JP6206712B2 - Hard coat film for molding and method for producing the same - Google Patents

Description

The present invention relates to a molding hard coat film used for the production of a resin molded product by an in-mold molding method, a film insert molding method, or a vacuum molding method, and a method for producing the same.

  Resin-molded products are often used for portable information terminal devices such as mobile phones, notebook computers, home appliances, and automobile interior and exterior parts. As products become more commoditized, the need for differentiation in these products is increasing. Conventionally, as a method for decorating a resin molded product, a colored paint is applied or screen printed on the surface of a three-dimensional resin molded product by injection molding or the like. Furthermore, a method of applying a clear hard coat by spraying or dipping has been performed for the purpose of protecting the surface of the product.

However, such conventional methods are difficult to decorate with high design, and there is a concern about the impact on the work environment by chemical substances such as volatile solvents contained in the paint used in spray coating etc. There is. Therefore, as an alternative method, an in-mold molding method, a film insert molding method, or a vacuum molding method using a decorative film with high design in which a hard coat layer is provided on a printed base film has been proposed.

The in-mold molding method is a technique in which a decorative film is adhered to the surface of a resin molding by simultaneously performing vacuum molding and injection in an injection mold. Moreover, the said film insert molding method heats a decoration film (preliminary heating), and after obtaining the molding of a decoration film with a metal mold | die, the decoration film molding and resin which were preformed by injection molding as a next process In this method, the molded product is bonded and integrated. The vacuum molding method is a method in which the decorative film is heated (preliminary heating) and softened under vacuum, and then the decorative film is evacuated and bonded to the surface of the resin molding while being stretched ( (See Patent Document 1, Patent Document 2, etc.).

JP 2009-274378 A JP 2012-81628 A

When a decorative film is produced by printing directly on a base film, the adhesion between the decorative layer (printing layer) and the base film tends to be insufficient, causing a problem of dropping off the decorative layer. For this reason, providing the primer layer which has adhesiveness with both a base film and a decoration layer between a base film and a decoration layer is common as a structure of a decoration film. When this decorative film is used as a film for molding, the physical properties (elongation) of following the elongation of the base film during molding, in addition to the adhesion between the base film and the decorative layer as the properties of the primer layer. Needed.

However, in the primer layer made of, for example, a two-component urethane resin that is generally used in conventional decorative films, the adhesion of the base film and the decorative layer is good, but the base film is not suitable for molding. Since the physical property (elongation) following the elongation is insufficient, there is a problem that the decorative layer is broken at the time of molding. On the other hand, when a primer layer made of, for example, a polyester resin having physical properties (elongation) that follows the elongation of the base film at the time of molding is provided, the adhesion with the base film or the decorative layer is reduced, and the decoration is performed. There is a problem that the primer layer is eroded by the solvent component contained in the printing ink for forming the layer.

Therefore, the present invention has a primer layer that is excellent in adhesion between both the base film and the decorative layer, and has a moldability (elongation), a hard property, and a winding hard coat film that is excellent in winding properties. And it aims at providing the manufacturing method.

As a result of intensive studies to solve the above problems, the present inventor has found that the above problems can be solved by an invention having the following configuration.
That is, the present invention is as follows.

The first invention is a molding hard coat film in which a decorative layer is formed on one surface of a base film via a primer layer, and a hard coat layer is formed on the other surface. It contains a vinyl chloride-vinyl acetate copolymer resin and a polymethyl methacrylate resin, and the blending ratio (parts by weight) of the vinyl chloride-vinyl acetate copolymer resin and the polymethyl methacrylate resin is in the range of 80/20 to 25/75. It is a hard coat film for molding characterized by being.

2nd invention is a hard-coat film for shaping | molding characterized by the glass transition temperature (Tg) of the said vinyl chloride-vinyl acetate copolymer resin being 65 degreeC or more in the said 1st invention.
A third invention is the molding hard coat film according to the first or second invention, wherein the primer layer contains inorganic or organic fine particles.

A fourth invention is the hard coat film for molding according to any one of the first to third inventions, wherein the primer layer has a thickness in the range of 0.1 μm to 1.0 μm.
A fifth invention is a molding hard coat film according to any one of the first to fourth inventions, wherein the hard coat layer contains an ionizing radiation curable resin.

  A sixth invention is a molding hardt film according to any one of the first to fifth inventions, wherein the base film is a polyethylene terephthalate film, a polycarbonate film, or a polymethyl methacrylate film. .

  7th invention is a primer which contains a vinyl chloride-vinyl acetate copolymer resin and polymethylmethacrylate resin in the range of 80 / 20-25 / 75 in the compounding ratio (weight part) on one surface of a base film. After coating and drying the layer coating, the other surface is coated with a coating for the hard coat layer containing an ionizing radiation curable resin and dried, and after photocuring treatment with ionizing radiation, It is a manufacturing method of the hard coat film for shaping | molding characterized by forming a decoration layer on a primer layer.

