WO2017094251A1

WO2017094251A1 - Method for producing soluble cross-linked polymer

Info

Publication number: WO2017094251A1
Application number: PCT/JP2016/004985
Authority: WO
Inventors: 顕夫田村
Original assignee: 富士フイルム株式会社
Priority date: 2015-12-03
Filing date: 2016-11-28
Publication date: 2017-06-08
Also published as: JPWO2017094251A1

Abstract

[Problem] To provide a method for producing a soluble cross-linked polymer that is highly compatible with coating compositions, and that satisfactorily reduces pimple defects on a coating film when used as an additive. [Solution] A monomer A having two or more radical polymerizable double bonds per molecule is polymerized in a first organic solvent in the presence of a polymerization initiator B in an amount of 5 mol% to 200 mol% per mole of the monomer A,at a temperature that is at least 20˚C higher than the 10-hour half-life temperature of the polymerization initiator B, without refluxing.

Description

Method for producing soluble cross-linked polymer

The present invention relates to a method for producing a soluble cross-linked polymer.

In an image display device such as a liquid crystal display device (LCD), a hard coat film having a hard coat layer is provided on a support in order to prevent damage to the display surface. Many of such films are produced by laminating coating films. A leveling agent such as a fluorine-containing polymer is usually added to the hard coat layer composition in order to enhance the homogeneity of the coating film of the hard coat layer itself. However, the surface of the hard coat layer is hydrophobized by the hydrophobicity of the leveling agent, and the recoatability (lamination property) is lowered. Therefore, a specific fluorosurfactant or a fluorine-containing polymer is added for the purpose of improving the uniform coatability on the substrate during coating and improving the recoatability after coating. However, even a coating composition containing them does not have sufficient uniformity and recoatability of the coating film itself.

In recent years, so-called three-dimensional dendritic polymers (also called dendritic polymers) such as hyperbranched polymers and dendrimers have attracted attention. Such highly branched polymers have properties different from ordinary linear polymers, such as low melt viscosity, low melt viscosity, and high solubility, and are expected to be applied as surfactants and surface modifiers. Has been. In that case, the properties of the polymer itself and the properties of the coating film surface formed by adding the polymer and the interface of the laminated film when the coating film is laminated are also important.

As a method for producing a hyperbranched polymer, there is a method of radical polymerization of a system containing a vinyl monomer, but it is difficult to control the molecular weight, and an insoluble and infusible polymer may be produced. Therefore, an initiator-incorporated radical polymerization in which a monomer is polymerized in the presence of a high concentration radical polymerization initiator has been proposed.

For example, Patent Document 1 discloses that a monomer A having two or more radically polymerizable double bonds in the molecule is a polymerization initiator in an amount of 5 mol% to 200 mol% with respect to 1 mol of the monomer A in an organic solvent. A method of polymerizing under reflux at a temperature 20 ° C. or more higher than the 10-hour half-life temperature of the polymerization initiator B in the presence of B is disclosed. It is described that according to this production method, the molecular weight can be controlled by a simple method, and the weight average molecular weight can be controlled within a range that can be dissolved in a solvent.

Patent Document 2 discloses a monomer (A) having one radical polymerizable unsaturated double bond and a monomer (B) having two or more radical polymerizable unsaturated double bonds (A ) And (B), a method of polymerizing in the presence of 15 to 170 mol% of a polymerization initiator (C) is disclosed. According to this production method, it is described that a three-dimensional polymer having a volume average particle diameter of 1 nm to 300 nm can be easily obtained.

Japanese Patent No. 5773159 Japanese Patent No. 4009700

The present inventor, as an example, uses a hyperbranched polymer obtained by the method described in Patent Document 1 as a surface modification to a coating composition for producing a hard coat layer used in an image display device such as a liquid crystal display device. When it was added as an agent and the composition was used as a coating film, a plurality of minute bright spot-like defects, so-called lumpy defects, caused by impurities were generated on the surface of the cured film. Thus, when a highly branched polymer is added to the coating composition as a surface modifier or the like, it is required to suppress the generation of impurities at a higher level (mainly below the detection limit).
The present invention has been made in view of the above circumstances, and when a highly branched polymer is used as an additive for a coating composition, an insoluble component is hardly generated, the compatibility with the coating composition is good, and It is an object of the present invention to provide a method for producing a soluble cross-linked polymer in which, when the composition is used as a coating film, the uneven defects are satisfactorily reduced.

