JP2012210756A - Laminate hard coat film for molding, method for manufacturing the same, and method for manufacturing resin molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate hard coat film for molding, which has superior molding characteristics, scratch resistance, and adhesion.SOLUTION: The laminate hard coat film 1 for molding compises a hard coat layer 12 containing the active energy ray curable resin and a protective film 13, sequentially on a base material film 11. The hard coat layer 12 contains the hindered phenol antioxidant by the range of 1-10 pts.wts for 100 pts.wts. of the active energy ray curable resin. In the laminate hard coat film 1 for molding, after heat-treatment of ≥150°C, the elongation under the atmosphere of 23°C and 50%RH is ≥30%.

Description

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

  Resin-molded products are often used for portable information terminal devices such as mobile phones, notebook personal computers, household electrical appliances, automobile interior and exterior parts, and the like. These resin molded products are usually decorated by printing or the like on the surface in order to improve the design properties after molding the plastic resin. Conventionally, as a method for decorating a resin molded product, for example, a colored paint is applied to the surface of a three-dimensional resin molded product by injection molding or the like, or screen printing is performed. Furthermore, in order to protect the surface of the product, a method of applying a clear hard coat by spraying or dipping a hard coat material has been performed. However, it is difficult for such a conventional decoration method to perform decoration with a high design property, and it is difficult to apply to the work environment by chemical substances such as volatile solvents contained in paints used in spray coating. Due to concerns about influence, in-mold molding provided on the surface of a resin molded product using a decorative film provided with a pattern or a hard coat layer by printing or coating a film has become widespread as an alternative method.

  In-mold transfer, which is one of in-mold molding methods (hereinafter referred to as “IMD method” in the present specification), is a hard coat layer, a design layer, or an adhesive layer on one side of a base film. This is a technique in which a decorative film on which a transfer foil is laminated is held in an injection mold, and the transfer foil is transferred to the surface of a resin molding simultaneously with the injection molding. In the case of this IMD method, the base film which is the support for the hard coat layer and the design layer of the decorative film is finally peeled off as a product and does not remain on the surface of the resin molding.

  In-mold lamination (hereinafter, abbreviated as “IML method” in the present specification), which is another method of in-mold molding, includes a hard coat layer on one side of a base film. In this technique, a decorative film having a pattern layer, an adhesive layer or the like formed on the other surface is held inside an injection mold, and the decorative film is adhered to the surface of the resin molding simultaneously with the injection molding. There is film insert molding as a similar method to the IML method, and after the decorative film is heated (preliminary heating), a preformed product of the decorative film is obtained by a mold and then held in the injection mold as the next step. In this method, a decorative film molding and a resin molding preliminarily molded by injection molding are bonded and integrated. The IML method is characterized in that the decorative film is integrated with a resin molded product, and a deep-drawn decorative molded product can be manufactured as compared with the IMD method.

  In addition to the in-mold molding method, there is a vacuum molding method as a molding method using a decorative film. In this vacuum molding method, the decorative film is heated (pre-heated) under vacuum, and then brought into contact with a resin molded product prepared in advance. It is the method of pasting together. In this vacuum forming method, only a weak air pressure works rather than a mechanical strong force sandwiched between molds such as in-mold molding. Therefore, to make the decorative film follow the surface shape of the molded product, from the softening temperature of the film It is necessary to perform preheating at a sufficiently high temperature. If the preheating temperature is too low, when the decorative film is pasted to a resin molded product having a deep-drawn three-dimensional shape, the film will not be stretched sufficiently. In the bent part, even if a decorative film is pasted, it does not become a sharp bend but becomes a shallow rounded shape, which impairs the original shape of the resin molded product. In addition, it is necessary to select an appropriate preheating temperature depending on the resin composition type of the base film of the decorative film, and when using a biaxially stretched polyester film, it is harder than the base film of polycarbonate or acrylic resin, In particular, high-temperature preheating (about 150 to 200 ° C.) is required.

  Various configurations have been conventionally proposed as a decorative film used in the molding method using the decorative film as described above (for example, Patent Documents 1 to 3).

JP 2003-430034 A JP 2007-256485 A JP 2009-148438 A

The decorative film used in the molding method described above mainly requires the following characteristics.
First, moldability is required. That is, it is important that the film has sufficient extensibility to follow three-dimensional molding and that the hard coat layer does not crack even if it is stretched. In particular, when used in the IML method or vacuum forming method capable of deep drawing, the moldability is required to be particularly good. In particular, in the case of vacuum molding, when high-temperature preheating is performed at the time of molding, even if it has good extensibility before heating, thermosetting of the hard coat layer proceeds due to preheating, and the extensibility is high. There is a problem that deteriorates greatly.

  Second, surface hardness (pencil hardness, scratch resistance) is required. In the case of the above IML method or vacuum molding method, the decorative film needs to be integrated with the resin molded product, the hard coat layer is disposed on the outermost surface, and the surface protection function of the resin molded product must be provided. For this purpose, a high surface hardness is required, but generally the hardness and extensibility of the hard coat layer are in a trade-off relationship, and it has been a conventional problem to satisfy both characteristics.