  According to the present invention, a vinyl chloride-vinyl acetate copolymer resin and a polymethyl methacrylate resin are mixed at a blending ratio (parts by weight) of the vinyl chloride-vinyl acetate copolymer resin and the polymethyl methacrylate resin of 80 / 20-25 / It has a primer layer that is contained in the range of 75 and has excellent adhesion between the base film and the decorative layer, and also has excellent moldability (elongation), hardware, and winding properties. A hard coat film can be provided.

It is sectional drawing which shows the layer structure of the hard-coat film for shaping | molding concerning this invention.

Hereinafter, although the form for implementing this invention is demonstrated in detail, this invention is not necessarily limited to the following embodiment.
As shown in FIG. 1, a molding hard coat film 5 according to an embodiment of the present invention has a decorative layer 3 formed on one surface of a base film 1 with a primer layer 2 interposed therebetween. This is a molding hard coat film in which a hard coat layer 4 is formed on the other surface of the film 1.

[Base film]
First, the base film 1 will be described.
In the present invention, the base film 1 of the molding hard coat film 5 is preferably a film that can be thermoformed and has a low elongation stress and can be stretched with a weak force. Specifically as a base film 1, a polyethylene terephthalate film, a polymethylmethacrylate film, and a polycarbonate film can be illustrated preferably.

In the case of the polyethylene terephthalate film, a general-purpose biaxially stretched polyethylene terephthalate film may be used, but in order to obtain better moldability, it is particularly preferable to use a biaxially stretchable polyethylene terephthalate film. This biaxially stretchable polyethylene terephthalate film has a low heat softening temperature, can be stretched with a weak force, and is a relatively inexpensive material.
Moreover, both the said polycarbonate film and the said polymethylmethacrylate film are unstretched films, and can be utilized suitably for any shaping | molding method.

In the present invention, the thickness of the base film 1 is not particularly limited, but the primer layer, the decorative layer, the processing conditions of the hard coat layer, and the economics, mechanical strength, handling properties, etc. of the base film. Therefore, it is preferably in the range of 25 μm to 250 μm, more preferably in the range of 50 μm to 125 μm.

When the surface of the base film 1 is subjected to surface treatment such as corona treatment or low-temperature plasma treatment, or when the base film 1 is formed, a benzotriazole type or benzophenone type for the purpose of imparting light resistance to the resin material Addition of ultraviolet absorbers, addition of lubricants for the purpose of improving film runnability, and easy adhesion treatment using a thermoplastic resin or a thermosetting resin during or after the formation of the base film 1 You can also. In addition, for the purpose of imparting antistatic properties, antistatic treatment and the like can also be performed.

[Primer layer]
Next, the primer layer 2 will be described.
In the present invention, the primer layer 2 contains vinyl chloride-vinyl acetate copolymer resin and polymethyl methacrylate resin as main components, and the blending ratio (parts by weight) thereof is vinyl chloride-vinyl acetate copolymer resin / polymethyl. It is important that the methacrylate resin is in the range of 80/20 to 25/75.

If the blending ratio of the vinyl chloride-vinyl acetate copolymer resin to the polymethyl methacrylate resin is more than 80 parts by weight, the solvent resistance of the dried coating film of the primer layer 2 decreases, so that the paint (ink Etc.) primer layer (for example, typical composition of ink solvent: NPR (n-propyl alcohol) / toluene / ethyl acetate / MEK (methyl ethyl ketone) = 30/30/20/20 (parts by weight)) The coating film is eroded, and the decorativeness and adhesion are liable to decrease, and problems such as pressure bonding or blocking occur when the molding film is wound up. On the other hand, when the blending ratio of the vinyl chloride-vinyl acetate copolymer resin to the polymethyl methacrylate resin is less than 25 parts by weight, the adhesion between the base film and the decorative layer is lowered.

The ratio of vinyl chloride and vinyl acetate in the vinyl chloride-vinyl acetate copolymer resin is not particularly limited, but is preferably vinyl chloride / vinyl acetate = 65/35 to 90/10 (parts by weight). More preferably, it is 70/30 to 90/10 (parts by weight). When the ratio of vinyl chloride is low, there is a concern that problems such as a decrease in solvent resistance, an operational problem due to a decrease in heat resistance, a pressure bonding during winding, and a blocking problem may occur. For example, when the ratio of vinyl chloride is less than 65 parts by weight, there is a problem that the hardness and solvent resistance of the coating film are likely to be lowered. On the other hand, if the ratio is more than 90 parts by weight, the solubility in a solvent is lowered as the flexibility is lowered and the solvent resistance is improved.

