JP2001205726A - Transparent plastic film having hard coat layer and plastic molding provided with hard coat layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plastic film with a hard coat layer which is used on the occasion of making a plastic molding with the hard coat layer by an injection molding method and wherein no cracking occurs after molding. SOLUTION: In this transparent plastic film with the hard coat layer, no cracking occurs in the hard coat layer when the film is subjected to a tensile test under the conditions of a temperature of 22 deg.C, one side being fixed and an elastic stress rate of 20 mm/min., in respect to the region satisfying the relations y<5.7 in x<=100, y<-0.018x+7.5 in 100<=x<=150, y<-0.008x+6.0 in 150<=x<=200, y<-0.005x+5.4 in 200<=x<=300, y<-0.003x+4.8 in 300<=x<=400, y<-0.002x+4.4 in 400<=x<=500 and y<3.4 in 500<=x, where the thickness of a plastic base film is denoted by x (μm) and an elongation in the test under the above conditions by y (%).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent plastic film having a hard coat layer on one side, and more particularly, to a use of various industrial materials and a polycarbonate molded article provided with a hard coat layer by an injection molding method (for example, , A substrate, etc.) with a hard coat layer. Further, the present invention relates to a plastic molded article in which a transparent plastic film having the hard coat layer is laminated and integrated, and the hard coat layer is provided on the surface. Furthermore, the present invention relates to a display cover, a nameplate or a packaging container made of a transparent plastic film having the hard coat layer.

[0002]

2. Description of the Related Art Conventionally, plastic molded articles made of acrylic resin, polystyrene resin, polycarbonate resin, and other synthetic resins have good moldability, excellent transparency, light weight, low cost, and the like. It has advantages and is widely used as various industrial materials, building materials, decorative materials, optical materials, household materials and the like.

[0003] On the other hand, plastic molded articles have poor surface scratch resistance due to their lower surface hardness as compared with glass, metal, etc., and are liable to be scratched on the surface and have reduced transparency.
There are problems such as increased contamination. for that reason,
It is necessary to increase the surface hardness of the plastic molded article to improve the scratch resistance.

[0004] As one method for improving the scratch resistance of a plastic molded product, a hard coat layer made of a hard coat material is formed on the surface of the plastic molded product to improve the surface hardness.

[0005] Hard coat materials include epoxy resin-based, acrylic resin-based, amino resin-based, and polysiloxane-based materials. The hard coat layer is formed by dissolving the hard coat material composition in an appropriate solvent and applying a hard coat having a thickness of several μm to several tens μm by a coating method such as spray coating or dip coating on the surface of the molded article. This is performed by forming a film and then curing the film by means such as heating or ultraviolet irradiation.

However, although this method can improve the surface hardness of a resin molded product, it is not preferable from the viewpoint of industrial production. The reasons are as follows. The formation of the hard coat layer must be performed for each molded product, and the production efficiency is low. Even in the case of obtaining a plate-like molded product such as a window of an automobile or the like, continuous production is difficult, and a single-wafer method in which coating and curing are performed one by one for each formed substrate is inevitable. Coating means such as spray coating and dip coating do not provide a uniform film thickness, resulting in uneven surface hardness of the product. In dip coating when a hard coat layer is formed on only one surface of a molded product (for example, only one surface of a substrate), the non-coated portion must be masked. A great deal of expense is required to transport the molded article on which the hard coat layer is to be formed. In the case of a heat treatment type hard coat material, a dimensional change occurs due to warpage or torsion caused by molecular orientation or residual stress existing in a plastic molded product produced by injection molding, and cracks occur.

[0007] In order to solve these problems, a method has been considered in which a plastic film provided with a hard coat layer in advance is used for injection molding of a plastic molded product. This means that the plastic film to which the hard coat layer has been previously applied is placed such that the hard coat layer faces one mold surface of the mold of the injection molding machine, that is, the hard coat layer is positioned on the intended outer surface of the final molded product. So that
Next, the mold is closed, a molten resin is injected from a nozzle into a cavity between the base surface of the plastic film and the other mold surface of the mold, cooled, and molded. If the plastic film and the molten resin are of the same type or of the same type, they are compatible at the interface and are completely integrated. In this method, a final molded article to which the hard coat layer has been applied simultaneously with the injection molding can be obtained.

Further, in this method, two plastic films to which a hard coat layer is applied in advance are used so that each hard coat layer faces one mold surface and the other mold surface of the mold, that is, a hard coat layer is formed. A hard coat layer is applied to both outer surfaces of the final plate-shaped product by a single integration process by mounting the coating layer so that it is located on the intended outer surfaces of the final plate-shaped product and performing injection molding. It is also possible. This method is disclosed in Japanese Patent Publication No. Hei 1-47284, Japanese Patent Publication No. Hei 4-9648 and Japanese Patent Publication No. Hei 4-9649.
Reference is made to US Pat.