Third, adhesion between the base film and the hard coat layer is required. If the adhesion is poor, defects such as film peeling occur at the time of molding.
In addition to the above, winding processability is required. Since the decorative film is stored in a wound state after its production, the decorative film is required to have a holding power (cohesive force) that can be wound and stored without breaking the hard coat layer.
However, according to the study of the present inventors, it has been found that any of the conventional decorative films proposed in the above-mentioned patent documents has a problem that the above-mentioned characteristics cannot be obtained in a well-balanced manner.

  Therefore, an object of the present invention is to provide a laminated hard coat film for molding having good moldability, scratch resistance, and adhesion, a method for producing the same, and a method for producing a resin molded product using the laminated hard coat film. Is to provide. In particular, an object is to provide a laminated hard coat film for molding suitable for use in a vacuum molding method in which high-temperature preheating is performed during molding, and a method for producing the same.

  As a result of intensive studies to achieve the above-mentioned problems, the inventors of the present invention are a laminated hard coat film for molding comprising a hard coat layer containing an active energy ray-curable resin on a substrate film, The hard coat layer contains a hindered phenolic antioxidant in a range of 1 to 10 parts by weight with respect to 100 parts by weight of the active energy ray-curable resin, and the laminated hard coat film has a temperature of 150 ° C. After the above heat treatment, the inventors have found that the above problem can be solved by having an elongation rate of 30% or more in an atmosphere of 23 ° C. and 50% RH (the invention of claim 1).

  Here, the base film is an easily formed biaxially stretched polyethylene terephthalate film having a stress at elongation (100% elongation stress = F100) in the range of 50 MPa <F100 <135 MPa at room temperature (23 ° C.). (Invention of claim 2) is preferable.

  Moreover, the laminated hard coat film for molding of the present invention has a configuration in which a protective film is provided on the side of the hard coat layer opposite to the base film, and the protective film is peelable from the hard coat layer. (Invention of claim 3) is preferable.

  The present invention also provides a preferred method for producing the above laminated hard coat film for molding. That is, on one surface of the substrate film, a coating composition containing at least an active energy ray-curable resin, a polymerization initiator and a hindered phenol antioxidant is applied and dried to form a hard coat layer. If necessary, the hard coat layer is irradiated with an active energy ray, and then a protective film is laminated on the side of the hard coat layer opposite to the base film. (Invention of claim 4).

  Further, the laminated hard coat film for molding obtained by the production method of the present invention has an elongation of 30% or more in an atmosphere of 23 ° C. and 50% RH after heat treatment at 150 ° C. or more (claims). 5 invention).

  The present invention also provides a method for producing a resin molded product using the above-described laminated hard coat film for molding. That is, the molding laminated hard coat film according to any one of claims 1 to 3 or the molding laminated hard coat film obtained by the method for producing a molding laminated hard coat film according to claim 4 or 5 is used. A method for producing a resin molded product, wherein a decorative layer by printing or the like is formed on the laminated hard coat film as necessary, and then an adhesive layer is formed thereon, and then the laminated hard coat film is heated to 150 ° C. or higher. Next, the laminated hard coat film is integrated with the resin molded body by molding, and thereafter, the laminated hard coat film integrated with the resin molded body is post-exposed with active energy rays. This is a method for producing a resin molded product (Invention of claim 6).

According to the present invention, it is possible to provide a laminated hard coat film for molding that has good moldability, scratch resistance, and adhesion.
Moreover, according to this invention, the suitable manufacturing method of the said lamination | stacking hard coat film for a shaping | molding can be provided.
According to the present invention, it is possible to provide a laminated hard coat film for molding suitable for use in a vacuum molding method in which high temperature preheating is performed particularly during molding and a method for producing the same.

  Further, according to the present invention, by using the laminated hard coat film, it is possible to produce a resin molded product having, for example, gloss and depth and high design properties.

It is sectional drawing of the layer structure which shows one Embodiment of the lamination | stacking hard-coat film for shaping | molding of this invention. It is sectional drawing which shows the layer structure of the lamination | stacking hard-coat film for shaping | molding which provided the decorating layer.

Hereinafter, embodiments of the present invention will be described in detail.
[Laminated hard coat film for molding]
First, the laminated hard coat film for molding of the present invention will be described.
FIG. 1 is a cross-sectional view of a layer configuration showing an embodiment of a laminated hard coat film for molding according to the present invention.
In the laminated hard coat film 1 for molding of the present invention shown in FIG. 1, a hard coat layer 12 is provided on a base film 11, and a protective film 13 is provided on the hard coat layer 12. ing.