The ratio between vinyl chloride and vinyl acetate can be calculated from the following formula I.
[Formula I]
Glass transition temperature of vinyl chloride-vinyl acetate copolymer resin (Tg) = glass transition temperature of polyvinyl chloride (87 ° C.) × ratio of vinyl chloride (a) + glass transition temperature of polyvinyl acetate (29 ° C.) × vinyl acetate Ratio (b = 1-a)

In the present invention, the glass transition temperature (Tg) of the vinyl chloride-vinyl acetate copolymer resin is preferably 65 ° C. or higher. When the glass transition temperature is less than 65 ° C., there are concerns that operational problems due to a decrease in heat resistance, and problems such as pressure bonding and blocking when the film is wound up may occur. The polymethyl methacrylate resin is a homopolymer and usually has a glass transition temperature of 105 ° C.

The primer layer 2 has an ultraviolet absorber such as benzotriazole or benzophenone for the purpose of imparting light resistance, various leveling agents (fluorine, siloxane, acrylic, etc.) for the purpose of improving coating properties, Light stabilizers, antistatic treatment agents, antifoaming agents, antistatic agents, flame retardants and the like can also be blended. In addition, when used as a solvent for primer layer paints, aromatic solvents such as toluene and xylene, aliphatic solvents such as cyclohexane, methylcyclohexane and ethylcyclohexane, ester solvents such as ethyl acetate and butyl acetate, A ketone solvent such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and anone, an alcohol solvent such as methanol, ethanol, isopropyl alcohol, n-propyl alcohol, and butanol, or a mixture of the above solvents can be used. Usually, a general-purpose solvent used for adjusting the solvent-based paint can be used.

The primer layer 2 is formed by a known coating method such as gravure coating, micro gravure coating, fountain bar coating, slide die coating, slot die coating, screen printing method, or the like. After installation, it is usually dried at a temperature of about 50 to 100 ° C.

The coating thickness after drying of the primer layer 2 is not particularly limited, but is usually preferably in the range of 0.1 μm to 1.0 μm, more preferably in the range of 0.2 μm to 0.5 μm. . When the coating thickness is less than 0.1 μm, when the decoration layer is formed on the primer layer, the adhesion layer is eroded by the solvent in the decoration layer paint and the adhesion layer is eroded. There is a problem that it tends to cause a decrease. On the other hand, if the coating thickness exceeds 1.0 μm, the effect of improving the adhesion with the base film and the decorative layer cannot be obtained, and on the contrary, the cost becomes high, and when the film for molding is stretched, Whitening tends to occur, which is not preferable.

It is preferable to add inorganic or organic fine particles to the primer layer 2 from the viewpoint of preventing pressure bonding and blocking when the molding film is wound. In this case, the blending amount (part by weight) is the thermoplastic resin forming the primer layer 2 (including the resin when the resin of the present invention is included) / inorganic or organic fine particles = 99.8 / 0.2 to 95. It is preferably 0.0 / 5.0. When the blending amount of the fine particles exceeds 5.0 parts by weight, it is not preferable because the transparency is lowered and whitening is likely to occur when the molding hard coat film is stretched. On the other hand, there is a concern that a sufficient effect is not exhibited when the amount of the fine particles is less than 0.2 parts by weight.

Examples of the inorganic fine particles include fine particles such as alumina, zinc oxide, and silica, and examples of the organic fine particles include fine particles such as polymethyl methacrylate and melamine / formaldehyde condensate. As the particle size, for example, it is preferable to use fine particles of 0.05 μm to 0.50 μm. When the particle diameter is less than 0.05 μm, blocking does not occur when the primer layer surface and the hard coat layer surface are rolled up, but it is not preferable because it is easy to press-bond. On the other hand, if the particle diameter is more than 0.50 μm, it is not preferable because the effect of preventing further pressure bonding or blocking cannot be obtained, and on the contrary, the cost is increased and the external haze is increased and the transparency is easily lowered.

[Decorative layer]
Next, the decoration layer 3 will be described.
The decorative layer 3 formed on the primer layer is composed of, for example, a picture layer and / or a concealing layer, a metal vapor deposition layer, and the like. Here, the pattern layer is a layer provided to express a pattern such as a pattern or characters, and the concealing layer is a solid layer, and is a layer provided to conceal the coloring of the resin or the like. . Moreover, a metal vapor deposition layer is the layer which vapor-deposited one part or the whole surface, and is provided for the purpose of expressing the layer provided for concealing coloring etc. of resin etc., or a resin layer in a metal tone. Is a layer.

The decorative layer 3 (for example, a pattern layer and / or a concealing layer) can be formed on the primer layer 2 by a known printing method such as gravure printing, offset printing, or screen printing with a printing ink. Although there is no restriction | limiting in particular in the formation thickness of the decoration layer 3, For example, 3-50 micrometers is preferable from a design viewpoint, More preferably, it is 10-30 micrometers. Moreover, the said metal vapor deposition layer can be formed into a film by methods, such as sputtering.

