HK1209448B - Anti-smudge hard coat and anti-smudge hard coat precursor - Google Patents

Description

Antifouling hard coat and antifouling hard coat precursor

Cross Reference to Related Applications

This patent application claims priority from japanese patent application JP 2012-170999 filed on 8/1/2012, the disclosure of which is incorporated by reference in its entirety.

Technical Field

The present disclosure relates to antifouling hardcoats and antifouling hardcoat precursors.

Background

The hard coating layer is used to protect the surface of various hard and flexible materials. The hard coat layer is required to have excellent scratch resistance, impact resistance, and the like, and to have optical characteristics in the case of a transparent material. Furthermore, there is a strong need for hardcoat surfaces that have antifouling properties.

Comprising SiO modified by a photocuring silane coupling agent₂Nanoparticle hardcoat materials are described in U.S. Pat. Nos. 5104929 and 7074463.

Hardcoat materials having antifouling properties and having an easily cleanable surface obtained by curing a polymerizable composition comprising a fluorine compound having hexafluoropropylene oxide sites are described in U.S. patent 7718264 and U.S. patent application publication 2008/0124555.

As the surface of the hard coat layer wears, the antifouling property of the hard coat layer tends to deteriorate. Therefore, there is still a need to further improve the durability of antifouling hardcoats. Accordingly, it is an object of the present disclosure to provide a hard coating and a hard coating precursor having antifouling properties of excellent scratch resistance and durability.

Disclosure of Invention

One embodiment of the present disclosure provides a hard coat layer comprising a nanoparticle mixture and a binder, wherein the nanoparticles constitute 40 to 95 mass% of the entire mass of the hard coat layer; 10 to 50 mass% of the nanoparticles have an average particle size in the range of 2 to 200 nm; 50 to 90 mass% of the nanoparticles have an average particle size in the range of 60 to 400 nm; a ratio of an average particle size of nanoparticles having an average particle size in a range of 60nm to 400nm to an average particle size of nanoparticles having an average particle size in a range of 2nm to 200nm is in a range of 2:1 to 200: 1; and the binder comprises a multifunctional fluorinated (meth) acrylic compound, a reaction product thereof, or a combination thereof.

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

The antifouling hard coat layer of the present disclosure filled with high concentration of nanoparticles exhibits both excellent scratch resistance and impact resistance while maintaining optical transparency. In addition, since the binder contains a polyfunctional fluorinated (meth) acrylic compound, a reaction product thereof, or a combination thereof, adhesion of fingerprints, grease, dust, stains, and the like can be prevented or a hard coat layer can be easily washed in the case of such adhesion, and durability of antifouling property can also be increased. Further, the antifouling hardcoat layer can be formed using the antifouling hardcoat layer precursor of the present disclosure.

The above description should not be taken as a disclosure of all embodiments of the invention or all advantages of the invention.

Drawings

Fig. 1 is a graph showing the results of a simulation between the mass ratio and the filling rate of a small particle group and a large particle group for several combinations of particle sizes (small particle group/large particle group).

Fig. 2 is a schematic diagram of a pattern of the abrasion resistance test apparatus used in the examples.

Detailed Description

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

In the present disclosure, "(meth) acrylic" means "acrylic or methacrylic", and "(meth) acrylate" means "acrylate or methacrylate".

The hardcoat of one embodiment of the disclosure comprises a nanoparticle mixture and a binder, and the binder comprises a multifunctional fluorinated (meth) acrylic compound, a reaction product thereof, or a combination thereof.

Examples of representative binders contained in the hard coat layer include resins obtained by polymerizing curable monomers and/or curable oligomers and resins obtained by polymerizing sol-gel glass. More specific examples include acrylic resins, polyurethane 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, and a mixture of two or more curable monomers, a mixture of two or more curable oligomers, or a mixture of one or two or more curable monomers and one or two or more curable oligomers may be used. In several embodiments, examples of resins include dipentaerythritol pentaacrylate (e.g., Sartomer Company, Exton, PA, available under the product name "SR 399" from Sartomer Company, Exton, axton, PA), pentaerythritol triacrylate isophorone diisocyanate (IPDI) (e.g., Nippon Kayaku co, ltd., Tokyo Japan under the product name "UX-5000"), urethane acrylates (e.g., Nippon Synthetic Chemical Industry co., ltd., Tokyo Japan under the product name "UV 1700B" and "UB 6300B"), trimethylhydroxy diisocyanate/hydroxyethyl acrylate (TMHDI/HEA, e.g., dazo polyester Company, available under the product name "ecrryl 4858" from Tokyo cellulose co., Japan, ltd., Tokyo Japan)), polyethylene oxide (PEO) modified bis-a-diacrylate (e.g., a product name "R551" available from Nippon Kayaku co., ltd., Tokyo Japan), PEO modified bis-a-epoxyacrylate (e.g., a product name "3002M" available from kyo Chemical co., Osaka), a silane-based UV curable resin (e.g., a product name "SK 501M" available from Nagase mtex Corporation, Osaka, Japan), and 2-phenoxyethyl methacrylate (e.g., a product name "SR 340" available from sartome company, sartany, and a polymer mixture of these compounds. For example, when 2-phenoxyethyl methacrylate is used in the range of about 1.0 to 20 mass%, improvement in adhesion to polycarbonate is observed. When a bifunctional resin (e.g., PEO-modified bis-a-diacrylate "R551") and trimethylhydroxydiisocyanate/hydroxyethyl acrylate (TMHDI/HEA) (e.g., available under the product name "EBECRYL 4858" from celluloid-cyanotex corporation, Tokyo, Japan), were used, an improvement in the hardcoat in terms of hardness, impact resistance, and flexibility was observed.

The amount of binder in the hardcoat layer is typically about 5 to 60 mass%, and, in several embodiments, about 10 to 40 mass% or about 15 to 30 mass% of the total mass of the antireflective hardcoat layer. According to the present disclosure, a hard coat layer having a relatively small amount of binder may be formed.