The present inventors thought that the above-mentioned lumpy defects were caused by undesired by-products, mainly impurity components below the detection limit. And it was speculated that the cause of the generation of impurities may be temperature control in the polymerization reaction under reflux. That is, when the monomer solution is added dropwise at reflux, the temperature of the mixed system may become constant at a temperature that is not the temperature at which the target polymer is formed, and as a result, a higher molecular weight polymer is formed when the temperature is lowered. As the temperature increases, a low molecular weight polymer is produced. Therefore, the present inventor found that the non-reflux method was used instead of the recirculation method which was thought to have good temperature control. The present invention has been reached.

In the method for producing a soluble cross-linked polymer of the present invention, the monomer A having two or more radical polymerizable double bonds in the molecule is added in an amount of 5 mol% to 200 mol with respect to 1 mol of the monomer A in the first organic solvent. In the presence of a polymerization initiator B in an amount of not more than%, the polymerization is carried out under non-refluxing at a temperature 20 ° C. or more higher than the 10-hour half-life temperature of the polymerization initiator B.

The monomer A may be polymerized by dropping a solution containing the monomer A, the polymerization initiator B and the second organic solvent into the first organic solvent.

The solution may further contain a monomer C having one radical polymerizable double bond in the molecule, and the monomer A and the monomer C are polymerized by dropping this solution into the first organic solvent. Also good.

The weight average molecular weight of the soluble cross-linked polymer is preferably 1,000 to 300,000 in terms of polystyrene by gel permeation chromatography.

The weight average molecular weight of the soluble cross-linked polymer is preferably 1,000 to 50,000 in terms of polystyrene by gel permeation chromatography.

In the method for producing a soluble cross-linked polymer of the present invention, the monomer A having two or more radical polymerizable double bonds in the molecule is added in an amount of 5 mol% to 200 mol with respect to 1 mol of the monomer A in the first organic solvent. Polymerization is carried out in a non-reflux state at a temperature 20 ° C. or more higher than the 10-hour half-life temperature of the polymerization initiator B in the presence of a polymerization initiator B in an amount of% or less. According to this method, the generation of impurities can be suppressed satisfactorily. For this reason, when the obtained polymer is used as an additive in a coating composition, it is possible to obtain a film having good compatibility with the coating composition and having well-formed defects. This is presumed to be because the production of a trace amount of impurities could be suppressed by setting the non-reflux to polymerize at a temperature lower than the boiling point.

Hereinafter, a method for producing the soluble cross-linked polymer of the present invention will be described. The following description may be made based on representative embodiments of the present invention, but the present invention is not limited to such embodiments. In this specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

[Method for producing soluble cross-linked polymer]
In the method for producing a soluble cross-linked polymer of the present invention, the monomer A having two or more radical polymerizable double bonds in the molecule is added in an amount of 5 mol% or more to 200 mol% with respect to 1 mol of the monomer A in the first organic solvent. the presence of mol% of the amount of the polymerization initiator B, 10-hour half-life temperature of the polymerization initiator B (hereinafter, may be described as T _10.) from 20 ° C. or higher high temperature (hereinafter, the polymerization temperature T And may be polymerized under non-reflux.
It is considered that the production of a trace amount of impurities was suppressed by polymerization under non-reflux, and as a result, when the hyperbranched polymer produced by the production method of the present invention was used as an additive for a coating composition, Since the compatibility with the coating composition is good, it is possible to obtain a good film surface shape with suppressed irregularities.
First, the material used for the manufacturing method of a soluble bridge | crosslinking type polymer is demonstrated.

(Monomer A)
Monomer A is a polyfunctional monomer having two or more radically polymerizable double bonds in the molecule.
Examples of the polyfunctional monomer used for the monomer A include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol (meth) acrylate, and ethylene glycol di (meth) acrylate. ) Acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, 3-methylpentanediol di (meth) acrylate, diethylene glycol bis β- (meth) acryloyloxy Propinate, trimethylolethane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meta) Acrylate, tri (2-hydroxyethyl) isocyanate di (meth) acrylate, pentaerythritol tetra (meth) acrylate, 2,3-bis (meth) acryloyloxyethyloxymethyl [2.2.1] heptane, poly 1,2 Butadiene di (meth) acrylate, 1,2-bis (meth) acryloyloxymethylhexane, nonaethylene glycol di (meth) acrylate, tetradecane ethylene glycol di (meth) acrylate, 10-decanediol (meth) acrylate, 3, 8-bis (meth) acryloyloxymethyltricyclo [5.2.10] decane, 2,2-bis (4- (meth) acryloyloxydiethoxyphenyl) propane, 1,4-bis ((meth) acryloyloxy Methyl) cyclohexane, Hydroxypivalate ester neopentyl glycol di (meth) acrylate, EO (ethylene oxide) modified trimethylolpropane tri (meth) acrylate, PO (propylene oxide) modified trimethylolpropane tri (meth) acrylate, EO modified triphosphate (meta) ) Acrylate, 1,2,3-chlorohexane tetramethacrylate, polyurethane polyacrylate, polyester polyacrylate, caprolactone-modified tris (acryloxyethyl) isocyanurate, and the like.

