KR102159140B1 - Anti-smudge hard coat and anti-smudge hard coat precursor - Google Patents

Abstract

A hard coat comprising a mixture of nanoparticles and a binder, wherein the nanoparticles constitute 40 to 95% by mass of the total mass of the hard coat; 10 to 50% by mass of the nanoparticles have an average particle size in the range of 2 to 200 nm; 50 to 90% by mass of the nanoparticles have an average particle size in the range of 60 to 400 nm; The ratio of the average particle size of nanoparticles having an average particle size in the range of 60 to 400 nm to the average particle size of nanoparticles having an average particle size in the range of 2 to 200 nm is in the range of 2:1 to 200:1 Is; The binder comprises a polyfunctional fluorinated (meth)acrylic compound, a reaction product thereof, or a combination thereof. Polyfunctional fluorinated (meth)acrylic compounds contain cyclic siloxane units. The particle size distribution of the nanoparticles is bimodal or multimodal.

Description

Antifouling hard coat and antifouling hard coat precursor {ANTI-SMUDGE HARD COAT AND ANTI-SMUDGE HARD COAT PRECURSOR}

Cross-reference of related applications

This application claims priority to Japanese Patent Application No. 2012-170999 filed on August 1, 2012, and the disclosure content of the Japanese patent application is incorporated by reference in its entirety.

The present invention relates to an antifouling hard coat and an antifouling hard coat precursor.

Hard coats are used to protect the surfaces of various hard and flexible materials. The hard coat is required not only to have excellent scratch resistance and impact resistance, but also to have optical properties in the case of a transparent material. In addition, it is strongly required that the hard coat surface be provided with antifouling properties.

Hard coat materials containing SiO ₂ nanoparticles modified with a photocurable silane coupling agent are described in U.S. Patent Nos. 5194929 and 7074463.

A hard coat material having an antifouling property and having an easily washable surface obtained by curing a polymerizable composition containing a fluorine compound having a hexafluoropropylene oxide moiety is disclosed in U.S. Patent No. 7718264 and U.S. Patent Application Publication No. 2008 /0124555.

The antifouling properties of the hard coat tend to deteriorate with the wear of the hard coat surface. Therefore, there is still a need for further improvement in antifouling hard coat durability. Accordingly, it is an object of the present invention to provide a hard coat and a hard coat precursor having excellent scratch resistance and durability of antifouling properties.

An embodiment of the present invention provides a hard coat comprising a mixture of nanoparticles and a binder, wherein the nanoparticles constitute 40 to 95% by mass of the total mass of the hard coat; 10 to 50% by mass of the nanoparticles have an average particle size in the range of 2 to 200 nm; 50 to 90% by mass of the nanoparticles have an average particle size in the range of 60 to 400 nm; The ratio of the average particle size of nanoparticles having an average particle size in the range of 60 to 400 nm to the average particle size of nanoparticles having an average particle size in the range of 2 to 200 nm is in the range of 2:1 to 200:1 Is; Binders include polyfunctional fluorinated (meth)acrylic compounds, reaction products thereof, or combinations thereof.

Another embodiment of the present invention provides a hard coat precursor comprising a nanoparticle mixture and a binder, wherein the nanoparticles constitute 40 to 95% by mass of the total weight of the nanoparticles and the binder; 10 to 50% by mass of the nanoparticles have an average particle size in the range of 2 to 200 nm; 50 to 90% by mass of the nanoparticles have an average particle size in the range of 60 to 400 nm; The ratio of the average particle size of nanoparticles having an average particle size in the range of 60 to 400 nm to the average particle size of nanoparticles having an average particle size in the range of 2 to 200 nm is in the range of 2:1 to 200:1 Is; Binders include multifunctional fluorinated (meth)acrylic compounds.

The antifouling hard coat of the present invention filled with a high concentration of nanoparticles shows both excellent scratch resistance and impact resistance while maintaining optical transparency. Additionally, since the binder contains a multifunctional fluorinated (meth)acrylic compound, a reaction product thereof, or a combination thereof, it prevents the adhesion of fingerprints, grease, dust, stains, etc. or in the case of such adhesion. It is possible to easily wash the hard coat, and it is also possible to increase the durability of the antifouling properties. In addition, such an antifouling hard coat can be formed using the antifouling hard coat precursor of the present invention.

The above description should not be considered as disclosing all of the embodiments of the present invention or all of the advantages of the present invention.

1 is a graph showing the result of a simulation between the mass ratio and the filling rate of a small particle group and a large particle group for several particle size combinations (small particle group/large particle group).
2 is a pattern diagram of a wear resistance testing apparatus used in the embodiment.

The present invention will be described in more detail below for the purpose of illustrating representative embodiments of the present invention, but the present invention is not limited to these embodiments.

In the present invention, “(meth)acrylic” refers to “acrylic or methacrylic”, and “(meth)acrylate” refers to “acrylate or methacrylate”.

The hard coat of one embodiment of the present invention contains a mixture of nanoparticles and a binder, and the binder contains a multifunctional fluorinated (meth)acrylic compound, a reaction product thereof, or a combination thereof.

Examples of representative binders contained in the hard coat include resins obtained by polymerization of curable monomers and/or curable oligomers and resins obtained by polymerization of sol-gel glass. More specific examples include acrylic resins, urethane resins, epoxy resins, phenol resins, and polyvinyl alcohol resins. In addition, the curable monomer or curable oligomer may be selected from curable monomers or curable oligomers known in the art, a mixture of two or more curable monomers, a mixture of two or more curable oligomers, or one or two or more It is possible to use a mixture of many curable monomers and one or two or more curable oligomers. In some embodiments, examples of resins include dipentaerythritol pentaacrylate (e.g., available from Sartomer Company (Exton, PA) under the trade name "SR399"), pentaerythritol tri Acrylate isophorone diisocyanate (IPDI) (available from, for example, Nippon Kayaku Co., Ltd. (Tokyo, Japan) under the product name "UX-5000"), urethane acrylate (available from Japan). For example, under the product names "UV1700B" and "UB6300B" from Nippon Synthetic Chemical Industry Co., Ltd. (available from Nippon Synthetic Chemical Industry Co., Ltd. (Osaka, Japan), trimethylhydroxyl diisocyanate/hyde) Roxyethyl acrylate (TMHDI/HEA, available for example from Daicel-Cytec Company, Ltd. under the trade name "Ebecryl 4858"), polyethylene oxide (PEO) modification Bis-A-diacrylate (for example, available from Nippon Kayaku Company, Limited (Tokyo, Japan) under the trade name "R551"), PEO modified bis-A-epoxy acrylate (for example, product name As "3002M", available from Kyoeisha Chemical Co., Ltd. (Osaka, Japan), a silane-based UV curable resin (for example, Nagase Chemtex Corporation under the product name "SK501M" ( Nagase ChemteX Corporation) (available from Osaka, Japan), and 2-phenoxyethyl methacrylate (for example, available from Sartomer Company under the trade name "SR340"), and compounds polymerized using these mixtures This includes. For example, an improvement in adhesion to polycarbonate is observed when 2-phenoxyethyl methacrylate is used within the range of approximately 1.0 to 20% by mass. The simultaneous improvement of the hardness, impact resistance and flexibility of the hard coat is a result of a bifunctional resin (eg PEO modified bis-A-diacrylate "R551") and trimethylhydroxyl diisocyanate/hydroxyethyl acrylic. It is observed when a rate (TMHDI/HEA) (available from Daicel-Cytech Company, Limited (Tokyo, Japan), for example under the product name “Evecryl 4858”) is used.