  Although it does not specifically limit as said base film 11 which can be used for this invention, It is a material which can be thermoformed, Comprising: It is a material which can be extended with a weak force with a low stress at the time of expansion | extension. In the present invention, for example, a polyethylene terephthalate (PET) film, an acrylic film, a polycarbonate (PC) film and the like can be preferably used. In the case of the polyethylene terephthalate film, a general-purpose biaxially stretched PET film may be used, but in order to obtain better moldability, it is particularly preferable to use an easily molded biaxially stretched PET film. This easily-molded biaxially stretched PET film has a low heat softening temperature, can be stretched with a weak force, and is a relatively inexpensive material. The elongation stress (100% elongation stress = F100) of the easily-molded biaxially stretched PET film is in the range of 50 MPa <F100 <135 MPa at room temperature. If the F100 value is greater than 135 MPa, even when preheated at high temperature, the elongation at the time of molding becomes insufficient, and the surface shape of the resin molded product cannot be followed. Due to the stress, a “return” occurs in which the entire laminated film for molding bonded to the resin molded product is warped. On the other hand, if the F100 value is less than 50 MPa, the film becomes soft and soft, and the pencil hardness of the hard coat layer is reduced, and handling during molding is hindered.

The acrylic film and the polycarbonate (PC) film are both unstretched films and can be suitably used for any molding method.
Although there is no restriction | limiting in particular also about the thickness of the base film 11, For example, about 25 micrometers-150 micrometers are used. For example, a thin one having a thickness of about 50 μm or less is preferably used for the IMD method, and a thick one having a thickness of about 100 μm or more is preferably used for the vacuum forming method or the IML method.

  In the present invention, the resin contained in the hard coat layer 12 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 has hardness (pencil hardness, scratch resistance). It is possible to adjust the degree of cross-linking depending on the amount of exposure of the active energy ray and the active energy ray-curable resin, in which both the extensibility and hardness of the hard coat layer 12 can be adjusted. It can be preferably used.

  The active energy ray-curable resin used in the present invention is not particularly limited as long as it is a transparent resin that is cured by irradiation with active energy rays (for example, ultraviolet rays, electron beams, etc.). For example, urethane acrylate It can be appropriately selected from a resin based on polyester, a polyester acrylate based resin and the like. Preferred examples of the active energy ray-curable resin include those composed of an ultraviolet curable polyfunctional acrylate having two or more (meth) acryloyl groups in the molecule. Specific examples of the UV curable polyfunctional acrylate having two or more (meth) acryloyl groups in the molecule include neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and trimethylol. Polyol polyacrylates such as propane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, bisphenol A diglycidyl Epoxys such as diacrylate of ether, diacrylate of neopentyl glycol diglycidyl ether, di (meth) acrylate of 1,6-hexanediol diglycidyl ether ( A) Polyester (meth) acrylate, polyhydric alcohol, polyisocyanate and hydroxyl group-containing (meta) which can be obtained by esterifying acrylate, polyhydric alcohol and polyhydric carboxylic acid and / or anhydride and acrylic acid ) Urethane (meth) acrylate obtained by reacting acrylate, polysiloxane poly (meth) acrylate, and the like.

  The ultraviolet curable polyfunctional acrylates may be used alone or in combination of two or more, and the content thereof is preferably 50 to 95% by weight based on the resin solid content of the hard coat layer coating material. In addition to the polyfunctional (meth) acrylate, preferably 10% by weight or less of 2-hydroxy (meth) acrylate and 2-hydroxypropyl (meth) acrylate with respect to the resin solid content of the hard coat layer coating material. Monofunctional acrylates such as glycidyl (meth) acrylate can also be added.

  Moreover, as resin contained in the said hard-coat layer 12, in addition to the said active energy ray curable resin, thermoplastic resins, such as polyethylene, a polypropylene, a polystyrene, a polycarbonate, polyester, a phenol resin, a urea resin, unsaturated You may contain thermosetting resins, such as polyester, an epoxy, and a silicon resin, in the range which does not impair the extensibility and hardness of the hard-coat layer 12. FIG.

  The hard coat layer 12 needs to have a holding power (cohesive force) that can wind up the laminated hard coat film 1 for molding of the present invention. For that purpose, it is preferable that the resin contained in the hard coat layer 12 is not sticky and has a touch feeling preferably in the range of room temperature to about 40 ° C. (corresponding to a winding storage temperature). In addition, in the structure which provides the protective film 13 on the hard-coat layer 12 like FIG. 1, the holding force of the grade which can be wound up as mentioned above is required at the minimum, but this holding force is impaired. If not, it may be sticky.

  In the present invention, the hard coat layer 12 contains a heat-resistant stabilizer (antioxidant) for suppressing thermal curing due to preheating during molding. In particular, when high-temperature preheating (about 150 to 200 ° C.) is performed at the time of molding in the vacuum molding method, even if the film has good extensibility before heating, the hard coating layer is hardened by preheating and stretched. There is a risk that the performance will deteriorate significantly.