[0009]

However, there is a quality problem that must be solved by this method. This is a problem of cracking (cracking) in the hard coat layer after molding.

The temperature of the molten resin used during injection molding is high (for example, 310 to 320 in the case of polycarbonate).
° C), the temperature of the hard coat layer also becomes high through the plastic film. At this time, since the hard coat layer has already been crosslinked and cured, it cannot follow the elongation of the plastic film. In addition, in the process of cooling from a high temperature state to a normal temperature, the hard coat layer and the plastic film or the molten resin have significantly different shrinkage rates, and thus it is considered that the hard coat layer is cracked.

In order to solve this problem, a method of increasing the thickness of the plastic film to minimize the temperature applied to the hard coat layer during injection molding is considered. However, for that purpose, the thickness of the plastic film needs to be about 500 μm or more. Since it takes a great deal of effort to successfully roll a plastic film having a thickness of more than 500 μm into a roll, it is difficult to form a hard coat layer on such a thick plastic film by a continuous method, and a single-wafer method is required. It must be made. That is, at the time of preparing the plastic film with the hard coat layer, the same problem as the case where the hard coat layer is directly applied to the molded article substrate occurs.

On the other hand, Japanese Patent Application Laid-Open No. H11-70606 discloses a plastic film provided with a hard coat layer, which is used for a touch panel of an electric product, and has a pencil hardness of 2H or more. In addition, a hard coat film that does not crack when the curvature is 10 mm or more in a mandrel test is described. However, the publication does not consider the elongation percentage of the hard coat layer at all.

Accordingly, an object of the present invention is to provide a transparent plastic film having a hard coat layer on one surface, more specifically, a hard plastic layer provided with a hard coat layer by an injection molding method. An object of the present invention is to provide a plastic film having a hard coat layer which does not cause cracks in a hard coat layer after molding. In particular, an object of the present invention is to provide a polycarbonate film with a hard coat layer for obtaining a polycarbonate molded article provided with a hard coat layer by an injection molding method.

It is another object of the present invention to provide a plastic molded article in which a transparent plastic film having the hard coat layer is laminated and integrated, and the surface of which is provided with the hard coat layer.

Still another object of the present invention is to provide a display cover, a nameplate or a packaging container formed by using the transparent plastic film having the hard coat layer.

[0016]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the occurrence of cracks in the hard coat layer after molding is related to the elongation of the hard coat layer at room temperature (22 ° C.). . Then, the plastic base film thickness x and the elongation percentage y when the plastic film with the hard coat layer is pulled under specific conditions are examined in further detail.
In a region where satisfies a specific relationship, a plastic film with a hard coat layer that does not crack in the hard coat layer has been found to be free from cracks even after molding, and has reached the present invention.

That is, the present invention provides a transparent plastic film having a hard coat layer on one side of a plastic base film, wherein the thickness of the base film is x (μ
m), the plastic film having the hard coat layer was fixed at 22 ° C. on one side, and the pulling speed was 20 mm / m.
The elongation percentage when pulled under the condition of in is represented by y (%). When x ≦ 100, y <5.7 When 100 ≦ x ≦ 150, y <−0.018x +
7.5 When 150 ≦ x ≦ 200, y <−0.008x +
6.0 When 200 ≦ x ≦ 300, y <−0.005x +
5.4 When 300 ≦ x ≦ 400, y <−0.003x +
4.8 When 400 ≦ x ≦ 500, y <−0.002x +
In a region satisfying the relation of y <3.4 in the case of 4.4 500 ≦ x, the transparent plastic film having a hard coat layer does not cause cracks in the hard coat layer when the tensile test is performed under the above conditions. .

FIG. 1 shows the base film thickness x (μm).
3 is a graph showing the relationship between the elongation percentage y (%) of a tensile test of the plastic film with a hard coat layer. That is, in the graph, a straight line AB and a straight line B-
C, straight line CD, straight line DE and straight line EF are respectively: AB: 100 ≦ x ≦ 150, y = −0.01
8x + 7.5 BC: When 150 ≦ x ≦ 200, y = −0.00
8x + 6.0 CD: y = −0.00 at 200 ≦ x ≦ 300
5x + 5.4 DE: When 300 ≦ x ≦ 400, y = −0.00
3x + 4.8 EF: 400 ≦ x ≦ 500, y = −0.00
2x + 4.4. In the transparent plastic film having the hard coat layer of the present invention, cracks occur in the hard coat layer in the lower area (the shaded area) of the graph in FIG. do not do.

In the present invention, the plastic base film is preferably a polycarbonate film. In the present invention, the transparent plastic film having the hard coat layer is preferably wound into a roll from the viewpoint of production efficiency. In the present invention,
The plastic base film preferably has a thickness of 100 μm to 500 μm from the viewpoint of production efficiency.