Examples of printing ink binders used to form the decorative layer 3 include polyester resins, vinyl chloride-vinyl acetate copolymer resins, polyurethane resins, acrylic two-component curable resins, cellulose resins, and acrylic resins. It can be illustrated. The printing ink is usually provided in a form dissolved or dispersed in a solvent. Solvents include aromatic solvents such as toluene and xylene, aliphatic solvents such as cyclohexane, methylcyclohexane and ethylcyclohexane, ester solvents such as ethyl acetate and butyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone and anone. A ketone solvent, an alcohol solvent such as methanol, ethanol, isopropyl alcohol, n-propyl alcohol, butanol, or a mixture of the above solvents can be used. Usually, a general-purpose solvent used for adjusting the solvent-based paint can be used.

[Hard coat layer]
Next, the hard coat layer 4 will be described.
In the present invention, the resin contained in the hard coat layer 4 can be used without any particular limitation as long as it is a resin that forms a film. In particular, the surface of the hard coat layer is imparted with hardness (pencil hardness, scratch resistance). In addition, the degree of cross-linking can be adjusted by the exposure amount of ultraviolet rays, and the ionizing radiation curable resin can be adjusted in terms of the extensibility and surface hardness (pencil hardness, scratch resistance) of the hard coat layer. Is preferably used.

  The ionizing radiation curable resin used in the present invention is a transparent resin that is cured by irradiation with ultraviolet rays (hereinafter abbreviated as “UV”) or electron beams (hereinafter abbreviated as “EB”). For example, it is not specifically limited, For example, it can select suitably from urethane acrylate-type resin, polyester acrylate-type resin, etc. Preferred examples of the ionizing radiation curable resin include those composed of a polyfunctional acrylate curable with UV or EB having two or more (meth) acryloyl groups in the molecule. Specific examples of UV or EB curable polyfunctional acrylates having two or more (meth) acryloyl groups in the molecule include neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, Polyol polyacrylates such as trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, bisphenol A Diglycidyl ether diacrylate, neopentyl glycol diglycidyl ether diacrylate, 1,6-hexanediol diglycidyl ether di (meth) acrylate, etc. Polyester (meth) acrylate, polyhydric alcohol, polyhydric isocyanate, and hydroxyl group-containing compounds that can be obtained by esterifying xyl (meth) acrylate, polyhydric alcohol and polyhydric carboxylic acid and / or anhydride and acrylic acid The urethane (meth) acrylate obtained by making (meth) acrylate react, polysiloxane poly (meth) acrylate, etc. can be mentioned. In addition, you may mix and use 3 or more types of polyfunctional acrylate.

In the present invention, a coating containing one or a mixture of the above ionizing radiation curable resins is applied to a base film (for example, polyethylene terephthalate film) with a dry coating thickness of 3 μm, and then cured by UV or EB irradiation. When a test piece having a width of 15 mm and a length of 150 mm was prepared and the test piece was pulled at a tensile speed of 50 mm / min in an environment of a temperature of 25 ° C. and a humidity of 50% RH, a crack occurred in the hard coat layer. The hard coat layer (ionizing radiation curable resin) having an elongation rate of 1 to 150% (based on the test method specified in JIS K5600-5-4) and a pencil hardness specified in JIS K5600 of B to 2H ) Is preferable.

Moreover, as resin contained in the said hard-coat layer 4, other than the above-mentioned ionizing radiation curable resin, thermoplastic resins, such as polyethylene, a polypropylene, a polystyrene, a polycarbonate, polyester, an acryl, styrene-acryl, a fiber, Thermosetting resins such as phenolic resins, urea resins, unsaturated polyesters, epoxies, and silicon resins may be included within the range that does not impair the effects of the present invention, that is, the extensibility and hardness of the hard coat layer, and scratch resistance. .

As the photopolymerization initiator for the ionizing radiation curable resin contained in the hard coat layer 4, known ones such as acetophenones and benzophenones can be used.

In the present invention, it is preferable that the hard coat layer 4 contains inorganic oxide fine particles from the viewpoint of improving the surface hardness (scratch resistance). In this case, the average particle diameter of the inorganic oxide fine particles is preferably in the range of 5 to 50 nm, more preferably in the range of 10 to 20 nm. If the average particle diameter is less than 5 nm, it is difficult to obtain sufficient surface hardness. On the other hand, when the average particle diameter exceeds 50 nm, the gloss and transparency of the hard coat layer are lowered, and the flexibility is also lowered.

In the present invention, examples of the inorganic oxide fine particles include alumina and silica. Among these, alumina containing aluminum as a main component is particularly suitable because it has a high hardness and can obtain an effect with a smaller amount of addition than silica.