Typically, the amount of binder in the hard coat is approximately 5 to 60 mass percent of the total mass of the anti-reflective hard coat, and in some embodiments, approximately 10 to 40 mass percent or approximately 15 to 30 mass percent. In the present invention, it is possible to form a hard coat using a relatively small amount of binder.

The hard coat can be further cured with other curable monomers or curable oligomers if necessary. Representative examples of curable monomers or curable oligomers include polyfunctional (meth)acrylic monomers and polyfunctional (meth)acrylic oligomers selected from the group consisting of: (a) compounds having two (meth)acrylic groups, e.g. For example, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol monoacrylate monomethacrylate, ethylene Glycol diacrylate, alkoxylated aliphatic diacrylate, alkoxylated cyclohexane dimethanol diacrylate, alkoxylated hexanediol diacrylate, alkoxylated neopentyl glycol diacrylate, caprolactone modified neopentyl glycol Hydroxypivalate diacrylate, caprolactone modified neopentyl glycol hydroxypivalate diacrylate, cyclohexane dimethanol diacrylate, diethylene glycol diacrylate, dipropylene glycol diacrylate, ethoxylated (10) Bisphenol-A-diacrylate, ethoxylated (3) Bisphenol-A-diacrylate, ethoxylated (30) Bisphenol-A diacrylate, ethoxylated (4) Bisphenol-A-diacrylate, hydride Roxypivalaldehyde modified trimethylol propane diacrylate, neopentyl glycol diacrylate, polyethylene glycol (200) diacrylate, polyethylene glycol (400) diacrylate, polyethylene glycol (600) diacrylate, propoxylated (propoxylated) neopentyl glycol diacrylate, tetraethylene glycol diacrylate, tricyclodecane dimethanol diacrylate, triethylene glycol diacrylate, tripropylene glycol diacrylate, and the like; (b) compounds having three (meth)acrylic groups, such as glycerol triacrylate, trimethylol propane triacrylate, ethoxylated triacrylate (e.g., ethoxylated (3) trimethylol propane triacrylic Rate, ethoxylated (6) trimethylol propane triacrylate, ethoxylated (9) trimethylol propane triacrylate, ethoxylated (20) trimethylol propane triacrylate, etc.), pentaerythritol triacrylate, Propoxylated triacrylate (e.g., propoxylated (3) glyceryl triacrylate, propoxylated (5.5) glyceryl triacrylate, propoxylated (3) trimethylol propane triacrylate, pro Foxylated (6) trimethylol propane triacrylate, etc.), trimethylol propane triacrylate, tris-(2-hydroxyethyl) isocyanurate triacrylate, etc.; (c) Compounds having four (meth)acrylic groups, such as ditrimethylol propane tetraacrylate, dipentaerythritol pentaacrylate, ethoxylated (4) pentaerythritol tetraacrylate, pentaerythritol tetraacrylate Rate, caprolactone-modified dipentaerythritol hexaacrylate, and the like; (d) oligomeric (meth)acrylic compounds such as urethane acrylate, polyester acrylate, epoxy acrylate, and the like; The above polyacrylamide analogs; And combinations thereof. Such compounds are commercially available, and at least some of these compounds are Sartomer Company, UCB Chemicals Corporation (Smyrna, Georgia, USA), Aldrich Chemical Company (Milwaukee, Wisconsin). It is available from et al. Examples of other useful (meth)acrylates include hydantoin moiety-containing poly(meth)acrylates such as those disclosed in U.S. Patent No. 4262072.

Preferred curable monomers or curable oligomers contain 3 or more (meth)acrylic groups. Preferred commercially available curable monomers or curable oligomers are those available from Sartomer Company, for example trimethylol propane triacrylate (TMPTA) (product name: "SR351"), pentaerythritol tri/tetraacrylate (PETA) ( Product names: "SR444" and "SR295"), and dipentaerythritol pentaacrylate (product name: "SR399"). In addition, mixtures of polyfunctional (meth)acrylates and monofunctional (meth)acrylates, for example mixtures of PETA and 2-phenoxyethyl acrylate (PEA) can also be used.

The nanoparticle mixture contained in the hard coat constitutes approximately 40 to 95 mass% of the total mass of the hard coat, and in some embodiments, approximately 60 to 90 mass% or approximately 70 to 85 mass% of the total mass of the hard coat. Make up. The nanoparticle mixture comprises approximately 10 to 50% by mass of nanoparticles having an average particle size in the range of approximately 2 to 200 nm (hereinafter referred to as a small particle group or first nanoparticle group) and approximately 50 to 90% by mass. , Nanoparticles having an average particle size in the range of approximately 60 to 400 nm (hereinafter referred to as a large particle group or a second nanoparticle group). For example, the nanoparticle mixture comprises a first group of nanoparticles having an average particle size of approximately 2 to 200 nm and a second group of nanoparticles having an average particle size of approximately 60 to 400 nm in a mass ratio of approximately 10:90 to 50:50. It can be obtained by mixing with.

The average particle size of the nanoparticles can be measured using a transmission electron microscope (TEM) using a technique commonly used in the art. In the measurement of the average particle size of the nanoparticles, the sol sample for TEM imaging was the top surface of a mesh lace-like carbon (available from Ted Pella Inc. (Reading, CA)). It can be prepared by dropping a sol sample into a 400 mesh copper TEM grid having an ultra-thin carbon substrate on top. Some liquid droplets can be removed by contacting the droplets with the filter paper as well as the side or bottom of the grid. The remaining sol solvent can be removed by heating the solution or standing at room temperature. This allows the particles to be on an ultra-thin carbon substrate and to be imaged with minimal interference from the substrate. Then, TEM images can be recorded at many locations across the entire grid. Sufficient images are recorded to enable measurement of the particle size of 500 to 1000 particles. Next, the average particle size of the nanoparticles can be calculated based on the particle size measurements of each sample. TEM images were obtained using a high-resolution transmission electron microscope (using a LaB ₆ light source) operating at 300 KV (available from Hitachi High Technologies Corporation under the product name "Hitachi H-9000") Can be. Images were taken with a camera (eg product name “GATAN ULTRASCAN CCD”: (Model No. 895, 2k x 2k chip) from Gatan, Inc.) (Pleasanton, CA). Available). Images can be taken at 50,000 times and 100,000 times magnification. For some samples, the image can be taken at a magnification of 300,000 times.