In the present invention, it is preferable to use a hindered phenolic antioxidant as the heat-resistant stabilizer. The hindered phenol-based antioxidant is preferably contained in the range of 1 to 10 parts by weight with respect to 100 parts by weight of the active energy ray curable resin. If the content is less than 1 part by weight, the above-described effect of suppressing thermosetting may not be sufficiently obtained. Further, when the content is more than 10 parts by weight, there is no problem in terms of suppressing thermal curing, but according to the study of the present inventors, curing inhibition occurs due to the heat stabilizer, and post-exposure is performed after resin molding. However, the hard coat layer is not sufficiently cured, scratch resistance (hardness) cannot be obtained, and there is a problem in the adhesion of the laminated film. As described above, a hindered phenol-based antioxidant is preferably used as the heat-resistant stabilizer because it maintains the curability and adhesion of the hard coat layer and has a good balance with the effect of suppressing thermosetting. .
In addition to the hindered phenol-based antioxidant, for example, a hindered amine-based light stabilizer (such as HALS), a benzotriazole-based UV absorber, an antifoaming agent, a leveling agent, etc. You may use together. Known and publicly available photopolymerization initiators can be used as long as the ultraviolet curable resin can be sufficiently cured by ultraviolet rays, such as acetophenones and benzophenones.

In addition, as other additives to be added to the hard coat layer 12, a surface tension adjuster, antifouling agent, and nanoparticles such as silica and alumina for preventing scratches on the surface, as long as the effects of the present invention are not impaired. You may contain a dispersion, an antistatic agent, etc. as needed.

  The coating thickness of the hard coat layer 12 of the present invention is not particularly limited, but is preferably in the range of, for example, about 3 to 30 μm. If the thickness is less than 3 μm, it will be difficult to obtain the required hardness. Moreover, when the thickness is thicker than 30 μm, it becomes difficult to obtain good extensibility.

  The protective film 13 is provided on the opposite side of the hard coat layer 12 from the base film 11 and can be peeled off from the hard coat layer 12. By providing this protective film 13, it is possible to stably store the sheet-like laminated laminated hard coat film 1 according to the present invention in a wound state. Moreover, since the protective film 13 is finally peeled off at any stage of the resin molded product manufacturing process, there is no transfer of the adhesive to the hard coat layer 12 (no adhesive remains). Thus, it is preferable to have a structure that can be peeled off.

  Further, when the laminated hard coat film 1 on which the protective film 13 is laminated is subjected to a molding process of a resin molding, the protective film 13 has an extensibility that can follow the elongation of the hard coat layer 12 during molding. Preferably it is. The protective film 13 has, for example, ultraviolet transparency so that it can cope with an exposure step (details will be described later) in the production of the laminated hard coat film 1 and a post-exposure step (details will be described later) in the production of a resin molded product. It is suitable to have.

  The surface shape of the protective film 13 on the side in contact with the hard coat layer 12 may be transferred to the surface of the hard coat layer 12 when the protective film 13 is peeled off. For example, it is possible to make the surface of the hard coat layer 12 matte (matte) by forming an uneven shape on the surface of the protective film 13 and transferring the uneven shape to the surface of the hard coat layer 12. is there. Further, by smoothing the surface of the protective film 13, glossiness is produced on the surface of the hard coat layer.

  The protective film 13 that can be used in the present invention is not particularly limited as long as it is a material having the above-mentioned characteristics. For example, a polyethylene terephthalate (PET) film, a polyolefin film (for example, polyethylene, polypropylene, etc.) is preferable. Can be used. In the case of the polyethylene terephthalate film, a general-purpose biaxially stretched PET film may be used, but in terms of extensibility, it is particularly preferable to use an easily molded biaxially stretched PET film.

Further, instead of using the PET film or the like as the protective film 13, the protective film 13 may be formed by applying a water-based resin paint such as polyvinyl alcohol (PVA) on the hard coat layer 12. As the coating material for such a protective film, a coating material that does not dissolve the hard coat layer that is the base during coating is preferable, and the dilution solvent for the coating material is more preferably an alcohol or water system.
The thickness of the protective film 13 is preferably about 10 μm to 50 μm because it requires a surface protection function and a minimum film strength that does not break when peeled off. In addition, it can be peeled off appropriately before and after molding and post-exposure, but it can prevent process scratches such as printing and vapor deposition, and deposits and contamination such as dust on the hard coat layer during molding or until product shipment is completed. And it can also be set as the state affixed until the resin molding provided with the laminated film for shaping | molding is used as a final product. If the hard coat layer is peeled off after being cured by post-exposure, the hard coat layer may stick to the hard coat layer, and it is easy to peel off without excessive adhesion to the hard coat layer. It is necessary that the components do not transfer to the hard coat layer.
The material for the adhesive layer is not particularly limited, and examples thereof include general-purpose materials such as acrylic, urethane, polyester, rubber, and silicone pressure-sensitive adhesives.