In the present invention, the content of the inorganic oxide fine particles is preferably 0.1 to 5.0 parts by weight with respect to 100 parts by weight of the solid content of the hard coat layer coating composition. When the content of the inorganic oxide fine particles is less than 0.1 parts by weight, it is difficult to obtain an effect of improving the surface hardness (abrasion resistance). On the other hand, if the content exceeds 5.0 parts by weight, the haze increases, and the design of the resin molded body using the molding hard coat film may be impaired.

Further, as other additives to be added to the hard coat layer 4, as long as the effects of the present invention are not impaired, an antifoaming agent, a leveling agent, a surface tension adjusting agent, an antifouling agent, an antioxidant, an antistatic agent, You may contain a ultraviolet absorber, a light stabilizer, etc. as needed.
In addition to the ionizing radiation curable resin described above, the hard coat layer 4 is formed on the base film 1 with a paint in which inorganic oxide fine particles, a polymerization initiator, other additives and the like are dissolved and dispersed in an appropriate solvent. It is formed by coating and drying. The solvent can be appropriately selected depending on the solubility of the resin contained therein, and may be any solvent that can uniformly dissolve or disperse at least solids (resin, polymerization initiator, and other additives). Examples of such solvents include aromatic solvents such as toluene and xylene, aliphatic solvents such as cyclohexane, methylcyclohexane and ethylcyclohexane, ester solvents such as ethyl acetate and butyl acetate, acetone, methyl ethyl ketone and methyl isobutyl. A ketone solvent such as ketone, an alcohol solvent, or a mixture of the above solvents can be used.

The coating thickness of the hard coat layer 4 is not particularly limited, but is preferably in the range of 1 to 10 μm, for example. If the coating thickness is less than 1 μm, it will be difficult to obtain the required hardness. Moreover, when the coating film thickness is thicker than 10 μm, it becomes difficult to obtain good extensibility.
The coating method of the hard coat layer 4 is not particularly limited, but the coating thickness can be adjusted such as gravure coating, micro gravure coating, fountain bar coating, slide die coating, slot die coating, etc. Coating is possible with an easy method. In addition, the coating-film thickness of the hard-coat layer 4 can be measured by actually measuring with a micrometer.

  As described above, in the present invention, a vinyl chloride-vinyl acetate copolymer resin and a polymethyl methacrylate resin are mixed at a blending ratio (parts by weight) of the vinyl chloride-vinyl acetate copolymer resin and the polymethyl methacrylate resin of 80 / part. By providing a primer layer contained in the range of 20-25 / 75, the primer layer is excellent in adhesion between both the base film and the decorative layer, and the base film and the decoration through the primer layer. Adhesion with the layer can be improved. And according to this invention, the hard coat film for shaping | molding excellent also in the moldability (elongation), hard property, and winding-up property is obtained.

The following examples illustrate the invention, but are not intended to limit the invention.
Unless otherwise specified, “parts” and “%” described below represent “parts by weight” and “% by weight”, respectively.

[Example 1]
<Preparation of hard coat layer paint>
40 parts of acrylic polymer UV curable resin “8KX-012C (trade name)” (solid content 39%, manufactured by Taisei Fine Chemical Co., Ltd.) and urethane acrylate UV curable resin “8BR-500 (trade name)” (solid content) 37 parts, 50% by Taisei Fine Chemical Co., Ltd., and 10 parts urethane acrylate UV curable resin “UN904 (trade name)” (100% solids, Negami Kogyo Co., Ltd.), Irgacure 184 (photopolymerization initiator) 5 parts, hindered amine compound “TINUVIN 770DF (trade name)” (BASF) 0.5 part, hydroxyphenyl triazine compound “TINUVIN 479 (trade name)” (BASF) 0. 5 parts, leveling agent RS75 (fluorine leveling agent, manufactured by DIC) 0.3 part and aluminum Fine particles "ALMIBKH06 (trade name)" with an average particle size of 13% (average particle size 13 nm, manufactured by CIK Nanotech Co., Ltd.) 3% solids in butyl acetate / n-propyl alcohol = 50/50 (wt%) A hard coat layer coating material was prepared by diluting until the solid content concentration in the coating material became 20% and stirring sufficiently.
The acrylic polymer UV curable resin 8KX-012C has a weight average molecular weight Mw of 2,5000, an elongation of 40%, and a pencil hardness of H. The urethane acrylate ultraviolet curable resin 8BR-500 has a weight average molecular weight Mw of 180,000 and an elongation ratio of pencil hardness HB without cracking until the base substrate (polyethylene terephthalate film) is broken. The urethane acrylate ultraviolet curable resin UN904 has a weight average molecular weight Mw of 4,900, an elongation of 4.0%, and a pencil hardness of 2H.