Monomer A may be a polyfunctional acrylate compound having three or more (meth) acryloyl groups in the molecule. Specific examples include KAYARAD DPHA, DPHA-2C, PET-30, TMPTA, TPA-320, TPA-330, RP-1040, T-1420, and D from Nippon Kayaku Co., Ltd. -310, DPCA-20, DPCA-30, DPCA-60, GPO-303, Osaka Organic Chemical Industry Co., Ltd. V # 400, V # 36095D, etc. Can be mentioned. Purple light UV-1400B, UV-1700B, UV-6300B, UV-7550B, UV-7600B, UV-7605B, UV-7610B, UV-7620EA, UV-7630B, UV-7630B, UV-7640B UV-6630B, UV-7000B, UV-7510B, UV-7461TE, UV-3000B, UV-3200B, UV-3210EA, UV-3310EA, UV-3310EA, UV-3310B, UV-3500BA UV-3520TL, UV-3700B, UV-6100B, UV-6640B, UV-2000B, UV-2010B, UV-2250EA, UV-2250EA (manufactured by Nippon Synthetic Chemical Co., Ltd.), UL-503LN (manufactured by Kyoeisha Chemical Co., Ltd.), Unidic 17-80 17-813, V-4030, V-4000BA (Dainippon Ink Chemical Co., Ltd.), EB-1290K, EB-220, EB-5129, EB-1830, EB-4358 (Daicel UCB ( Ltd.), High Corp AU-2010, AU-2020 (manufactured by Tokushi Co., Ltd.), Aronix M-1960 (manufactured by Toagosei Co., Ltd.), Art Resin UN-3320HA, UN-3320HC, UN-3320HS, UN Trifunctional urethane acrylate compounds such as -904, HDP-4T, etc., Aronix M-8100, M-8030, M-9050 (manufactured by Toagosei Co., Ltd., KBM-8307 (manufactured by Daicel Cytec Co., Ltd.)) The above polyester compounds and the like can also be suitably used.
Only one type of monomer A may be used from the above, or a mixture of two or more types may be used.

(Polymerization initiator B)
In the method for producing a soluble crosslinked polymer of the present invention, the polymerization initiator B is present in an amount of 5 mol% or more and 200 mol% or less with respect to 1 mol of the monomer A. By setting the amount of the polymerization initiator B to 5 mol% or more and 200 mol% or less, it is possible to produce a soluble cross-linked polymer with good molecular weight control. And when the obtained polymer is used as an additive of a coating composition, what is called a dent-like defect can be reduced favorably.
Examples of the polymerization initiator B include an azo polymerization initiator, a peroxide polymerization initiator, a redox polymerization initiator using a peroxide polymerization initiator and a reducing agent in combination, and a mixture of two or more of the above.

As the azo polymerization initiator, an oil-soluble azo polymerization initiator is preferable. Specifically, 2,2′-azobisisobutyronitrile, 1,1′-azobiscyclohexane 1-carbonitrile, 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, 2 2,2′-azobis-2,4-dimethylvaleronitrile, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2′-azobis (2-methylbutyronitrile), 2 2,2′-azobis (2,4,4-trimethylpentane), dimethyl 2,2′-azobisisobutyrate, 1,1′-azobis (1-acetoxy-1-phenylethane) and the like.
Of these, 2,2′-azobisisobutyronitrile and dimethyl 2,2′-azobisisobutyrate are particularly preferable.

