro (meth) acrylate, and the like. A graft copolymer having a side chain composed of a polymer composed of a polymer and a main chain composed of a polymer composed of other radically polymerizable monomers (Patent Document 6) has been proposed.

JP-A-2015-13911 Japanese Unexamined Patent Publication No. 2016-138242 Japanese Unexamined Patent Publication No. 2015-232149 Special Publication No. 63-21715 Japanese Unexamined Patent Publication No. 6-228534 Japanese Unexamined Patent Publication No. 9-67417

However, it balances durability such as abrasion resistance, water resistance, oil resistance, abrasion resistance, chemical resistance, solvent resistance, and stain resistance, and properties such as adhesion (adhesiveness) to various substrates. A coating composition capable of forming a well-combined coating film has not been found so far.

The present invention has been made in view of the problems of the prior art, and the subject thereof is a coating film (coating film) having characteristics such as durability and adhesion to a substrate in a well-balanced manner. ) To provide a coating composition capable of forming.

That is, according to the present invention, the coating composition shown below is provided.
[1] A coating composition containing a solvent and a polymer, wherein the polymer is a graft-type polymer containing 80% by mass or more of a structural unit represented by the following general formula (1), and the gel perme of the polymer. A coating composition having a polystyrene-equivalent number average molecular weight of 10,000 or more and 1,000,000 or less as measured by ion chromatography.

（前記一般式（１）中、Ｒ₁は、水素原子又はメチル基を示し、Ｘは、Ｏ又はＮＨを示し、Ｒ₂は、任意の有機基を示し、Ｒ₃及びＲ₄は、それぞれ独立に水素原子、アルキル基、アリール基、又はアシル基を示すとともに、Ｒ₃及びＲ₄が結合している炭素原子は第３級炭素原子又は第４級炭素原子であり、ｎは、任意の繰り返し数を示し、Ｐｏｌｙｍｅｒは、（メタ）アクリル酸系モノマー、（メタ）アクリルアミド系モノマー、芳香族ビニル系モノマー、及び（メタ）アクリロニトリルからなる群より選択される少なくとも一種のグラフトモノマーに由来する構成単位を含むグラフト鎖を示す）

(In the general formula (1), R ₁ represents a hydrogen atom or a methyl group, X represents O or NH, R ₂ represents an arbitrary organic group, and R ₃ and R ₄ are independent of each other. Indicates a hydrogen atom, an alkyl group, an aryl group, or an acyl group, and the _{carbon atom to which R 3 and R 4} are bonded is a tertiary carbon atom or a quaternary carbon atom, and n is an arbitrary repetition. Indicating a number, Polymer is a structural unit derived from at least one graft monomer selected from the group consisting of (meth) acrylic acid-based monomers, (meth) acrylamide-based monomers, aromatic vinyl-based monomers, and (meth) acrylonitrile. Indicates a graft chain containing

[2] The graft monomer is a reactive group of any one of a carboxy group, a phosphoric acid group, a phosphoric acid ester group, a hydroxyl group, a glycidyl group, an isocyanate group, a blocked isocyanate group, an alkoxysilyl group, and a (meth) acryloyl group. The coating composition according to the above [1].
[3] The polymer contains two or more structural units having different Polymers from each other in the general formula (1), and the two or more structural units are represented by the following general formula (1-A). The coating composition according to the above [1], which comprises a structural unit A and a structural unit B represented by the following general formula (1-B).

（前記一般式（１−Ａ）中、Ｒ₁〜Ｒ₄、Ｘ、及びｎは、前記一般式（１）中のＲ₁〜Ｒ₄、Ｘ、及びｎと同義であり、Ｐｏｌｙｍｅｒ Ａは、反応性基を有しない第１のグラフトモノマーに由来する構成単位からなるグラフト鎖を示す）

(In the general formula _{(1-A), R 1} ~R 4, X, and n, R ₁ to R _4, X in the general formula (1), and has the same meaning as n, Polymer A is Indicates a graft chain consisting of a structural unit derived from a first graft monomer having no reactive group)

（前記一般式（１−Ｂ）中、Ｒ₁〜Ｒ₄、Ｘ、及びｎは、前記一般式（１）中のＲ₁〜Ｒ₄、Ｘ、及びｎと同義であり、Ｐｏｌｙｍｅｒ Ｂは、カルボキシ基、リン酸基、リン酸エステル基、水酸基、グリシジル基、イソシアネート基、ブロック化イソシアネート基、アルコキシシリル基、及び（メタ）アクリロイル基のいずれかの反応性基を有する第２のグラフトモノマーに由来する構成単位を含むグラフト鎖を示す）

(In the general formula _{(1-B), R 1} ~R 4, X, and n, R ₁ to R _4, X in the general formula (1), and has the same meaning as n, Polymer B is A second graft monomer having a reactive group of any one of a carboxy group, a phosphoric acid group, a phosphoric acid ester group, a hydroxyl group, a glycidyl group, an isocyanate group, a blocked isocyanate group, an alkoxysilyl group, and a (meth) acryloyl group. Indicates a graft chain containing the structural unit from which it is derived)

[4] The coating composition according to the above [2] or [3], which further contains a cross-linking agent having two or more groups capable of reacting with the reactive group.

According to the present invention, it is possible to provide a coating composition capable of forming a coating film (coating film) having characteristics such as durability and adhesion to a substrate in a well-balanced manner.

It is a schematic diagram which shows an example of the crosslinked structure of a graft type polymer. It is a schematic diagram which shows another example of the crosslinked structure of a graft type polymer.

<Coating composition>
Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments. The coating composition of the present invention contains a solvent and a polymer. The polymer is a graft-type polymer containing 80% by mass or more of the structural units represented by the following general formula (1).

（前記一般式（１）中、Ｒ₁は、水素原子又はメチル基を示し、Ｘは、Ｏ又はＮＨを示し、Ｒ₂は、任意の有機基を示し、Ｒ₃及びＲ₄は、それぞれ独立に水素原子、アルキル基、アリール基、又はアシル基を示すとともに、Ｒ₃及びＲ₄が結合している炭素原子は第３級炭素原子又は第４級炭素原子であり、ｎは、任意の繰り返し数を示し、Ｐｏｌｙｍｅｒは、（メタ）アクリル酸系モノマー、（メタ）アクリルアミド系モノマー、芳香族ビニル系モノマー、及び（メタ）アクリロニトリルからなる群より選択される少なくとも一種のグラフトモノマーに由来する構成単位を含むグラフト鎖を示す）

(In the general formula (1), R ₁ represents a hydrogen atom or a methyl group, X represents O or NH, R ₂ represents an arbitrary organic group, and R ₃ and R ₄ are independent of each other. Indicates a hydrogen atom, an alkyl group, an aryl group, or an acyl group, and the _{carbon atom to which R 3 and R 4} are bonded is a tertiary carbon atom or a quaternary carbon atom, and n is an arbitrary repetition. Indicating a number, Polymer is a structural unit derived from at least one graft monomer selected from the group consisting of (meth) acrylic acid-based monomers, (meth) acrylamide-based monomers, aromatic vinyl-based monomers, and (meth) acrylonitrile. Indicates a graft chain containing

(Graft type polymer)
The graft-type polymer contains 80% by mass or more, preferably 90% by mass or more, and more preferably 100% by mass of the structural unit represented by the general formula (1). That is, since the graft-type polymer contains the structural unit represented by the general formula (1) as a main component, it is a polymer capable of exhibiting unprecedented performance. This graft-type polymer is called, for example, a bottle-brush type polymer or a cylinder-type polymer, and since the chain represented by Polymer in the general formula (1) is bonded to the main chain at high density, it can be used in a good solvent. It can be highly elongated and oriented to match the length of the stretched chain. This is expected to exhibit various properties such as compression resistance, super-friction properties, clear size exclusion effect, biocompatibility, and excellent mechanical properties. Then, by using the coating composition of the present invention containing this graft-type polymer as a film-forming component, a coating film (coating film) having unprecedented characteristics can be formed.