The hard coat layer may also be cured with another curable monomer or curable oligomer, if necessary. Representative examples of curable monomers or curable oligomers include multifunctional (meth) acrylic monomers and multifunctional (meth) acrylic oligomers selected from the group consisting of: (a) compounds having two (meth) acrylic groups such as 1, 3-butanediol diacrylate, 1, 4-butanediol diacrylate, 1, 6-hexanediol monoacrylate, ethylene glycol diacrylate, alkoxylated aliphatic diacrylates, alkoxylated cyclohexanedimethanol diacrylates, alkoxylated hexanediol diacrylates, alkoxylated neopentyl glycol diacrylates, caprolactone-modified neopentyl glycol hydroxypivalate diacrylate, cyclohexanedimethanol diacrylate, diethylene glycol diacrylate, dipropylene glycol diacrylate, ethoxylated (10) bisphenol-A-diacrylate, ethoxylated (3) bisphenol-A-diacrylate, ethylene glycol diacrylate, ethylene, Ethoxylated (30) bisphenol-A diacrylate, ethoxylated (4) bisphenol-A diacrylate, hydroxypivalaldehyde modified trimethylolpropane diacrylate, neopentyl glycol diacrylate, polyethylene glycol (200) diacrylate, polyethylene glycol (400) diacrylate, polyethylene glycol (600) diacrylate, 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, trimethylolpropane triacrylate, ethoxylated triacrylates (e.g., ethoxylated (3) trimethylolpropane triacrylate, ethoxylated (6) trimethylolpropane triacrylate, ethoxylated (9) trimethylolpropane triacrylate, ethoxylated (20) trimethylolpropane triacrylate, etc.), pentaerythritol triacrylate, propoxylated triacrylates (e.g., propoxylated (3) glyceryl triacrylate, propoxylated (5.5) glyceryl triacrylate, propoxylated (3) trimethylolpropane triacrylate, propoxylated (6) trimethylolpropane triacrylate, and the like), trimethylolpropane triacrylate, tris- (2-hydroxyethyl) isocyanurate triacrylate, and the like; (c) compounds having four (meth) acrylic groups such as ditrimethylolpropane tetraacrylate, dipentaerythritol pentaacrylate, ethoxylated (4) pentaerythritol tetraacrylate, caprolactone-modified dipentaerythritol hexaacrylate, and the like; (d) oligomer (meth) acrylic compounds such as urethane acrylates, polyester acrylates, epoxy acrylates, and the like; polyacrylamide analogues of the above; and combinations thereof. Such compounds are commercially available, and at least several of these compounds are available from Sartomer Company (Sartomer Company), UCB chemicals of sammaca, georgia (ucbcchemicals Corporation, Smyrna, GA), aldrich chemicals of Milwaukee, wisconsin, and the like. Examples of other useful (meth) acrylates include poly (meth) acrylates comprising hydantoin moieties, such as disclosed in U.S. patent 4262072.

Preferred curable monomers or curable oligomers contain at least three (meth) acrylic groups. Preferred commercially available curable monomers or curable oligomers include those available from Sartomer Company (Sartomer Company), such as trimethylolpropane triacrylate (TMPTA) (product name: "SR 351"), pentaerythritol tri/tetraacrylate (PETA) (product names: "SR 444" and "SR 295"), and dipentaerythritol pentaacrylate (product name: "SR 399"). In addition, mixtures of multifunctional (meth) acrylates and monofunctional (meth) acrylates may also be used, such as a mixture of PETA and 2-phenoxyethyl acrylate (PEA).

The mixture of nanoparticles included in the hard coat layer constitutes about 40 to 95 mass% of the entire mass of the hard coat layer, and in several embodiments, about 60 to 90 mass% or about 70 to 85 mass% of the entire mass of the hard coat layer. The nanoparticle mixture includes about 10 to 50 mass% of nanoparticles having an average particle size in a range of about 2 to 200nm (hereinafter referred to as a small particle group or a first nanoparticle group) and about 50 to 90 mass% of nanoparticles having an average particle size in a range of about 60 to 400nm (hereinafter referred to as a large particle group or a second nanoparticle group). For example, the nanoparticle mixture may be obtained by mixing a first nanoparticle group having an average particle size of about 2nm to 200nm and a second nanoparticle group having an average particle size of about 60nm to 400nm in a mass ratio of about 10:90 to 50: 50.

The average particle size of the nanoparticles can be measured with a Transmission Electron Microscope (TEM) using techniques commonly used in the art. In the measurement of the average particle size of nanoparticles, sol samples for TEM images can be prepared by dropping sol samples into 400-mesh copper TEM grids with ultra-thin carbon substrates (available from california) on the upper surface of the mesh-lace-like carbonTedepera corporation of latin (Ted Pella inc., Redding, CA)). Some droplets may be removed by contacting the droplets with filter paper and the side or bottom portions of the grid. The remaining sol solvent can be removed by heating or allowing the solution to remain at room temperature. This allows the particles to remain on the ultra-thin carbon substrate and be imaged with minimal interference from the substrate. Next, TEM images may be recorded at many locations across the entire grid. Enough images were recorded to allow measurement of particle sizes of 500 to 1000 particles. Next, the average particle size of the nanoparticles may be calculated based on the particle size measurements of each sample. The TEM image may be taken using a high resolution transmission electron microscope (using LaB)₆The source electrode) (available under the product name "Hitachi H-9000" from Hitachi High Technologies Corporation) operating at 300KV the image may be recorded using a camera (available under the product name "GATAN ULTRASCAN CCD" from Pluisonon Gntan, Calif., Gatan Inc., Pleasanton, Calif.) such as a model 895, 2k × 2k chip.

The nanoparticles are typically inorganic particles. Examples of the inorganic particles include inorganic oxides such as aluminum oxide, zinc oxide, antimony oxide, silicon dioxide (SiO )₂) Zirconia, titania, ferrites, and the like, and mixtures thereof, or mixed oxides thereof; metal vanadates, metal tungstates, metal phosphates, metal nitrates, metal sulfates, metal carbides, and the like. Inorganic oxide sols can be used as the inorganic oxide nanoparticles. As the silica nanoparticles, for example, a silica sol may be used, wherein the silica sol is obtained using liquid glass (sodium silicate solution) as a raw material. Depending on the manufacturing conditions, the silica sol obtained from the liquid glass can have a very narrow particle size distribution; therefore, when the silica sol is used, a hard coating layer having desired characteristics can be obtained by more precisely controlling the filling rate of the nanoparticles in the hard coating layer.