<Preparation of primer layer paint>
Vinyl chloride-vinyl acetate copolymer resin “Solvine C (trade name)” (glass transition point 70 ° C., manufactured by Nissin Chemical Industry Co., Ltd.) with a mixed solvent consisting of ethyl acetate / methyl isobutyl ketone = 40/60 (parts by weight) Dissolved to prepare a solution having a solid content of 15%. Next, 50 parts of dissolved vinyl chloride-vinyl acetate copolymer resin “Solvine C” and polymethyl methacrylate resin “Acryt 0404EA-P (trade name)” (solid content 40%, glass transition point 105 ° C., Taisei Fine Chemical Co., Ltd.) 50 parts main product, leveling agent “BYK-354 (trade name)” (acrylic leveling agent, manufactured by Big Chemie Japan) 0.2 part, UV absorber “TINUVIN 928 (trade name)” (benzotriazole type) A primer layer coating material was prepared by adjusting 1.0 part of a UV absorber (manufactured by BASF) with toluene / methyl isobutyl ketone = 30/70 (wt%) so that the solid content in the coating material would be 5%.

<Decorative layer paint>
A two-component reaction curable screen ink “SS16-000 (trade name)” (urethane type, manufactured by Toyo Ink Manufacturing Co., Ltd.) was used.

<Production of hard coat film for molding>
1. For solvent resistance and heat resistance tests, the primer layer paint is applied to one side of a 75-μm-thick polymethyl methacrylate film (manufactured by Sumitomo Corporation) with a bar coater, and dried with hot air at 90 ° C. for 1 minute. A primer layer having a thickness of 0.3 μm was formed.
2. Two samples were prepared for the adhesion test. The primer layer paint is applied to one side of the polymethyl methacrylate film with a bar coater, dried with hot air at 90 ° C. for 1 minute to form a primer layer having a coating thickness of 0.3 μm, and the primer layer and the substrate film Sample No. 1 for the adhesion test was prepared. Furthermore, on the primer layer of sample No.1, using a 200 μm screen mesh, solid printing with the above decorative layer paint (screen printing ink), drying with hot air at 60 ° C. for 30 minutes, and decorating with a coating thickness of 20 μm A layer (solid print layer) was formed to prepare Sample No. 2 for an adhesion test between the primer layer and the decorative layer.
3. For the transparency, pencil hardness, and winding applicability tests, the primer layer coating was applied to one side of the polymethyl methacrylate film with a bar coater, dried in hot air at 90 ° C. for 1 minute, and the coating thickness was 0.3 μm. A primer layer is formed, and then the hard coat layer paint is applied to the back surface with a bar coater, dried with hot air at 80 ° C. for 1 minute, and then cured with an ultraviolet light quantity of 450 mJ / m ² , and a coating thickness of 3 μm. A hard coat layer was formed.
4). For the elongation test, the primer layer paint described above was applied to one side of a 125 μm-thick biaxially stretched polyethylene terephthalate film film “Lumirror U463 (trade name)” (manufactured by Toray Industries Inc.) with a bar coater. Dry with hot air for a minute to form a primer layer with a coating thickness of 0.3 μm, then apply the above hard coat layer paint on the back with a bar coater, dry with hot air at 80 ° C. for 1 minute, and then apply an ultraviolet light quantity of 450 mJ / M ² to form a hard coat layer with a coating thickness of 3 μm.

[Example 2]
A molding hard coat film was prepared in the same manner as in Example 1 except that the blending ratio of the vinyl chloride-vinyl acetate copolymer resin “Solvine C” used in the primer layer coating material and the polymethyl methacrylate resin was changed to 80/20. Produced.
[Example 3]
A molding hard coat film was prepared in the same manner as in Example 1 except that the blending ratio of the vinyl chloride-vinyl acetate copolymer resin “Solvine C” used for the primer layer coating material and the polymethyl methacrylate resin was changed to 25/75. Produced.

[Example 4]
A molding hard coat film was produced in the same manner as in Example 1 except that the coating thickness of the primer layer was changed to 0.1 μm.
[Example 5]
A hard coat film for molding in the same manner as in Example 1 except that a 75 μm thick polyethylene terephthalate film “Diafoil O300E (trade name)” (manufactured by Mitsubishi Chemical Polyester Film Co., Ltd.) was used instead of the polymethyl methacrylate film. Was made.

[Example 6]
Hard coating for molding in the same manner as in Example 1 except that a 125 μm thick polycarbonate film “Panlite PC-2151 (trade name)” (manufactured by Teijin DuPont Films Ltd.) was used instead of the polymethyl methacrylate film. A film was prepared.
[Example 7]
Except for changing the vinyl chloride-vinyl acetate copolymer resin “Solvine C” used for the primer layer paint to the same type “Solvine TA3 (trade name)” (glass transition point 65 ° C., manufactured by Nissin Chemical Industry Co., Ltd.) A molding hard coat film was produced in the same manner as in Example 1.