As the peroxide polymerization initiator, the following oil-soluble peroxide polymerization initiators are preferably used.
(1) ketone peroxide (methyl ethyl peroxide, methyl isobutyl peroxide, acetylacetone peroxide, cyclohexanone peroxide, etc.),
(2) Hydroperoxide (1,1,3,3-tetramethylbutyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, etc.),
(3) Diacyl peroxide (isobutyryl peroxide, bis-3,5,5-trimethylhexanoyl peroxide, lauroyl peroxide, benzoyl peroxide, etc.),
(4) Dialkyl peroxide (dicumyl peroxide, 2,5-dimethyl-2,5-di- (t-butylperoxyhexane), 1,3-bis (t-butylperoxyisopropyl) benzene, t-butylcumi Ruperoxide, di-t-butyl peroxide,
2,5-dimethyl-2,5di- (t-butylperoxy) hexene, tris (t-butylperoxy) triazine, etc.),
(5) Peroxyketal (1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexyl peroxide, 1,1-di-t-peroxycyclohexane, 2,2-di (t-) butyl Peroxy) butane, 4,4-di-t-butylperoxyvaleric acid-n-butyl ester, 2,2-bis (4,4-di-t-butylperoxycyclohexyl) propane, etc.),
(6) Alkyl perester (1,1,3,3-tetramethylbutylperoxyneodecanoate, α-cumylperoxyneodecanoate, t-butylperoxyneodecanoate, t-butylperoxyneopentanoate Ate, t-butyl peroxypivalate, t-butyl peroxypivalate, 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate, t-amylperoxy 2-ethylhexanoate, t-butylperoxy 2-ethylhexanoate, t-butylperoxyisobutyrate, di-t-butylperoxyhexahydrotetraphthalate, t-amylperoxy3,5,5-trimethylhexanoate, t-butylperoxy3,5,5 -Trimethylhexanoate, t-butyl peroxyacetate , T-butylperoxybenzoate, di-butylperoxytrimethyladipate, etc.) and (7) percarbonate (di-3-methoxybutylperoxydicarbonate, di-2-ethylhexylperoxydicarbonate, bis (4-t-butyl) (Cyclohexyl) peroxydicarbonate, di-isopropylperoxydicarbonate, t-butylperoxyisopropylcarbonate, t-butylperoxy-2-ethylhexylcarbonate, 1,6-bis (t-butylperoxycarbonoyl) hexane, diethylene glycol-bis (t -Butyl peroxycarbonate)) and the like.
Among these, preferred are (1) ketone peroxide, (2) hydroperoxide, (4) dialkyl peroxide and (6) alkyl perester, and particularly preferred are methyl ethyl ketone peroxide and cumene hydroperoxide. Oxides, di-t-butyl peroxide and t-butyl peroxybenzoate.

An oil-soluble redox polymerization initiator is used as the redox polymerization initiator. Examples of peroxide polymerization initiators include oils such as hydroperoxides (t-butylhydroxyperoxide, cumene hydroperoxide, etc.), dialkyl peroxides (such as lauroyl peroxide), and diacyl peroxides (benzoyl peroxide, etc.). Examples thereof include soluble peroxides. Reducing agents include oil-soluble reducing agents such as tertiary amines (triethylamine, tributylamine, etc.), naphthenates, mercaptans (mercaptoethanol, lauryl mercaptan, etc.), organometallic compounds (triethylaluminum, triethylboron, diethylzinc, etc.) Etc. Among these, examples of preferable specific combinations of the peroxide polymerization initiator and the reducing agent include cumene hydroperoxide-triethylaluminum, benzoyl peroxide-triethylamine and the like.

(Organic solvent)
In the method for producing a soluble cross-linked polymer of the present invention, the monomer A having two or more radical polymerizable double bonds in the molecule is polymerized in a first organic solvent under non-reflux.
Examples of the first organic solvent used for the polymerization reaction include the following organic solvents. For example, aromatic hydrocarbon solvents such as benzene, toluene, xylene, ethylbenzene, tetralin; aliphatic or alicyclic hydrocarbon solvents such as n-hexane, n-heptane, mineral spirit, cyclohexane; methyl chloride, bromide Halogen solvents such as methyl, methyl iodide, methylene dichloride, chloroform, carbon tetrachloride, trichloroethylene, perchloroethylene, orthodichlorobenzene; ethyl acetate, butyl acetate, methoxybutyl acetate, methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol Ester or ester ether solvents such as monomethyl ether acetate; diethyl ether, tetrahydrofuran, 1,4-dioxane, ethyl cellosolve, butyl cellosolve, propylene glycol Ether solvents such as nomethyl ether; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, di-n-butyl ketone, cyclohexanone; methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol Alcohol solvents such as 2-ethylhexyl alcohol, benzyl alcohol, ethylene glycol and propylene glycol; amide solvents such as N, N-dimethylformamide and N, N-dimethylacetamide; sulfoxide solvents such as dimethyl sulfoxide, N-methyl Examples include heterocyclic compound solvents such as -2-pyrrolidone, and mixed solvents of two or more of these.
Of these, aromatic hydrocarbon solvents, halogen solvents, ester solvents, ether solvents, ketone solvents, alcohol solvents, amide solvents, sulfoxide solvents and the like are preferable.