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

The nanoparticle mixture comprises a particle size distribution of at least two different types of nanoparticles. The particle size distribution of the nanoparticle mixture may exhibit a bimodal or multimodal peak at the average particle size of the small particle group and the average particle size of the large particle group. The nanoparticles may be the same or different from each other (e.g., compositionally surface modified or not surface modified) except for the particle size distribution. In several embodiments, the ratio of the average particle size of the nanoparticles having an average particle size in the range of about 2nm to 200nm to the average particle size of the nanoparticles having an average particle size in the range of about 60nm to 400nm is in the range of 2:1 to 200:1 and, in several embodiments, in the range of 2.5:1 to 100:1 or 2.5:1 to 25: 1. Examples of preferred average particle size combinations include combinations of 5nm/190nm, 5nm/75nm, 20nm/190nm, 5nm/20nm, 20nm/75nm, 75nm/190nm, and 5nm/20nm/190 nm. By using a mixture of nanoparticles of different sizes, the hard coating can be filled with a large number of nanoparticles to increase the hardness of the hard coating.

In addition, the transmittance (haze, etc.) and hardness can be varied by selecting, for example, the type, amount, size, and ratio of nanoparticles. In several embodiments, a hard coating having both a desired transmittance and hardness may be obtained.

The mass ratio (%) of the small particle group to the large particle group may be selected according to the particle size used or the combination of the particle sizes used. The preferred mass ratio can be selected by using software obtained under the product name "CALVOLD 2" according to the particle size used or the particle size combination used, and can be selected based on simulations between the mass ratio and the filling rate of the small-particle group to the large-particle group for the particle size combination (small-particle group/large-particle group), for example (see also "Verification of a Model for estimating the Void Fraction in a Three-Component Randomly filled base" (Verification of a Model for estimating the Void Fraction), m.suzuki and t.oshima: Powder technology (Powder technology.), 43, 147-. The simulation results are shown in fig. 1. According to the simulation, the mass ratio (small particle group: large particle group) for the combination of 5nm/190nm was about 45:55 to 13:87 or about 40:60 to 15: 85. The mass ratio for the combination of 5nm/75nm is preferably about 45:55 to 10:90 or about 35:65 to 15: 85. The mass ratio for the combination of 20nm/190nm is preferably about 45:55 to 10: 90. The mass ratio for the combination of 5nm/20nm is preferably about 50:50 to 20: 80. The mass ratio for the combination of 20nm/75nm is preferably about 50:50 to 22: 78. The mass ratio for the combination of 75nm/190nm is preferably about 50:50 to 27: 73.

In several embodiments, the use of a combination of preferred particle sizes and nanoparticles makes it possible to increase the amount of nanoparticles filling the hard coating and to adjust the transmittance and hardness of the resulting hard coating.

The thickness of the hard coat layer is typically in the range of about 80nm to 30 μm (in several embodiments, about 200nm to 20 μm or about 1 μm to 10 μm), however, even when the thickness deviates from these ranges, the hard coat layer may sometimes be effectively used. The use of a mixture of nanoparticles of different sizes sometimes makes it possible to obtain hard coatings with greater thickness and higher hardness.

If necessary, the surface of the nanoparticles may be modified using a surface treatment agent. The surface treatment agent typically has a first end bonded to the surface of the particle (by covalent, ionic, or strong physisorption) and a second end that imparts compatibility of the particle with the resin and/or reaction with the resin during curing. Examples of surface treatment agents include alcohols, amines, carboxylic acids, sulfonic acids, phosphonic acids, silanes, and titanates. The preferred type of surface treatment agent is determined in part by the chemistry of the nanoparticle surface. Silanes are preferred when silica or another siliceous filler is used as the nanoparticles. For metal oxides, silanes and carboxylic acids are preferred. The surface modification may be performed before, during or after mixing with the curable monomer or curable oligomer. When a silane is used, the reaction between the silane and the surface of the nanoparticles is preferably carried out before mixing with the curable monomer or curable oligomer. The required amount of surface treatment agent is determined by several factors such as the particle size and type of nanoparticles and the molecular weight and type of surface treatment agent. It is generally preferred to deposit a layer of surface treatment agent onto the surface of the particles. The desired deposition procedure or reaction conditions are also determined by the surface treatment agent used. When silane is used, the surface treatment is preferably performed under acidic or basic conditions at high temperature for about 1 to 24 hours. In the case of surface treatment agents such as carboxylic acids, high temperatures or long periods of time are generally not necessary.

Representative examples of surface treatments include compounds such as isooctyltrimethoxysilane, polyalkylene oxide alkoxysilanes (e.g., obtained under the product designation "SILQUEST A1230" from Momentive Specialty Chemicals Inc., Columbus, OH), N- (3-triethoxysilylpropyl) methoxyethoxyethylethyl carbamate, 3- (methacryloyloxy) propyltrimethoxysilane (e.g., obtained under the product designation "SILQUEST A174" from Alfa Aesar, WardHill, MA, Wodel, Mass.), 3- (acryloyloxy) propyltrimethoxysilane, 3- (methacryloyloxy) propyltriethoxysilane, 3- (methacryloyloxy) propylmethyldimethoxysilane, 3- (acryloyloxy) propylmethyldimethoxysilane, 3- (methacryloyloxy) propyldimethylethoxysilane, vinyldimethylethoxysilane, phenyltrimethoxysilane, n-octyltrimethoxysilane, dodecyltrimethoxysilane, octadecyltrimethoxysilane, propyltrimethoxysilane, hexyltrimethoxysilane, vinylmethyldiacetoxysilane, vinylmethyldiethoxysilane, vinyltriacetoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, vinyltrimethoxysilane, vinyltriphenoxysilane, vinyltri (t-butoxy) silane, vinyltri (isobutoxy) silane, vinyltriisopropenoxysilane, vinyltri- (2-methoxyethoxy) silane, styrylethyltrimethoxysilane, vinyldimethylethoxysilane, vinyltriethoxysilane, mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, acrylic acid, methacrylic acid, oleic acid, stearic acid, dodecanoic acid, 2- [2- (2-methoxyethoxy) ethoxy ] acetic acid (MEEAA), beta-carboxyethyl acrylate, 2- (2-methoxyethoxy) acetic acid, and methoxyphenylacetic acid and mixtures thereof.

The binder of the antifouling hardcoats of the present disclosure comprises a multifunctional fluorinated (meth) acrylic compound, reaction products thereof, or combinations thereof that provides antifouling properties to the hardcoat surface and improves ease of laundering (e.g., anti-fingerprint, oil-repellency, dust-repellency, and/or antifouling function). The multifunctional fluorinated (meth) acrylic compound has multiple (meth) acrylic groups and thus may react with a curable monomer or curable oligomer as a cross-linking agent or may non-covalently interact with functional groups contained in the binder at multiple sites. Therefore, the durability of the antifouling property can be increased. When a polyfunctional fluorinated (meth) acrylic compound is used, scratch resistance can also be increased by reducing the friction coefficient of the hard coat surface. When a polyfunctional fluorinated (meth) acrylic compound having three or more (meth) acrylic groups is used, the durability of the antifouling property can also be increased.