Typically nanoparticles are inorganic particles. Examples of the inorganic particles include inorganic oxides such as alumina, tin oxide, antimony oxide, silica (SiO, SiO ₂ ), zirconia, titania, ferrite, and the like, mixtures thereof, or mixed oxides thereof; Metal vanadate, metal tungstate, metal phosphate, metal nitrate, metal sulfate, metal carbide, and the like. The inorganic oxide sol can be used as inorganic oxide nanoparticles. For example, in the case of silica nanoparticles, a silica sol obtained using liquid glass (sodium silicate solution) as a starting material can be used. The silica sol obtained from liquid glass can have a very narrow particle size distribution depending on the production conditions; Therefore, when such a silica sol is used, a hard coat having desired properties can be obtained by more accurately controlling the filling rate of the nanoparticles in the hard coat.

The average particle size of the small group of particles is in the range of approximately 2 to 200 nm. The particle size is preferably approximately 2 to 150 nm, approximately 3 to 120 nm, or approximately 5 to 100 nm. The average particle size of the large particle group is in the range of approximately 60 to 400 nm. The particle size is preferably approximately 65 to 350 nm, approximately 70 to 300 nm, or approximately 75 to 200 nm.

The nanoparticle mixture comprises a particle size distribution of two or more different types of nanoparticles. The particle size distribution of the nanoparticle mixture may exhibit bimodality or multimodality having peaks in the average particle size of the small particle group and the average particle size of the large particle group. In addition to the particle size distribution, the nanoparticles may be the same or different from each other (eg, compositionally surface-modified or not surface-modified). In some embodiments, the ratio of the average particle size of nanoparticles having an average particle size in the range of approximately 2 to 200 nm to the average particle size of nanoparticles having an average particle size in the range of approximately 60 to 400 nm is 2:1 to 200 :1, and in some embodiments, 2.5:1 to 100:1 or 2.5:1 to 25:1. Examples of preferred combinations of average particle size include 5 nm/190 nm, 5 nm/75 nm, 20 nm/190 nm, 5 nm/20 nm, 20 nm/75 nm, 75 nm/190 nm, and 5 nm/20 A combination of nm/190 nm is included. By the use of a mixture of nanoparticles of different sizes, it is possible to fill the hard coat with a large amount of nanoparticles and thereby increase the hardness of the hard coat.

In addition, the transparency (turbidity, etc.) and hardness can be varied, for example, by selecting the type, amount, size and ratio of the nanoparticles. In some embodiments, a hard coat can be obtained having both desired transparency and hardness.

The mass ratio (%) of the small particle group and the large particle group can be selected according to the particle size used or the combination of the particle size used. The preferred mass ratio can be selected according to the particle size used or the combination of particle sizes used by using software available under the product name "CALVOLD2", for example, to a combination of particle sizes (small particle group/large particle group). So it can be selected based on a simulation between the mass ratio and the filling rate of a small particle group and a large particle group ("Verification of a Model for Estimating the Void Fraction in a Three-Component Randomly Packed Bed," M. Suzuki and T. Oshima: Powder Technol., 43, 147-153 (1985)). The simulation results are shown in FIG. 1. According to this simulation, the mass ratio (small particle group: large particle group) in the combination of 5 nm/190 nm is approximately 45:55 to 13:87 or approximately 40:60 to 15:85. The mass ratio in the combination of 5 nm/75 nm is preferably about 45:55 to 10:90 or about 35:65 to 15:85. The mass ratio in the combination of 20 nm/190 nm is preferably approximately 45:55 to 10:90. The mass ratio in the combination of 5 nm/20 nm is preferably approximately 50:50 to 20:80. The mass ratio in the combination of 20 nm/75 nm is preferably approximately 50:50 to 22:78. The mass ratio in the combination of 75 nm/190 nm is preferably approximately 50:50 to 27:73.

In some embodiments, the use of a preferred combination of nanoparticles and particle size allows an increase in the amount of nanoparticles filling the hard coat and adjustment of the transparency and hardness of the resulting hard coat.

Typically, the thickness of the hard coat is in the range of approximately 80 nm to 30 μm (in some embodiments, approximately 200 nm to 20 μm or approximately 1 to 10 μm), but the hard coat is sometimes, even from these ranges. It can also be used effectively when you get away from it. The use of mixtures of nanoparticles of different sizes sometimes makes it possible to obtain hard coats with greater thickness and higher hardness.

The surface of the nanoparticles can be modified using a surface treatment agent if necessary. Typically the surface treatment agent has a first end bond to the particle surface (either through covalent bonding, ionic bonding or strong physical adsorption) and a second end that reacts with the resin during curing and/or provides particle compatibility with the resin. . Examples of the surface treatment agent include alcohol, amine, carboxylic acid, sulfonic acid, phosphonic acid, silane, and titanate. The preferred type of treatment agent is determined, in part, by the chemistry of the nanoparticle surface. When silica or other siliceous fillers are used as nanoparticles, silanes are preferred. Silanes and carboxylic acids are preferred for metal oxides. Surface modification may be carried out before, during, or after mixing with the curable monomer or curable oligomer. When silane is used, the reaction between the silane and the nanoparticle surface is preferably carried out prior to mixing with the curable monomer or curable oligomer. The required amount of the surface treatment agent is determined by several factors, such as the particle size and type of the nanoparticles and the molecular weight and type of the surface treatment agent. It is typically preferred to deposit a layer of surface treatment agent on the surface of the particles. In addition, the required deposition procedure or reaction conditions are determined by the surface treatment agent used. When silane is used, it is preferable to perform the surface treatment at high temperature under acidic or basic conditions for approximately 1 to 24 hours. Typically, high temperatures or long periods of time are unnecessary in the case of surface treatment agents such as carboxylic acids.

Representative examples of the surface treatment agent include isooctyltrimethoxysilane, polyalkylene oxide alkoxysilane (for example, under the product name "SILQUEST A1230", Momentive Specialty Chemicals, Inc. (Momentive Specialty Chemicals, Inc.). ) (Available from Columbus, Ohio), N-(3-triethoxysilyl propyl) methoxyethoxy ethoxyethyl carbamate, 3-(methacryloyloxy) propyl trimethoxysilane ( For example, available from Alfa Aesar (Ward Hill, MA) under the product name "Silquest A174"), 3-(acryloyloxy)propyl trimethoxysilane, 3-(methacryl Royloxy) propyl triethoxysilane, 3-(methacryloyloxy) propyl methyl dimethoxysilane, 3-(acryloyloxy) propyl methyl dimethoxysilane, 3-(methacryloyloxy) Propyl dimethyl ethoxysilane, 3-(methacryloyloxy) propyl dimethyl ethoxysilane, vinyl dimethyl ethoxysilane, phenyl trimethoxysilane, n-octyl trimethoxysilane, dodecyl trimethoxysilane , Octadecyl trimethoxysilane, propyl trimethoxysilane, hexyl trimethoxysilane, vinyl methyl diacetoxysilane, vinyl methyl diethoxysilane, vinyl triacetoxysilane, vinyl triethoxysilane, vinyl triisopro Foxysilane, vinyl trimethoxysilane, vinyl triphenoxysilane, vinyl tri(t-butoxy) silane, vinyl tri(isobutoxy) silane, vinyl triisopropeneoxysilane, vinyl tris-(2-methoxy) Ethoxy) silane, styryl ethyl trimethoxysilane, mercapto propyl trimethoxysilane, 3-glycidoxy propyl trimethoxysilane, acrylic acid, methacrylic acid, oleic acid, stearic acid, dodecanoic acid, 2-[2 -(2-methoxyethoxy)ethoxy]acetic acid (MEEAA), β-carboxyethyl acrylate, 2-(2-methoxyethoxy)acetic acid, and methoxy phenyl acetic acid and mixtures thereof do.