In the general formula (1), since R ₁ is a hydrogen atom or a methyl group and X is O or NH, the main chain of the grafted polymer is a (meth) acryloyloxy group, a (meth) acryloylamino group, or the like. It is formed by polymerizing the unsaturated groups of. That is, the graft-type polymer has a structure in which a graft chain (side chain) represented by Polymer is grafted to the main chain via an arbitrary linking group.

The graft-type polymer contains a structural unit (other structural units) other than the structural unit represented by the general formula (1) as long as it contains 80% by mass or more of the structural unit represented by the general formula (1). You may. As the monomer constituting the other structural unit, a conventionally known monomer having an unsaturated bond such as a vinyl group, a vinylidene group, and a vinylene group and capable of radical polymerization can be used.

In the general formula (1), n (number of repetitions) is preferably 2 or more, and preferably 10 or more. By setting the number of n to 2 or more, the main chain can more easily function as a polymer. The structural unit represented by the general formula (1) may be a homopolymer or a random polymer containing other structural units. Furthermore, it may have a structure such as a block structure, a gradient structure, a graft structure, or a multi-branched structure.

The Polymer in the general formula (1) is a (grafted) graft chain bonded to the main chain, and is a (meth) acrylic acid-based monomer, a (meth) acrylamide-based monomer, an aromatic vinyl-based monomer, and a (meth) acrylonitrile. Includes structural units derived from at least one graft monomer selected from the group consisting of.

Examples of the (meth) acrylic acid-based monomer include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, 2-methylpropane (meth) acrylate, and t. -Butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate , Lauryl (meth) acrylate, tetradecyl (meth) acrylate, octadecyl (meth) acrylate, behenyl (meth) acrylate, isostearyl (meth) acrylate, cyclohexyl (meth) acrylate, t-butylcyclohexylmethyl (meth) acrylate, Isobolonyl (meth) acrylate, trimethylcyclohexyl (meth) acrylate, cyclodecyl (meth) acrylate, cyclodecylmethyl (meth) acrylate, benzyl (meth) acrylate, t-butylbenzotriazolephenylethyl (meth) acrylate, phenyl (meth) acrylate , Acrylates such as naphthyl (meth) acrylates and allyl (meth) acrylates, alicyclic, aromatic alkyl (meth) acrylates;

2-Hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, cyclohexanedimethanol mono (Meta) acrylate having a hydroxyl group such as (meth) acrylate and cyclohexanediol mono (meth) acrylate;

Poly (n = 2 or more) ethylene glycol mono (meth) acrylate, poly (n = 2 or more) propylene glycol mono (meth) acrylate, poly (n = 2 or more) tetramethylene glycol mono (meth) acrylate, mono or poly ( n = 2 or more) Ethylene glycol mono or poly (n = 2 or more) Propylene glycol Random copolymer mono (meth) acrylate, mono or poly (n = 2 or more) ethylene glycol mono or poly (n = 2 or more) propylene glycol block Mono (meth) acrylates of polyalkylene glycols such as mono (meth) acrylates of copolymers;

(Poly) ethylene glycol monomethyl ether (meth) acrylate, (poly) ethylene glycol monooctyl ether (meth) acrylate, (poly) ethylene glycol monolauryl ether (meth) acrylate, (poly) ethylene glycol monostearyl ether (meth) acrylate , (Poly) ethylene glycol monooleyl ether (meth) acrylate, (poly) ethylene glycol monostearic acid ester (meth) acrylate, (poly) ethylene glycol monononylphenyl ether (meth) acrylate, (poly) propylene glycol monomethyl ether (poly) Meta) acrylate, (poly) propylene glycol monoethyl ether (meth) acrylate, (poly) propylene glycol monooctyl ether (meth) acrylate, (poly) propylene glycol monolauryl ether (meth) acrylate, (poly) ethylene glycol (poly) ) Mono (meth) acrylate of (polyalkylene) glycol monoalkyl, alkylene, alkyne ether or ester such as propylene glycol monomethyl ether (meth) acrylate;

Monomer having a carboxy group such as a monomer obtained by reacting acrylic acid, methacrylic acid, hydroxyalkyl (meth) acrylate with an acid anhydride such as maleic anhydride, succinic anhydride, phthalic anhydride; ethyl sulfonate (meth) acrylate and the like. Sulfonic acid group-containing monomer; (di, tri) (meth) acryloyloxyethyl phosphate or other phosphate group-containing monomer;

Oxygen atom-containing monomers such as glycidyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, oxetanylmethyl (meth) acrylate, morpholino (meth) acrylate, methylmorpholino (meth) acrylate, methylmorpholinoethyl (meth) acrylate;

2-Aminoethyl (meth) acrylate, t-butylaminoethyl (meth) acrylate, tetramethylpiperidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, pentamethylpiperidyl (meth) acrylate, N-ethylmorpholino (meth) acrylate, trimethylaminoethyl (meth) acrylate, diethylmethylaminoethyl (meth) acrylate, benzyldimethylaminoethyl (meth) acrylate, trimethylaminoethyl (meth) acrylate methyl sulfate, etc. Monomer having an amino group;

Examples thereof include (meth) acryloyloxyethyl isocyanate, (meth) acryloyloxyethoxyethyl isocyanate, and nitrogen atom-containing monomers such as blocked isocyanate-containing (meth) acrylate in which the isocyanate groups of these monomers are blocked with caprolactone or the like. ..

Examples of the (meth) acrylamide-based monomer include (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-hydroxyethyl (meth) acrylamide, and (meth) acryloyl morpholine. Can be mentioned.

Examples of the aromatic vinyl-based monomer include styrene, vinyltoluene, vinylhydroxybenzene, chloromethylstyrene, vinylnaphthalene, vinylbiphenyl, vinylethylbenzene, vinyldimethylbenzene, α-methylstyrene and the like.

In the general formula (1), R ₂ represents an arbitrary organic group. Optional organic groups include alkylene groups such as ethylene and propylene; cycloalkylene groups such as cyclohexylene groups; poly (n = 2 or more) alkylene glycol groups; hydroxy at the terminal hydroxyl groups of poly (n = 2 or more) alkylene glycol groups. A polyester group obtained by reacting or polymerizing an alkylcarboxylic acid; an organic group in which a group such as a hydroxyl group or an acyl group is bonded to an arbitrary position of these groups; a group in which these groups are bonded by a urethane bond, a urea bond, or the like. be able to. Among them, alkylene groups such as ethylene, propylene, butylene and methyl propylene; polyethylene glycol and propylene glycol are preferable because of their high versatility and easy availability.