Since the perfluoroether group provides a hard coat layer having excellent antifouling properties, the polyfunctional fluorinated (meth) acrylic compound is preferably a perfluoroether compound having two or more (meth) acrylic groups.

For example, polyfunctional perfluoroether (meth) acrylates described in Japanese unexamined patent application publication No. 2008-538195 and Japanese unexamined patent application publication No. 2008-527090 are useful as perfluoroether compounds having two or more (meth) acrylic groups. Specific examples of such multifunctional perfluoroether (meth) acrylates include:

HFPO-C(O)N(H)CH(CH₂OC(O)CH＝CH₂)₂；

HFPO-C(O)N(H)C(CH₂CH₃)(CH₂OC(O)CH＝CH₂)₂；

HFPO-C(O)NHC(CH₂OC(O)CH＝CH₂)₃；

HFPO-C(O)N(CH₂CH₂OC(O)CH＝CH₂)₂；

HFPO-C(O)NHCH₂CH₂N(C(O)CH＝CH₂)CH₂OC(O)CH＝CH₂；

HFPO-C(O)NHCH(CH₂OC(O)CH＝CH₂)₂；

HFPO-C(O)NHC(CH₃)(CH₂OC(O)CH＝CH₂)₂；

HFPO-C(O)NHC(CH₂CH₃)(CH₂OC(O)CH＝CH₂)₂；

HFPO-C(O)NHCH₂CH(OC(O)CH＝CH₂)CH₂OC(O)CH＝CH₂；

HFPO-C(O)NHCH₂CH₂CH₂N(CH₂CH₂OC(O)CH＝CH₂)₂；

HFPO-C(O)OCH₂C(CH₂OC(O)CH＝CH₂)₃；

HFPO-C(O)NH(CH₂CH₂N(C(O)CH＝CH₂))₄CH₂CH₂NC(O)-HFPO；

CH₂＝CHC(O)OCH₂CH(OC(O)HFPO)CH₂OCH₂CH(OH)CH₂OCH₂CH(OC(O)HFPO)CH₂OCOCH＝CH₂；

HFPO-CH₂O-CH₂CH(OC(O)CH＝CH₂)CH₂OC(O)CH＝CH₂(ii) a And so on.

In this disclosure, HFPO isIs indicated by F (CF (CF3) CF₂O)_nCF(CF₃) A perfluoroether site represented by- (n is 2 to 15) and a compound containing the perfluoroether site.

The above-mentioned polyfunctional perfluoropolyether (meth) acrylate can be synthesized by the following steps: for example, the first step of reacting a poly (hexafluoropropylene oxide) ester such as HFPO-C (O) OCH₃Or poly (hexafluoropropylene oxide) acid halide: HFPO-c (o) F with a material comprising at least three alcohol or primary or secondary amino groups to produce HFPO-esters with HFPO-amide polyols or polyamines, HFPO-ester polyols or polyamines, HFPO-amides or mixed amine and alcohol groups, and a second step of (meth) acrylating the alcohol groups and/or amine groups with (meth) acrylhalide, (meth) acrylic anhydride or (meth) acrylic acid. Alternatively, the multifunctional perfluoropolyether (meth) acrylates can be synthesized using Michael-type addition reactions of reactive perfluoroethers, such as HFPO-C (O) N (H) CH₂CH₂CH₂N(H)CH₃And an adduct of trimethylolpropane triacrylate (TMPTA) and poly (meth) acrylate.

The preferred polyfunctional fluorinated (meth) acrylic compound is one in which the perfluoroether moiety is divalent and the (meth) acrylic group is bonded to both terminals directly or through other groups or bonds (ether bond, ester bond, amide bond, urethane bond, etc.). While not being bound by any particular theory, it is believed that the compound forms a strong bond with the hard coat layer so as to improve durability of the antifouling property, and perfluoroether sites between (meth) acrylic groups migrate to the surface of the hard coat layer so as to be easily oriented in the planar direction. Therefore, antifouling properties can be sufficiently exhibited.

The multifunctional fluorinated (meth) acrylic compound may comprise siloxane units. When the nanoparticles are inorganic oxides, the polyfunctional fluorinated (meth) acrylic compound containing siloxane units is more strongly bound to the hard coat layer not only by the reaction between the (meth) acrylic group and the curable monomer or curable oligomer but also by the interaction between the siloxane bond and the nanoparticles, which is considered to further increase the durability of the antifouling property. The nanoparticles are preferably silica nanoparticles that are chemically similar to siloxane bonds and have a high affinity for siloxane bonds.

The polyfunctional fluorinated (meth) acrylic compound containing a siloxane unit can be synthesized, for example, by adding a (hydrosilation) perfluoropolyether compound having one or two or more unsaturated vinyl groups to a linear or cyclic oligosiloxane or a polysiloxane (hydrosiloxane) containing three or more Si-H bonds in the presence of a platinum catalyst or the like in a volume of less than one equivalent relative to the Si-H bonds, similarly adding a (hydrosilation) unsaturated vinyl compound containing a hydroxyl group to the remaining Si-H bonds in the presence of a platinum catalyst or the like, and then reacting the hydroxyl group with an epoxy (meth) acrylate, a urethane (meth) acrylate, or the like. The partial molecular weight of the perfluoroether site calculated from the chemical formula may be 500 to 30,000.

In order to sufficiently exhibit the antifouling property imparted by the fluorinated site, the siloxane unit is preferably a cyclic siloxane unit derived from tetramethylcyclotetrasiloxane, pentamethylcyclopentasiloxane, or the like. The number of silicon atoms constituting the cyclic siloxane unit is preferably 3 to 7.

Examples of the polyfunctional fluorinated (meth) acrylic compound containing a siloxane unit are perfluoropolyether compounds having two or more (meth) acrylic groups described in, for example, japanese unexamined patent application publication 2010-285501. For example, the compounds of formula (19) and formula (21) in this publication have the structures: wherein the cyclic siloxane has four groups each bonded to a divalent perfluoropolyether group: -CF₂(OCF₂CF₂)_p(OCF₂)_qOCF₂Two terminal silicon atoms of- (p/q ≈ 0.9, p + q ≈ 45), and three acryloyloxy groups bonded to each of these cyclic siloxanes through a urethane group, which are suitable for the antifouling hardcoat of the present disclosure.