The binder of the antifouling hard coat of the present invention contains a multifunctional fluorinated (meth)acrylic compound, a reaction product thereof, or a combination thereof, which provides antifouling properties to the surface of the hard coat and facilitates cleaning (e.g., Anti-fingerprint, oil resistance, dust and/or antifouling function). The multifunctional fluorinated (meth)acrylic compound has a plurality of (meth)acrylic groups, and thus can react with the curable monomer or curable oligomer as a crosslinking agent or non-covalently interact with the functional groups contained in the binder at a plurality of sites. I can. As a result, the durability of the antifouling property can be increased. When a multifunctional fluorinated (meth)acrylic compound is used, it may also be possible to increase the scratch resistance by reducing the coefficient of friction of the hard coat surface. When a multifunctional fluorinated (meth)acrylic compound having three or more (meth)acrylic groups is used, it is possible to further increase the durability of antifouling properties.

Since the perfluoroether group provides excellent antifouling properties to the hard coat, the multifunctional fluorinated (meth)acrylic compound is preferably a perfluoroether compound having at least two (meth)acrylic groups.

For example, the polyfunctional perfluoroether (meth)acrylate described in Japanese Patent Application Publication No. 2008-538195 and Japanese Patent Application Publication No. 2008-527090 is a perfluoroether having two or more (meth)acrylic groups. It can be used as a compound. In the specific example of such a multifunctional perfluoroether (meth)acrylate

HFPO-C(O)N(H)CH(CH ₂ OC(O)CH=CH ₂ ) ₂ ;

HFPO-C(O)N(H)C(CH ₂ CH ₃ )(CH ₂ OC(O)CH=CH ₂ ) ₂ ;

HFPO-C(O)NHC(CH ₂ OC(O)CH=CH ₂ ) ₃ ;

HFPO-C(O)N(CH ₂ CH ₂ OC(O)CH=CH ₂ ) ₂ ;

HFPO-C(O)NHCH ₂ CH ₂ N(C(O)CH=CH ₂ )CH ₂ OC(O)CH=CH ₂ ;

HFPO-C(O)NHCH(CH ₂ OC(O)CH=CH ₂ ) ₂ ;

HFPO-C(O)NHC(CH ₃ )(CH ₂ OC(O)CH=CH ₂ ) ₂ ;

HFPO-C(O)NHC(CH ₂ CH ₃ )(CH ₂ OC(O)CH=CH ₂ ) ₂ ;

HFPO-C(O)NHCH ₂ CH(OC(O)CH=CH ₂ )CH ₂ OC(O)CH=CH ₂ ;

HFPO-C(O)NHCH ₂ CH ₂ CH ₂ N(CH ₂ CH ₂ OC(O)CH=CH ₂ ) ₂ ;

HFPO-C(O)OCH ₂ C(CH ₂ OC(O)CH=CH ₂ ) ₃ ;

HFPO-C(O)NH(CH ₂ CH ₂ N(C(O)CH=CH ₂ )) ₄ CH ₂ CH ₂ NC(O)-HFPO;

CH ₂ =CHC(O)OCH ₂ CH(OC(O)HFPO)CH ₂ OCH ₂ CH(OH)CH ₂ OCH ₂ CH(OC(O)HFPO)CH ₂ OCOCH=CH ₂ ;

HFPO-CH ₂ O-CH ₂ CH(OC(O)CH=CH ₂ )CH ₂ OC(O)CH=CH ₂ and the like.

In the present invention, HFPO is a perfluoroether moiety represented by F(CF(CF3)CF ₂ O) _n CF(CF ₃ )- (n is 2 to 15) and a compound containing such a perfluoroether moiety Say.

The multifunctional perfluoropolyether (meth)acrylates described above are, for example, poly(hexafluoropropylene oxide) esters, such as HFPO-C(O)OCH ₃ or poly(hexafluoropropylene oxide) acids. Halide: HFPO-C(O)F is reacted with three or more alcohols or substances containing primary or secondary amino groups to form HFPO-amide polyols or polyamines, HFPO-ester polyols or polyamines, HFPO-amides, or mixed amines and A first step of producing an HFPO-ester having an alcohol group, and (meth)acrylated using a (meth)acryloyl halide, (meth)acrylic anhydride or (meth)acrylic acid in the alcohol group and/or amine group It can be synthesized through the second step. Alternatively, the multifunctional perfluoropolyether (meth)acrylate is HFPO-C(O)N(H)CH ₂ CH ₂ CH ₂ N(H)CH ₃ and trimethylol propane triacrylate (TMPTA) And it may be synthesized using a Michael-type addition reaction of a reactive perfluoroether, such as an adduct of poly(meth)acrylate.

Preferred polyfunctional fluorinated (meth)acrylic compounds are divalent in the perfluoroether moiety and both directly or through other groups or bonds (ether bonds, ester bonds, amide bonds, urethane bonds, etc.) It is bound to the end of. While not wishing to be bound by any particular theory, such compounds improve the durability of antifouling properties by forming a hard bond with the hard coat, and the perfluoroether sites between the (meth)acrylic groups are directed in the in-plane direction. It is thought that it moves to the hard coat surface so as to be easily oriented. As a result, sufficient expression of antifouling properties may be possible.

Polyfunctional fluorinated (meth)acrylic compounds may contain siloxane units. When the nanoparticles are inorganic oxides, polyfunctional fluorinated (meth)acrylic compounds containing siloxane units are not only reacted between (meth)acrylic groups and curable monomers or curable oligomers, but also interactions between siloxane bonds and nanoparticles It is also kept more rigid on the hard coat, which is thought to further increase the durability of the antifouling properties. Preferably, the nanoparticles are silica nanoparticles that are chemically similar to siloxane bonds and have high affinity with siloxane bonds.

Polyfunctional fluorinated (meth)acrylic compounds containing siloxane units are, for example, perfluoropolyether compounds having one or two or more unsaturated ethylene groups in the presence of three or more Si-H To a straight or cyclic oligosiloxane or polysiloxane containing a bond (hydrogen siloxane), added (hydrosilylation) in a volume less than 1 equivalent relative to the Si-H bond, and similarly, hydroxyl group-containing unsaturated ethylene It can be synthesized by adding the compound to the remaining Si-H bond in the presence of a platinum catalyst (hydrosilylation), and then reacting the hydroxyl group with an epoxy (meth)acrylate, urethane (meth)acrylate, etc. . The partial molecular weight of the perfluoroether moiety calculated from the formula may be 500 to 30,000.

In order to sufficiently express the antifouling property imparted by the fluorinated moiety, the siloxane unit is preferably a cyclic siloxane unit derived from tetramethyl cyclotetrasiloxane, pentamethyl cyclopentasiloxane, or the like. The number of silicon atoms constituting the cyclic siloxane unit is preferably 3 to 7.