In the general formula (1), R ₃ and R ₄ independently represent a hydrogen atom, an alkyl group, an aryl group, or an acyl group, respectively. The _{carbon atom to which R 3} and R ₄ are bonded is a tertiary carbon atom or a quaternary carbon atom. Specific examples of the ester group bonded to R ₂ include groups represented by the following formulas (1-1) to (1-6). In addition, "*" in the following formulas (1-1) to (1-6) indicates the coupling position with _{R 2 in the general formula (1).}

The polystyrene-equivalent number average molecular weight (Mn) of the grafted polymer measured by gel permeation chromatography (GPC) is 10,000 or more and 1,000,000 or less, preferably 20,000 or more and 800,000 or less. , More preferably 30,000 or more and 500,000 or less. If the number average molecular weight of the grafted polymer is less than 10,000, the performance derived from the specific structure of the grafted polymer will not be exhibited. On the other hand, if the number average molecular weight of the graft-type polymer is more than 1,000,000, the viscosity of the coating composition becomes too high, and it becomes difficult to apply it to a substrate or the like.

In the graft type polymer, when the molecular weight of Polymer in the general formula (1) is small and the number of graft chains is large; and when the molecular weight of Polymer in the general formula (1) is large and the number of graft chains is small; It may be any of.

The graft monomer constituting the constituent unit of the graft chain represented by Polymer in the general formula (1) is a carboxy group, a phosphoric acid group, a phosphoric acid ester group, a hydroxyl group, a glycidyl group, an isocyanate group, a blocked isocyanate group, or an alkoxy. It preferably has a reactive group of either a silyl group or a (meth) acryloyl group. That is, by using a graft-type polymer in which a graft chain having such a reactive group is bonded to the main chain, a coating composition capable of forming a coating film having improved adhesion to various substrates can be obtained. be able to. Furthermore, a three-dimensional network structure can be formed by cross-linking the reactive groups. Therefore, it is possible to obtain a coating composition capable of forming a coating film having improved mechanical and chemical physical characteristics.

The graft monomer having a reactive group can be appropriately selected and used from the above-mentioned specific examples of the graft monomer. As the graft monomer having a phosphoric acid ester group, a monomer obtained by esterifying the phosphoric acid group of the graft monomer having a phosphoric acid group can be used. Further, the graft monomer having a (meth) acryloyl group is, for example, reacting a graft monomer having a carboxy group with glycidyl (meth) acrylate; reacting a graft monomer having a hydroxyl group with isocyanatoethyl (meth) acrylate; a glycidyl group. It can be obtained by reacting (meth) acrylic acid with a graft monomer having the above;

The amount of the structural unit derived from the graft monomer having a reactive group in the graft chain is not particularly limited, and may be appropriately set in consideration of the crosslink density, the physical properties of the polymer, and the like. Specifically, it is preferably 0.5 to 100% by mass, and more preferably 3 to 30% by mass.

FIG. 1 is a schematic view showing an example of a crosslinked structure of a grafted polymer. The graft-type polymer 10 shown in FIG. 1 has a main chain 2 and a graft chain 4 having a reactive group attached to the main chain 2. By cross-linking the graft-type polymer 10 with a reactive group, a cross-linked structure can be formed.

Further, the graft type polymer contains two or more kinds of structural units having different Polymers in the general formula (1), and these two or more kinds of structural units are represented by the following general formula (1-A). It is preferable to include the unit A and the structural unit B represented by the general formula (1-B).

（前記一般式（１−Ａ）中、Ｒ₁〜Ｒ₄、Ｘ、及びｎは、前記一般式（１）中のＲ₁〜Ｒ₄、Ｘ、及びｎと同義であり、Ｐｏｌｙｍｅｒ Ａは、反応性基を有しない第１のグラフトモノマーに由来する構成単位からなるグラフト鎖を示す）

(In the general formula _{(1-A), R 1} ~R 4, X, and n, R ₁ to R _4, X in the general formula (1), and has the same meaning as n, Polymer A is Indicates a graft chain consisting of a structural unit derived from a first graft monomer having no reactive group)

（前記一般式（１−Ｂ）中、Ｒ₁〜Ｒ₄、Ｘ、及びｎは、前記一般式（１）中のＲ₁〜Ｒ₄、Ｘ、及びｎと同義であり、Ｐｏｌｙｍｅｒ Ｂは、カルボキシ基、リン酸基、リン酸エステル基、水酸基、グリシジル基、イソシアネート基、ブロック化イソシアネート基、アルコキシシリル基、及び（メタ）アクリロイル基のいずれかの反応性基を有する第２のグラフトモノマーに由来する構成単位を含むグラフト鎖を示す）

(In the general formula _{(1-B), R 1} ~R 4, X, and n, R ₁ to R _4, X in the general formula (1), and has the same meaning as n, Polymer B is A second graft monomer having a reactive group of any one of a carboxy group, a phosphoric acid group, a phosphoric acid ester group, a hydroxyl group, a glycidyl group, an isocyanate group, a blocked isocyanate group, an alkoxysilyl group, and a (meth) acryloyl group. Indicates a graft chain containing the structural unit from which it is derived)

Since Polymer B in the general formula (1-B) is a graft chain having a reactive group, it can be immobilized by a cross-linking reaction or the like. Therefore, Polymer B functions as a graft chain for forming a coating film having improved mechanical and chemical physical characteristics. On the other hand, Polymer A in the general formula (1-A) is a graft chain having substantially no reactive group, and therefore is not substantially immobilized by a cross-linking reaction or the like and is used as a free chain. Can exist. Then, even if Polymer B is fixed by a cross-linking reaction or the like, Polymer A existing in a free chain state dissolves in a solvent or swells with a solvent, so that a coating film which is a cured film in which a soft state is maintained is formed. Will be done. Further, the Polymer A existing in a free chain state can impart properties such as water repellency and oil repellency to the formed coating film.

FIG. 2 is a schematic view showing another example of the crosslinked structure of the grafted polymer. The graft-type polymer 20 shown in FIG. 2 has a main chain 12 and a graft chain having no reactive group (Polymer A) and a graft chain having a reactive group (Polymer B) bonded to the main chain 12. Have. By cross-linking this graft-type polymer 20, Polymer B having a reactive group can be immobilized, and a cross-linked structure in which Polymer A having no reactive group exists as a free chain can be formed.

The ratio of the structural unit A to the structural unit B contained in the graft-type polymer is not particularly limited, and may be appropriately set so as to form a coating film having desired physical properties. For example, in order to form a coating film that does not easily swell with a solvent, the ratio of the structural unit B containing Polymer B having a reactive group may be increased. On the other hand, in order to form a coating film that does not dissolve in a solvent but tends to swell and form a gel, the ratio of the structural unit A containing Polymer A having no reactive group may be increased.