The plastic film with a hard coat layer of the present invention is suitably used for any of display covers, nameplates and packaging containers.

When the plastic film with a hard coat layer of the present invention is used to produce a plastic molded article by injection molding, a transparent plastic film having a hard coat layer on one side of a plastic base film, and a hard coat layer having an injection mold. The mold is set so as to face one of the mold surfaces, the mold is clamped so that a cavity is formed between the base surface of the film and the other mold surface, and then the molten resin is injected into the cavity. Then, it is preferably used for cooling and molding the molded article main body, and laminating and integrating the plastic film on the surface of the molded article main body to obtain a molded article provided with a hard coat layer.

The plastic film with a hard coat layer of the present invention is used for producing a plastic plate-like molded product by injection molding, wherein two transparent plastic films each having a hard coat layer on one side of a plastic base film are hard-coated. Set so that the layers face one mold surface and the other mold surface in the injection mold,
The mold is clamped so that a cavity is formed between the base surfaces of the two films, and then the molten resin is injected into the cavity, cooled, and the molded product body is molded. It is preferably used for laminating and integrating the plastic film on both sides to obtain a plate-like molded product having a hard coat layer on both sides.

The present invention is also a plastic molded article in which the transparent plastic film having the hard coat layer is laminated and integrated, and the hard coat layer is provided on the surface.

Examples of such molded articles include windows of automobiles such as passenger cars and buses, windows of trains and airplanes, show windows, transparent plates for sun terraces, and sunroofs of automobiles. The transparent plastic film with a hard coat layer of the present invention can be applied to the molded article of the present invention.

Further, the present invention is a display cover, a nameplate or various packaging containers made of a transparent plastic film having the hard coat layer. Examples of the display cover include a display cover for OA equipment. Examples of the packaging container include a food packaging container and the like, and the packaging container also includes a can juice can displayed on a window as a product sample in a can juice vending machine.

[0026]

FIG. 2 is a sectional view of a transparent plastic film having a hard coat layer according to the present invention. Transparent plastic film with hard coat layer of the present invention (1)
Has a hard coat layer (1b) on one side of a plastic base film (1a).

Examples of the material of the plastic base film (1a) include polycarbonate resin, polyester resin, polyamide resin, polyimide resin, acrylic resin, and polystyrene resin, which are excellent in transparency, lightweight and excellent in impact resistance. Therefore, a polycarbonate resin is preferable. Also, when the molded article body is made of a polycarbonate resin such as an automobile window, the polycarbonate resin is preferable as the material of the plastic base film in consideration of the integration of the molded article body and the base film. If the material of the molded article main body and the material of the base film are the same or have a similar structure that is easily compatible with each other, it is preferable because they are compatible and integrated at the time of injection molding.

The hard coat layer (1b) is formed by applying a hard coat material composition on a plastic base film (1a), drying and curing. As the hard coat material, there is a thermosetting hard coat material such as a silicone-based or melamine-based material, but from the viewpoint of productivity such as curing reactivity, an ultraviolet-curable hard coat material is more preferable. As the ultraviolet-curable hard coat material, a radical polymerizable hard coat material such as an unsaturated polyester resin or an acrylic resin, or a cationic polymerizable hard coat material such as an epoxy resin or a vinyl ether resin can be used. Considering the curing reactivity and the surface hardness, an acrylic radical polymerizable hard coat material is desirable.

The acrylic radical polymerizable hard coat material is mainly composed of a polyfunctional (meth) acrylate having two or more (meth) acryloyl groups in a molecule and a photopolymerization initiator.

Examples of the polyfunctional (meth) acrylate include 1,6-hexanedi (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, and neopentyl glycol diacrylate. Bifunctional (meth) acrylates such as (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, glycerol tri (meth) acrylate, tris- (2-hydroxyethyl) -isocyanurate ( Examples thereof include trifunctional (meth) acrylates such as meth) acrylate, and tetrafunctional or higher (meth) acrylates such as pentaerythritol tetra (meth) acrylate and dipentaerythritol hexa (meth) acrylate.

Of these, for example, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and the like are preferable because high hardness can be obtained. One of these may be used alone, or two or more thereof may be used in combination. The amount of the polyfunctional (meth) acrylate used is about 20 to 80% by weight (solid basis) in the hard coat material.