An example of a polyfunctional fluorinated (meth)acrylic compound containing a siloxane unit is a perfluoropolyether compound having two or more (meth)acrylic groups, as described in Japanese Patent Application Laid-Open No. 2010-285501, for example. . For example, in this Japanese patent application publication, the compound represented by Chemical Formula 19 and Chemical Formula 21 has a cyclic siloxane having 4 silicon atoms, each divalent perfluoropolyether group, that is, -CF ₂ (OCF ₂ CF ₂ ) _p (OCF ₂ ) _q OCF _2- (p/q=0.9, p+q≒45) is bonded to both ends, and three acryloyloxy groups are bonded to each of these cyclic siloxanes through a urethane group. , Which is suitable for the antifouling hard coat of the present invention.

When polyfunctional fluorinated (meth)acrylic compounds and reaction products thereof are regarded as multifunctional fluorinated (meth)acrylic compounds corresponding to the reaction product, the compounds and reaction products are, for example, nanoparticles, curable monomers and curable It is contained in the binder within a range of approximately 0.01 to 20 parts by mass (in some embodiments, approximately 0.1 to 10 parts by mass or approximately 0.2 to 5 parts by mass) based on a total of 100 parts by mass of the oligomer.

The binder of the hard coat is known additives, such as UV absorbers, defogging agents, leveling agents, UV reflectors, antistatic agents, etc., if necessary, or other agents that provide a function to facilitate cleaning. It may contain additional chemicals.

In some embodiments, an ultraviolet absorber is contained in the binder of the hard coat. The ultraviolet absorber can be mixed with a curable monomer or a curable oligomer. Known agents can be used as ultraviolet absorbers. For example, ultraviolet absorbers, such as benzophenone-based absorbents (for example, available from BASF AG under the product name "Uvinul 3050"), benzotriazole-based absorbents (for example, Available from BASF AG under the product name "Tinuvin 928"), triazine-based absorbent (for example, available from BASF AG under the product name "Tinuvin 1577"), salicylate-based absorbent, diphenyl acrylate A based absorber, and a cyanoacrylate based absorber and hindered amine light stabilizer (HALS) (available from BASF AG under the product name "Tinuvin 292", for example) can be used. By using a known ultraviolet absorber and a hindered amine light stabilizer in combination, it is possible to further increase the ultraviolet absorbency of the hard coat as compared to when each of the above components is used alone.

The amount of the ultraviolet absorber to be added is, for example, approximately 0.01 to 20 parts by mass (in some embodiments, approximately 0.1 to 15 parts by mass or approximately 0.2 to 10 parts by mass) based on 100 parts by mass of the total nanoparticles, curable monomer and curable oligomer. May be within range. In some embodiments, a hard coat containing an ultraviolet absorber can achieve an ultraviolet transmittance of less than 3%.

In some embodiments, the anti-fog agent is contained in the binder of the hard coat. The anti-fog agent may be mixed with a curable monomer or a curable oligomer. Anionic, cationic, nonionic or amphoteric surfactants can be used as anti-fog agents, examples of which include sorbitan-based surfactants such as sorbitan monostearate, sorbitan monomyristate, sorbitan monopalmitate. , Sorbitan monobehenate, and esters of sorbitan, alkylene glycol condensates and fatty acids; Glycerin surfactants such as glycerin monopalmitate, glycerin monostearate, glycerin monolaurate, diglycerin monopalmitate, glycerin dipalmitate, glycerin distearate, glycerin monopalmitate/monostearate, triglycerin Monostearate, triglycerin distearate, or alkylene oxide adducts thereof; Polyethylene glycol-based surfactants such as polyethylene glycol monostearate, polyethylene glycol monopalmitate, and polyethylene glycol alkyl phenyl ether; Trimethylol propane surfactants such as trimethylol propane monostearate; Pentaerythritol surfactants, such as pentaerythritol monopalmitate and pentaerythritol monostearate; Alkylene oxide adducts of alkyl phenols; Sorbitan/glycerin condensates and esters of fatty acids and sorbitan alkylene glycol condensates and esters of fatty acids; Diglycerol dioleate sodium lauryl sulfate, sodium dodecyl benzene sulfonate, cetyl trimethyl ammonium chloride, dodecylamine hydrochloride, lauryl amide laurate ethyl phosphate, triethyl cetyl ammonium iodide, oleylamino diethyl Amine hydrochloride, dodecylpyridinium salt and isomers thereof. The anti-fog agent may also have functional groups that react with the curable monomer or curable oligomer.

The amount of the anti-fog agent added is, for example, about 0.01 to 20 parts by mass (in some embodiments, about 0.1 to 15 parts by mass or about 0.2 to 10 parts by mass) based on 100 parts by mass of the total of nanoparticles, curable monomer and curable oligomer. May be within range.

Hard coat precursors that can be used in the formation of the hard coat include the nanoparticle mixtures described above, binders containing curable monomers and/or curable oligomers and polyfunctional fluorinated (meth)acrylic compounds, reaction initiators, and solvents, if necessary, e.g. For example, methyl ethyl ketone (MEK), 1-methoxy-2-propanol (MP-OH), and the like, and the additives described above, such as an ultraviolet absorber, an anti-fog agent, a leveling agent, an ultraviolet reflector, an antistatic agent, etc. Contains. The hard coat precursors of some embodiments contain a mixture of nanoparticles and a binder, wherein the nanoparticles make up 40 to 95% by mass of the total mass of the nanoparticles and the binder. 10 to 50% by mass of the nanoparticles have an average particle size in the range of 2 to 200 nm, and 50 to 90% by mass of the nanoparticles have an average particle size within the range of 60 to 400 nm. The ratio of the average particle size of nanoparticles having an average particle size in the range of 60 to 400 nm to the average particle size of nanoparticles having an average particle size in the range of 2 to 200 nm is in the range of 2:1 to 200:1, The binder contains a multifunctional fluorinated (meth)acrylic compound.

As is generally known in the art, hard coat precursors can be prepared by combining certain components of the hard coat precursor. For example, the hard coat precursor is prepared by mixing a curable monomer and/or a curable oligomer in a solvent with a reaction initiator and adding a solvent to prepare two or more different sized modified or unmodified nanoparticle sols having a desired solid content. Can be manufactured. For example, photoinitiators or thermal polymerization initiators known in the art can be used as the reaction initiator. Depending on the curable monomer and/or curable oligomer used, it may not be necessary to use a solvent.

When surface-modified nanoparticles are used, the hard coat precursor can be prepared, for example, as follows. Inhibitors and surface modifiers are added to the solvent in a container (eg, in a glass vial), and the resulting mixture is added to an aqueous solution in which the nanoparticles are dispersed and then stirred. The container is sealed and placed in an oven at high temperature (eg 80° C.) for several hours (eg 16 hours). Next, for example, a rotary evaporator is used at high temperature (eg 60° C.) to remove moisture from the solution. The remaining moisture is removed from the solution by pouring a solvent into the solution and then evaporating the solution. Sometimes it is desirable to repeat the rear half of the above steps several times. The concentration of the nanoparticles can be adjusted to a desired concentration (% by mass) by adjusting the volume of the solvent.