The laminated hard coat film 1 having the above-described configuration according to the present invention has an elongation rate of 30% or more in an atmosphere of 23 ° C. and 50% RH after heat treatment at 150 ° C. or more. As a result, especially in the case of a resin molding method such as vacuum molding, even if preheating at a high temperature (150 ° C. or higher) is performed during molding, the hard coat layer is inhibited from thermosetting and good moldability (elongation) is maintained. can do.
Note that the layer configuration shown in FIG. 1 is an embodiment of the present invention and is not limited thereto. For example, a urethane resin or the like for enhancing adhesion between the hard coat layer 12 and the base film 11 is used. It can be applied to provide an anchor layer, or the base film can be easily adhered by corona treatment or plasma treatment. Further, an antireflection layer can be provided on the hard coat layer 12.

[Method for producing laminated hard coat film for molding]
Next, the manufacturing method of the laminated hard coat film for molding according to the present invention will be described.
This invention also provides about the suitable manufacturing method of the said lamination | stacking hard coat film 1 for a shaping | molding.
That is, a hard coat layer 12 is formed by applying and drying a coating composition containing at least an active energy ray-curable resin, a polymerization initiator, and a hindered phenol antioxidant on one surface of the base film 11. (Step 1), if necessary, the hard coat layer 12 is irradiated with active energy rays (Step 2), and then the protective film 13 on the side of the hard coat layer 12 opposite to the substrate film 11 is applied. Is a method for producing a laminated hard coat film for molding, characterized by laminating (step 3).

  In the step 1, an active energy ray-curable resin, a polymerization initiator, a hindered phenol antioxidant, and other additives are dissolved and dispersed in an appropriate solvent, and a coating is applied on the base film 11. The hard coat layer 12 is formed by drying. The solvent can be appropriately selected according to the solubility of the resin and may be any solvent that can uniformly dissolve or disperse at least solids (resin, polymerization initiator, antioxidant, and other additives). Examples of such a solvent include ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), ethers (dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons (hexane, etc.), alicyclic hydrocarbons ( Cyclohexane, etc.), aromatic hydrocarbons (toluene, xylene, etc.), halogenated carbons (dichloromethane, dichloroethane, etc.), esters (methyl acetate, ethyl acetate, butyl acetate, etc.), alcohols (methanol, ethanol, isopropanol, Butanol, cyclohexanol, etc.), cellosolves (methyl cellosolve, ethyl cellosolve, etc.), cellosolve acetates, sulfoxides, amides and the like. Further, the solvents may be used alone or in combination.

  The coating method is not particularly limited, but can be applied by a method that allows easy adjustment of the coating thickness, such as gravure coating, microgravure coating, fountain bar coating, slide die coating, slot die coating, etc. It is. The film thickness of the hard coat layer 12 can be measured by observing a film cross-sectional photograph with a microscope or the like and actually measuring from the coating film interface to the surface.

In the above step 2, as necessary, the applied hard coat layer 12 is irradiated with an active energy ray with a small exposure amount of, for example, 50 mJ / cm ² or less. As a result, the crosslinking of the active energy ray-curable resin contained in the hard coat layer 12 proceeds to some extent, so-called semi-cured state. When the solvent in the coating film volatilizes, for example, by hot air drying after the coating of the hard coat layer 12, or when the heat-crosslinking proceeds to some extent, the holding power of the hard coat layer 12 is obtained to some extent, Although step 2 does not necessarily need to be performed, it is advantageous to perform step 2 above in order to adjust both the stretchability and retention properties of the coated hard coat layer 12 in a well-balanced manner.

As the active energy rays to be irradiated, ultraviolet rays, electron beams or the like are used depending on the type of resin. Examples of the ultraviolet light source include a high-pressure mercury lamp, a metal halide lamp, and an electrodeless lamp.
When the exposure amount (integration) exceeds 50 mJ / cm ^2, for example, the crosslinking degree of the active energy ray-curable resin contained in the hard coat layer 12 becomes too high, and the stretchability of the coated hard coat layer 12 is increased. May deteriorate.

  In the step 3, the protective film 13 is laminated on the surface of the hard coat layer 12, that is, on the side opposite to the base film 11. As described above, for example, a protective film 13 is formed by bonding a PET film or the like to the surface of the hard coat layer 12 or by applying an aqueous resin such as polyvinyl alcohol (PVA) on the hard coat layer 12. May be.

  The sheet-like laminated hard coat film 1 manufactured as described above is wound and stored. The laminated hard coat film 1 obtained by the present invention has both good extensibility (elongation rate) and winding processability (holding force) before use (before molding).

[Method of manufacturing resin molded product]
Next, a method for producing a resin molded product according to the present invention will be described.
The present invention also provides a method for producing a resin molded product using the above-described laminated hard coat film for molding.
That is, after a decorative layer by printing or the like is formed on the laminated hard coat film 1 as necessary (step A), and then an adhesive layer is formed thereon, a preliminary of 150 ° C. or more is formed on the laminated hard coat film 1. Heat is applied (step B), and then the laminated hard coat film 1 is integrated with a resin molded body by molding (step C), and then the laminated hard coat film 1 integrated with the resin molded body is applied. A method for producing a resin molded product, characterized in that post-exposure with active energy rays is performed (step D).