Further, in addition to the above polyfunctional (meth) acrylate, a photopolymerizable oligomer or polymer can be used. For example, it is an oligomer or a polymer having a (meth) acryloyl group at a terminal, and has a weight average molecular weight Mw of, for example, about 1,000 to 50,000. Examples of the oligomer or polymer portion include a urethane polymer, an epoxy polymer, a polyester polymer, a styrene polymer, a styrene / acrylonitrile copolymer, a styrene / (meth) acrylate copolymer,
Examples thereof include those formed from (meth) acrylate polymers, butadiene polymers, and silicone polymers. Examples of the photopolymerizable oligomer or polymer include urethane (meth) acrylate obtained by reacting a polyhydric alcohol, a polyvalent isocyanate, and a hydroxyl group-containing (meth) acrylate, a polyhydric alcohol and a polycarboxylic acid and / or Polyester (meth) acrylate obtained by esterifying anhydride and (meth) acrylic acid,
Epoxy (meth) obtained by reacting (meth) acrylic acid with a compound having two or more epoxy groups in the molecule
Acrylate, polystyryl (meth) acrylate, polybutadiene (meth) acrylate and the like can be mentioned.

Various known photopolymerization initiators can be used. For example, ketones (acetophenone,
Propiophenone, anthraquinone, thioxanthone,
It may be selected from benzophenone or a derivative thereof), benzoic acid esters (for example, methyl p-dimethylaminobenzoate), benzoin ether or a derivative thereof (for example, benzoin methyl ether, benzoin ethyl ether), and acylphosphine oxide. Of course, other than these may be used. The amount of the photopolymerization initiator used is, for example, the above-mentioned polyfunctional (meth) acrylate (A) 1
0.1 to 30 parts by weight, preferably 1 to 100 parts by weight
It can be selected from a range of about to 20 parts by weight.

The organic solvent for diluting the hard coat material can be used without any limitation as long as the material constituting the hard coat material is soluble. For example, as an organic solvent, alcohols such as ethyl alcohol, n-propyl alcohol, isopropyl alcohol and n-butyl alcohol, ketones such as methyl ethyl ketone (MEK), methyl isobutyl ketone and cyclohexanone, ethyl acetate, butyl acetate, toluene and dibutyl Examples thereof include hydroxytoluene, xylene, 2-methoxyethanol, 2-ethoxyethanol, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, methyl cellosolve, ethyl cellosolve, and dibutyl malate. The organic solvent may be used alone, but two or more kinds are often used in combination in consideration of the adhesion of the hard coat layer to the plastic base film, the hardness of the hard coat layer, and the like.

The mixing ratio of the ultraviolet-curable hard coat material and the organic solvent in the hard coat material composition is usually 20% based on the total composition.
About 80% by weight and about 20 to 80% by weight of an organic solvent.
What is necessary is just to determine so that the favorable solubility and suitable viscosity (application suitability) of a hard-coat material may be obtained.

Further, the hard coat material composition may contain various known additives such as an ultraviolet absorber, an ultraviolet stabilizer, an antioxidant, and a thermal polymerization inhibitor, if necessary.

The hard coat material composition is a polyfunctional (meth)
A hard coat material component such as an acrylate and a photopolymerization initiator can be obtained by dispersing or dissolving in the above-mentioned specific organic solvent by an ordinary method.

In order to obtain the plastic film with a hard coat layer of the present invention, from the viewpoint of production efficiency, the hard coat material composition is continuously applied to a long plastic base film wound into a roll, dried and cured. And then
A method of winding in a roll shape is preferred.

The continuous coating of the hard coat material composition may be performed by a bar coating method, a doctor blade method, a reverse coating method,
It can be performed by a known method such as a Meyer bar coating method, a gravure coating method, a comma coating method, and a slit die coating method.

The drying after the application may be performed, for example, in a temperature range of 50 to 120 ° C., for example, for about 10 seconds to 5 minutes.
After drying, it is irradiated with ultraviolet rays and cured. Ultraviolet irradiation, a xenon lamp, a low pressure mercury lamp, medium pressure mercury lamps, high pressure mercury lamp, ultra-high pressure mercury lamp, a metal halide lamp, a carbon arc lamp, using a lamp such as a tungsten lamp, ultraviolet rays may be irradiated about 200~2000mJ / cm ^2. After curing, the film on which the hard coat layer is formed is wound into a roll.

Although the degree varies depending on the type of the hard coat material, the curing generally proceeds more when the irradiation amount of the ultraviolet ray is increased. Therefore, when the tensile test is performed, cracks tend to occur at a lower elongation y.

The plastic base film has a thickness of 10
It is preferably from 0 μm to 500 μm, and the film thickness is 200 μm
Those having a thickness of from 400 μm to 400 μm are more preferred. When the thickness is less than 100 μm, when the film with the hard coat layer is mounted on an injection mold, the film is wrinkled and workability is deteriorated. On the other hand, in the case of a film having a thickness of more than 500 μm, more labor is required when the base film is transported at the time of coating or when it is wound into a roll.

As shown in FIG. 1, as the thickness x of the plastic base film increases, even if cracks occur at a lower elongation y in the tensile test, the requirements of the present invention are satisfied. You will get. As the thickness of the base film increases, the temperature applied to the hard coat layer is reduced when the plastic film with the hard coat layer is used for injection molding, so that the elongation y at the time of crack generation in the tensile test is low. Can also meet practical performance.