Techniques for applying a hard coat precursor (solution) to the surface of a substrate are known in the art, and examples include bar coating, dip coating, spin coating, capillary coating, spray coating, and gravure. (gravure) coating, screen printing, etc. The coated hard coat precursor is dried if necessary, and may be cured using a polymerization method known in the art, such as an optical polymerization method using an ultraviolet ray or an electron beam, a thermal polymerization method, or the like. In this way, a hard coat can be formed on the substrate.

Examples of representative substrates to which the antifouling hard coat of the present invention is applied include films, plastics (polymer plates), flat glass and metal sheets. The film can be transparent or opaque. In the present invention, "transparent" means that the total light transmittance in the visible range (380 to 780 nm) is 90% or more, and "opaque" means that the total light transmittance in the visible range (380 to 780 nm) is It means less than 90%. Examples of representative films include polyolefins (e.g., polyethylene (PE), polypropylene (PP), etc.), polyurethanes, polyesters (e.g., polyethylene terephthalate (PET), etc.), poly(meth)acrylates ( For example, polymethyl methacrylate (PMMA), etc.), polyvinyl chloride, polycarbonate, polyamide, polyimide, phenol resin, cellulose diacetate, cellulose triacetate, polystyrene, styrene-acrylonitrile copolymer , Acrylonitrile-butadiene-styrene copolymer (ABS), epoxy, polyacetate or a film formed from glass. The plastic (polymer plate) can be transparent or opaque. Examples of representative plastics (polymer plates) include polycarbonate (PC), polymethylmethacrylate (PMMA), styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymer (ABS), PC And plastics formed from a blend of PMMA, or a laminate of PC and PMMA. The metal sheet can be flexible or rigid. In the present invention, "flexible metal sheet" refers to a metal sheet that does not undergo significant irreversible changes and can be subjected to mechanical stress, such as bending or stretching, and "rigid metal sheet" refers to a metal sheet that does not undergo significant irreversible changes and is bent. Or it refers to a metal sheet that cannot be subjected to mechanical stress such as stretching. A typical flexible metal sheet is one made of aluminum. Representative rigid metal sheets include sheets made of aluminum, nickel, nickel-chromium, and stainless steel.

The thickness of the film is in the range of approximately 5 to 500 μm (in some embodiments, approximately 10 to 200 μm or approximately 25 to 100 μm). The thickness of the plastic (polymer plate) is in the range of approximately 0.5 mm to 10 cm (in some embodiments, approximately 0.5 to 5 mm or approximately 0.5 to 3 mm). The thickness of the pane or metal sheet is in the range of approximately 5 to 500 μm or approximately 0.5 mm to 10 cm (in some embodiments, approximately 0.5 to 5 mm or approximately 0.5 to 3 mm). These substrates can sometimes be used effectively even when the thickness is outside the range described above.

The hard coat can be applied to multiple surfaces of the substrate. In addition, a plurality of hard coat layers can be applied to the surface of the substrate.

In some embodiments, the surface of the substrate is primed or a primer layer is disposed on the surface of the substrate to improve adhesion between the hard coat and the substrate. In particular, when the substrate contains a material having poor adhesion, for example polypropylene, polyvinyl chloride, or the like, or when the substrate is a metal sheet, a priming or primer layer is particularly effective.

Priming is known in the art, and examples include plasma treatment, corona discharge treatment, flame treatment, electron beam irradiation, roughening, ozone treatment, chemical oxide treatment using chromic acid or sulfuric acid, and the like.

Examples of materials used in the primer layer include (meth)acrylic resins (homopolymers of (meth)acrylates, copolymers of two or more types of (meth)acrylates, or (meth)acrylates and other polymerizable monomers. Copolymer), urethane resin (e.g., a 2-solution curable urethane resin consisting of a polyol and an isocyanate curing agent), (meth)acrylic-urethane copolymer (e.g., acrylic-urethane block copolymer), polyester resin , Butyral resins, vinyl chloride-vinyl acetate copolymers, ethylene-vinyl acetate copolymers, chlorinated polyolefins, such as chlorinated polyethylene or chlorinated polypropylene, and copolymers and derivatives thereof (e.g., chlorinated Ethylene-propylene copolymers, chlorinated ethylene-vinyl acetate copolymers, acrylic-modified chlorinated polypropylene, maleic anhydride-modified chlorinated polypropylene, and urethane-modified chlorinated polypropylene), and the like. When the substrate is a polypropylene film, it is advantageous that the primer contains chlorinated polypropylene or modified chlorinated polypropylene.

The primer layer may be formed by applying a primer solution prepared by dissolving the aforementioned resin in a solvent using a method known in the art, and then drying the solution. Typically, the thickness of the primer layer is in the range of approximately 0.1 to 20 μm (in some embodiments, approximately 0.5 to 5 μm).

In addition, the substrate may have a printing layer, a colored layer, a metal thin film layer or the like having a desired pattern, if necessary.

Articles containing the hard coat of the present invention may also have an adhesive layer if desired. The adhesive layer can be disposed on the opposite substrate surface, for example when viewed from the hard coat. Rubber adhesives, acrylic adhesives, polyurethane adhesives, polyolefin adhesives, polyester adhesives, and silicone adhesives or pressure sensitive adhesives known in the art can be used as the adhesive layer. The adhesive layer may be formed by directly applying or extruding the adhesive and pressure sensitive adhesive on the substrate, or the adhesive layer formed by applying the adhesive and pressure sensitive adhesive to a release liner may be laminated and transferred to the substrate.

The thickness of the adhesive layer comprising the adhesive or pressure sensitive adhesive is typically in the range of approximately 1 to 100 μm (in some embodiments, approximately 5 to 75 μm or approximately 10 to 50 μm). The adhesive or pressure sensitive adhesive may also contain the ultraviolet absorber described above.

The hard coat and/or adhesive layer may also be provided with release liners known in the art, if necessary. Materials known in the art and prepared by performing a silicone treatment or the like on a paper or polymer film can be used as a release liner.

The antifouling hard coat of the present invention is, for example, an optical display (e.g., a cathode ray tube (CRT) and light-emitting diode (LED) display), a plastic card, a lens of a camera. Or a body, a fan, a doorknob, a faucet handle, a mirror, and home appliances, such as a vacuum cleaner, a washing machine, and the like; It is useful in personal digital assistants (PDAs), mobile phones, liquid crystal display (LCD) panels, devices with touch sensor screens, detachable computer screens, and the like, and the body of such devices. In addition, the antifouling hard coat of the present invention can be used, for example, for furniture, doors and windows, toilets and bathrooms, inside/outside of vehicles, lenses (of cameras or glasses), or solar-powered panels (solar-powered panels). Panel) may also be useful.

Various embodiments are provided including a hard coat or hard coat precursor.