In the step A, a decorative layer (design layer) is formed by printing, vapor deposition, or the like to give the necessary design properties to the surface of the base film 11 of the laminated hard coat film 1. FIG. 2 shows the layer structure of the laminated film (that is, the decorative film 2) on which the decorative layer 14 is formed.
As the printing method, known printing methods such as gravure printing, offset printing, screen printing, flexographic printing, and ink jet can be used.

  In the step B, after forming an adhesive layer thereon, the laminated hard coat film 1 or a decorative film 2 on which a decorative layer is formed (for convenience of explanation, the decorative film 2 and the decorative film 2 are hereinafter referred to as “laminated hard The film is described as “Coat Film 1”.) Is preheated for the purpose of softening before molding. The preheating temperature is basically determined by the type of film used. For example, a PET film requires preheating at a higher temperature than other types of films. The easily molded PET film has a lower heat softening temperature than the general-purpose PET film. Further, the necessary preheating temperature varies depending on the molding method, and a particularly high heating temperature is required in the vacuum molding method. When an easy mold PET film requires an elongation rate of 30% or more by vacuum forming, and more particularly 100 to 300% or more, particularly moldability is required, it is difficult to mold unless the temperature is about 180 to 200 ° C. In the present invention, as described above, by adding a heat-resistant stabilizer (antioxidant) to the hard coat layer 12, thermal curing by high-temperature preheating at the time of molding proceeds and the film extensibility deteriorates. Can be suppressed. Therefore, the laminated hard coat film of the present invention can be particularly suitably used for a molding method that requires preheating at a high temperature during molding.

In the step C, the laminated hard coat film 1 is integrated with a resin molded body by molding. For example, in the vacuum molding method, the preheated laminated hard coat film 1 is brought into contact with a previously produced resin molded product, and the film is stretched and bonded to the surface of the resin molded product to be integrated.
As a typical vacuum forming machine, for example, a commercially available double-sided vacuum forming machine (manufactured by Fuse Vacuum Co., Ltd.) can be used. The basic principle is that it has two vacuum chambers that are divided up and down by a laminated sheet for molding, and a lifting platform that can be moved up and down is installed in the lower vacuum chamber. Set to The upper and lower vacuum chambers are evacuated, and the laminated sheet for molding is preheated by an infrared lamp heater from above. Next, pressurizing the upper vacuum chamber (or returning it to atmospheric pressure) creates a differential pressure above and below the film, and the molded laminated film is stretched while following the surface irregularities of the resin molded product, and the molded product is passed through the adhesive layer. Close contact with the surface. Thereafter, the integrated molded product is taken out from the molding machine.

In the step D, post-exposure by active energy ray irradiation is performed on the laminated hard coat film 1 integrated with the resin molded body. Thereafter, the hard coat layer 12 is completely cured by exposure. The active energy ray source can use the same thing as the manufacturing process (process 2) of the above-mentioned laminated hard coat film 1. The exposure amount of the post-exposure is an exposure amount necessary for completely curing the hard coat layer 12 and may be set as appropriate.
The resin molded product that has been subjected to the post-exposure is completed by appropriately performing a finishing process such as trimming.

  As described above, according to the present invention, it is possible to exhibit good moldability (extensibility) of the laminated hard coat film before molding. And even if it performs high temperature preheating at the time of shaping | molding, thermosetting can be suppressed and favorable moldability can be maintained also at the time of shaping | molding. Moreover, since photocuring inhibition by a heat-resistant stabilizer does not occur, sufficient scratch resistance (hardness) can be ensured by post-exposure after molding, and the adhesiveness of the laminated film is also good. That is, according to the present invention, it is possible to provide a laminated hard coat film for molding that is excellent in moldability, scratch resistance, and adhesion, and that these characteristics can be obtained in a well-balanced manner.

The following examples illustrate the invention, but are not intended to limit the invention.
The coating thickness was measured by observing the cross section with a scanning electron microscope. Unless otherwise specified, “parts” and “%” described below represent “parts by weight” and “% by weight”, respectively.