The thickness of the hard coat layer is usually about 0.5 μm to 20 μm after curing, preferably 2 μm to 15 μm.
m. As the thickness of the hard coat layer increases, cracks tend to occur at a lower elongation y when the tensile test is performed.

In a region satisfying the requirements of the present invention, that is, in a hatched region of the graph of FIG. 1, a plastic film with a hard coat layer which does not crack in the hard coat layer when a tensile test is performed under the above conditions. Can be obtained as follows. The absolute hardness of each hard coat material differs depending on the hard coat material used. The harder the hard coat layer, the more difficult it is to follow the elongation of the plastic base film. First, the hardness unique to the hard coat material is considered.

As described above, as the irradiation amount of the ultraviolet ray during the formation of the hard coat layer increases and the thickness of the hard coat layer increases, cracks occur at a lower elongation y when the tensile test is performed. On the contrary, as the thickness x of the plastic base film increases,
When the tensile test is performed, even if a crack occurs at a lower elongation percentage y, the requirement of the present invention tends to be satisfied. By considering and adjusting these conditions, a plastic film with a hard coat layer satisfying the requirements of the present invention can be obtained.

Next, with reference to FIGS. 3, 4, 5 and 6, the use of the plastic film with a hard coat layer of the present invention in an injection molding method will be described. FIG. 3 is a sectional view showing a state in which the injection molding die is clamped, and FIG.
FIG. 4 is a sectional view showing a layer structure of a molded article provided with a hard coat layer obtained by injection molding in FIG. 3. FIG.
It is a cross-sectional view showing a state in which the injection molding die is clamped,
FIG. 6 is a cross-sectional view showing a layer structure of a molded product obtained by injection molding of FIG. 5 and having a hard coat layer provided on both surfaces.

In FIG. 3, the plastic film (1) with a hard coat layer of the present invention is set so that the hard coat layer (1b) faces the movable mold (3) of the injection mold.
The mold is clamped so that a cavity (5) is formed between the film base surface (1a) and the fixed mold (4) surface. afterwards,
The molten resin is injected into the cavity (5) from the gate (6) by a conventional method and cooled.

By this operation, as shown in FIG. 4, at the same time as the molded article main body (2) is formed, the plastic film (1) is laminated and integrated on the surface of the molded article main body (2). A molded article provided with the coat layer (1b) is obtained. At this time, the material of the molten resin to be injected and the material of the base film (1a) constituting the molded article main body (2) are preferably compatible with each other, particularly preferably the same material. Due to the heat during injection molding, the cavity of the base film (1a)
(5) The surface on the side is melted and welded, and is firmly integrated with the molded article body (2). After molding, the two molds (3) and (4) are opened, the molded product is taken out, and necessary parts are trimmed to obtain a finished product.

By using the plastic film (1) with a hard coat layer of the present invention, cracks do not occur in the hard coat layer regardless of heat during injection molding and cooling from a high temperature state to a normal temperature.

FIG. 5 shows a case where a molded article having a hard coat layer provided on both sides is manufactured, and two plastic films with a hard coat layer of the present invention are used. In FIG. 5, a plastic film with a hard coat layer (1)
The movable mold (7) and the fixed mold (8) are set so that the hard coat layers (1b) and (1b) face the movable mold (7) surface and the fixed mold (8) surface of the injection mold, respectively. ) And the slide mold (9), and set them. The mold is clamped so that a cavity (10) is formed between the film base surfaces (1a) and (1a). Thereafter, the molten resin is injected into the cavity (10) from the gate (11) by a conventional method, and cooled.

By this operation, as shown in FIG. 6, at the same time as the molded article main body (2) is formed, the plastic films (1) and (1) are laminated and integrated on both surfaces of the molded article main body (2). Thus, a molded article having the hard coat layers (1b) and (1b) provided on both surfaces is obtained. After molding, the molds (7), (8) and (9) are opened, the molded product is taken out, and necessary parts are trimmed to obtain a finished product.

The use of the plastic film (1) (1) with a hard coat layer of the present invention prevents cracks in the hard coat layer despite the heat during injection molding and cooling from a high temperature state to room temperature. There is no. In this way, it is possible to obtain a molded article having a hard coat layer provided on both sides. Further, if the hard coat layers in the two films (1) and (1) used are different within the scope of the present invention, a hard coat layer having different characteristics on both surfaces of the molded article body (2) may be provided. Is also possible. For example, in the case of an automobile window, an optimal hard coat layer can be provided on the outside of the window and on the inside of the vehicle.

As described above, a plastic molded article having the hard coat layer provided on the surface of the present invention can be obtained.