The graft-type polymer can further contain structural units (constituent units C, D, E, ...) Different from the above-mentioned structural unit A and structural unit B. The graft-type polymer containing the structural units A, B, C, D, E, ... Can be represented by the following general formula (X).

（前記一般式（Ｘ）中、Ｒ₁〜Ｒ₄、Ｘ、及びｎは、前記一般式（１）中のＲ₁〜Ｒ₄、Ｘ、及びｎと同義であり、Ｐｏｌｙｍｅｒ Ａ〜Ｅは、相互に異なるグラフト鎖を示す）

(In the general formula (X), R ₁ to R _4, X, and n, R ₁ to R _4, X in the general formula (1), and has the same meaning as n, Polymer A-E is, Show different graft chains)

Polymers A to E in the general formula (X) are graft chains that are different from each other. By subsequently binding a plurality of different types of graft chains to the main chain, a graft-type polymer having various desired properties can be obtained. For example, a graft-type polymer in which multiple types of graft chains having different hardness (softness) are introduced; a graft-type polymer in which multiple types of graft chains having different glass transition points and melting points are introduced; Graft-type polymer with multiple graft chains introduced; Graft-type polymer with multiple graft chains with different water solubility; Graft-type polymer with multiple graft chains with different compatibility; Graft-type polymer in which multiple types of graft chains with different hydrophilicity (hydrophobicity) are introduced; Gradient-type polymer in which multiple types of graft chains with different bulk densities are introduced; Multiple types of graft chains with different ionicity Introduced graft-type polymer; graft-type polymer in which multiple types of graft chains with different light absorption wavelengths are introduced; graft-type polymer in which multiple types of graft chains with different photocrosslinkability are introduced; (hydration) Graft-type polymer with multiple types of graft chains with different degradability introduced; graft-type polymer with dye-bound graft chain and non-dye-bonded graft chain introduced; graft chain with inorganic groups bonded Graft-type polymer with graft chains that do not have inorganic groups bonded to each other; Graft-type polymer with multiple types of graft chains with different gas permeability; Multiple types of graft chains with different thermal conductivity Examples thereof include a graft-type polymer in which is introduced.

Further, the type of functional group contained in the graft chain, the number of graft chains, the mutual ratio of the graft chains, the type and number of the monomers constituting the graft chain, etc. are appropriately set; and the molecular weight of the graft chain is appropriately set; You can also do it.

(Manufacturing of graft type polymer)
The graft-type polymer used in the coating composition of the present invention has the following general formula (2) in the presence of at least one of a quaternary ammonium salt and a quaternary phosphonium salt producing, for example, chlorine ion, bromine ion, or iodine ion. ), And at least selected from the group consisting of (meth) acrylic acid-based monomers, (meth) acrylamide-based monomers, aromatic vinyl-based monomers, and (meth) acrylonitrile. It can be produced by polymerizing a kind of graft monomer.

（前記一般式（２）中、Ｒ₁〜Ｒ₄及びＸは、前記一般式（１）中のＲ₁〜Ｒ₄及びＸと同義であり、Ｙは、塩素原子、臭素原子、又はヨウ素原子を示す）

(In the general formula (2), R ₁ to R ₄ and X have the same meanings as R ₁ to R ₄ and X in the general formula (1), Y is a chlorine atom, a bromine atom, or iodine atom Show)

In the general formula (2), the group (halogen atom) represented by Y becomes a radical and is eliminated, and the carbon atom to which the halogen atom is bonded becomes a radical. Then, the radical of the generated carbon atom reacts with the graft monomer to generate a radical. The desorbed halogen radicals immediately bind to the generated radicals to stabilize them. By stabilizing the generated radicals in this way, it becomes difficult for a termination reaction due to coupling between radicals to occur. As a result, the graft monomers are sequentially polymerized to form the graft chain represented by Polymer in the general formula (1), and the desired graft-type polymer can be obtained.

By the way, it is also possible to produce the desired graft-type polymer by polymerizing the macromonomer represented by the following general formula (4). However, since the reaction site of the macromonomer represented by the following general formula (4) exists at the polymer terminal, the macromonomer that does not polymerize tends to remain, and the molecular weight of the obtained polymer does not easily increase. Further, in the case of producing a graft-type polymer in which a plurality of different types of graft chains (Polymer A, B, ...) Are bonded to the main chain, it is necessary to prepare a plurality of types of corresponding macromonomers, which is complicated. It is neither efficient nor efficient.

（前記一般式（４）中、Ｒ₁〜Ｒ₄、Ｘ、及びＰｏｌｙｍｅｒは、前記一般式（１）中のＲ₁〜Ｒ₄、Ｘ、及びＰｏｌｙｍｅｒと同義である）

(In the general formula _{(4), R 1 ~R 4} , X, and Polymer, the general formula ₍₁₎ R 1 ~R ₄ in, X, and is synonymous with Polymer)

On the other hand, according to the above-mentioned method using a polymer containing a structural unit derived from the monomer represented by the general formula (2) (hereinafter, also referred to as “starting group polymer”), a plurality of types of macromonomers are previously prepared. It is not necessary to prepare it, and the desired graft-type polymer can be efficiently produced in one pot.

Specific examples of the monomer represented by the general formula (2) include the monomer represented by the following general formula (3).

（前記一般式（３）中、Ｒ₁及びＲ₂は、前記一般式（１）中のＲ₁及びＲ₂と同義である）

(In the general formula (3), R ₁ and R _2, the general formula (1) in the same meaning as that of R ₁ and R ₂₎

As the monomer represented by the general formula (3), a commercially available monomer or a synthesized monomer may be used. For example, a monomer represented by the general formula (3) is synthesized by reacting a (meth) acrylate having a hydroxyl group or a glycidyl group with 2-bromo-2-methylpropionic acid (2-bromoisobutyric acid). Can be done.

Further, it is represented by the general formula (2) by polymerizing a (meth) acrylate having a hydroxyl group or a glycidyl group and then reacting with a carboxylic acid having Y (chlorine atom, bromine atom, or iodine atom) or a derivative thereof. It is also possible to obtain a polymer (initiating group polymer) containing a structural unit derived from the monomer.

As the quaternary ammonium salt and the quaternary phosphonium salt, conventionally known compounds can be used. It is preferable that these quaternary salts are soluble in a polymerization solvent. These quaternary salts may be appropriately selected and used according to the type of monomer and polymerization solvent used.

Examples of the quaternary ammonium salt include tetramethylammonium salt, tetraethylammonium salt, tetrabutylammonium salt, methylimidazolium salt, and methylpyridinium salt. Examples of the quaternary phosphonium salt include tetrabutylphosphonium salt, tributylmethylphosphonium salt, triphenylmethylphosphonium salt and the like.

When the graft monomer is reacted with the initiating group polymer in the presence of an equimolar or more quaternary salt, all the initiating groups are halogen-exchanged to form a graft chain, and the desired graft-type polymer can be obtained. can. Further, in the case of producing a graft-type polymer in which a plurality of different types of graft chains (Polymer A, B, C, ...) Are bonded to the main chain, first, the number of moles is less than the equal number of the starting group polymer. The first-stage graft monomer is polymerized in the presence of a quaternary salt to form a graft chain (eg Polymer A). Then, the quaternary salt and the graft monomers of the second and subsequent stages are sequentially added, and the remaining starting groups are sequentially polymerized to form the graft chains of the second and subsequent stages (eg, Polymer B, C, ...). This makes it possible to obtain a graft-type polymer in which a plurality of different types of graft chains (Polymer A, B, C, ...) Are bonded to the main chain.