When the polyfunctional fluorinated (meth) acrylic compounds and their reaction products are considered to be polyfunctional fluorinated (meth) acrylic compounds tailored to the reaction products, the compounds and reaction products are contained in the binder, for example, in a range of about 0.01 to 20 parts by mass (in several embodiments, about 0.1 to 10 parts by mass or about 0.2 to 5 parts by mass) relative to a total of 100 parts by mass of the nanoparticles, curable monomers, and curable oligomers.

The binder of the hard coat layer may further contain known additives such as an ultraviolet absorber, a defogging agent, a leveling agent, an ultraviolet reflecting agent, an antistatic agent, etc., or another chemical providing a cleaning promoting function as needed.

In some embodiments, the uv absorber is included in the binder of the hardcoat. The ultraviolet absorber may be mixed with the curable monomer or curable oligomer. Known agents may be used as ultraviolet light absorbers. For example, ultraviolet absorbers such as benzophenone absorbers (e.g., from BASF AG under the product name "Uvinul 3050"), benzotriazole absorbers (e.g., from BASF AG under the product name "Tinuvin 928"), triazine absorbers (e.g., from BASF AG under the product name "Tinuvin 1577"), salicylate absorbers, diphenylacrylate absorbers, and cyanoacrylate absorbers and Hindered Amine Light Stabilizers (HALS) (e.g., from BASF AG under the product name "Tinuvin 292") may be used. By using the known ultraviolet absorber and hindered amine light stabilizer in combination, the ultraviolet absorptivity of the hard coat layer can be further increased as compared with the use of the respective components alone.

The amount of the ultraviolet absorber added may be, for example, in the range of about 0.01 to 20 parts by mass, (in several embodiments, about 0.1 to 15 parts by mass or about 0.2 to 10 parts by mass) relative to 100 parts by mass of the total of the nanoparticles, the curable monomer, and the curable oligomer. In some embodiments, a hardcoat layer comprising an ultraviolet absorber can achieve less than 3% ultraviolet transmission.

In some embodiments, the dehazer is included in the binder of the hardcoat. The dehazer can be mixed with a curable monomer or curable oligomer. Anionic, cationic, nonionic or amphoteric surfactants can be used as the dehazing agent, and examples thereof include sorbitan surfactants such as sorbitan monostearate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monobehenate, and esters of sorbitan, alkylene glycol condensates and fatty acids; a glycerol surfactant such as glycerol monopalmitate, glycerol monostearate, glycerol monolaurate, diglycerol monopalmitate, glycerol dipalmitate, glycerol distearate, glycerol monopalmitate/monostearate, triglycerol distearate, or alkylene oxide adducts thereof; polyethylene glycol surfactants such as polyethylene glycol monostearate, polyethylene glycol glycerol monopalmitate, and polyethylene glycol alkylphenyl ether; trimethylolpropane surfactants such as trimethylolpropane monostearate; pentaerythritol surfactants such as pentaerythritol monopalmitate and pentaerythritol monostearate; alkylene oxide adducts of alkyl phenols; esters of sorbitan/glycerol condensates with fatty acids and esters of sorbitan alkylene glycol condensates with fatty acids; diglycerol dialkoxide sodium lauryl sulfate, sodium dodecylbenzene sulfonate, cetyltrimethylammonium chloride, dodecylamine hydrochloride, laurylamide laurate ethylphosphate, triethylhexadecylammonium iodide, oleylaminodiethylamine hydrochloride, dodecylpyridinium salt, and isomers thereof. The dehazer can additionally have functional groups that react with the curable monomer or curable oligomer.

The amount of the dehazing agent added may be, for example, in the range of about 0.01 to 20 parts by mass (in several embodiments, about 0.1 to 15 parts by mass or about 0.2 to 10 parts by mass) relative to 100 parts by mass of the total of the nanoparticles, the curable monomer, and the curable oligomer.

The hard coat layer precursor that can be used to form the hard coat layer comprises the above nanoparticle mixture, a binder comprising a curable monomer and/or curable oligomer and a polyfunctional fluorinated (meth) acrylic compound, a reaction initiator, and, if necessary, a solvent such as Methyl Ethyl Ketone (MEK), 1-methoxy-2-propanol (MP-OH), and the like, and the above additives such as an ultraviolet absorber, a dehazing agent, a leveling agent, an ultraviolet reflecting agent, an antistatic agent, and the like. The hard coating precursor of some embodiments comprises a nanoparticle mixture and a binder, wherein the nanoparticles constitute 40 to 95 mass% of the total mass of the nanoparticles and the binder. 10 to 50 mass% of the nanoparticles have an average particle size in the range of 2 to 200nm, and 50 to 90 mass% of the nanoparticles have an average particle size in the range of 60 to 400 nm. A ratio of an average particle size of the nanoparticles having an average particle size in a range of 60nm to 400nm to an average particle size of the nanoparticles having an average particle size in a range of 2nm to 200nm is in a range of 2:1 to 200:1, and the binder includes a multifunctional fluorinated (meth) acrylic compound.

As is generally known in the art, the hard coating precursor may be prepared by mixing the specific components of the hard coating precursor. For example, the hardcoat precursor can be prepared by mixing curable monomers and/or curable oligomers in a solvent along with a reaction initiator and adding the solvent to prepare two or more differently sized modified or unmodified nanoparticle sols having a desired solids content. For example, a photoinitiator or a thermal polymerization initiator known in the art may be used as the reaction initiator. Depending on the curable monomer and/or curable oligomer used, the use of a solvent is not necessary.

When surface-modified nanoparticles are used, for example, a hard coating precursor may be prepared as follows. The inhibitor and the surface modifier are added to a solvent in a container (e.g., in a glass vial), and the resulting mixture is added to an aqueous solution in which the nanoparticles are dispersed, followed by stirring. The container is sealed and placed in an oven at elevated temperature (e.g., 80 ℃) for several hours (e.g., 16 hours). Next, water is removed from the solution at an elevated temperature (e.g., 60 ℃) using, for example, a rotary evaporator. The remaining water was removed from the solution by pouring the solvent into the solution and then evaporating the solution. It is sometimes preferred to repeat the latter half of the steps several times. By adjusting the volume of the solvent, the concentration of the nanoparticles can be adjusted to a desired concentration (mass%).