Embodiment 1 is a hard coat comprising a nanoparticle mixture and a binder; The nanoparticles make up 40 to 95% by mass of the total mass of the hard coat; 10 to 50% by mass of the nanoparticles have an average particle size in the range of 2 to 200 nm; 50 to 90% by mass of the nanoparticles have an average particle size in the range of 60 to 400 nm; The ratio of the average particle size of nanoparticles having an average particle size in the range of 60 to 400 nm to the average particle size of nanoparticles having an average particle size in the range of 2 to 200 nm is in the range of 2:1 to 200:1 Is; The particle size distribution of the nanoparticles is bimodal or multimodal; Binders include polyfunctional fluorinated (meth)acrylic compounds, reaction products thereof, or combinations thereof; Polyfunctional fluorinated (meth)acrylic compounds contain cyclic siloxane units.

Embodiment 2 is the hard coat of Embodiment 1 in which the nanoparticles are surface-modified nanoparticles.

Embodiment 3 is the hard coat of Embodiment 1 or Embodiment 2, wherein the polyfunctional fluorinated (meth)acrylic compound is a perfluoroether compound having two or more (meth)acrylic groups.

Embodiment 4 is the hard coat of any one of Embodiments 1 to 3 in which the multifunctional fluorinated (meth)acrylic compound has three or more (meth)acrylic groups.

Embodiment 5 is the hard coat of any one of Embodiments 1 to 4, wherein the nanoparticles are inorganic oxide nanoparticles, and the multifunctional fluorinated (meth)acrylic compound contains siloxane units.

Embodiment 6 is the hard coat of any one of Embodiments 1 to 5, wherein the nanoparticles are silica nanoparticles.

Embodiment 7 is the hard coat of any one of Embodiments 1 to 6, wherein the binder further contains an ultraviolet absorber.

Embodiment 8 is a hard coat precursor comprising a nanoparticle mixture and a binder; The nanoparticles make up 40 to 95% by mass of the total mass of the nanoparticles and the binder; 10 to 50% by mass of the nanoparticles have an average particle size in the range of 2 to 200 nm; 50 to 90% by mass of the nanoparticles have an average particle size in the range of 60 to 400 nm; The ratio of the average particle size of nanoparticles having an average particle size in the range of 60 to 400 nm to the average particle size of nanoparticles having an average particle size in the range of 2 to 200 nm is in the range of 2:1 to 200:1 Is; The particle size distribution of the nanoparticles is bimodal or multimodal; Binders include multifunctional fluorinated (meth)acrylic compounds; Polyfunctional fluorinated (meth)acrylic compounds contain cyclic siloxane units.

Example

In the following examples, specific embodiments of the present invention are illustrated, but the present invention is not limited to these embodiments. All "parts" and "percents" are by mass unless otherwise specified.

Assessment Methods

The properties of the hard coat of the present invention were evaluated according to the following method. A hard coat precursor was applied to a substrate and a hard coat was formed by irradiating the precursor with ultraviolet rays. The hard coat was evaluated while being supported on the substrate.

1. Pencil hardness

The pencil hardness of the surface of the hard coat formed on the substrate was determined using a 750 g weight according to JIS K5600-5-4 (1999).

2. Optical properties

The turbidity of the hard coat was measured using an NDH-5000W turbidimeter (obtained from Nippon Denshoku Industries Co., Ltd.) according to JIS K 7136 (2000).

3. Contact angle

The water contact angle on the surface of the hard coat was measured using a contact angle measuring instrument (obtained from Kyowa Kaimen Kagaku Co., Ltd. under the product name "DROPMASTER FACE") using the Cecil drop method. It was measured by (Sessile Drop method). For static measurements, the volume of the liquid droplet was set to 4 μL. The value of the water contact angle was calculated from the average of five measurements.

4. Ink repellency test

The appearance was visually observed after drawing a single straight line on the hard coat using a permanent marker (Maki (black), obtained from Zebra Co., Ltd.). A sample that repelled ink and did not form a line was evaluated as excellent, and a sample that formed a line without repelling ink was evaluated as defective.

5. Wear resistance test

The scratch resistance of the hard coat was evaluated by measuring the optical properties and water contact angle after the abrasion resistance test. In the cloth abrasion resistance test, a JIS test cloth (obtained from the Japanese Industrial Standards Committee) having a width of 32 mm was used under a load of 500 g, and in the bristle wear resistance test, 32 of #0000 bristles mm square pieces were used under a load of 1 kg. 200 cycles of abrasion were applied to the hard coat surface at a rate of 60 cycles per minute, of 85 mm stroke. Fig. 2 shows a schematic diagram of a wear resistance testing apparatus 60 (obtained from Imoto Machinery Co., Ltd., IMC-157C rubbing tester, Imoto Machinery Co., Ltd.). Here, the sample 10 is fixed to the top of the stage 61, and the load of the weight 63 is applied to the cloth or bristles 64 through a stylus 62, and the stage 61 is moved back and forth. By rubbing the surface of the sample. The abrasion resistance test simulates scratching caused by wiping and washing.

[Table 1]

Preparation of surface-modified silica sol (sol 1)

A surface-modified silica sol ("Sol 1") was prepared as follows. First, 5.95 g of Silquest A174 and 0.5 g of ProStab were added to a mixture of 400 g of Nalco 2329 and 450 g of 1-methoxy-2-propanol in a glass vial, and stirred at room temperature for 10 minutes. The glass vial was sealed and placed in an oven at 80° C. for 16 hours. Water was removed from the resulting solution using a rotary evaporator until the solid content of the solution reached nearly 45% by mass at 60°C. 200 g of 1-methoxy-2-propanol was added to the resulting solution, and the remaining water was removed at 60° C. using a rotary evaporator. The rear half of the above steps was repeated twice to further remove water from the solution. Finally, the surface conditioning, the average particle size of 75 nm to 45 mass% by the addition of all the SiO ₂ nanoparticles 1-methoxy-2-propanol to a concentration of - SiO ₂ containing the modified SiO ₂ nanoparticles A sol (hereinafter referred to as "sol 1") was obtained.

Preparation of surface-modified silica sol (sol 2)

A surface-modified silica sol ("Sol 2") was prepared as follows. The modification was carried out using the same method as for Sol 1, except that 400 g of Nalco 2327, 25.25 g of Silquest A174, and 0.5 g of ProStab were used, and surface-modification with an average particle size of 20 nm. the SiO ₂ nanoparticles (referred to below becomes, "sol 2") SiO ₂ sol containing 45 mass% was obtained.

Preparation of hard coat precursor (HC-1)

First, 11.34 g of Sol 1, 5.88 g of Sol 2, 2.25 g of Ebecryl 4858, and 0.25 g of SR340 were mixed. Next, 0.20 of Irgacure 2959 was added to the mixture as an optical polymerization initiator, and 0.001 g of BYK-UV3500 was added to the mixture as a leveling agent. Thereafter, the mixture was adjusted so that the solid content was 50% by mass by adding 1-methoxy-2-propanol, thereby preparing a hard coat precursor HC-1.