It is preferable to produce a graft type polymer by solution polymerization in which the polymer is polymerized in the presence of a polymerization solvent such as an organic solvent. As the polymerization solvent, a hydrocarbon solvent, a ketone solvent, an alcohol solvent, a glycol solvent, an amide solvent, an ester solvent, a urea solvent, an ionic liquid and the like can be used. Among them, it is preferable to use at least a part of a highly polar solvent capable of dissolving the quaternary salt and exchanging halogen. Such polymerization solvents include alcohol solvents such as methanol, ethanol and isopropanol; glycol solvents such as ethireglycol, propylene glycol, glycerin, diethylene glycol and propylene glycol monomethyl ether; dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc. Amide solvents such as 3-methoxy-N, N-dimethylpropanamide, 3-butoxy-N, N-dimethylpropanamide; sulfoxide solvents such as dimethylsulfoxide; ionicity such as imidazolium salts and quaternary ammonium salts Can be a liquid.

The amount of the polymerization solvent at the time of polymerization is preferably 30 to 80% by mass, more preferably 40 to 70% by mass, based on the whole polymerization reaction system. If the amount of the polymerization solvent is less than 30% by mass, the amount of solid content may be too large and the viscosity may become too high. On the other hand, if the amount of the polymerization solvent exceeds 80% by mass, the monomer concentration becomes too low, and the polymerization rate may decrease. The graft-type polymer may be used as it is (in a state of being dissolved in a polymerization solvent), or may be used by being precipitated in a poor solvent and taken out, and then dissolved in another solvent.

(solvent)
The coating composition of the present invention contains a solvent. As the solvent, for example, water can be used in addition to the organic solvent that can be used for the above-mentioned solution polymerization. Specific examples of the solvent include alcohol solvents such as methanol, ethanol and isopropanol; glycol solvents such as ethireglycol, propylene glycol, glycerin, diethylene glycol and propylene glycol monomethyl ether; dimethylformamide, dimethylacetamide, N-methylpyrrolidone, 3 Amide solvents such as -methoxy-N, N-dimethylpropanamide, 3-butoxy-N, N-dimethylpropanamide; ionic liquids such as imidazolium salt and quaternary ammonium salt; toluene, xylene, hexane, isoparaffin Carbohydrate-based solvents such as: Methyl ethyl ketone, Methyl isobutyl ketone and other ketone solvents; Ethyl acetate, propyl acetate, Butyl acetate, ethylene glycol dilauric acid, Trimethylol propanetriacetate and other ester solvents; propylene glycol monomethyl ether acetate, 3 Examples thereof include esterified products of glycol-based solvents such as −methoxy-3-methyl-1-butyl acetate; and the like.

(Crosslinking agent)
The coating composition of the present invention preferably further contains a cross-linking agent having two or more groups capable of reacting with reactive groups in the graft chain. By containing a cross-linking agent, a graft chain having a reactive group can be cross-linked to form a three-dimensional network structure. Thereby, the graft-type polymer can be cured to obtain a coating composition capable of forming a coating film having further improved mechanical properties and durability.

The cross-linking agent can be appropriately selected and used according to the type of reactive group in the graft chain. For example, when the reactive group is a carboxy group, it is preferable to use a melamine-based cross-linking agent such as a polyfunctional epoxy compound, a polyfunctional carbodiimide compound or methylol melamine, a polyfunctional oxazoline compound, or a polyvalent metal as the cross-linking agent. .. When the reactive group is a phosphoric acid group or a phosphoric acid ester group, it is preferable to use a compound having many hydroxyl groups as a cross-linking agent. When the reactive group is a hydroxyl group, it is preferable to use a polyfunctional isocyanate compound, a blocked isocyanate thereof, an acid anhydride or the like as a cross-linking agent. When the reactive group is a glycidyl group, it is preferable to use a polyfunctional carboxy group-containing compound, a polyamine, an acid anhydride or the like as a cross-linking agent. When the reactive group is an isocyanate group or a blocked isocyanate group, it is preferable to use a polyol, a polyamine, a polycarboxylic acid compound or the like as a cross-linking agent. When the reactive group is an alkoxysilyl group, it is preferable to use water, a polyalkoxysilyl group compound, or the like as a cross-linking agent. When the reactive group is a (meth) acryloyl group, it is preferable to use a polyunsaturated compound or the like as a cross-linking agent.

The amount of the graft-type polymer or the cross-linking agent in the coating composition is not particularly limited, and may be appropriately set according to the properties of the coating film to be formed and the like. The amount of the graft-type polymer in the coating composition is generally 5 to 50% by mass, preferably 10 to 30% by mass. Further, the amount of the cross-linking agent in the coating composition is adjusted by the amount of functional groups contained in the graft-type polymer and the molecular weight of the cross-linking agent to be added, so it cannot be said unconditionally, but in general, the graft-type polymer. It may be 0.5 to 100 parts with respect to 100 parts, preferably 1 to 50 parts.

The coating composition may be a composition for forming a substantially transparent (clear) coating film, and various additives may be blended if necessary. For example, colorants such as dyes and pigments, pigment dispersants, defoaming agents, leveling agents, preservatives, UV absorbers, light stabilizers, thickeners, photoinitiators, photoacid generators, photobase generators, Photosensitizers, antibacterial agents, antifungal agents, antifogging agents, water repellents, antistatic agents, conductive agents, reinforcing materials, fibrous substances, other polymer components and the like can be blended.

The coating composition of the present invention can be used, for example, as a gravure ink, an offset ink, an inkjet ink, an ultraviolet curable ink, an electron beam curable ink, an oil-based paint for automobiles and buildings, and a water-based paint. Further, the coating composition of the present invention is a material in various fields such as plastics, color filter materials, energy-related materials, mechanical parts-related materials, medical devices, medical materials, drug-related materials, healthcare, battery materials, and organic EL materials. It can be used as a material for forming a coating film (coating film).

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples. In addition, "part" and "%" in Examples and Comparative Examples are based on mass unless otherwise specified.

<Synthesis of polymerization initiator group-containing polymer>
(Synthesis Example 1)
561 parts of 3-methoxy-N, N-dimethylpropanamide (MDPA), 1 part of iodine, 2,2'-azobis (4-) in a reactor equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen introduction tube. Methoxy-2,4-dimethylvaleronitrile) (trade name "V-70", manufactured by Wako Pure Chemical Industries, Ltd. (V-70)) 3.7 parts, 2-hydroxyethyl methacrylate (HEMA) 208 parts, and N- 0.113 parts of iodosuccinimide (NIS) was added. A polymerization solution was obtained by polymerizing at 65 ° C. for 7 hours while blowing nitrogen. The polymerization rate was about 100%. The polystyrene-equivalent number average molecular weight (Mn) of the polymer in the polymerization solution as measured using a GPC apparatus (solvent: dimethylformamide (DMF)) equipped with a visible light detector (RI) is 20,000. The molecular weight distribution (dispersity PDI) was 1.12.