[Example 8]
Spherical silica “MEK-ST-ZL (trade name)” (solid content 30%, particle size 0.085 μm, manufactured by Nissan Chemical Co., Ltd., toluene / ethyl acetate = 50/50) mixed with primer layer paint A hard coating film for molding was prepared in the same manner as in Example 1 except that 2 parts of fine particle dispersion was added by adding glass beads in a solvent.
[Example 9]
In the primer layer coating, amorphous silica “Sea Hoster KE-S50 (trade name)” (solid content 15%, particle size 0.50 μm, manufactured by Nippon Shokubai Co., Ltd., toluene / ethyl acetate = 50/50) A molding hard coat film was prepared in the same manner as in Example 1 except that 2 parts of fine particle dispersion was added by adding glass beads.

[Example 10]
To the primer layer coating material, spherical silica “MEK-ST-2040 (trade name)” (solid content 40%, particle size 0.20 μm, manufactured by Nissan Chemical Co., Ltd.) as an inorganic fine particle is added 2 parts of a fine particle dispersion. A molding hard coat film was produced in the same manner as in Example 1 except that the thickness was changed to 0.1 μm.
[Example 11]
A molding hard coat film was produced in the same manner as in Example 10 except that the coating thickness of the primer layer of Example 10 was changed to 1.0 μm.

[Example 12]
Example 1 was used except that the above-mentioned spherical silica “MEK-ST-2040” was used as the inorganic fine particles in the primer layer coating, and the mixing ratio of the thermoplastic resin and the inorganic fine particles was set to 99.8 / 0.2. Thus, a hard coat film for molding was produced.
[Example 13]
A molding hard coat film was produced in the same manner as in Example 12 except that the mixing ratio of the thermoplastic resin and the inorganic fine particles was 95/5.

[Comparative Example 1]
A molding hard coat film was produced in the same manner as in Example 1 except that the vinyl chloride-vinyl acetate copolymer resin “Solvine C” was used alone as the primer layer coating.
[Comparative Example 2]
A molding hard coat film was produced in the same manner as in Example 1 except that the polymethyl methacrylate resin “Acryt 0404EA-P” was used alone as the primer layer coating.

[Comparative Example 3]
A molding hard coat film was prepared in the same manner as in Example 1 except that the blending ratio of the vinyl chloride-vinyl acetate copolymer resin “Solvine C” used for the primer layer coating material and the polymethyl methacrylate resin was changed to 85/15. Produced.
[Comparative Example 4]
A molding hard coat film was prepared in the same manner as in Example 1 except that the blending ratio of the vinyl chloride-vinyl acetate copolymer resin “Solvine C” used for the primer layer coating material and the polymethyl methacrylate resin was changed to 20/80. Produced.

The following items were evaluated for the molding hard coat films of Examples and Comparative Examples produced as described above, and the results are summarized in Table 1 below. In Table 1, the vinyl chloride-vinyl acetate copolymer resin is represented as “PVC”, and the polymethyl methacrylate resin as “PMMA”.
(1) A 3 cm square absorbent cotton is placed on the solvent-resistant primer layer coating, and a mixed solvent “NPR / toluene / ethyl acetate / MEK = 30/30/20/20 (parts by weight)” is dropped on the absorbent cotton. Then, after the solvent test for 3 minutes, the absorbent cotton was removed, the surface state of the primer layer was visually observed, and the surface state of each sample was evaluated in three stages. The evaluation criteria are as follows. In addition, (circle) and (circle) evaluation product determined that solvent resistance was a pass.
Evaluation criteria ◎: No change ○: Slightly whitened △: Fully whitened ×: Dissolved (2) Heat resistance Using a film on which a primer layer is formed, folded so that the primer layer faces each other, thermal gradient tester HG-100 -2 "Toyo Seiki Co., Ltd.", pressure was applied at 3 kg / cm ² , time 10 seconds, the pressure-bonding surface was peeled off, and the temperature without surface roughness was defined as the heat resistant temperature. In addition, the heat-resistant temperature of 70 degreeC or more was determined to be acceptable.

(3) Adhesion adhesion test sample No. 1 primer layer and No. 2 decoration layer are 1 mm using a cross-cut peel test jig under constant temperature and humidity conditions (23 ° C., 53% RH). 100 crosscuts of No. ² were prepared, adhesive tape No. 252 made by Sekisui Chemical Co., Ltd. was applied on it, pressed uniformly with a spatula, then peeled in the direction of 90 degrees, and the remaining number of each layer was divided into 4 levels. evaluated. The evaluation criteria are as follows, and ◎ and ○ evaluation products were judged to have passed. In addition, the item “PR layer” in Table 1 is an evaluation result of adhesion between the primer layer and the base film, and “decoration layer” is an evaluation result of adhesion between the primer layer and the decoration layer.
Evaluation criteria ◎: 100 pieces ○: 99 to 95 pieces △: 94 to 50 pieces ×: 49 to 0 pieces

(4) Transparency The total light transmittance of each molding hard coat film prepared in each Example and Comparative Example was measured by the test method shown in JIS K7136. The evaluation criteria are as follows, and ◎ and ○ evaluation products were judged to have passed transparency.
Evaluation criteria A: 92% or more B: 91% or more and less than 92% X: less than 91% (5) Elongation Using the above-described film for elongation test, a test piece having a size of 15 mm and a length of 150 mm is prepared. The sample was pulled at a pulling rate of 50 mm / min and a distance between chucks of 100 mm, and the tensile elongation until cracking occurred in the hard coat layer on the surface was measured.