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, gravure coating, screen printing, and the like. The applied hard coat precursor is dried as needed and can be cured by polymerization methods known in the art such as optical polymerization using ultraviolet rays or electron beams, thermal polymerization, and the like. In this way, a hard coat layer can be formed on the substrate.

Examples of representative substrates to which the antifouling hardcoats of the present disclosure are applied include films, plastics (polymer sheets), glass sheets, and metal sheets. The film may be transparent or opaque. In the present disclosure, "transparent" means that the total light transmittance in the visible light range (380nm to 780nm) is at least 90%, and "opaque" means that the total light transmittance in the visible light range (380nm to 780nm) is less than 90%. Examples of representative thin films include films formed from: polyolefins (e.g., Polyethylene (PE), polypropylene (PP), etc.), polyurethanes, polyesters (e.g., polyethylene terephthalate (PET), etc.), poly (meth) acrylates (e.g., polymethyl methacrylate (PMMA), etc.), polyvinyl chloride, polycarbonates, polyamides, polyimides, phenol resins, cellulose diacetate, cellulose triacetate, polystyrene, styrene-acrylonitrile copolymers, acrylonitrile-butadiene-styrene copolymers (ABS), epoxy resins, polyacetates, or glass. The plastic (polymer sheet) may be transparent or opaque. Examples of representative plastics (polymer sheets) include plastics formed from: polycarbonate (PC), Polymethylmethacrylate (PMMA), styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymer (ABS), a blend of PC and PMMA, or a laminate of PC and PMMA. The foil may be flexible or rigid. In the present disclosure, "flexible foil" refers to a foil which does not undergo a substantially irreversible change and which can receive mechanical stress such as bending or elongation, and "rigid foil" refers to a foil which does not undergo a substantially irreversible change and which cannot receive mechanical stress such as bending or elongation. A representative flexible foil is one made of aluminum. Representative rigid metal sheets are sheets made of aluminum, nickel-chromium, and stainless steel.

The thickness of the thin film is in the range of about 5 μm to 500 μm (in several embodiments, about 10 μm to 200 μm or about 25 μm to 100 μm). The thickness of the plastic (polymer sheet) is in the range of about 0.5mm to 10cm (in several embodiments, about 0.5mm to 5mm or about 0.5mm to 3 mm). The thickness of the glass sheet or metal foil is in the range of about 5 μm to 500 μm or about 0.5mm to 10cm (in several embodiments, about 0.5mm to 5mm or about 0.5mm to 3 mm). These substrates can sometimes be effectively used even when the thickness deviates from the above range.

The hard coat may be applied to multiple surfaces of the substrate. In addition, multiple hard coatings may be applied to the surface of the substrate.

In several embodiments, to improve adhesion of the hard coat layer to the substrate, the surface of the substrate is primed or a primer layer is disposed on the surface of the substrate. In particular, priming or primer layers are particularly effective when the substrate comprises a poorly adhering material such as polypropylene, polyvinyl chloride, or the like, or when the substrate is a metal foil.

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

Examples of the material for the primer layer include (meth) acrylic resins ((homopolymers of (meth) acrylic esters, copolymers of two or more types of (meth) acrylic esters, or copolymers of (meth) acrylic esters and other polymerizable monomers), polyurethane resins (e.g., 2-solution curable polyurethane resins composed of a polyol and an isocyanate curing agent), (meth) acryl-polyurethane copolymers (e.g., acryl-polyurethane block copolymers), polyester resins, 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, chlorinated polypropylene, and copolymers and derivatives thereof, Chlorinated ethylene-vinyl acetate copolymer, acryl-modified chlorinated polypropylene, maleic anhydride-modified chlorinated polypropylene, and polyurethane-modified chlorinated polypropylene), and the like. When the substrate is a polypropylene film, it is advantageous that the primer comprises 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. The thickness of the primer layer is typically in the range of about 0.1 μm to 20 μm (in several embodiments, about 0.5 μm to 5 μm).

The substrate may also have a printed layer, a colored layer, a metal film layer, etc. with a desired pattern, if necessary.

Products comprising hardcoats of the disclosure can also have an adhesive layer, if necessary. For example, the adhesive layer may be disposed on the surface of the substrate on the opposite side when viewed from the hard coat layer. Rubber adhesives, acrylic adhesives, polyurethane adhesives, polyolefin adhesives, polyester adhesives, and silicon adhesives or pressure sensitive adhesives known in the art may be used as the adhesive layer. The adhesive layer may be formed by applying or extruding the adhesive and pressure sensitive adhesive directly onto the substrate, or the adhesive layer may be formed by applying the adhesive and pressure sensitive adhesive onto a release liner that 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 about 1 μm to 100 μm (in several embodiments, about 5 μm to 75 μm or about 10 μm to 50 μm). The adhesive or pressure sensitive adhesive may also contain the above-mentioned ultraviolet absorbers.

The hardcoat and/or adhesive layer may also have a release liner as is known in the art, if necessary. Materials known in the art and prepared by performing a silicon treatment or the like on paper or a polymer film may be used as the release liner.

The antifouling hardcoat of the present disclosure is useful, for example, in the following respects: optical displays (e.g., Cathode Ray Tube (CRT) and Light Emitting Diode (LED) displays), plastic cards, lenses or bodies of cameras, fans, door handles, faucet handles, mirrors, and household electronics such as vacuum cleaners, washing machines, and the like; personal Digital Assistants (PDAs), mobile phones, Liquid Crystal Display (LCD) panels, devices with touch sensor screens, removable computer screens, and the like, as well as the bodies of such devices, and the like. Furthermore, the antifouling hardcoats of the present disclosure are additionally useful, for example, in: furniture, doors and windows, toilets and baths, the interior/exterior of vehicles, lenses (of cameras or glasses), or solar power panels (solar panels).

The present disclosure provides various embodiments that include a hard coat layer or a hard coat layer precursor.

Example 1 is a hard coat comprising a nanoparticle mixture and a binder; the nanoparticles constitute 40 to 95 mass% of the entire mass of the hard coat layer; 10 to 50 mass% of the nanoparticles have an average particle size in the range of 2 to 200 nm; 50 to 90 mass% of the nanoparticles have an average particle size in the range of 60 to 400 nm; a ratio of an average particle size of nanoparticles having an average particle size in a range of 60nm to 400nm to an average particle size of nanoparticles having an average particle size in a range of 2nm to 200nm is in a range of 2:1 to 200: 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; wherein the multifunctional fluorinated (meth) acrylic compound comprises cyclic siloxane units.