189.5 parts of pyridine was added to the obtained polymerization solution, and the mixture was cooled to 5 ° C. in an ice bath. 459.8 parts of 2-bromoisobutyric acid bromide was placed in the dropping funnel, and the mixture was added dropwise over 3 hours so as not to exceed 10 ° C. After leaving it at that temperature for 2 hours, it was heated to 45 ° C. and reacted for 1 hour. After cooling to room temperature, 561 parts of methanol was added and stirred. 5,000 parts of methanol was placed in a separate container, and the polymerization solution was gradually added while stirring with a disper to precipitate a soft polymer. The precipitated polymer was separated, added to a large amount of water with stirring with a disper, and washed. After filtration and washing with water, the polymer (1) (initiator group polymer (1)), which is a white powdery solid, is dried using a blower dryer at 50 ° C. until the volatile matter disappears. Obtained. The starting group polymer (1) measured using a GPC apparatus equipped with an RI detector (solvent: tetrahydrofuran (THF)) had a Mn of 28,000 and a PDI of 1.31.

<Manufacturing of coating composition (1)>
(Example 1)
In the same reactor as the reactor used in Synthesis Example 1, 200 parts of MDPA, 200 parts of methyl methacrylate (MMA), 11 parts of the initiating group polymer (1), 11.8 parts of tetrabutylammonium iodide (TBAI), and The NIS 0.3 part was put. Polymerization at 75 ° C. for 8 hours gave a highly viscous liquid. The polymerization rate measured by sampling a small amount was 86%. The Mn of the polymer in the solution was 134,000, and the PDI was 1.40. After cooling the obtained solution to room temperature, it was gradually added to 5,000 parts of methanol to precipitate a polymer. The precipitated polymer was filtered and then dried at 80 ° C. for 12 hours. As a result, a starting group polymer (2), which is a graft polymer having a starting group, was obtained.

In a similar reactor, 200 parts of MDPA, 25 parts of MMA, 25 parts of methacryloyloxypropyl tetraethoxysilane (MPTES), 100 parts of starting group polymer (2), 11.8 parts of TBAI, and 0.3 parts of NIS were placed. Polymerization at 75 ° C. for 8 hours gave a liquid containing the polymer. The polymerization rate measured by sampling a small amount was 91%, the Mn of the polymer was 208,000, and the PDI was 1.43. The obtained polymer is a graft chain in which Polymer A in the general formula (1-A) is composed of a structural unit derived from MMA, and Polymer B in the general formula (1-B) is derived from MMA and MPTES. It is a graft-type polymer that is a graft chain consisting of units. The obtained polymer is designated as GP-1 polymer. A liquid containing the GP-1 polymer was gradually added to methanol to precipitate the GP-1 polymer to obtain a white paste (solid content 65.2%). Propylene glycol monomethyl ether acetate (PGMAc) was added to the obtained white paste to dissolve it, and then the paste was heated to 80 ° C. to remove methanol. PGMAc was added to adjust the solid content to obtain a solution of GP-1 polymer having a solid content of 10%. The obtained solution of GP-1 polymer was used as the coating composition of Example 1.

(Comparative Example 1)
100 parts of PGMAc was placed in a reaction device similar to the reaction device used in Synthesis Example 1, heated to 70 ° C., and nitrogen was blown into it. 82 parts of MMA, 8 parts of MPTES, and 1 part of azobisisobutyronitrile (AIBN) were placed in a separate container, and nitrogen was blown into the container to prepare a monomer solution. The prepared monomer solution was added dropwise to the reactor over 3 hours and polymerized for 7 hours to obtain a highly viscous polymer solution. The polymerization rate measured by sampling a small amount was about 100%. The Mn of the polymer in the solution was 65,000, and the PDI was 3.12. The obtained polymer is designated as an RP-1 polymer. PGMAc was added to the liquid containing the RP-1 polymer to adjust the solid content, and a solution of the RP-1 polymer having a solid content of 10% was obtained. The obtained solution of RP-1 polymer was used as the coating composition of Comparative Example 1. The RP-1 polymer is a linear random copolymer.

<Evaluation of coating composition>
After degreasing, a silicon plate whose surface was activated with UV ozone was prepared. Using a spin coater, the coating composition of Example 1 and the coating composition of Comparative Example 1 were respectively applied to the surface of the prepared silicon plate under the conditions of 2,000 rpm and 30 seconds. Then, it was baked at 90 ° C. for 1 minute and 180 ° C. for 30 minutes to form a coating film. The film thicknesses of the coating film measured by ellipsometry were 612 nm (Example 1) and 423 nm (Example 2), respectively.

After immersing the silicon plate on which the coating film was formed in toluene for 24 hours, the appearance was confirmed. As a result, it was found that the coating film formed by the coating composition of Example 1 was not peeled off and was in close contact with the silicon plate. On the other hand, the coating film formed by the coating composition of Comparative Example 1 was partially peeled off.

In addition, a reciprocating sliding friction test was performed using a Heidon friction tester type 14 to rub the surface of the coating film under the conditions of a load of 50 g and an amplitude of 3 cm. As a result, it was found that the friction coefficient of the coating film surface formed by the coating composition of Example 1 was 0.002, and the film thickness of the coating film after the test was 605 nm. On the other hand, the friction coefficient of the surface of the coating film formed by the coating composition of Comparative Example 1 was 0.018, and it was found that the surface of the coating film after the test had irregularities and the film thickness was also reduced. .. From the above, it can be seen that by using the coating composition of the example, it is possible to form a coating film having excellent scratch resistance and adhesion to the substrate and having a surface having a small friction coefficient.

<Manufacturing of coating composition (2)>
(Example 2)
In a reactor similar to the one used in Synthesis Example 1, 150 parts of propylene glycol monopropyl ether (PPG), 2.8 parts of the initiating group polymer (1), and 2.6 parts of tetrabutylammonium bromide (TBAB) were added. I put it in. After heating to 85 ° C., 80 parts of MMA was added and polymerized for 5 hours to obtain a solution containing the polymer. The polymerization rate measured by sampling a small amount was 68.4%. The Mn of the polymer in the solution was 90,000 and the PDI was 2.55.

Then, 1 part of TBAB, 15 parts of benzyl methacrylate (BzMA), and 5 parts of HEMA were added and polymerized for 6 hours, and then 150 parts of PGMAc was added to obtain a liquid containing a polymer having a solid content of 40.8%. The polymerization rate calculated by quantifying the residual monomer by gas chromatography was about 100%. The Mn of the obtained polymer was 120,000 and the PDI was 2.64, which were monomodal. The Mn of the polymer measured using a GPC apparatus equipped with an ultraviolet absorption detector (measurement wavelength: 254 nm) was 122,000, and the PDI was 2.43. The obtained polymer is a graft chain in which Polymer A in the general formula (1-A) is composed of a structural unit derived from MMA, and Polymer B in the general formula (1-B) is derived from BzMA and HEMA. It is a graft-type polymer that is a graft chain consisting of units. The obtained polymer is designated as GP-2 polymer. A liquid containing the GP-2 polymer was gradually added to methanol, and the resulting precipitate was filtered and then dried to obtain a GP-2 polymer. The hydroxyl value of the GP-2 polymer measured according to the phthalic acid method of JIS K 1557-1: 2007 was 19.9 mgKOH / g.