(6) Pencil hardness About each molding hard coat film produced in each Example and Comparative Example, pencil hardness was measured by the test method shown in JIS K5600. The hardness without scratches on the surface was indicated.
(7) Winding suitability About each molding hard coat film produced in each example and comparative example, each sample was cut into 10 cm squares, and two sets of samples were prepared by superimposing the primer layer surface and the hard coat layer surface, After storage for 48 hours in an environment at a temperature of 40 ° C., the sample was taken out, and evaluated according to four levels based on the pressure state of the front and back surfaces and the surface state of each surface when the sample was peeled. The evaluation criteria are as follows, and the applicability of winding up ◎ and ○ evaluation products was determined to be acceptable.
Evaluation criteria ◎: Crimping, no surface roughness ○: Crimping slightly, but no surface roughness △: Strong crimping, no surface roughness ×: Strong crimping, large surface roughness

As is apparent from the results of Table 1 above, according to the examples of the present invention, the primer layer is excellent in adhesion between the base film and the decorative layer, and the moldability (elongation), hardness ( In addition to pencil hardness and winding ability, a molding hard coat film excellent in solvent resistance, heat resistance and transparency can be obtained.
On the other hand, in Comparative Examples 1 and 2 in which either the vinyl chloride-vinyl acetate copolymer resin or the polymethyl methacrylate resin was used alone as the resin component of the primer layer, the adhesion with the decorative layer was particularly bad, In Comparative Example 1, good characteristics cannot be obtained with respect to the solvent resistance and heat resistance of the primer layer.

Moreover, although a vinyl chloride-vinyl acetate copolymer resin and a polymethyl methacrylate resin are used in combination as the resin component of the primer layer, good results cannot be obtained in Comparative Examples 3 and 4 in which the blending ratio is outside the scope of the present invention. . That is, in Comparative Example 3 in which the mixing ratio of the vinyl chloride-vinyl acetate copolymer resin is more than 80 parts by weight, the solvent resistance of the primer layer is lowered, so the solvent contained in the paint (ink) forming the decorative layer is used. The primer layer coating is eroded and the decorating properties and adhesion are reduced. Moreover, problems such as pressure bonding or blocking occur when the film for molding is wound up.
Moreover, in the comparative example 4 with the compounding ratio of vinyl chloride-vinyl acetate copolymer resin being less than 25 parts by weight, the adhesion with the decorative layer is particularly lowered.

DESCRIPTION OF SYMBOLS 1 Base film 2 Primer layer 3 Decorating layer 4 Hard coat layer 5 Hard coat film for molding

Claims (7)

  In a hard coat film for molding, in which a decorative layer is formed on one surface of a base film via a primer layer and a hard coat layer is formed on the other surface, the primer layer is made of vinyl chloride-vinyl acetate. A polymerization resin and a polymethyl methacrylate resin are contained, and a blending ratio (parts by weight) of the vinyl chloride-vinyl acetate copolymer resin and the polymethyl methacrylate resin is in a range of 80/20 to 25/75. Hard coat film for molding.   The hard coat film for molding according to claim 1, wherein the vinyl chloride-vinyl acetate copolymer resin has a glass transition temperature (Tg) of 65 ° C or higher.   The hard coat film for molding according to claim 1 or 2, wherein the primer layer contains inorganic or organic fine particles.   The hard coat film for molding according to any one of claims 1 to 3, wherein the primer layer has a thickness in the range of 0.1 µm to 1.0 µm.   The hard coat film for molding according to any one of claims 1 to 4, wherein the hard coat layer contains an ionizing radiation curable resin.   The hardt film for molding according to any one of claims 1 to 5, wherein the substrate film is a polyethylene terephthalate film, a polycarbonate film, or a polymethyl methacrylate film. A primer layer coating containing a vinyl chloride-vinyl acetate copolymer resin and a polymethyl methacrylate resin in a blending ratio (parts by weight) in the range of 80/20 to 25/75 is applied to one surface of the base film. After drying, the other surface is coated with a coating for a hard coat layer containing an ionizing radiation curable resin, dried, subjected to photocuring treatment with ionizing radiation, and then decorated on the primer layer. A method for producing a hard coat film for molding, comprising forming a layer.

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