Embodiment 2 is the hard coat of embodiment 1, wherein the nanoparticles are surface modified nanoparticles.

Embodiment 3 is the hard coat of embodiment 1 or embodiment 2, wherein the multifunctional 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, wherein the multifunctional fluorinated (meth) acrylic compound has 3 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 comprises 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 comprises an ultraviolet absorber.

Example 8 is a hardcoat precursor comprising a nanoparticle mixture and a binder; the nanoparticles constitute 40 to 95 mass% of the total mass of the nanoparticles and the binder; 10 to 50 mass% of the nanoparticles have an average particle size in the range of 2 to 200 nm; 50 to 90 mass% of the nanoparticles have an average particle size in the range of 60 to 400 nm; a ratio of an average particle size of nanoparticles having an average particle size in a range of 60nm to 400nm to an average particle size of nanoparticles having an average particle size in a range of 2nm to 200nm is in a range of 2:1 to 200: 1; wherein the particle size distribution of the nanoparticles is bimodal or multimodal; and the binder comprises a multifunctional fluorinated (meth) acrylic compound; wherein the multifunctional fluorinated (meth) acrylic compound comprises cyclic siloxane units.

Examples of the invention

Specific embodiments of the present disclosure are set forth in the following examples, but the present invention is not limited to these embodiments. All "parts" and "percentages" are by mass unless otherwise specified.

Evaluation method

The properties of the hard coat of the present disclosure were evaluated according to the following methods. The hard coat layer is formed by applying a hard coat layer precursor onto a substrate and irradiating the precursor with ultraviolet rays. The hard coat layer was evaluated while it was supported on the substrate.

1. Hardness of pencil

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

2. Optical characteristics

The haze of the hard coat layer was measured using an NDH-5000W haze meter (obtained from Nippon Denshoku Industries Co., Ltd.)) according to JIS K7136 (2000).

3. Contact angle

The water contact angle of the hardcoat surface was measured by sessile drop method using a contact angle meter (obtained by Kyowa Kaimen Kagaku co., Ltd.) under the product name "DROPMASTER FACE"). For the measurement of the static contact angle, the volume of the liquid droplet was set to 4 μ L. The value of the water contact angle was calculated from the average of five measurements.

4. Ink repellency test

After drawing a straight line on the hard coat using a permanent mark (Maki (black), obtained from Zebra co., Ltd.) the external appearance was visually observed. The sample that repels ink and does not form lines was rated as good, while the sample that does not repel ink and forms lines was rated as bad.

5. Abrasion resistance test

Scratch resistance of the hard coating was evaluated by measuring optical characteristics and water contact angle after abrasion resistance testing. In the fabric abrasion resistance test, 32mm width JIS test fabrics (obtained from Japanese Industrial Standards Committee) were used under a load of 500g, and 32mm square pieces of #0000 steel wool were used under a load of 1kg in the steel wool abrasion resistance test. The hard-coated surface was subjected to 200 abrasion cycles of 85mm stroke at a rate of 60 cycles/min. Fig. 2 shows a schematic diagram of a wear resistance testing apparatus 60(MC-157C friction tester, available from Imoto Machinery co., Ltd.). Here, the sample 10 is fixed to the top of the tray 61, and the load of the weight 63 is applied to the fabric or steel wool 64 by the stylus 62 so as to brush the surface of the sample by moving the tray 61 back and forth. The abrasion resistance test simulates the scratches that occur when rubbed and washed.

Table 1: reagents and raw materials

Preparation of surface-modified silica Sol (Sol 1)

A surface-modified silica sol ("sol 1") was prepared as follows. First, 5.95g of SILQUEST A174 and 0.5g of PROSTAB were added to a mixture of 400g of NALCO 2329 and 450g 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 ℃ for 16 hours. Water was removed from the resulting solution with a rotary evaporator until the solid content of the solution reached almost 45 mass% at 60 ℃. Two hundred grams of 1-methoxy-2-propanol were added to the resulting solution and the remaining water was removed using a rotary evaporator at 60 ℃. The second half of the procedure was repeated twice to further remove the water from the solution. Finally, all SiO was done by adding 1-methoxy-2-propanol₂The concentration of the nanoparticles was adjusted to 45 mass%, and surface-modified SiO having an average particle size of 75nm was obtained₂SiO of nanoparticles₂A sol (hereinafter referred to as "sol 1").

Preparation of surface-modified silica Sol (Sol 2)

A surface-modified silica sol ("sol 2") was prepared as follows. Modification was carried out in the same manner as for sol 1, except that 400g of NALCO 2327, 25.25g of SILQUEST A174 and 0.5g of PROSTAB were used, and a surface-modified SiO containing 45 mass% was obtained₂SiO of nanoparticles₂Sol (hereinafter referred to as "sol 2") in which the nanoparticles have an average particle size of 20 nm.

Preparation of hard coating precursor (HC-1)

First, 11.34g of sol 1, 5.88g of sol 2, 2.25g of EBECRYL4858 and 0.25g of SR340 were mixed. Next, 0.20 g of IRGACURE 2959 was added to the mixture as an optical polymerization initiator, and 0.001g of BYK-UV3500 was added to the mixture as a leveling agent. Then, by adding 1-methoxy-2-propanol, the mixture was adjusted so that the solid content was 50 mass%, and thus a hard coat precursor HC-1 was prepared.

Production of hard coating precursor (HC-2)Prepare for

First, 11.34g of sol 1, 5.88g of sol 2, 2.25g of EBECRYL4858 and 0.25g of SR340 were mixed. Next, 0.17g of HFPO urethane acrylate was added to the mixture as an antifouling agent, 0.1g of the ultraviolet photoinitiator IRGACURE 2959 was added to the mixture as an optical polymerization initiator, and 0.001g of BYK-UV3500 was added to the mixture as a leveling agent. Then, by adding 1-methoxy-2-propanol, the mixture was adjusted so that the solid content was 50 mass%, and thus hard coat precursor HC-2 was prepared. HFPO urethane acrylates are monofunctional fluorinated (meth) acrylic compounds.