49 parts of liquid containing GP-2 polymer, 46.8 parts of PGMAc, and 4.2 parts of blocked isocyanate (trade name "Duranate SBB-70", manufactured by Asahi Kasei Corporation, solid content 70%, NCO 10.1%) are mixed. The coating composition of Example 2 was prepared. The prepared coating composition was applied to a polyimide film by screen printing and then heat-treated at 80 ° C. for 30 minutes and at 150 ° C. for 60 minutes to form a coating film having a film thickness of 5 μm. The polyimide film on which the coating film was formed was immersed in toluene for 24 hours, and then the appearance was observed. As a result, it was found that no swelling or cracking occurred, and the coating film in a good condition was maintained.

(Example 3)
300 parts of PPG, 5.6 parts of the initiating group polymer (1), and 5.2 parts of TBAB were placed in a reaction device similar to the reaction device used in Synthesis Example 1. After heating to 85 ° C., 160 parts of MMA was added and polymerized for 5 hours to obtain a liquid containing a polymer. The polymerization rate measured by sampling a small amount was 86%. The Mn of the polymer in the liquid was 135,000, and the PDI was 2.30.

Next, 2 parts of TBAB, 30 parts of MMA, and 2- (0- (1'-methylpropylideneamino) carboxyamino) ethyl methacrylate (trade name "Karenzu MOI-BM", manufactured by Showa Denko KK (MOI-BM)) 10 After adding the parts and polymerizing for 5 hours, 300 parts of PGMAc was added to obtain a liquid containing a polymer having a solid content of 26.0%. The polymerization rate calculated by quantifying the residual monomer by gas chromatography was about 100%. The Mn of the obtained polymer was 156,000, and the PDI was 2.44. In the obtained polymer, Polymer A in the general formula (1-A) is a graft chain composed of structural units derived from MMA, and Polymer B in the general formula (1-B) is derived from MMA and MOI-BM. It is a graft-type polymer that is a graft chain composed of constituent units. The obtained polymer is designated as GP-3 polymer. The amount of isocyanate (NCO) of the GP-3 polymer was 0.2 mmol / g.

76.9 parts of a solution containing GP-3 polymer, 19.1 parts of PGMAc, and 4 parts of polycarbonate diol (trade name "Duranol T5652", manufactured by Asahi Kasei Corporation, solid content 100%, hydroxyl value 56.4 mgKOH / g) are mixed. Then, the coating composition of Example 3 was prepared. The prepared coating composition was applied to a polyimide film by screen printing and then heat-treated at 80 ° C. for 30 minutes and at 150 ° C. for 60 minutes to form a coating film having a film thickness of 5 μm. The polyimide film on which the coating film was formed was immersed in N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium bis (trifluoromethanesulfonyl) imide for 24 hours, and then the appearance was observed. As a result, it was found that no peeling occurred and the coating film in a good condition was maintained. Further, the above-mentioned reciprocating sliding friction test was performed on the polyimide film on which the coating film was formed. As a result, it was found that the coefficient of friction on the surface of the coating film was 0.009.

Further, when the GP-2 polymer (graft type polymer having a hydroxyl group) produced in Example 2 was used instead of the polycarbonate diol (Duranol T5652), a coating film having the same performance and friction coefficient could be formed. rice field.

(Example 4)
In a reactor similar to the reactor used in Synthesis Example 1, 150 parts of 3-butoxy-N, N-dimethylpropanamide (BDPA), 2.8 parts of the initiating group polymer (1), and 2.6 parts of TBAB were placed. rice field. After heating to 85 ° C., 60 parts of lauryl methacrylate (LMA) was added and polymerized for 5 hours to obtain a solution containing the polymer. The polymerization rate measured by sampling a small amount was 77.3%. The Mn of the polymer in the solution was 85,800, and the PDI was 2.24.

Next, 2 parts of TBAB, 30.0 parts of BzMA, 5 parts of MOI-BM, and 5 parts of HEMA were added and polymerized for 4 hours, and then 250 parts of PGMAc was added to obtain a liquid containing a polymer having a solid content of 20.5%. .. The polymerization rate calculated by quantifying the residual monomer by gas chromatography was about 100%. The Mn of the obtained polymer was 105,200, and the PDI was 2.85. In the obtained polymer, Polymer A in the general formula (1-A) is a graft chain composed of a structural unit derived from LMA, and Polymer B in the general formula (1-B) is BzMA, MOI-BM, and It is a graft-type polymer that is a graft chain composed of structural units derived from HEMA. The obtained polymer is designated as GP-4 polymer.

PGMAc was added to the obtained liquid containing the GP-4 polymer and diluted to prepare the coating composition (solid content 10%) of Example 4. Using a spin coater, the coating composition of Example 4 was applied to the surface of the glass plate under the conditions of 2,000 rpm and 30 seconds. Then, it was treated at 90 ° C. for 30 seconds and at 180 ° C. for 20 minutes to be cured to form a coating film having a film thickness of 1.1 μm. The glass plate on which the coating film was formed was immersed in pentaerythritol tetra2-ethylhexanoate (lubricating oil) for 24 hours, and then the appearance was observed. As a result, it was found that the formed coating film was not peeled off and was in close contact with the glass plate. As described above, it can be seen that by using the coating composition of Examples, it is possible to form a coating film showing good resistance to lubricating oil.

(Example 5)
300 parts of ethylene glycol monobutyl ether, 11.2 parts of the initiating group polymer (1), and 5.2 parts of TBAB were placed in a reaction device similar to the reaction device used in Example 1. After heating to 85 ° C., 100 parts of BzMA was added and polymerized for 5 hours to obtain a liquid containing the polymer. The polymerization rate measured by sampling a small amount was 77.3%. The Mn of the polymer in the liquid was 75,800, and the PDI was 2.24.

Then, 2 parts of TBAB, 60 parts of BzMA, and 40.0 parts of methacrylic acid (MA) were added and polymerized for 8 hours to obtain a highly viscous solution containing a polymer. The polymerization rate calculated by quantifying the residual monomer by gas chromatography was about 100%. The Mn of the obtained polymer was 105,600, and the PDI was 2.85. The obtained polymer is a graft chain in which Polymer A in the general formula (1-A) is derived from BzMA, and Polymer B in the general formula (1-B) is derived from BzMA and MA. It is a graft-type polymer that is a graft chain consisting of units. The obtained polymer is designated as GP-5 polymer.

A part of the solution containing the GP-5 polymer was added to methanol, and the resulting precipitate was dried to obtain a GP-5 polymer. 0.1 g of the obtained GP-5 polymer and 50 mL of a toluene / ethanol (= 1/1) mixed solvent were placed in a 100 mL conical beaker to dissolve the GP-5 polymer. The acid value of the GP-5 polymer measured by titrating with a 0.1N potassium hydroxide ethanol solution using phenolphthalein as a titration indicator was 126.1 mgKOH / g.