[0055]

EXAMPLES The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples. In the following, “parts” indicating amounts indicate parts by weight unless otherwise specified.

Example 1 (Plastic base film) A polycarbonate film having a width of 12 cm and a thickness of 100 μm produced by extrusion was used. (Hard coat material composition A) Photopolymerizable monomer: 4 parts of pentaerythritol triacrylate 10 parts of pentaerythritol tetraacrylate Photopolymerizable oligomer: 13 parts Urethane acrylate (having a molecular weight of about 1,000 to 2,000) Photopolymerization initiator: Irgacure 184 (manufactured by Ciba Geigy) 3 parts MEK / toluene / butyl acetate / isopropyl alcohol = 1/1/1/1 (weight ratio) 70 parts The above were mixed and dissolved to obtain an ultraviolet curable resin composition A.

The above composition was applied to the above-mentioned polycarbonate film having a thickness of 100 μm by the Meyer bar coating method, dried, and then irradiated with ultraviolet light from a high-pressure mercury lamp (irradiation amount: 3).
(00 mJ / cm ² ), and cured to form a hard coat layer having a thickness of 5 μm and wound up in a roll. Thus, a transparent polycarbonate film with a hard coat layer was obtained.

(Tensile Test) The obtained polycarbonate film with a hard coat layer was cut into a size of 15 cm × 1 cm and mounted on Tensilon so that the chucking width of the sample was 10 cm. Next, the lower chucking portion was fixed, and the upper chucking portion was pulled upward at a speed of 20 mm / min, and it was observed how much the film stretched to cause cracks in the hard coat layer. Cracks were observed using a magnifying glass of 10 times. The tensile test was performed at 22 ° C. The elongation at the time of occurrence of cracks of the polycarbonate film with a hard coat layer of Example 1 was 8.2%.

(Injection molding) The obtained polycarbonate film with a hard coat layer was cut into a size of 10 cm × 20 cm. Referring to FIG. 3, this film was mounted on injection molding dies (3) and (4) such that the hard coat layer (1b) was on the upper side, and the mold was clamped. Next, injection molding was performed at a molten polycarbonate resin temperature of 315 ° C., a mold temperature of 80 ° C., and a molding time of 30 sec including a filling time and a cooling time of the molten polycarbonate resin to obtain a molded product substrate having a hard coat layer provided on one surface. Was. The occurrence of cracks in the hard coat layer after molding was visually observed and observed using a 10-fold magnifying glass. When the polycarbonate film with a hard coat layer of Example 1 was used, no crack occurred in the hard coat layer after molding.

The following Examples 2 to 24 and Comparative Examples 1 to 12
In the same manner as in Example 1, the polycarbonate film with a hard coat layer obtained in the above was subjected to a tensile test to determine the elongation when cracks occurred. In addition, injection molding was performed in the same manner as in Example 1, and the occurrence of cracks in the hard coat layer after molding was evaluated.

Example 2 The same procedure as in Example 1 was carried out except that a polycarbonate film having a thickness of 150 μm was used. Example 3 The same procedure as in Example 1 was performed except that a polycarbonate film having a thickness of 200 μm was used. Example 4 The same procedure as in Example 1 was carried out except that a polycarbonate film having a thickness of 300 μm was used. Example 5 The same procedure as in Example 1 was carried out except that a polycarbonate film having a thickness of 400 μm was used. Example 6 The same procedure was performed as in Example 1 except that a polycarbonate film having a thickness of 500 μm was used.

Example 7 The same procedure as in Example 1 was carried out except that the coating amount of the hard coat material composition A was changed to change the thickness of the hard coat layer to 3 μm. Example 8 The same procedure as in Example 1 was carried out except that the coating amount of the hard coat material composition A was changed to change the thickness of the hard coat layer to 10 μm.

[Embodiment 9] The irradiation amount of ultraviolet rays was 1000 mJ.
/ Cm ^2, but in the same manner as in Example 8. [Comparative Example 1] The same operation as in Example 9 was performed except that the coating amount of the hard coat material composition A was changed and the thickness of the hard coat layer was changed to 15 µm.

Example 10 (Hard coat material composition B) Photopolymerizable monomer: 8 parts of dicyclopentanyl acrylate 9 parts of pentaerythritol triacrylate 7 parts of pentaerythritol tetraacrylate 3 parts of 1,6-hexanediol diacrylate Photopolymerization initiator: Irgacure 907 (manufactured by Ciba Geigy) 3 parts Toluene / isopropyl alcohol = 1/1 (weight ratio) 70 parts The above were mixed and dissolved to obtain an ultraviolet curable resin composition B. The procedure was performed in the same manner as in Example 2 except that the hard coat material composition B was used instead of the hard coat material composition A.