Preparation of hardcoat precursors (HC-3 to HC-8)

Hardcoat precursors HC-3 to HC-8 were prepared in the same manner as HC-2 using the formulations described in Table 2. KAYARAD UX-5000 is used as the acrylate oligomer in HC-6 to HC-8, and KY-1203 is used as the polyfunctional (meth) acrylic compound (antifouling agent) in HC-4, HC-5 and HC-8. The compositions of HC-1 to HC-8 are shown in Table 2.

Example 1

A PMMA substrate (Acrylite L-001, 100 × 53 × 2mm, available from Mitsubishi viscose Co., Ltd.) was fixed on top of a stainless steel plate equipped with a level.A hard coating precursor HC-4 was applied to the PMMA substrate using a #16Meyer rod and dried at 60 ℃ for 5 minutes.Next, the coating surface was irradiated with ultraviolet rays 10 times at a line rate of 13 m/minute using an H-valve (model DRS) manufactured by deep UV systems Inc. (Fusion UV systems Inc.) in a nitrogen-containing atmosphere (emissivity: about 1400mJ @²). The thickness of the hard coat layer was about 10 μm. Thus, the hard coat layer of example 1 was formed on the PMMA substrate.

Example 2 and example 3 and comparative examples 1 to 5

A hard coat layer was formed on a PMMA substrate using hard coat layer precursors HC-1 to HC-3 and HC-5 to HC-8 in the same manner as in example 1. The results of evaluating these hard coatings are shown in tables 3 and 4.

As shown in Table 3, the hard coat layer containing a fluorinated (meth) acrylic compound as an antifouling agent (examples 1 and 2: KY-1203, comparative examples 2 and 3: HFPO urethane acrylate) exhibited a pencil hardness of 8H, which is equivalent to that of the hard coat layer (comparative example 1) containing no fluorinated (meth) acrylic compound. Addition of an appropriate amount of the fluorinated (meth) acrylic compound does not affect the pencil hardness of the hard coat layer. When the fluorinated (meth) acrylic compound is added, the water contact angle increases. HC-4 (example 1) and HC-5 (example 2) showed favorable ink repellency even after fabric abrasion resistance testing. On the other hand, the fabric abrasion resistance test of HC-3 (comparative example 3) was inferior in ink repellency in which the amount of HFPO urethane acrylate used as an antifouling agent was increased.

In addition to the fabric abrasion resistance test, the results of the steel wool abrasion resistance test are also shown in table 4. The water contact angle and ink repellency before and after the fabric abrasion resistance test are compared, and the water contact angle, ink repellency, and optical properties before and after the steel wool abrasion resistance test are compared. Both HC-7 (comparative example 5) and HC-8 (example 3) show water contact angles in excess of 100 degrees and favorable ink repellency at the beginning and after the fabric abrasion resistance test. The hardcoat of example 2, which is a urethane acrylate oligomer, comprising UX-5000, a multifunctional acrylate having multiple acrylate groups, had higher scratch resistance than the hardcoat of example 3, which comprises EBECRYL 4858.

As a result of the addition of the fluorinated (meth) acrylic compound, the steel wool abrasion resistance is improved. HC-7 (comparative example 5) and HC-8 (example 3) have a change in haze value (Δ haze) after steel wool abrasion resistance testing of less than 0.1%. Due to the fluorinated (meth) acrylic compound, the friction coefficient of the surface of the hard coat layer is reduced and the steel wool abrasion resistance of the hard coat layer is improved. Specifically, HC-8 (example 8 including KY-1203) had excellent scratch resistance and exhibited high durability with respect to antifouling property. The ink repellency of HC-8 is unchanged even after the steel wool abrasion resistance test. The hard coat layer containing a polyfunctional fluorinated (meth) acrylic compound having a siloxane unit exhibits higher antifouling durability than those containing a monofunctional fluorinated (meth) acrylic compound.

Parts list：

60 wearability testing arrangement

61 column plate

62 stylus

63 weight

64 fabrics or steel wool

Claims (8)

1. A hard coat comprising a mixture of nanoparticles and a binder;

the nanoparticles constitute 60 to 90 mass% of the entire mass of the hard coat layer;

10 to 50 mass% of the nanoparticles have an average particle size in the range of 2 to 200 nm;

50 to 90 mass% of the nanoparticles have an average particle size in the range of 60 to 400 nm;

a ratio of the average particle size of nanoparticles having an average particle size in the range of 60nm to 400nm to the average particle size of nanoparticles having an average particle size in the range of 2nm to 200nm is in the range of 2:1 to 200: 1;

the particle size distribution of the nanoparticles is bimodal or multimodal;

the binder constitutes 10 to 40 mass% of the entire mass of the hard coat layer, and contains a polyfunctional fluorinated (meth) acrylic compound, a reaction product thereof, or a combination thereof; wherein the multifunctional fluorinated (meth) acrylic compound comprises cyclic siloxane units.

2. The hard-coat according to claim 1, wherein the nanoparticles are surface-modified nanoparticles.

3. The hard coat according to claim 1, wherein the polyfunctional fluorinated (meth) acrylic compound is a perfluoroether compound having two or more (meth) acrylic groups.

4. The hardcoat of claim 1 wherein the multifunctional fluorinated (meth) acrylic compound has 3 or more (meth) acrylic groups.

5. The hardcoat of claim 1 wherein the nanoparticles are inorganic oxide nanoparticles and the multifunctional fluorinated (meth) acrylic compound comprises siloxane units.

6. The hard-coat according to claim 5, wherein the nanoparticles are silica nanoparticles.

7. The hardcoat of claim 1 wherein the binder further comprises an ultraviolet absorber.

8. A hardcoat precursor comprising a mixture of nanoparticles and a binder;

the nanoparticles constitute 60 to 90 mass% of the total mass of the nanoparticles and the binder;

10 to 50 mass% of the nanoparticles have an average particle size in the range of 2 to 200 nm;

50 to 90 mass% of the nanoparticles have an average particle size in the range of 60 to 400 nm;

a ratio of the average particle size of nanoparticles having an average particle size in the range of 60nm to 400nm to the average particle size of nanoparticles having an average particle size in the range of 2nm to 200nm is in the range of 2:1 to 200: 1; wherein the particle size distribution of the nanoparticles is bimodal or multimodal; and is

The binder constitutes 10 to 40 mass% of the entire mass of the hard coat layer, and contains a polyfunctional fluorinated (meth) acrylic compound; wherein the multifunctional fluorinated (meth) acrylic compound comprises cyclic siloxane units.