Further, 30 parts of a 28% aqueous ammonia solution and 270 parts of ion-exchanged water were mixed to prepare ammonia water. The liquid containing the GP-5 polymer was heated to 70 ° C., and aqueous ammonia was gradually added. Then, 200 parts of ion-exchanged water was added to obtain a cloudy, low-viscosity emulsion. The solid content of the obtained emulsion was 20.6%. 48.5 parts of the obtained emulsion and 1.87 parts of a polycarbodiimide-based cross-linking agent (trade name "Carbodilite E-02", manufactured by Nisshinbo, Inc., solid content 40.0%) are mixed to form the coating of Example 5. The composition was prepared. The coating composition prepared using a bar coater was applied to an aluminum plate and then heat-treated at 150 ° C. for 15 minutes to be cured to form a coating film. After immersing the aluminum plate on which the coating film was formed in water for 24 hours, the appearance was observed. As a result, it was found that no peeling or whitening occurred, and a coating film having excellent water resistance was formed.

Further, instead of the polycarbodiimide-based cross-linking agent (carbodilite E-02), a water-soluble polyepoxy-based cross-linking agent (trade name "Denacol EX-411", manufactured by Nagase Chemtech Co., Ltd., 100% solid content) was used. It was possible to form a coating film showing the same water resistance.

(Example 6)
In a reactor similar to the reactor used in Synthesis Example 1, 150 parts of MDPA, 2.8 parts of the initiating group polymer (1), and 2.6 parts of TBAB were placed. After heating to 85 ° C., 50 parts of MMA and 40 parts of HEMA were added and polymerized for 10 hours to obtain a solution containing the polymer. The polymerization rate measured by sampling a small amount was about 100%. The Mn of the polymer in the solution was 178,000, and the PDI was 1.74.

Next, 10 parts of 2-acryloyloxyethyl isocyanate (trade name "Karenzu AOI", manufactured by Showa Denko KK (Karenzu AOI)) and 1 part of a 10% MPDA solution of tin dioctanoate were added, and the mixture was heated at 85 ° C. for 5 hours. A liquid containing the polymer was obtained. Analysis was performed using an infrared spectrophotometer, and it was confirmed that the peak (isocyanate group) of ^{2,250 cm -1 disappeared and a urethane bond was formed.} PGMAc was added and diluted to obtain a liquid containing a polymer having a solid content of 15%. The obtained polymer had a Mn of 198,000 and a PDI of 1.59. In the obtained polymer, Polymer A in the general formula (1-A) is a graft chain composed of structural units derived from MMA and HEMA, and Polymer B in the general formula (1-B) is derived from Karenz AOI. It is a graft-type polymer that is a graft chain composed of constituent units. The obtained polymer is designated as GP-6 polymer.

100 parts of the liquid containing the GP-6 polymer and 0.1 part of the 1-hydroxycyclohexylphenyl ketone were mixed to prepare the coating composition of Example 6. The coating composition prepared using a knife coater was applied to a film made of polyethylene terephthalate. Using an ultraviolet irradiation device equipped with a high-pressure mercury lamp of 120 W / cm, ^{after irradiating with ultraviolet rays under the condition of irradiation light amount of 0.8 J / cm 2} in a nitrogen atmosphere, put it in an oven and heat it at 60 ° C for 10 minutes to apply it. A film was formed. Even when the film on which the coating film was formed was bent, the coating film did not crack or whiten, and was maintained in a good state.

The coating composition of the present invention has low friction and abrasion resistance on the surfaces of home appliances, automobiles, electronic device members, battery members, display members, containers, building materials, packaging materials, medical members, and energy-related members, for example. It is useful as a material for forming a coating film having excellent water resistance, adhesion, electrical characteristics, heat resistance, chemical resistance, abrasion resistance, and the like.

2,12: Main chain 4: Graft chain 10,20: Graft type polymer

Claims (3)

A coating composition containing a solvent and a polymer.
The polymer is a graft-type polymer containing 80% by mass or more of a structural unit represented by the following general formula (1).
A coating composition of the polymer having a polystyrene-equivalent number average molecular weight of 10,000 or more and 1,000,000 or less as measured by gel permeation chromatography.

(In the general formula (1), R ₁ represents a hydrogen atom or a methyl group, X represents O or NH, R ₂ represents an arbitrary organic group, and R ₃ and R ₄ are independent of each other. Is a hydrogen atom, an alkyl group, an aryl group, or an acyl group, and the _{carbon atom to which R 3 and R 4} are bonded is a tertiary carbon atom or a quaternary carbon atom, and n is an arbitrary repetition. Indicating a number, Polymer is a structural unit derived from at least one graft monomer selected from the group consisting of (meth) acrylic acid-based monomer, (meth) acrylamide-based monomer, aromatic vinyl-based monomer, and (meth) acrylonitrile. shows a graft chain containing the graft monomer, a carboxy group, a phosphoric acid group, a phosphoric acid ester group, a hydroxyl group, glycidyl group, isocyanate group, blocked isocyanate group, one of the alkoxysilyl group, and (meth) acryloyl groups Has a reactive group ) A coating composition containing a solvent and a polymer.
The polymer is a graft-type polymer containing 80% by mass or more of a structural unit represented by the following general formula (1).
The polystyrene-equivalent number average molecular weight of the polymer measured by gel permeation chromatography is 10,000 or more and 1,000,000 or less.
The polymer contains two or more structural units having different Polymers in the following general formula (1).
A coating composition in which the two or more structural units include a structural unit A represented by the following general formula (1-A) and a structural unit B represented by the following general formula (1-B).

(In the general formula (1), R ₁ represents a hydrogen atom or a methyl group, X represents O or NH, R ₂ represents an arbitrary organic group, and R ₃ and R ₄ are independent of each other. Is a hydrogen atom, an alkyl group, an aryl group, or an acyl group, and the _{carbon atom to which R 3 and R 4} are bonded is a tertiary carbon atom or a quaternary carbon atom, and n is an arbitrary repetition. Indicating a number, Polymer is a structural unit derived from at least one graft monomer selected from the group consisting of (meth) acrylic acid-based monomers, (meth) acrylamide-based monomers, aromatic vinyl-based monomers, and (meth) acrylonitrile. Indicates a graft chain containing

(In the general formula _{(1-A), R 1} ~R 4, X, and n, _R 1 _{to R} 4, X in the general formula (1), and has the same meaning as n, Polymer A is Indicates a graft chain consisting of a structural unit derived from a first graft monomer having no reactive group)

(In the general formula _{(1-B), R 1} ~R 4, X, and n, _R 1 _{to R} 4, X in the general formula (1), and has the same meaning as n, Polymer B is A second graft monomer having a reactive group of any one of a carboxy group, a phosphoric acid group, a phosphoric acid ester group, a hydroxyl group, a glycidyl group, an isocyanate group, a blocked isocyanate group, an alkoxysilyl group, and a (meth) acryloyl group. Indicates a graft chain containing the structural unit from which it is derived) The coating composition according to claim 1 or 2 , further comprising a cross-linking agent having two or more groups capable of reacting with the reactive group.

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