[Example 1]
<Preparation of paint>
Polymer type acrylate UV curable resin “Unidic RC29-117 (trade name)” (solid content 50%, manufactured by DIC Corporation) 100 parts, Irgacure 184 (photopolymerization initiator, Ciba Specialty Chemicals Co., Ltd.) 5 parts), 2 parts of hindered phenolic antioxidant (heat stabilizer) “IRGANOX1010 (trade name)” (manufactured by Ciba Specialty Chemicals), and TINUVIN1130 (trade name) benzotriazole UV absorber ) 2 parts (made by Ciba Specialty Chemical Co., Ltd.) and 0.3 parts of leveling agent F-177 (fluorine leveling agent, made by DIC Corporation) with butyl acetate in the solid content of UV curable resin paint The paint was prepared by diluting until the concentration reached 35% and stirring sufficiently.
<Preparation of laminated hard coat film>
The above-mentioned paint was applied to one surface of a 125 μm-thick biaxially stretchable PET film “Soft Shine X1130 (trade name)” (stress at elongation F100 = 87 MPa, manufactured by Toyobo Co., Ltd.) with a bar coater. Dry with hot air at 3 ° C. for 3 minutes. The thickness of the obtained coating film was 7 μm. Next, using a laminator, a polyolefin film having a thickness of 50 μm (trade name: Hitalex ML-2020, manufactured by Hitachi Chemical Co., Ltd.) was bonded to the surface of the coating film to produce a laminated hard coat film.

[Example 2]
<Preparation of paint>
A coating material similar to that of Example 1 was prepared except that the amount of the heat-resistant stabilizer added was 10 parts.
<Preparation of laminated hard coat film>
A laminated hard coat film was produced in the same manner as in Example 1 using the paint.

[Example 3]
<Preparation of paint>
A coating material similar to that of Example 1 was prepared except that the amount of the heat-resistant stabilizer added was 10 parts.
<Preparation of laminated hard coat film>
A laminated hard coat film was produced in the same manner as in Example 1 except that the heat treatment temperature after coating was 220 ° C.

[Example 4]
<Preparation of paint>
A coating material similar to that of Example 1 was prepared except that the amount of the heat-resistant stabilizer added was 10 parts.
<Preparation of laminated hard coat film>
A laminated hard coat film was prepared in the same manner as in Example 1 except that the heat treatment temperature after coating was 160 ° C.

[Example 5]
<Preparation of paint>
The heat resistance stabilizer was changed to the hindered phenol antioxidant “IRGANOX1098 (trade name)” (manufactured by Ciba Specialty Chemicals), and the addition amount was 2 parts, as in Example 1. The paint was adjusted.
<Preparation of laminated hard coat film>
A laminated hard coat film was produced in the same manner as in Example 1 using the paint.

[Example 6]
<Preparation of paint>
The heat resistance stabilizer was changed to the hindered phenol antioxidant “IRGANOX1098 (trade name)” (manufactured by Ciba Specialty Chemicals), and the addition amount was 10 parts, as in Example 1. The paint was adjusted.
<Preparation of laminated hard coat film>
A laminated hard coat film was produced in the same manner as in Example 1 using the paint.

[Example 7]
<Preparation of paint>
Example 1 except that the UV curable resin was changed to a urethane acrylate UV curable resin “Folceed No. 370C (trade name)” (solid content 40%, manufactured by China Paint Co., Ltd.). The paint was adjusted.
<Preparation of laminated hard coat film>
A laminated hard coat film was produced in the same manner as in Example 1 using the paint.

[Example 8]
<Preparation of paint>
The UV curable resin was changed to a urethane acrylate UV curable resin “Folceed No. 370C (trade name)” (solid content 40%, manufactured by China Paint Co., Ltd.), and the above heat stabilizer (Example) The coating material was adjusted in the same manner as in Example 1 except that the amount of addition of “the same as 1” was 10 parts.
<Preparation of laminated hard coat film>
A laminated hard coat film was produced in the same manner as in Example 1 using the paint.

[Example 9]
<Preparation of laminated hard coat film>
The same as Example 1 except that “Soft Shine X1130” was a 125 μm-thick biaxially stretchable easily-formed PET film “Soft Shine TA009 (trade name)” (stress at elongation F100 = 131 MPa, manufactured by Toyobo Co., Ltd.) Using the paint, a laminated hard coat film was produced in the same manner.

[Example 10]
<Preparation of laminated hard coat film>
The same paint as in Example 1 except that “Soft Shine X1130” is a 125 μm-thick biaxially stretched PET film “Cosmo Shine A4300 (trade name)” (elongation stress F100 = 153 MPa, manufactured by Toyobo Co., Ltd.) A laminated hard coat film was produced in the same manner.

[Comparative Example 1]
<Preparation of paint>
A coating material similar to that of Example 1 was prepared except that the heat stabilizer was not added.
<Preparation of laminated hard coat film>
A laminated hard coat film was produced in the same manner as in Example 1 using the paint.

[Comparative Example 2]
<Preparation of paint>
A coating material was prepared in the same manner as in Example 1 except that the addition amount of the heat stabilizer was 15 parts.
<Preparation of laminated hard coat film>
A laminated hard coat film was produced in the same manner as in Example 1 using the paint.

[Comparative Example 3]
<Preparation of paint>
Change the above UV curable resin to urethane acrylate UV curable resin “Forse Seed No. 370C (trade name)” (solid content 40%, manufactured by China Paint Co., Ltd.) and add the above heat stabilizer. A coating material was prepared in the same manner as in Example 1 except that it was not.
<Preparation of laminated hard coat film>
A laminated hard coat film was prepared in the same manner as in Example 1 except that the heat treatment temperature after coating was 180 ° C.