Among them, it is preferable to use an organic solvent having a boiling point of 90 ° C. to 200 ° C. under atmospheric pressure, for example, toluene, xylene, orthodichlorobenzene, butyl acetate, dioxane, N, N-dimethylformamide, N, N-dimethylacetamide. Propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, n-propanol, methyl isobutyl ketone, and cyclohexanone.

The amount of the organic solvent is preferably 0.3 to 100 parts by mass, more preferably 0.5 to 50 parts by mass with respect to 1 part by mass of the monomer A from the viewpoint of good temperature control.

The manufacturing method of the present invention, the monomer A, the polymerization initiator B, and the solution containing the second organic solvent, kept at a higher temperature T than the 10-hour half-life temperature T ₁₀ 20 ° C. or more polymerization initiator B It is preferable to polymerize by dropping into the first organic solvent.
When the raw material solution is dropped under reflux, the tip of the dropping tube is exposed to the refluxing liquid that has reached the boiling point, and polymerization may proceed in the dropping tube, which may generate a polymer insoluble in the matrix. On the other hand there was a problem that there was. However, by dropping the raw material solution under non-refluxing as in the present invention, since there is no such problem, the generation of insoluble components can be suppressed. As described above, the use of the dropping method in the polymerization under non-refluxing makes it easier to control the molecular weight.
In addition, the said organic solvent can be used as a 2nd solvent used for a solution.

(Monomer C)
In the production method of the present invention, the solution may further contain a monomer C having one radical polymerizable double bond in the molecule, and by dropping this solution into the first organic solvent, the monomer A and Monomer C may be copolymerized. By copolymerizing with a monofunctional monomer, the molecular weight distribution of the polymer can be stabilized. Hereinafter, preferred specific examples of the monomer C will be described.
Preferable specific examples of the monomer C include, for example, styrene compounds such as styrene and α-methylstyrene; acrylonitrile compounds such as acrylonitrile and methacrylonitrile; N-vinyl compounds such as N-vinylformamide; (meth) acrylamide, N -Methylol (meth) acrylamide, diacetone (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, (meth) acryloylmorpholine, (meth) (Meth) acrylamide compounds such as acrylamide; methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, iso Chill (meth) acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate, amyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, t- Octyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 2-bromoethyl acrylate, 4-chlorobutyl acrylate, cyanoethyl acrylate, 2-acetoxyethyl (meth) acrylate, acetoacetoxyethyl (meth) acrylate, 2-hydroxyethyl (Meth) acrylate, butoxyethyl (meth) acrylate, carbitol (meth) acrylate, cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, benzyl (Meth) acrylate, tridecyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, glycidyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, Dicyclopentanyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2-acryloyloxyethylphthalic acid, methoxy-polyethylene glycol (meth) acrylate, 2-acryloyloxyethyl-2-hydroxy Ethylphthalic acid, 2- (2-ethoxyethoxy) ethyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, ethoxylated phenyl (meth) acrylate Relate, 2- (meth) acryloyloxyethyl succinic acid, nonylphenol EO adduct (meth) acrylate, phenoxy-polyethylene glycol (meth) acrylate, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, lactone modified (meta ) Acrylate, stearyl (meth) acrylate, isoamyl (meth) acrylate, isomyristyl (meth) acrylate, isostearyl (meth) acrylate, lactone-modified (meth) acrylate and other (meth) acrylate compounds; allyl glycidyl ether and other allyl compounds ; Methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, t-butyl vinyl ether , N-octadecyl vinyl ether, 2-ethylhexyl vinyl ether, n-nonyl vinyl ether, dodecyl vinyl ether, octadecyl vinyl ether, cyclohexyl vinyl ether, cyclohexyl methyl vinyl ether, 4-methylcyclohexyl methyl vinyl ether, benzyl vinyl ether, dicyclopentenyl vinyl ether, 2-dicyclopenteno Xyethyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, butoxyethyl vinyl ether, methoxyethoxyethyl vinyl ether, ethoxyethoxyethyl vinyl ether, methoxypolyethylene glycol vinyl ether, tetrahydrofurfuryl vinyl ether, 2-hydroxyethyl vinyl ether, 2-hydroxypro Pyrvinyl ether, 4-hydroxybutyl vinyl ether, 4-hydroxymethylcyclohexyl methyl vinyl ether, diethylene glycol monovinyl ether, polyethylene glycol vinyl ether, chloroethyl vinyl ether, chlorobutyl vinyl ether, chloroethoxyethyl vinyl ether, phenylethyl vinyl ether, phenoxypolyethylene glycol vinyl ether, cyclohexanedimethanol And monovinyl ether compounds such as monovinyl ether and isopropenyl ether-O-propylene carbonate;

Furthermore, the monomer C may have a fluorine atom. Monomer C having a fluorine atom is particularly useful as a surfactant and a surface modifier. As the monomer C having a fluorine atom, one in which a part of the substituents of the monomer C is substituted with fluorine can be used. Specific examples are shown below.
Specific examples include 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3,3-pentafluoropropyl (meth) acrylate, 2- (perfluorobutyl) ethyl (meth) acrylate, 2- (perfluorohexyl) ethyl (meth) acrylate, 2- (perfluorooctyl) ethyl (meth) acrylate, 2- (perfluorodecyl) ethyl (meth) acrylate, 2- (perfluoro-3-methylbutyl) ethyl (Meth) acrylate, 2- (perfluoro-5-methylhexyl) ethyl (meth) acrylate, 2- (perfluoro-7-methyloctyl) ethyl (meth) acrylate, 1H, 1H, 3H-tetrafluoropropyl (meta) ) Acrylate, 1H, 1H, 5H-octafluoropentyl (meth) a Relate, 1H, 1H, 7H-dodecafluoroheptyl (meth) acrylate, 1H, 1H, 9H-hexadecafluorononyl (meth) acrylate, 1H-1- (trifluoromethyl) trifluoroethyl (meth) acrylate, 1H, 1H, 3H-hexafluorobutyl (meth) acrylate, 3-perfluorobutyl-2-hydroxypropyl (meth) acrylate, 3-perfluorohexyl-2-hydroxypropyl (meth) acrylate, 3-perfluorooctyl-2- Hydroxypropyl (meth) acrylate, 3- (perfluoro-3-methylbutyl) -2-hydroxypropyl (meth) acrylate, 3- (perfluoro-5-methylhexyl) -2-hydroxypropyl (meth) acrylate, 3- (Perfluoro- - it can be exemplified methyl octyl) -2-hydroxypropyl (meth) acrylate.

Next, the polymerization method will be described.
(Polymerization method)
In the method for producing a soluble cross-linked polymer of the present invention, monomer A is polymerized in the presence of polymerization initiator B in a non-refluxing manner. The polymerization reaction is carried out under normal pressure, under pressure and under pressure, or under reduced pressure, and is preferably carried out under normal pressure in view of simplicity of apparatus and operation. Further, preferably carried out in an atmosphere of inert gas such as N _2.

Production method of the present invention, since in the 10-hour half-life temperature T ₁₀ than 20 ° C. or more higher than the temperature T of the polymerization initiator B is intended to be polymerized in a non-reflux, the first organic solvent, the polymerization temperature T An organic solvent having a temperature exceeding the boiling point is used. Such a combination of the organic solvent and the polymerization initiator B can be appropriately selected from the specific examples of the organic solvent and the polymerization initiator B.
By polymerizing non-refluxing under the reaction pressure of an organic solvent, the molecular weight can be easily controlled, and furthermore, a polymer can be produced safely even on an industrial scale.

A first organic solvent, by a 10-hour half-life temperature T ₁₀ than 20 ° C. or more higher than the temperature T of the polymerization initiator B, the polymerization initiator decomposition quickly proceeds, the initiator fragment radical polymerization product of B It is possible to control the molecular weight so that the termination reaction with the growth terminal radical proceeds without stagnation and is soluble in the coating composition.

[Soluble cross-linked polymer]
The weight average molecular weight Mw of the soluble crosslinked polymer obtained by the production method of the present invention is 1,000 to 300,000 in terms of polystyrene by gel permeation chromatography. From the viewpoint of compatibility with the coating composition, 1,000 to 50,000 is preferable. The weight average molecular weight Mw and the number average molecular weight Mn can be measured by the methods described in Examples described later.
Further, Mw / Mn as an index of molecular weight distribution is preferably 1.30 to 10.00, and more preferably 1.50 to 6.00. By having such a molecular weight distribution, compatibility with the coating composition is good, and when used as an additive, coating film failures such as bumpy defects can be satisfactorily prevented.

Specific examples of the soluble crosslinked polymer obtained by the production method of the present invention are shown below.

Among them, the polymers (1) and (2) having a fluorine atom are useful as additives such as surface modifiers.

Hereinafter, examples of the present invention will be described. Table 1 lists materials used in the synthesis examples and comparative synthesis examples, their blend ratios, and molecular weights.

(Synthesis Example 1)
(Synthesis Example of Compound 101)
60.0 g of cyclohexanone was charged into a 500 ml three-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube, and the temperature was raised to 102 ° C. Next, a mixed solution consisting of 20.0 g (153.6 mmol) of divinylbenzene, 140.0 g of cyclohexanone and 60.0 g (260.6 mmol) of a polymerization initiator “V-601” (manufactured by Wako Pure Chemical Industries, Ltd.) Was dropped at a constant speed so that the dropping was completed in 120 minutes. After completion of the dropwise addition, the mixture was further stirred for 4 hours and then reprecipitated in 1000 g of hexane to obtain a white solid. Subsequently, after redissolving in 100 g of methyl ethyl ketone and reprecipitating in 1000 g of hexane, the obtained solid was dried under reduced pressure to obtain 30.2 g of Compound 101 which is a polymer of the present invention. The weight average molecular weight Mw of this polymer was 31,800. The weight average molecular weight Mw and the number average molecular weight Mn were calculated in terms of polystyrene by gel permeation chromatography (GPC). A column to which TSKgel SuperHZM-H, TSKgel SuperHZ4000, and TSKgel SuperHZ200 (manufactured by Tosoh Corporation) were connected was used, and tetrahydrofuran was used as a carrier.

(Synthesis Examples 2 to 11)
Compounds 102 to 111, which are the polymers of the present invention, were synthesized in the same manner as in Synthesis Example 1 except that the monomers and blending ratios were changed as shown in Table 1.

(Comparative Synthesis Examples 1 to 4)
Compounds H101 to H104, which are polymers of comparative synthesis examples, were synthesized in the same manner as in Synthesis example 1, except that the monomers and blending ratios were changed as shown in Table 1.

In Table 1, T is the temperature of the organic solvent on the side to be dropped, that represents the polymerization temperature, T ₁₀ represents a 10-hour half-life temperature of the polymerization initiator. TT ₁₀ indicates these differences.

Abbreviations in Table 1 represent the following meanings.
DVB: divinylbenzene EGDMA: ethylene glycol dimethacrylate DCP: tricyclodecane dimethanol dimethacrylate MMA: methyl methacrylate St: styrene V-601: 2,2′-azobis (2-methylpropionic acid) (Wako Pure Chemical Industries, Ltd.) AIBN: Azobisisobutyronitrile V-40: 1,1′-azobis (cyclohexane-1-carbonitrile) (manufactured by Wako Pure Chemical Industries, Ltd.)
DPE: Diphenylethylene

The compounds 102 to 111 that are the polymers of the present invention and the compounds H101 to H104 that are the polymers of the comparative examples are described below.

As shown in Table 1, the hyperbranched polymers obtained by polymerization under non-refluxing of the present invention, for example, the polymers of Synthesis Example 1 and Synthesis Example 3, were polymerized under reflux. Comparative Synthesis Example 3 and Comparative Synthesis Example The molecular weight is small and the variation in molecular weight is small compared to each polymer of 1.
Further, from Synthesis Example 1 and Synthesis Example 10, a highly branched polymer having a smaller molecular weight and a smaller molecular weight variation can be obtained by copolymerizing a monofunctional monomer.
Further, Comparative Synthesis Example 4 in which TT ₁₀ is less than 20 ° C. has a large weight average molecular weight and a large variation in molecular weight even when polymerization is performed under non-reflux.

Next, a hard coat layer was produced using the polymers obtained in the above synthesis examples and comparative synthesis examples. First, preparation of a coating solution for the hard coat layer A-1 of Example 1 will be described.

<Preparation of coating solution for hard coat layer A-1>
Each component was mixed so as to have the following composition to prepare a coating solution for hard coat layer A-1 having a solid content concentration of about 55% by mass.

-Composition of coating solution for hard coat layer A-1-
DPHA: KAYARD DPHA (manufactured by Nippon Kayaku Co., Ltd.) (hexafunctional) 29.6 parts by mass Irucagua 184: alkylphenone photopolymerization initiator (BASF (manufactured))
2.20 parts by mass 3,4-epoxycyclohexylmethyl methacrylate: Cyclomer M100 (manufactured by Daicel Corporation, molecular weight 196)
13.8 parts by mass Compound 1 0.55 parts by mass Compound 101 of the present invention (Synthesis Example 1) 8.3 parts by mass Tinuvin 928: Benzotriazole-based ultraviolet absorber (BASF (manufactured))
0.55 parts by mass MEK (methyl ethyl ketone) 16.7 parts by mass MiBK (methyl isobutyl ketone) 19.8 parts by mass Methyl acetate 8.5 parts by mass

Compound 1 was synthesized by the method described in Example 1 of Japanese Patent No. 4841935. The structural formula of Compound 1 is shown below.