Preparation of hard coat precursor (HC-2)

First, 11.34 g of Sol 1, 5.88 g of Sol 2, 2.25 g of Ebecryl 4858, and 0.25 g of SR340 were mixed. Next, 0.17 g of HFPO urethane acrylate was added to the mixture as an antifouling agent, 0.1 g of Irgacure 2959 was added to the mixture as an optical polymerization initiator, and 0.001 g of BYK-UV3500 was added to the mixture as a leveling agent. Added. Thereafter, the mixture was adjusted so that the solid content was 50% by mass by adding 1-methoxy-2-propanol, thereby preparing a hard coat precursor HC-2. HFPO urethane acrylate is a monofunctional fluorinated (meth)acrylic compound.

Preparation of hard coat precursors (HC-3 to HC-8)

Hard coat precursors HC-3 to HC-8 were prepared in the same manner as HC-2 using the formulations shown in Table 2. Kaylard UX-5000 was used as an acrylate oligomer in HC-6 to HC-8, and KY-1203 was used as a polyfunctional (meth)acrylic compound (antifouling agent) in HC-4, HC-5, and HC-8. Used. The composition of HC-1 to HC-8 is illustrated in Table 2.

[Table 2]

Example 1

PMMA substrate (Acrylite L-001, 100 × 53 × 2 mm, obtained from Mitsubishi Rayon Co., Ltd.) of a stainless steel table equipped with a level. It was fixed on the top. The hard coat precursor HC-4 was applied to the PMMA substrate using a #16 Meyer rod, and dried at 60° C. for 5 minutes. Next, using an H-valve (DRS model) manufactured by Fusion UV System Inc., ultraviolet rays were irradiated 10 times on the coating surface at a line speed of 13 m/min in a nitrogen atmosphere ( Irradiance: approximately 1400 mJ/ ² ). The thickness of the hard coat was approximately 10 μm. In this way, the hard coat of Example 1 was formed on the PMMA substrate.

Examples 2 and 3 and Comparative Examples 1 to 5

Hard coat precursors HC-1 to HC-3 and HC-5 to HC-8 were used to form a hard coat on the PMMA substrate in the same manner as in Example 1. The evaluation results of these hard coats are illustrated in Tables 3 and 4.

[Table 3]

[Table 4]

As shown in Table 3, a hard coat containing a fluorinated (meth)acrylic compound as an antifouling agent (Example 1 and Example 2: KY-1203, Comparative Example 2 and Comparative Example 3: HFPO urethane acrylate) is fluorine It showed a pencil hardness of 8H, which is equivalent to that of the hard coat (Comparative Example 1) that does not contain a chemical (meth)acrylic compound. The addition of an appropriate amount of the fluorinated (meth)acrylic compound did not affect the pencil hardness of the hard coat. The water contact angle increased when the fluorinated (meth)acrylic compound was added. HC-4 (Example 1) and HC-5 (Example 2) showed good ink repellency even after the cloth abrasion resistance test. On the other hand, the ink repellency became poor after the cloth abrasion resistance test in HC-3 (Comparative Example 3), where the amount of HFPO urethane acrylate used as an antifouling agent was increased.

Table 4 shows the results of performing the bristle wear resistance test in addition to the cloth wear resistance test. The water contact angle and ink repellency were compared before and after the cloth abrasion resistance test, and the water contact angle, ink repellency and optical properties were compared before and after the bristle abrasion resistance test. HC-7 (Comparative Example 5) and HC-8 (Example 3) showed good ink repellency at the start of and after the cloth abrasion resistance test as well as a water contact angle exceeding 100 degrees. The hard coat of Example 2 containing UX-5000, a polyfunctional acrylate having a plurality of acrylate groups as the urethane acrylate oligomer, had higher scratch resistance than the hard coat of Example 3 containing Ebecryl 4858.

Bristle wear resistance was improved as a result of the addition of a fluorinated (meth)acrylic compound. After the bristle wear resistance test, the rate of change (Δ turbidity) of the turbidity values of HC-7 (Comparative Example 5) and HC-8 (Example 3) was less than 0.1%. Due to the fluorinated (meth)acrylic compound, the bristle wear resistance of the hard coat was improved and the friction coefficient of the hard coat surface was decreased. In particular, HC-8 (Example 8 containing KY-1203) had excellent scratch resistance and showed high durability with respect to antifouling properties. The ink repellency of HC-8 did not change even after the bristle wear resistance test. The hard coat containing the polyfunctional fluorinated (meth)acrylic compound with siloxane units showed higher antifouling durability than those containing the monofunctional fluorinated (meth)acrylic compound.

Explanation of sign

60: wear resistance test device

61: stage

62: stylus

63: weight body

64: cloth or bristle

Claims (8)

A hard coat comprising a mixture of nanoparticles and a binder,
The nanoparticles constitute 40 to 95% by mass of the total mass of the hard coat;
10 to 50% by mass of the nanoparticles have an average particle size in the range of 2 to 200 nm;
50 to 90% by mass of the nanoparticles have an average particle size in the range of 60 to 400 nm;
The ratio of the average particle size of the nanoparticles having an average particle size in the range of 60 to 400 nm to the average particle size of the nanoparticles having an average particle size in the range of 2 to 200 nm is 2:1 to 200: Within the range of 1;
The particle size distribution of the nanoparticles is bimodal or multimodal;
The binder comprises a multifunctional fluorinated (meth)acrylic compound, a reaction product thereof, or a combination thereof; The multifunctional fluorinated (meth)acrylic compound contains cyclic siloxane units,
The hard coat
Nanoparticles having an average particle size in the range of 2 to 200 nm of 10 to 50% by mass based on the total mass of the nanoparticles, an average particle in the range of 60 to 400 nm of 50 to 90% by mass of the total mass of the nanoparticles Combining the sized nanoparticles, and a binder to obtain a hard coat precursor, and
Coating the precursor on a substrate to form a hard coat
Produced by a method comprising,
Hard coat. The method of claim 1,
The nanoparticles are silica nanoparticles, and the multifunctional fluorinated (meth)acrylic compound contains siloxane units. As a hard coat precursor comprising a nanoparticle mixture and a binder,
The nanoparticles constitute 40 to 95% by mass of the total mass of the nanoparticles and the binder;
10 to 50% by mass of the nanoparticles have an average particle size in the range of 2 to 200 nm;
50 to 90% by mass of the nanoparticles have an average particle size in the range of 60 to 400 nm;
The ratio of the average particle size of the nanoparticles having an average particle size in the range of 60 to 400 nm to the average particle size of the nanoparticles having an average particle size in the range of 2 to 200 nm is 2:1 to 200: Within the range of 1; The particle size distribution of the nanoparticles is bimodal or multimodal;
The binder comprises a multifunctional fluorinated (meth)acrylic compound; The multifunctional fluorinated (meth)acrylic compound contains cyclic siloxane units,
The hard coat precursor is a nanoparticle having an average particle size in the range of 2 to 200 nm of 10 to 50 mass% based on the total mass of the nanoparticles, 60 to 400 nm of 50 to 90 mass% based on the total mass of the nanoparticles Prepared by a method comprising the step of combining nanoparticles having an average particle size within the range of, and a binder to obtain a hard coat precursor,
Hard coat precursor. delete delete delete delete delete

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