The laminated hard coat films of Examples and Comparative Examples produced as described above were evaluated for the following items, and the results are summarized in Table 1 below.
(1) Elongation rate It conformed to the tensile test of JIS K 7127. After the heat treatment, the sample was allowed to stand and measured in an atmosphere of 23 ° C. and 50% RH. The protective film was peeled off, and a test piece having a width of 15 mm and a length of 150 mm was pulled at a pulling speed of 50 mm / min and a distance between chucks of 100 mm, and the tensile elongation until cracks occurred in the hard coat layer on the surface was measured.

Each laminated hard coat film was irradiated with ultraviolet rays having an exposure amount of 500 mJ / cm ² to cure the hard coat layer, and then scratch resistance and adhesion were measured.
(2) Scratch resistance After peeling off the protective film, Steel Wool # 0000 was reciprocated 10 times while applying a load of 100 g / cm ² , and the degree of occurrence of scratches was evaluated visually. “◯” indicates that the scratches are not noticeable even when visually observed, “△” indicates that there are some scratches but there is no practical problem, and “X” indicates that the scratch is conspicuous and has a practical problem.

(3) Adhesiveness The adhesiveness between the hard coat layer and the substrate film was evaluated in accordance with the cross-cut test of JIS K 5600-5-6. After peeling off the protective film of each laminated hard coat film, forming a 100 square grid with a cutter, pressing the adhesive tape from above and peeling it off five times, then the remaining area ratio of the hard coat layer It was measured. A case where the remaining area ratio was 95% or more was indicated as “◯”, and a case where the remaining area ratio was less than 95% was indicated as “X”.

As is clear from the results in Table 1 above, in all of Examples 1 to 8 of the present invention, thermosetting can be suppressed even when subjected to high-temperature heat treatment (equivalent to preheating at the time of molding), and good Has excellent moldability (elongation rate). Moreover, there is no inhibition of photocuring by the heat stabilizer, and both scratch resistance and adhesion are good. That is, it is possible to obtain a laminated hard coat film in which the properties of moldability, scratch resistance, and adhesion are exhibited in a well-balanced manner.
On the other hand, in Comparative Examples 1 and 3 to which no heat stabilizer was added, although the adhesion and scratch resistance were good, thermal curing due to high-temperature heat treatment could not be suppressed, and the film elongation was Is small, and good moldability cannot be obtained. Further, in Comparative Example 2 in which the amount of heat stabilizer added is large, although the elongation percentage of the film is large, photocuring inhibition by the heat stabilizer occurs, and the scratch resistance and adhesion are poor.

DESCRIPTION OF SYMBOLS 1 Molding laminated hard coat film 2 Decorative film 11 Base film 12 Hard coat layer 13 Protective film 14 Decorative layer

Claims (6)

A laminated hard coat film for molding formed by providing a hard coat layer containing an active energy ray-curable resin on a base film,
The hard coat layer contains a hindered phenolic antioxidant in a range of 1 to 10 parts by weight with respect to 100 parts by weight of the active energy ray-curable resin,
A laminated hard coat film for molding, wherein the laminated hard coat film has an elongation rate of 30% or more in an atmosphere of 23 ° C. and 50% RH after heat treatment at 150 ° C. or more.   The base film is an easily molded biaxially stretched polyethylene terephthalate film having an elongation stress (100% elongation stress = F100) in the range of 50 MPa <F100 <135 MPa at room temperature (23 ° C.). The laminated hard coat film for molding according to claim 1.   The lamination for molding according to claim 1 or 2, wherein a protective film is provided on a side of the hard coat layer opposite to the base film, and the protective film is peelable from the hard coat layer. Hard coat film.   On one side of the base film, a coating composition containing at least an active energy ray-curable resin, a polymerization initiator and a hindered phenolic antioxidant is applied and dried to form a hard coat layer. Accordingly, the hard coat layer is irradiated with active energy rays, and then a protective film is laminated on the side of the hard coat layer opposite to the substrate film, thereby producing a laminated hard coat film for molding Method.   The obtained laminated hard coat film for molding has an elongation of 30% or more in an atmosphere of 23 ° C and 50% RH after heat treatment at 150 ° C or more. For producing a laminated hard coat film. Resin molding using the laminated hard coat film for molding according to any one of claims 1 to 3, or the laminated hard coat film for molding obtained by the method for producing a laminated hard coat film for molding according to claim 4 or 5. A method for manufacturing a product,
After forming a decorative layer by printing or the like on the laminated hard coat film as necessary, and then forming an adhesive layer thereon, the laminated hard coat film is preheated to 150 ° C. or higher, and then the laminated hard coat film Manufacturing a resin molded product characterized in that a coat film is integrated with a resin molded body by molding, and thereafter, the laminated hard coat film integrated with the resin molded body is subjected to post-exposure with active energy rays. Method.

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