<Preparation of coating solution for hard coat layers A-2 to A-15>
For the hard coat layers A-2 to A-15 of Examples 2 to 11 and Comparative Examples 1 to 4, in the same manner as above except that the compound 101 of the present invention was replaced with the compounds 102 to 111 or H101 to 104 A coating solution was prepared.

<Formation of hard coat layer>
A hard coat film was prepared by using a coating liquid for hard coat layers A-1 to A-15 using a 25 μm-thick triacetyl cellulose film “TJ25” (manufactured by Fuji Film) unwound in a roll form. . Specifically, each coating solution was applied on a support at a conveying speed of 30 m / min by a die coating method using a slot die described in Example 1 of JP-A-2006-122889, and 150 ° C. at 150 ° C. After drying for 2 seconds, using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) with an oxygen concentration of about 0.1% by volume under nitrogen purge, an illuminance of 400 mW / cm ² and an irradiation amount of 500 mJ / cm ² The coating layer was cured by irradiating the ultraviolet ray to form a hard coat layer, and then wound up.
The produced hard coat film was evaluated by the following evaluation method.

{Film thickness of hard coat layer}
The film thickness of the hard coat layer was calculated by measuring the film thickness of a hard coat film produced using a contact-type film thickness meter, and subtracting the thickness of the support measured in the same manner. In all the hard coat films, the film thickness of the hard coat layer was 6.0 μm.

{Scratch defect of hard coat layer}
Fluorescent lamp is irradiated from the back side, 3m ² inspection is performed by transmission visual inspection from the hard coat layer application surface (front surface) side and reflection visual inspection by irradiation of the fluorescent light from the hard coat layer application surface side. A bright spot-like defect was collected. Furthermore, the collected defects are analyzed with a microscope and a Raman / FTIR integrated microspectrometer (trade name “LabRAM-IR”, manufactured by Horiba), and the number of defects having the same composition as the normal part is counted. Then, the value was divided by 3 to calculate the number of bumpy defects per 1 m ² . Evaluation was made based on the following evaluation criteria.

(Evaluation criteria)
A: B pimple defects is zero in terms of per 1 m ^2: C pimple defects are converted by 1-5 generated per 1 m ^2: pimple defects are converted per 1 m ² 6 pieces Has occurred

As shown in Table 2, when the polymer produced by the method for producing the soluble cross-linked polymer according to the present invention was added as a surface modifier for the hard coat layer, it was found that the irregularity of defects was satisfactorily reduced. .
On the other hand, it can be seen that Comparative Examples 1 to 4 polymerized under reflux have a lot of bumpy defects.

In this example, the hard coat layer used in the liquid crystal display device is examined. However, the present invention is not limited to the hard coat layer, and the production method of the present invention is also used for producing other optical films that require high reliability. The produced polymer can be used as an additive.

As described above, according to the method for producing a soluble cross-linked polymer of the present invention, it is possible to obtain a highly branched polymer that suppresses the generation of impurities and has good compatibility with the matrix. When the polymer produced by the production method of the present invention is used as an additive for a coating composition, the compatibility with the coating composition is good, so that a film having a good surface shape in which the occurrence of bumpy defects is suppressed is formed. Obtainable.

Claims

The monomer A having two or more radically polymerizable double bonds in the molecule is added in an amount of 5 to 200 mol% of the polymerization initiator B with respect to 1 mol of the monomer A in the first organic solvent. A method for producing a soluble cross-linked polymer, which is polymerized in the presence of non-refluxing at a temperature 20 ° C. or more higher than the 10-hour half-life temperature of the polymerization initiator B.
The production of the soluble cross-linked polymer according to claim 1, wherein the monomer A is polymerized by dropping a solution containing the monomer A, the polymerization initiator B and the second organic solvent into the first organic solvent. Method.
The method for producing a soluble cross-linked polymer according to claim 2, further comprising monomer C having one radical polymerizable double bond in the molecule in the solution.
The method for producing a soluble crosslinked polymer according to any one of claims 1 to 3, wherein the weight average molecular weight of the soluble crosslinked polymer is 1,000 to 300,000 in terms of polystyrene by gel permeation chromatography.
The method for producing a soluble crosslinked polymer according to claim 4, wherein the weight average molecular weight of the soluble crosslinked polymer is 1,000 to 50,000 in terms of polystyrene by gel permeation chromatography.