Example 11 The same procedure as in Example 10 was carried out except that a polycarbonate film having a thickness of 200 μm was used. Example 12 The same procedure as in Example 10 was performed except that a polycarbonate film having a thickness of 300 μm was used. Example 13 The same procedure as in Example 10 was carried out except that a polycarbonate film having a thickness of 400 μm was used. Example 14 The same procedure as in Example 10 was carried out except that a polycarbonate film having a thickness of 500 μm was used.

Example 15 The same procedure as in Example 7 was carried out except that the hard coat material composition B was used instead of the hard coat material composition A. [Comparative Example 2] The same operation as in Example 10 was carried out except that a polycarbonate film having a thickness of 100 µm was used.

Example 16 The irradiation amount of ultraviolet rays was 1000 m
The same operation as in Example 11 was performed, except that J / cm ² was used. [Example 17] The same operation as in Example 16 was carried out except that a polycarbonate film having a thickness of 300 µm was used. Example 18 The same procedure as in Example 17 was carried out except that the coating amount of the hard coat material composition B was changed to change the thickness of the hard coat layer to 10 μm. Example 19 The same procedure as in Example 18 was performed except that a polycarbonate film having a thickness of 400 μm was used. Example 20 The same procedure as in Example 18 was carried out except that a polycarbonate film having a thickness of 500 μm was used.

Comparative Example 3 The same procedure as in Example 16 was carried out except that a polycarbonate film having a thickness of 150 μm was used. [Comparative Example 4] The same operation as in Example 18 was carried out except that a polycarbonate film having a thickness of 200 µm was used. [Comparative Example 5] The same operation as in Example 18 was performed except that the coating amount of the hard coat material composition B was changed and the thickness of the hard coat layer was changed to 15 µm.

Example 21 Example 21 was carried out in the same manner as in Example 19 except that the coating amount of the hard coat material composition B was changed and the thickness of the hard coat layer was changed to 15 μm. Example 22 The same procedure was performed as in Example 21 except that a polycarbonate film having a thickness of 500 μm was used.

Comparative Example 6 (Hard Coat Material Composition C) Photopolymerizable monomer: 15 parts of pentaerythritol tetraacrylate Photopolymerizable oligomer: 12 parts Polyester acrylate (having a molecular weight of about 1200 to 1500) Photopolymerization initiator: Irgacure 184 (manufactured by Ciba Geigy) 3 parts Toluene / isopropyl alcohol = 1/1 (weight ratio) 70 parts The above were mixed and dissolved to obtain an ultraviolet curable resin composition C. Example 17 was carried out in the same manner as in Example 17, except that the hard coat material composition C was used instead of the hard coat material composition B.

Comparative Example 7 The same procedure as in Comparative Example 2 was carried out except that the hard coat material composition C was used instead of the hard coat material composition B. [Comparative Example 8] The same operation as in Comparative Example 7 was carried out except that a polycarbonate film having a thickness of 150 µm was used. Comparative Example 9 The same operation was performed as in Comparative Example 7, except that a polycarbonate film having a thickness of 200 μm was used. [Comparative Example 10] The same operation was performed as in Comparative Example 7, except that a polycarbonate film having a thickness of 300 µm was used.

Example 23 The same procedure was performed as in Comparative Example 7, except that a polycarbonate film having a thickness of 400 μm was used. Example 24 The same operation as in Comparative Example 7 was performed except that a polycarbonate film having a thickness of 500 μm was used.

[Comparative Example 11] The irradiation amount of ultraviolet rays was 1000 m
The same operation as in Example 23 was performed, except that J / cm ² was used. [Comparative Example 12] The same operation was performed as in Comparative Example 11, except that a polycarbonate film having a thickness of 500 µm was used.
Table 1 shows the results of Examples 1 to 24 and Comparative Examples 1 to 11.

[0074]

[Table 1]

As shown in Table 1, no crack was observed in the hard coat layer after molding in each of Examples 1 to 24. On the other hand, in Comparative Examples 1 to 11, cracks occurred in the hard coat layer after molding.

Example 25 Using the polycarbonate film with a hard coat layer obtained in Example 1, injection molding was performed as follows. The obtained polycarbonate film with a hard coat layer was cut into 10 cm x 20 cm to obtain two films. Referring to FIG. 5, the two films were mounted on injection molds (7), (8) and (9) such that the hard coat layers (1b) and (1b) were on the upper and lower sides, respectively. The mold was clamped so that a cavity (10) was formed between the surfaces of the bases (1a) and (1a) of both films. Next, a molten polycarbonate resin temperature of 315 ° C. and a mold temperature of 80
Injection molding was performed at 30 ° C. for a molding time of 30 sec including the filling time of the molten polycarbonate resin and the cooling time to obtain a molded product substrate having a hard coat layer provided on both surfaces. Whether or not cracks were generated in the hard coat layer after molding was visually observed and observed using a magnifying glass with a magnification of 10 times. As a result, no crack was generated in the hard coat layer on both sides.

[0077]

According to the present invention, a plastic film having a hard coat layer free from cracks is provided. The plastic film with a hard coat layer has excellent scratch resistance, and is widely used as, for example, various industrial materials such as display covers of OA equipment, nameplates, food packaging containers, building materials, decorative materials, optical materials, and household materials. Can be.

When the plastic film with a hard coat layer is used for producing a plastic molded article having a hard coat layer provided by an injection molding method, cracks do not occur in the hard coat layer after molding. In particular, according to the present invention, there is provided a polycarbonate film with a hard coat layer for obtaining a polycarbonate molded article provided with a hard coat layer by an injection molding method. The plastic film with a hard coat layer of the present invention can be used when manufacturing various injection-molded articles, but the window of a car, the window of a train or an airplane, the show window, the sun terrace provided with the hard coat layer is provided with the hard coat layer. It is particularly suitable for producing transparent plates for automobiles, sunroofs for automobiles and the like.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the base film thickness x (μm) of a plastic film with a hard coat layer and the elongation y (%) of a plastic film with a hard coat layer in a tensile test.

FIG. 2 is a cross-sectional view of the transparent plastic film with a hard coat layer of the present invention.

FIG. 3 is a view for explaining the use of the transparent plastic film with a hard coat layer of the present invention, and is a cross-sectional view showing a state in which an injection molding die is clamped.

4 is a cross-sectional view showing a layer structure of a molded article provided with a hard coat layer obtained by injection molding in FIG.

FIG. 5 is a view for explaining the use of the transparent plastic film with a hard coat layer of the present invention, and is a cross-sectional view showing a state in which an injection molding die is clamped.

6 is a cross-sectional view showing a layer structure of a molded article obtained by injection molding of FIG. 5 and having a hard coat layer provided on both sides.

[Explanation of symbols]

 (1): Transparent plastic film with hard coat layer (1a): Plastic base film (1b): Hard coat layer (2): Molded product body (3) (4) (7) (8) (9): Mold (5) (10): Cavity

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) // B29L 9:00 B29L 9:00 C08L 69:00 C08L 69:00

Claims (8)

[Claims] 1. A transparent plastic film having a hard coat layer on one side of a plastic base film, wherein the thickness of the base film is represented by x (μm), and the plastic film having the hard coat layer is fixed at 22 ° C. on one side. The elongation percentage when pulled under the condition of a pulling speed of 20 mm / min is represented by y (%). When x ≦ 100, y <5.7 When 100 ≦ x ≦ 150, y <−0.018x +
7.5 When 150 ≦ x ≦ 200, y <−0.008x +
6.0 When 200 ≦ x ≦ 300, y <−0.005x +
5.4 When 300 ≦ x ≦ 400, y <−0.003x +
4.8 When 400 ≦ x ≦ 500, y <−0.002x +
4.4 A transparent plastic film having a hard coat layer in which no crack is generated in the hard coat layer when a tensile test is performed under the above conditions in a region satisfying the relationship y <3.4 when 500 ≦ x. 2. The transparent plastic film having a hard coat layer according to claim 1, wherein the plastic base film is a polycarbonate film. 3. The transparent plastic film having a hard coat layer according to claim 1, which is wound in a roll. 4. The plastic base film according to claim 1, wherein said plastic base film has a thickness of 100 μm to 500 μm.
4. A transparent plastic film having the hard coat layer according to any one of 3. 5. When producing a plastic molded product by injection molding, a transparent plastic film having a hard coat layer on one side of a plastic base film is produced by:
The hard coat layer is set so that it faces one mold surface in the injection mold, and the mold is clamped so that a cavity is formed between the base surface and the other mold surface of the film, Injecting the molten resin into the cavity, cooling and molding the molded article body, and laminating and integrating the plastic film on the surface of the molded article body to obtain a molded article provided with a hard coat layer A transparent plastic film having a hard coat layer according to any one of claims 1 to 4, which is used for: 6. In producing a plastic plate-like molded product by injection molding, two transparent plastic films each having a hard coat layer on one surface of a plastic base film, each having a hard coat layer formed on one side of an injection mold. Set to face the mold surface and the other mold surface, mold clamping so that a cavity is formed between the base surfaces of the two films, and then inject the molten resin into the cavity, Cooling and molding the molded article body, the plastic film is laminated and integrated on both sides of the molded article body, and used to obtain a plate-shaped molded article having a hard coat layer provided on both sides. 5. A transparent plastic film having the hard coat layer according to any one of 4. 7. A plastic molded article in which the transparent plastic film having the hard coat layer according to claim 1 is laminated and integrated, and the hard coat layer is provided on the surface. 8. A display cover, nameplate or packaging container comprising the transparent plastic film having the hard coat layer according to claim 1. Description: