Resin sheet, resin molded article, vehicle, vehicle component, method for producing resin molded article, and method for producing vehicle and vehicle component

Abstract

To provide a resin sheet having good adhesiveness when combining a hardly adhesive resin such as a polypropylene resin at the same time of injection molding, a resin molded article provided with a resin molding integrated with the resin sheet, a vehicle and a vehicle component having the resin molded article, a method for producing the resin molded article, and a method for producing the vehicle and the vehicle component.SOLUTION: A resin sheet 1A includes: a support film 10; and a curable resin layer 20 consisting of a curable resin composition provided on the support film, wherein the support film 10 contains at least one resin selected from the group consisting of an acid-modified propylene resin and a chlorinated polyolefin resin, or the resin sheet further includes a primer layer provided on the curable resin layer side of the support film, and the primer layer contains at least one resin selected from the group consisting of an acid-modified polypropylene resin and a chlorinated polyolefin resin.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a resin sheet, a resin molded product, a vehicle, vehicle parts, a method for manufacturing a resin molded product, and a method for manufacturing a vehicle and vehicle parts.

Background Art

[0002] Conventionally, as methods for decorating simultaneously with injection molding, there are, for example, an insert molding method and an in-mold molding method. In the insert molding method, a decorated sheet preformed into a three-dimensional shape by a vacuum molding die is inserted into an injection molding die, and molten resin is injected into the die to integrate the molded decorated sheet and the resin. In the in-mold molding method, a decorated sheet is inserted into an injection molding die, the decorated sheet is molded in the die, and molten resin is injected into the die to integrate the molded decorated sheet and the resin. As a decorated sheet used for such a decorating method, for example, the decorated sheet described in Patent Document 1 is known as the prior art. The decorated sheet described in Patent Document 1 includes a support sheet containing an ABS resin and a surface layer provided on the support sheet.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the decorated sheet described in Patent Document 1, when the injection molding resin is a polypropylene-based resin which is a difficult-to-adhere resin, there may occur a problem that the adhesion between the decorated sheet and the injection molding resin becomes insufficient.

[0005] Therefore, an object of the present invention is to provide a resin sheet having good adhesiveness with a difficult-to-adhere resin such as a polypropylene-based resin when integrated with the difficult-to-adhere resin such as a polypropylene-based resin simultaneously with injection molding, a resin molded product including the resin sheet integrated therewith, a vehicle and vehicle parts having the resin molded product, a method for manufacturing the resin molded product, and a method for manufacturing the vehicle and the vehicle parts.

Means for Solving the Problems

[0006] As a result of intensive studies, the present inventor has found that the above problems can be solved by incorporating a predetermined resin into the support film or forming a primer layer containing a predetermined resin on the support film, and has completed the present invention. The gist of the present invention is as follows. [1] A resin sheet comprising a support film and a curable resin layer made of a curable resin composition provided on the support film, wherein the support film contains at least one resin selected from the group consisting of an acid-modified polypropylene-based resin and a chlorinated polyolefin-based resin, or the resin sheet further comprises a primer layer provided on the support film on the curable resin layer side, and the primer layer contains at least one resin selected from the group consisting of an acid-modified polypropylene-based resin and a chlorinated polyolefin-based resin. [2] The resin sheet according to [1] above, wherein the acid-modified polypropylene-based resin is a copolymer of propylene or propylene and ethylene and at least one unsaturated carboxylic acid selected from the group consisting of maleic anhydride, itaconic acid, fumaric acid, oleic acid, acrylic acid, and methacrylic acid. [3] The resin sheet according to [1] or [2] above, wherein the chlorinated polyolefin-based resin is at least one resin selected from the group consisting of chlorinated polypropylene, chlorinated ethylene-propylene copolymer, chlorinated propylene-butene copolymer, and chlorinated ethylene-propylene-butene copolymer. [4] The resin sheet according to any one of [1] to [3] above, wherein the ratio of the thickness of the support film to the thickness of the resin sheet is 30% or more. [5] The resin sheet according to any one of [1] to [4] above, wherein the curable resin composition is a thermosetting resin composition. [6] A resin molded product comprising the resin sheet according to any one of [1] to [5] above and a resin molded body integrated with the resin sheet. [7] A vehicle having the resin molded product according to [6] above. [8] A vehicle part having the resin molded product according to [6] above. [9] A method for manufacturing a resin molded product, comprising inserting the resin sheet according to any one of [1] to [5] above into an injection mold, clamping the injection mold, injecting a resin in a fluid state into a cavity formed by clamping the injection mold, and integrating the resin sheet and the injected resin on the support film side with respect to the curable resin layer.

[10] A step of heating and softening the resin sheet according to any one of [1] to [5] above, and then vacuum molding the resin sheet using a vacuum mold to produce a molded body of the resin sheet, and A method for manufacturing a resin molded product, comprising inserting the molded body into an injection mold, clamping the injection mold, injecting a resin in a fluid state into a cavity formed by clamping the injection mold, and integrating the molded body and the injected resin on the support film side with respect to the curable resin layer.

[11] The curable resin composition of the resin sheet is a thermosetting resin composition, The method for manufacturing a resin molded product according to

[10] above, wherein the resin sheet is thermally cured in the vacuum mold, or the resin sheet is thermally cured by the resin injected in the injection mold, or the resin sheet is thermally cured by both of these.

[12] A step of heating and softening the resin sheet according to any one of [1] to [5] above, a step of pre-molding by vacuum suctioning the softened resin sheet and bringing it into close contact with the molding surface of an injection mold, and A method for manufacturing a resin molded product, including a step of injecting a resin in a fluid state into a cavity formed by clamping the injection mold, and integrating the resin sheet preformed on the support film side with respect to the curable resin layer and the injected resin.

[13] The curable resin composition of the resin sheet is a thermosetting resin composition, The method for manufacturing a resin molded product according to

[12] above, wherein the resin sheet is thermally cured when it is adhered along the molding surface of the injection mold, or the resin sheet is thermally cured by the resin injected in the injection mold, or the resin sheet is thermally cured by both of these.

[14] A method for manufacturing a vehicle having a resin molded product, A method for manufacturing a vehicle, including a step of manufacturing the resin molded product by the method for manufacturing a resin molded product according to any one of [9] to

[13] above.

[15] A method for manufacturing a vehicle part having a resin molded product, A method for manufacturing a vehicle part, including a step of manufacturing the resin molded product by the method for manufacturing a resin molded product according to any one of [9] to

[13] above. [Effect of the Invention]

[0007] According to the present invention, when integrated with a difficult-to-adhere resin such as a polypropylene-based resin simultaneously with injection molding, a resin sheet having good adhesiveness with a difficult-to-adhere resin such as a polypropylene-based resin, a resin molded body integrated with the resin sheet, a resin molded product including the resin molded body, a vehicle and a vehicle part having the resin molded product, a method for manufacturing the resin molded product, and a method for manufacturing the vehicle and the vehicle part can be provided. [Brief Description of the Drawings]

[0008]

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Mode for Carrying Out the Invention

[0009] [Resin Sheet] (First Embodiment) Hereinafter, with reference to the drawings, a resin sheet according to a first embodiment of the present invention will be described. As shown in FIG. 1, a resin sheet 1A according to a first embodiment of the present invention includes a support film 10 containing at least one resin selected from the group consisting of an acid-modified polypropylene-based resin and a chlorinated polyolefin-based resin, and a curable resin layer 20 made of a curable resin composition provided on the support film.

[0010] <Support Film> The support film 10 contains at least one resin selected from the group consisting of an acid-modified polypropylene-based resin and a chlorinated polyolefin-based resin. Thereby, when the resin sheet 1A is integrated with a poorly adherent resin such as a polypropylene-based resin simultaneously with injection molding, the adhesiveness of the resin sheet 1A to the poorly adherent resin becomes good.

[0011] <Acid-Modified Polypropylene-Based Resin> The acid-modified polypropylene-based resin contained in the support film 10 is not particularly limited. Examples of the acid-modified polypropylene-based resin include those obtained by subjecting raw material polypropylene to a graft reaction with at least one of α,β-unsaturated carboxylic acid and its acid anhydride, and those obtained by copolymerizing raw material polypropylene with at least one of α,β-unsaturated carboxylic acid and its acid anhydride. Among these, those obtained by subjecting raw material polypropylene to a graft reaction with at least one of α,β-unsaturated carboxylic acid and its acid anhydride are preferable.

[0012] As the raw material polypropylene, for example, homopolypropylene and propylene-α-olefin copolymer can be used, and homopolypropylene is preferred. The propylene-α-olefin copolymer is obtained by copolymerizing α-olefin with propylene as the main component. Examples of the α-olefin include ethylene, 1-butene, 1-heptene, 1-octene, 4-methyl-1-pentene, vinyl acetate, and the like. These α-olefins can be used alone or in combination of two or more. Among these α-olefins, ethylene and 1-butene are preferred, and ethylene is more preferred.

[0013] The acid-modified propylene-based resin preferably contains 60 mol% or more of propylene, more preferably 70 mol% or more, still more preferably 80 mol% or more, and even more preferably 90 mol% or more. The higher the propylene content, the better the adhesion to the difficult-to-adhere resin such as the polypropylene resin of the resin sheet 1A. The upper limit of the range of the propylene content in the acid-modified propylene-based resin is not particularly limited, but is, for example, 99 mol%.

[0014] Examples of at least one of the α,β-unsaturated carboxylic acid and its acid anhydride include maleic acid, itaconic acid, fumaric acid, oleic acid, acrylic acid, methacrylic acid, and their acid anhydrides. Among these, maleic anhydride, itaconic acid, fumaric acid, oleic acid, acrylic acid, and methacrylic acid are preferred, and maleic anhydride is more preferred.

[0015] The production method of the acid-modified propylene-based resin is not particularly limited, and examples thereof include radical graft reaction (that is, a reaction in which radical species are generated for the polymer serving as the main chain, and unsaturated carboxylic acid and acid anhydride are graft-polymerized using the radical species as the polymerization initiation point).

[0016] Although the radical generator is not particularly limited, it is preferable to use an organic peroxide. Examples of the organic peroxide include, but are not limited to, peroxides such as di-tert-butyl peroxyphthalate, tert-butyl hydroperoxide, dicumyl peroxide, benzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxypivalate, methyl ethyl ketone peroxide, di-tert-butyl peroxide, lauroyl peroxide; azonitriles such as azobisisobutyronitrile and azobisisopropylnitrile.

[0017] The acid value of the acid-modified propylene-based resin is preferably 2 to 50 mgKOH / g, more preferably 3 to 40 mgKOH / g, and still more preferably 5 to 30 mgKOH / g. When the acid value is 2 mgKOH / g or more, the adhesive strength is exhibited well. On the other hand, when the acid value is 50 mgKOH / g or less, the compatibility tends to be good. The acid value of the acid-modified propylene-based resin can be measured in accordance with JIS K0070-1992.

[0018] The melting point of the acid-modified propylene-based resin is preferably 50°C or higher and 100°C or lower, more preferably 55°C or higher and 90°C or lower, and still more preferably 60°C or higher and 87°C or lower. When it is 50°C or higher, the cohesive force derived from crystallization becomes strong and the adhesiveness is good. On the other hand, when it is below the above value, the solution stability and fluidity are good and the operability during adhesion is excellent.

[0019] The weight average molecular weight of the acid-modified polypropylene-based resin is preferably 10,000 to 200,000, more preferably 20,000 to 180,000, still more preferably 30,000 to 160,000, and even more preferably in the range of 40,000 to 140,000. The weight average molecular weight is a value determined from a standard polystyrene calibration curve by gel permeation chromatography (GPC) method.

[0020] <Chlorinated polyolefin resin> The chlorinated polyolefin resin contained in the resin sheet 1A is obtained by chlorinating a polyolefin resin. Examples of the chlorination method include a method of introducing chlorine atoms into a polyolefin resin by blowing chlorine gas into the polyolefin resin.

[0021] Examples of the polyolefin resins used for producing the chlorinated polyolefin resin include propylene resins such as polypropylene, ethylene-propylene copolymer, propylene-butene copolymer, and ethylene-propylene-butene copolymer. These polyolefin resins can be used alone or in combination of two or more. As the polyolefin resin, those using a Ziegler-Natta catalyst or a metallocene catalyst as a polymerization catalyst are preferable. As the polyolefin resin, polypropylene and propylene-based random copolymers using a metallocene catalyst as a polymerization catalyst are more preferable, and polypropylene, ethylene-propylene copolymer, propylene-butene copolymer, or ethylene-propylene-butene copolymer using a metallocene catalyst as a polymerization catalyst is even more preferable.

[0022] The blowing of chlorine gas can be carried out under ultraviolet irradiation and can be carried out both in the presence and absence of a radical reaction initiator. The pressure when blowing chlorine gas is not limited and may be normal pressure or under pressure. The temperature when blowing chlorine gas is not particularly limited, but is usually 50 to 140 °C. As the radical reaction initiator, organic peroxide-based compounds or azonitriles such as 2,2-azobisisobutyronitrile can be used.

[0023] Examples of the organic peroxide compound include di-t-butyl peroxide, dicumyl peroxide, t-butyl cumyl peroxide, benzoyl peroxide, dilauryl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, 1,4-bis[(t-butylperoxy)isopropyl]benzene, 1,1-bis(t-butylperoxy)-3,5,5-trimethylcyclohexane, 1,1-bis(t-butylperoxy)-cyclohexane, cyclohexanone peroxide, t-butyl peroxybenzoate, t-butyl peroxyisobutyrate, t-butyl peroxy-3,5,5-trimethylhexanoate, t-butyl peroxy-2-ethylhexanoate, t-butyl peroxyisopropyl carbonate, and cumyl peroxy octoate. Among them, di-t-butyl peroxide, dicumyl peroxide, and dilauryl peroxide are preferred. The radical generator may be a single radical generator or a combination of a plurality of radical generators.

[0024] The chlorine content of the chlorinated polyolefin resin is preferably 1 to 45% by mass, more preferably 10 to 45% by mass, and even more preferably 18 to 45% by weight. The chlorine content of the chlorinated polyolefin resin can be measured based on JIS-K7229.

[0025] The chlorine content varies depending on factors such as the type of polyolefin resin, reaction scale, and reaction apparatus. Therefore, the adjustment of the chlorine content can be performed while monitoring the blowing amount and time of chlorine.

[0026] The weight average molecular weight of the chlorinated polyolefin resin is preferably 5,000 to 100,000, more preferably 7,000 to 60,000, and even more preferably 8,000 to 40,000. The weight average molecular weight is a value obtained from a standard polystyrene calibration curve by gel permeation chromatography (GPC) method.

[0027] The content of at least one resin selected from the group consisting of an acid-modified polypropylene resin and a chlorinated polyolefin resin in the support film 10 is preferably 1 part by mass or more with respect to 100 parts by mass of the resin component. When the content of the above resin is 1 part by mass or more, when integrated with a difficult-to-adhere resin such as a polypropylene resin simultaneously with injection molding, the adhesiveness of the resin sheet 1A to the difficult-to-adhere resin such as a polypropylene resin can be further improved. From such a viewpoint, the content of the above resin is more preferably 3 parts by mass or more, and still more preferably 5 parts by mass or more with respect to 100 parts by mass of the resin component. The upper limit value of the content range of the above resin is not particularly limited, and is, for example, 100 parts by mass. That is, the resin component in the support film 10 may be only at least one resin selected from the group consisting of an acid-modified polypropylene resin and a chlorinated polyolefin resin. However, from the viewpoints of heat resistance, mechanical strength, etc. of the support film, the content of the above resin is preferably 80 parts by mass or less, more preferably 75 parts by mass or less, and still more preferably 50 parts by mass or less with respect to 100 parts by mass of the resin component.

[0028] The support film 10 may contain resins other than the acid-modified polypropylene resin and the chlorinated polyolefin resin. In that case, the acid-modified polypropylene resin and the chlorinated polyolefin resin are preferably used by mixing with these other resins, and the support film 10 may be composed of a resin composition containing the acid-modified polypropylene resin and the chlorinated polyolefin resin and these other resins. From the viewpoint of adhesiveness to a difficult-to-adhere resin such as a polypropylene resin, the support film 10 preferably contains a polyolefin resin as a resin other than the acid-modified polypropylene resin and the chlorinated polyolefin resin, and more preferably contains a polypropylene resin among them. By using a polypropylene resin, the acid-modified polypropylene resin and the chlorinated polyolefin resin can be appropriately mixed into the support film. In addition, the heat resistance of the resin sheet is improved, and it can also be suitably used for injection molding using an injection resin as a polypropylene resin.

[0029] Examples of polyolefin resins other than polypropylene resins used for the support film include polyethylene resins such as low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), and linear low-density polyethylene (LLDPE). The polypropylene resin used for the support film is not particularly limited, and examples thereof include propylene homopolymers (homopolypropylene) and copolymers of propylene and other olefins. The copolymer of propylene and other olefins may be any of a block copolymer, a random copolymer, and a random block copolymer, but a random copolymer (random polypropylene) is preferred. In the copolymer of propylene and other olefins, examples of the propylene-α-olefin containing propylene, for example, preferably 75% by mass or more, more preferably 90% by mass or more, may be mentioned. Examples of other olefins copolymerized with propylene include α-olefins such as ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-nonene, and 1-decene, and among these, ethylene is preferred. Therefore, an ethylene-propylene random copolymer is more preferred. The content of the polypropylene resin other than the acid-modified polypropylene resin and the chlorinated polyolefin resin in the support film 10 is, for example, 0 parts by mass or more and 99 parts by mass or less, preferably 70 parts by mass or more and 99 parts by mass or less, more preferably 80 parts by mass or more and 97 parts by mass or less, and still more preferably 75 parts by mass or more and 95 parts by mass or less with respect to 100 parts by mass of the resin component.

[0030] The ratio of the thickness of the support film 10 to the thickness of the resin sheet 1A is preferably 30% or more. When the ratio of the thickness of the support film 10 to the thickness of the resin sheet 1A is 30% or more, it is possible to suppress the deterioration of the curable resin layer 20 due to the pressure and heat of the injected resin during injection molding. Also, the handleability of the resin sheet 1A is improved. From such a viewpoint, the ratio of the thickness of the support film 10 to the thickness of the resin sheet 1A is more preferably 50% or more, still more preferably 80% or more, and even more preferably 90% or more. From the viewpoint of ensuring the thickness of the curable resin layer 20, the ratio of the thickness of the support film 10 to the thickness of the resin sheet 1A is preferably 99% or less, and more preferably 98% or less.

[0031] The thickness of the support film 10 is not particularly limited as long as it satisfies the range of the ratio of the thickness of the support film 10 to the thickness of the resin sheet 1A described above, but is preferably 0.05 mm or more and 5 mm or less. When the thickness of the support film 10 is 0.05 mm or more, it is possible to further suppress the deterioration of the curable resin layer 20 due to the pressure and heat of the injected resin during injection molding. When the thickness of the support film 10 is 5 mm or less, the molding of the resin sheet 1A becomes easier. From such a viewpoint, the thickness of the support film 10 is more preferably 0.1 mm or more and 4 mm or less, and still more preferably 0.2 mm or more and 3 mm or less.

[0032] <Curable Resin Layer> The curable resin layer 20 in the resin sheet 1A is composed of the curable resin composition as described above. The curable resin layer 20 may have any curability such as thermosetting, moisture curing, or photocuring, but preferably has thermosetting properties. Therefore, the curable resin composition is preferably a thermosetting resin composition. By having thermosetting properties, the curable resin layer 20 can easily cure the resin sheet 1A by heating. Note that the curable resin layer may be in an uncured state or a semi-cured state that does not completely cure in the resin sheet before being used in the production of the resin molded product described later.

[0033] The curable resin composition contains a curable resin, and the curable resin is preferably a thermosetting resin. The curable resin preferably has a functional group, and the functional group is preferably a functional group that reacts with a reactive group (for example, an isocyanate group) possessed by at least one compound of a blocked isocyanate and a melamine-based compound described later. Specific examples of the functional group include a hydroxyl group, a carboxyl group, and an amino group, and among these, a hydroxyl group is preferable. The curable resin may have only one type of functional group or may have two or more types of functional groups. Further, two or more functional groups may be contained in one molecule.

[0034] The content of the curable resin in the curable resin composition is not particularly limited, but based on the total amount of the curable resin composition, it is preferably 40% by mass or more and 95% by mass or less, more preferably 50% by mass or more and 90% by mass or less, and still more preferably 55% by mass or more and 85% by mass or less.

[0035] Examples of the curable resin include (meth)acrylic resins, polycarbonate resins, polyester resins, epoxy resins, etc., and among these, (meth)acrylic resins are preferable. These are preferably thermosetting resins.

[0036] Examples of the (meth)acrylic resin used in the curable resin composition include (meth)acrylic resins having a plurality of functional groups. The functional group is as described above, and the (meth)acrylic resin preferably has a hydroxyl group. The (meth)acrylic resin may have only one type of functional group or may have two or more types of functional groups. Therefore, the (meth)acrylic resin preferably contains a (meth)acrylic polyol having a plurality of hydroxyl groups, and more preferably contains an acrylic polyol.

[0037] (Meta)acrylic resin is an acrylic polymer obtained preferably by polymerizing a monomer mixture containing a (meta)acrylic acid ester monomer and a functional group-containing monomer having the above functional groups such as a hydroxyl group, an amino group, and a carboxyl group. The monomer mixture may also contain components other than the (meta)acrylic acid ester monomer and the functional group-containing monomer such as a styrene derivative monomer. Note that "(meta)acrylic" means methacrylic or acrylic, and the same applies to other similar terms.

[0038] Examples of the (meta)acrylic acid ester monomer include (meta)acrylic acid ester monomers having no such functional groups as mentioned above, such as alkyl (meta)acrylates with an alkyl group having about 1 to 18 carbon atoms, (meta)acrylates having an aromatic ring such as benzyl (meta)acrylate and phenoxydiethylene glycol (meta)acrylate, and 2-ethoxyethyl (meta)acrylate. Examples of the functional group-containing monomer include (meta)acrylic acid ester monomers having a hydroxyl group such as 2-hydroxyethyl (meta)acrylate, (meta)acrylic acid ester monomers having an amino group such as 2-aminoethyl (meta)acrylate, and monomers having a carboxyl group such as (meta)acrylic acid. As the (meta)acrylic resin, a copolymer obtained by block or graft polymerization of the above acrylic polymer and another monomer or polymer may also be used.

[0039] The content of the (meta)acrylic polyol in the curable resin composition is not particularly limited, but based on the total amount of the curable resin composition, it is preferably 40% by mass or more and 90% by mass or less, more preferably 50% by mass or more and 85% by mass or less, and still more preferably 55% by mass or more and 80% by mass or less. By setting the (meta)acrylic resin within the above range, it is easy to improve the coatability, curability, etc. of the curable resin layer 20.

[0040] The curable resin composition preferably contains, as the above (meth)acrylic resin, a (meth)acrylic resin having a weight average molecular weight (Mw) of 50,000 or more and 1,000,000 or less, being solid, and having a plurality of functional groups (hereinafter also referred to as a high molecular weight (meth)acrylic resin). By including a (meth)acrylic resin having a weight average molecular weight within the above range, it becomes easier to maintain the curable resin layer 20 in a certain shape even before curing. Also, it becomes easier to impart tackiness and stretchability etc. to the curable resin layer 20. The curable resin layer 20 has tackiness and stretchability, so that it has good shape followability during molding and is less likely to cause color unevenness etc. Further, when the weight average molecular weight is within the above range, it becomes easier to increase the hardness of the curable resin layer after curing. The above weight average molecular weight is preferably 100,000 or more and 500,000 or less, more preferably 120,000 or more and 400,000 or less. In the present specification, the weight average molecular weight (Mw) is measured by gel permeation chromatography (GPC) and is determined as a standard polystyrene conversion value. Also, being solid means being solid at normal temperature (23°C) and normal pressure (1 atm).

[0041] The above high molecular weight (meth)acrylic resin is preferably a (meth)acrylic polyol having a plurality of hydroxyl groups. As described above, the (meth)acrylic polyol can be obtained, for example, by polymerizing a monomer mixture containing a (meth)acrylate monomer and a hydroxyl group-containing monomer. In the curable resin composition, the (meth)acrylic resin may be used alone or in combination of two or more.

[0042] The curable resin composition may contain, as the curable resin, in addition to the above high molecular weight (meth)acrylic resin, a resin having a weight average molecular weight of less than 50,000 (hereinafter also referred to as a plasticized resin). The curable resin composition contains a plasticizing resin with a low weight-average molecular weight in addition to a high-molecular-weight (meth)acrylic resin, which makes it easy to balance and improve coating properties, curability, tackiness, stretchability, etc. Also, the wettability with respect to the support film 10 can be improved, and the adhesive strength to the support film 10 can be increased.

[0043] As the plasticizing resin, those which are compatible with the high-molecular-weight (meth)acrylic resin and have a heat-curable functional group are preferred. That is, the plasticizing resin preferably constitutes a curable resin, particularly a thermosetting resin. Examples of the resin used for the plasticizing resin include (meth)acrylic resins, polycarbonate resins, polyester resins, and epoxy resins, and among them, (meth)acrylic resins or polycarbonate resins are preferred.

[0044] Examples of the (meth)acrylic resin used as the plasticizing resin include oligomers having functional groups such as hydroxyl groups, amino groups, and carboxyl groups. The (meth)acrylic resin used as the plasticizing resin is, for example, as described above for the (meth)acrylic resin, and preferably a (meth)acrylic polyol having a plurality of hydroxyl groups is used. Also, a poly(meth)acrylate having a carboxyl group is also preferred. Further, as the polycarbonate resin used as the plasticizing resin, polycarbonate polyol is preferred.

[0045] The weight-average molecular weight of the plasticizing resin is preferably 300 or more and 30,000 or less, more preferably 400 or more and 20,000 or less. Also, it is desirable that the plasticizing resin is liquid at normal temperature and normal pressure.

[0046] As the plasticizing resin, at least one of (meth)acrylic polyol or polycarbonate polyol having a plurality of hydroxyl groups is preferred.

[0047] The content of the plasticized resin in the curable resin composition is, based on the content of the high molecular weight (meth)acrylic resin, in terms of mass ratio, for example, 0 or more and 0.9 or less, preferably 0.01 or more and 0.5 or less, more preferably 0.03 or more and 0.1 or less.

[0048] The curable resin composition preferably contains a curing agent for the curable resin, and specifically, it is preferable to contain at least one compound selected from blocked isocyanates and melamine-based compounds (hereinafter also referred to as compound (X)).

[0049] Among the above, as compound (X), blocked isocyanate is preferable. Blocked isocyanate is a compound in which the isocyanate group is blocked by a protecting group. When exposed to high temperature, the protecting group (blocking agent) undergoes thermal dissociation and detaches, and a curing reaction occurs between the generated isocyanate group and the functional group (typically, the hydroxyl group of polyol) in the above-mentioned curable resin. Blocked isocyanate can be obtained, for example, by reacting a blocking agent with an isocyanate compound having two or more isocyanate groups in one molecule.

[0050] The isocyanate compound having two or more isocyanate groups in one molecule is not particularly limited, and examples include tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, or modified products thereof. Examples of the blocking agent include pyrazole, phenols, oximes, lactams, malonic esters, etc. Among these, pyrazole is preferable. The content of blocked isocyanate in the curable resin composition is preferably adjusted so that the number of functional groups in the curable resin is 0.4 or more and 1.8 or less, more preferably 0.6 or more and 1.5 or less, relative to the number of isocyanate groups in the blocked isocyanate.

[0051] A melamine-based compound is a compound having a melamine skeleton in the compound, and a compound that causes a dehydration condensation reaction may be used. For example, alkylolated melamine derivatives such as monomethylol melamine and hexamethylol melamine obtained by reacting melamine with formaldehyde under an alkali, compounds partially etherified by reacting an alcohol with an alkylolated melamine derivative, and mixtures thereof can be mentioned. The melamine-based compound may be either a monomer or a multimer of dimer or higher, or a mixture thereof may be used.

[0052] The curable resin composition preferably contains a (meth)acrylic resin and a blocked isocyanate. By containing a (meth)acrylic resin and a blocked isocyanate, the curable resin layer 20 is likely to have desired flexibility, and it is easy to improve the adhesion and adhesive strength to the support film 10. Further, after curing by heat curing, it is easy to achieve high hardness, and the scratch resistance of the coating after curing is also good.

[0053] The content of the compound (X) in the curable resin composition is preferably 5% by mass or more, more preferably 10% by mass or more, and still more preferably 15% by mass or more based on the total amount of the curable resin composition. When the content of the compound (X) is equal to or higher than the above lower limit value, the curable resin composition can be sufficiently cured, and it is easy to obtain a curable resin layer 20 having excellent strength. Further, from the viewpoint of enabling the curable resin composition to contain a thermosetting resin, a colorant, etc. to be described later at a certain ratio, the content of the compound (X) is preferably 50% by mass or less, more preferably 45% by mass or less, and still more preferably 40% by mass or less based on the total amount of the curable resin composition. In addition, although the curable resin composition may be diluted with a volatile component such as a solvent as described later, in this specification, the content (% by mass) of each component in the curable resin composition means a value based on the solid content excluding the volatile component.

[0054] In addition to the curable resin and the curing agent, the curable resin composition may appropriately contain components according to the performance required for the curable resin layer 20. For example, a colorant such as a pigment, a dye, or a brightening agent may be contained to make the curable resin layer 20 a colored layer. Further, a heat shielding material may be contained in the curable resin composition to make the curable resin layer 20 a heat shielding layer. Furthermore, the curable resin layer 20 may be composed of a clear layer described later. Among these, it is preferable that the curable resin composition contains at least a colorant.

[0055] Examples of the pigment used as the colorant include metal oxide pigments such as titanium oxide and iron oxide, inorganic pigments such as carbon black, clay, kaolin, barium sulfate, barium carbonate, calcium carbonate, talc, silica, and alumina white, and organic pigments such as azo pigments, quinacridone pigments, diketopyrrolopyrrole pigments, perylene pigments, perinone pigments, benzimidazolone pigments, vat pigments, isoindoline pigments, isoindolinone pigments, metal chelate azo pigments, phthalocyanine pigments, indanthrone pigments, dioxane pigments, and indigo pigments. However, the colorant is not limited to these. As the dye, known dyes can be used, and examples thereof include azo dyes, anthraquinone dyes, indigoid dyes, and stilbene dyes. The brightening agent is a compound that can impart brightness to the curable resin layer 20 and a compound that can impart a property of showing gloss when observed from multiple directions. The brightening agent is not particularly limited, and examples thereof include compounds having a titanium oxide layer provided on the surface of natural mica, synthetic mica, alumina flakes, glass flakes, etc.

[0056] The curable resin layer 20 more preferably contains at least one of a pigment or a brightening agent as the colorant, and further preferably contains a pigment. Also, it is preferable that the curable resin layer 20 contains both a pigment and a brightening agent.

[0057] The content of the colorant in the curable resin composition is not particularly limited, but is, for example, about 0.1 to 25% by mass, preferably 0.3 to 20% by mass, more preferably 0.5 to 12% by mass.

[0058] In addition to the above-mentioned additives such as colorants and heat shielding materials, the curable resin composition may also appropriately contain additives such as inorganic fillers other than pigments and brightening materials, curing catalysts, curing accelerators, surface conditioners, defoaming agents, crosslinking agents, dispersants, anti-aging agents, antioxidants, antistatic agents, antifungal agents, and rust preventives. In addition to the coloring layer and the heat shielding layer, various functions may be imparted to the curable resin layer. For example, by providing surface irregularities, surface properties such as matte or embossed finishes can be imparted. In addition, functions such as rust prevention, antifungal, heat insulation, and antistatic can also be achieved by incorporating components suitable for the purpose into the curable resin composition.

[0059] The curable resin layer 20 is composed of a single layer. However, the curable resin layer may be composed of two resin layers, or the curable resin layer may be composed of three or more resin layers. When the curable resin layer has a multilayer structure, various functions can be imparted to the curable resin layer.

[0060] In the case of a multilayer structure, each layer of the curable resin layer is preferably composed of the above-mentioned curable resin composition. Further, each layer may contain a colorant as described above to form a coloring layer, may contain a heat shielding material to form a heat shielding layer, or may be a clear layer without substantially containing a colorant.

[0061] In the case of a multilayer structure, the curable resin layer preferably has at least a coloring layer and a clear layer. When having a coloring layer and a clear layer, the coloring layer and the clear layer are preferably arranged in this order from the support film side. With such a layer configuration, when the resin sheet is integrated with the injection-molded resin, the coloring layer and the clear layer are arranged in this order from the injection-molded resin side. The curable resin layer can be colored by having a colored layer. Further, by providing a clear layer in addition to the colored layer, the colored layer can be protected or gloss can be imparted to the colored layer. The colored layer preferably contains a pigment as a colorant. Therefore, it is particularly preferable that the curable resin layer includes a clear layer and a colored layer.

[0062] Both the colored layer and the clear layer are preferably made of the above-described curable resin composition. The curable resin composition for the colored layer may contain a colorant as described above. When using a (meth)acrylic resin as the curable resin for the colored layer, it may contain at least a high molecular weight (meth)acrylic resin, but it is preferably to contain both a high molecular weight (meth)acrylic resin and a plasticizing resin. On the other hand, the clear layer is a transparent layer and may have transparency such that the color of the colored layer can be visually recognized from the outside through the clear layer. For example, the transmittance of light with a wavelength of 450 nm is preferably 80% or more. The clear layer is preferably a coating film that does not contain a colorant, but may contain a small amount of a colorant as long as its function is not impaired. When using a (meth)acrylic resin as the curable resin for the clear layer, it may contain at least a high molecular weight (meth)acrylic resin, and in that case, it may or may not contain a plasticizing resin.

[0063] Of course, when the curable resin layer has a multilayer structure, it is not limited to the two-layer structure of the clear layer and the colored layer, and can have various laminated structures. It is also possible to provide two or more colored layers and one or more clear layers to form a structure of three or more layers, or it may consist of two colored layers with the clear layer omitted. Also, two or more clear layers may be provided. Further, a heat insulating layer or the like may be provided between the clear layer and the colored layer to form a structure of three or more layers.

[0064] The thickness of the curable resin layer 20 is not particularly limited, but is, for example, 20 μm or more and 200 μm or less, preferably 30 μm or more and 100 μm or less. In addition, when a colored layer and a clear layer are provided in the curable resin layer, the thickness of the colored layer is not particularly limited, but is, for example, 10 μm or more and 100 μm or less, preferably 15 μm or more and 50 μm or less. Also, the thickness of the clear layer is not particularly limited, but is, for example, 10 μm or more and 100 μm or less, preferably 15 μm or more and 50 μm or less.

[0065] <Release layer> As shown in FIG. 2, the resin sheet 1B may include a release layer 30 on the side opposite to the support film 10 side of the curable resin layer 20. The release layer 30 is a member that protects the curable resin layer 20 from being damaged and from the adhesion of foreign substances.

[0066] The release layer 30 is preferably formed from a resin film. Examples of the resin used for the resin film include cycloolefin resins, polyolefin resins such as polypropylene resins and polyethylene resins, ethylene vinyl acetate resins (EVA), polyester resins, polyamide resins, acrylonitrile butadiene styrene resins, polycarbonate resins, acrylic resins, fluororesins, vinyl chloride resins, tetrafluoroethylene resins, etc. Among these, cycloolefin resins, vinyl chloride resins, polyester resins, polypropylene resins, and polyethylene resins are preferable. Among these resins, polypropylene resins and polyethylene resins are more preferable, and polyethylene resin is even more preferable.

[0067] The polypropylene resin may be homopolypropylene or a copolymer of propylene and a small amount (for example, 10% by mass or less) of other α-olefins such as random polypropylene. Examples of other α-olefins include linear α-olefins having 1 to 12 carbon atoms such as ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-nonene, and 1-decene. Examples of the polyethylene resin include low-density polyethylene (LDPE, density: less than 0.930 g / cm 3 ), medium-density polyethylene (MDPE, density: 0.930 g / cm 3 or more and 0.942 g / cm 3Less than), high-density polyethylene (HDPE, density: 0.942 g / cm 3 Above), linear low-density polyethylene (LLDPE), etc. may be mentioned.

[0068] The resin film constituting the release layer 30 may be a single-layer film composed of a single layer, or may be a multilayer film of two or more layers. Further, in the resin film constituting the release layer 30, the resin contained in the resin film may be used alone or in combination of two or more. When two or more resins are used in combination, different types of resins may be used for each layer to form a multilayer film. Further, a single-layer film may be formed of a mixture of two or more resins, or one or more layers in a multilayer film may be formed. In the case of a multilayer film, it is preferable that at least one layer is either a polypropylene resin layer or a polyethylene resin layer, and more preferably a polyethylene resin layer. For example, as a multilayer film including a polyethylene resin layer, a multilayer film composed of a polyethylene resin layer and an EVA layer may be used. The resin film used for the release layer may be a stretched resin film or an unstretched resin film that has not been stretched, but an unstretched resin film is preferable.

[0069] The release layer 30 may be a release agent such as a silicone-based release agent or a fluorine-based release agent, and at least one surface thereof may be release-treated. When the release layer 30 is release-treated, the release-treated surface preferably constitutes the surface on the curable resin layer side. The release layer 30 can easily improve the peelability from the curable resin layer 20 by being release-treated. However, the release layer 30 does not necessarily need to be release-treated as long as it can be peeled from the curable resin layer 20. The thickness of the release layer 30 is not particularly limited, but is, for example, 10 μm or more and 1000 μm or less, preferably 30 μm or more and 700 μm or less, and more preferably 50 μm or more and 500 μm or less.

[0070] <Method for manufacturing a resin sheet> The method for manufacturing the resin sheet is not particularly limited, and it can be manufactured by known methods. For example, a curable resin composition is prepared, and the prepared curable resin composition is applied onto a support film and dried as necessary to form a curable resin layer. Further, when the resin sheet includes a release layer, the curable resin composition is applied onto the release layer and dried as necessary to form a curable resin layer, and a support film may be further laminated onto the curable resin layer formed on the obtained release layer to obtain a resin sheet. When applying the curable resin composition onto the support film or the release layer, the curable resin composition may be appropriately diluted with a solvent or the like. Examples of the solvent include ethyl acetate, butyl acetate, toluene, and the like. Further, when the curable resin layer is multilayered, it may be formed by sequentially forming and laminating each layer. For example, when having a clear layer and a colored layer, the colored layer and the clear layer may be laminated in this order onto the support film. Further, when the thermosetting resin sheet includes a release layer, a resin sheet may be obtained by laminating the colored layer formed on the support film and the clear layer formed on the release layer.

[0071] (Second Embodiment) Hereinafter, with reference to the drawings, the resin sheet of the second embodiment of the present invention will be described. As shown in Fig. 3, the resin sheet 1C of the second embodiment of the present invention includes a support film 10, a curable resin layer 20 made of a curable resin composition provided on the support film, and a primer layer 40 provided on the support film 10 on the curable resin layer side. The primer layer 40 contains at least one resin selected from the group consisting of an acid-modified polypropylene-based resin and a chlorinated polyolefin-based resin.

[0072] <Support Film> In the second embodiment, the resin constituting the support film 10 is not particularly limited as long as it has heat resistance against the molten resin used in injection molding, but is preferably a polyolefin resin, and more preferably a polypropylene resin. By using a polypropylene resin, the primer layer can be appropriately laminated on the support film. In addition, the heat resistance of the resin sheet is improved, and it can also be suitably used for injection molding using, for example, a polypropylene resin as the injection resin.

[0073] Details of the polyolefin resin and polypropylene resin used in the support film of the second embodiment are the same as those of the first embodiment, and thus the description thereof is omitted. In the support film of the second embodiment, the polypropylene resin is preferably the main component of the resin component constituting the support film, and may be, for example, 50 parts by mass or more and 100 parts by mass or less, preferably 70 parts by mass or more and 100 parts by mass or less, more preferably 85 parts by mass or more and 100 parts by mass or less, and most preferably 100 parts by mass, based on 100 parts by mass of the resin component. Note that the support film of the second embodiment typically does not contain an acid-modified polypropylene resin and a chlorinated polyolefin resin.

[0074] The thickness of the support film 10 is preferably 0.05 mm or more and 5 mm or less. When the thickness of the support film 10 is 0.05 mm or more, it is possible to further suppress the deterioration of the curable resin layer 20 due to the pressure and heat of the injected resin during injection molding. When the thickness of the support film 10 is 5 mm or less, the molding of the resin sheet 1C becomes easier. From such a viewpoint, the thickness of the support film 10 is more preferably 0.1 mm or more and 4 mm or less, and even more preferably 0.2 mm or more and 3 mm or less.

[0075] <Curable Resin Layer> The curable resin layer 20 in the resin sheet 1C is the same as the curable resin layer 20 in the resin sheet 1A of the first embodiment of the present invention, and thus the description of the curable resin layer 20 in the resin sheet 1C is omitted.

[0076] <Primer layer> The primer layer 40 contains at least one resin selected from the group consisting of an acid-modified polypropylene-based resin and a chlorinated polyolefin-based resin. Thereby, when the resin sheet 1C is integrated with a poorly adherent resin such as a polypropylene-based resin that is an injection resin simultaneously with injection molding, the adhesiveness of the resin sheet 1C to the poorly adherent resin such as the polypropylene-based resin becomes good.

[0077] <Acid-modified polypropylene-based resin> As the acid-modified polypropylene-based resin contained in the primer layer 40, the same one as the acid-modified polypropylene-based resin contained in the support film 10 of the resin sheet 1A of the first embodiment of the present invention can be used. Therefore, the description of the acid-modified polypropylene-based resin contained in the primer layer 40 is omitted.

[0078] <Chlorinated polyolefin-based resin> As the chlorinated polyolefin-based resin contained in the primer layer 40, the same one as the chlorinated polyolefin-based resin contained in the support film 10 of the resin sheet 1A of the first embodiment of the present invention can be used. Therefore, the description of the chlorinated polyolefin-based resin contained in the primer layer 40 is omitted.

[0079] The content of at least one resin selected from the group consisting of an acid-modified polypropylene-based resin and a chlorinated polyolefin-based resin in the primer layer 40 is preferably 50 parts by mass or more with respect to 100 parts by mass of the resin component. When the content of the above resin is 50 parts by mass or more, when integrated with a polypropylene-based resin simultaneously with injection molding, the adhesiveness of the resin sheet 1C to the polypropylene-based resin can be further improved. From such a viewpoint, the content of the above resin is more preferably 70 parts by mass or more, and still more preferably 80 parts by mass or more with respect to 100 parts by mass of the resin component. The upper limit value of the range of the content of the above resin with respect to 100 parts by mass of the resin component is 100 parts by mass, and the content of the above resin may be 100 parts by mass.

[0080] The primer layer 40 may contain resins other than acid-modified polypropylene resins and chlorinated polyolefin resins. From the perspective of adhesiveness with polypropylene resins, the primer layer 40 may contain, for example, polyolefin resins or polypropylene resins as resins other than acid-modified polypropylene resins and chlorinated polyolefin resins. The details of the polyolefin resins and polypropylene resins used in the primer layer of the second embodiment are the same as those of the polypropylene resins described in the first embodiment, so the description thereof is omitted.

[0081] The content of polypropylene resins other than acid-modified polypropylene resins and chlorinated polyolefin resins in the primer layer 40 is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, and still more preferably 20 parts by mass or less with respect to 100 parts by mass of the resin component. The lower limit value of the content range of polypropylene resins other than acid-modified polypropylene resins and chlorinated polyolefin resins in the primer layer 40 is not particularly limited, but is, for example, 0 parts by mass.

[0082] The thickness of the primer layer 40 is not particularly limited, but is, for example, 0.1 to 10 μm, and more preferably 0.5 to 5 μm.

[0083] <Release layer> As shown in FIG. 4, the resin sheet 1D may include a release layer 30 on the side opposite to the support film side of the curable resin layer 20. The release layer 30 is a member that protects the curable resin layer 20 from being damaged and from the adhesion of foreign substances. Since the release layer 30 of the resin sheet D is the same as the release layer of the sheet 1B, the description of the release layer 30 of the resin sheet D is omitted.

[0084] <Protective layer> As shown in FIG. 5, the resin sheet 1E may include a protective layer 50 on the side opposite to the primer layer side of the support film 10. The protective layer 50 is a member that protects the support film 10 from damage and foreign matter adhesion. The protective layer 50 is preferably formed of a resin film. Examples of the resin used for the resin film for the protective layer include thermoplastic resins. As the resin used for the resin film, the resins exemplified for the release layer can be appropriately selected and used. Preferably, cycloolefin resins, vinyl chloride resins, polyester resins, polypropylene resins, polyethylene resins, and the like can be mentioned. Among these resins, polypropylene resins and polyethylene resins are more preferable, and polyethylene resins are even more preferable.

[0085] The resin film forming the protective layer 50 may be a single-layer film composed of a single layer, or may be a multilayer film of two or more layers. Also, in the resin film constituting the protective layer 50, the resin contained in the resin film may be used alone or two or more kinds may be used in combination. In the case of a multilayer film, it is preferable that at least one layer is either a polypropylene resin layer or a polyethylene resin layer, and more preferably a polyethylene resin layer. For example, as a multilayer film including a polyethylene resin layer, a multilayer film composed of a polyethylene resin layer and an EVA layer may be used. The resin film used for the protective layer 50 may be a stretched resin film or an unstretched resin film without stretching, but an unstretched resin film is preferable.

[0086] The protective layer 50 may be a release agent such as a silicone-based release agent or a fluorine-based release agent, and at least one surface thereof may be subjected to a release treatment. When the protective layer 50 is subjected to a release treatment, the release-treated surface preferably constitutes the surface on the primer layer side. The protective layer 50 is easily peeled from the primer layer 40 by being subjected to a release treatment. However, the protective layer 50 does not necessarily need to be subjected to a release treatment as long as it can be peeled from the primer layer 40.

[0087] The thickness of the protective layer 50 is not particularly limited, but for example, it is 10 μm or more and 1000 μm or less, preferably 30 μm or more and 700 μm or less, and more preferably 50 μm or more and 500 μm or less.

[0088] <Method for manufacturing resin sheet> The method for manufacturing the resin sheet is not particularly limited, but it can be manufactured by a known method. For example, a curable resin composition and a support film having a primer layer formed by coating are prepared, and the prepared curable resin composition is coated on the primer layer and dried as necessary to form a curable resin layer. When the resin sheet includes a release layer, the curable resin composition may be coated on the release layer and dried as necessary to form a curable resin layer, and a support film having a primer layer may be laminated on the curable resin layer formed on the obtained release layer to obtain a resin sheet. When applying the curable resin composition to the support film or the release layer, the curable resin composition may be appropriately diluted with a solvent or the like. Examples of the solvent include ethyl acetate, butyl acetate, toluene, and the like. When the curable resin layer is multilayered, it may be formed by sequentially forming and laminating each layer. For example, when there is a clear layer and a colored layer, the colored layer and the clear layer may be laminated in this order on the support film. When the thermosetting resin sheet includes a release layer, a resin sheet may be obtained by laminating the colored layer formed on the support film and the clear layer formed on the release layer.

[0089] The resin sheet of the first embodiment of the present invention and the resin sheet of the second embodiment of the present invention are only examples of the resin sheet of the present invention, so the resin sheet of the first embodiment of the invention and the resin sheet of the second embodiment of the present invention do not limit the resin sheet of the present invention.

[0090] [Resin molded product] The resin molded product of the present invention includes the resin sheet of the present invention and a resin molded body integrated with the resin sheet of the present invention. The resin molded body is not particularly limited as long as it is obtained by molding a resin. However, from the viewpoint of being able to mold a product with a complex shape in a small number of steps and being able to continuously process it in a short cycle, the resin molded body is preferably a resin molded body molded by an injection molding method.

[0091] The resin constituting the resin molded body is not particularly limited as long as it can be molded by an injection molding method, but a thermoplastic resin is preferred. Examples of the thermoplastic resin that can be used as the resin member include ABS (acrylonitrile-butadiene-styrene) resin, polypropylene-based resin, PVC (polyvinyl chloride) resin, polyester-based resin, polycarbonate-based resin, and the like. These resins can be used alone or in combination of two or more. Since the resin sheet of the present invention has excellent adhesiveness to polypropylene-based resins, among these resins, polypropylene-based resins are preferred.

[0092] [Method for manufacturing a resin molded product] (First method for manufacturing a resin molded product) The first method for manufacturing a resin molded product of the present invention includes the following steps A and B. In step A, after heating and softening the resin sheet of the present invention, the resin sheet is vacuum molded using a vacuum molding die to produce a molded body of the resin sheet of the present invention. In step B, the molded body is inserted into an injection molding die, and the injection molding die is clamped, and a resin in a fluid state is injected into the cavity formed thereby to integrate the molded body and the injected resin on the support film side with respect to the curable resin layer. Hereinafter, with reference to the drawings, an example of the first method for manufacturing a resin molded product of the present invention will be described, but the first method for manufacturing a resin molded product is not limited to the method described below.

[0093] (Step A) In step A, after heating and softening the resin sheet, the resin sheet is vacuum molded using a vacuum molding die to produce a molded body of the resin sheet.

[0094] As shown in FIG. 6, the resin sheet 1 is placed in a vacuum forming machine 100 such that the curable resin layer 20 faces the heater side and the support film 10 faces the mold side, and the resin sheet is fixed with a clamp 130. Then, as shown in FIG. 6, the resin sheet 1 is heated using a heater 120 to soften the resin sheet 1. Next, as shown in FIG. 7, after the heater 120 is retracted, pressurized air (slightly pressurized air) is blown from below the laminate 3 to prevent the bottom thickness of the resin sheet 1 from becoming thick. Then, as shown in FIG. 8, the mold 110 moves upward, and the softened resin sheet 1 is pushed up by the mold 110 provided with a vacuum hole (not shown), vacuum-sucked, and brought into close contact with the surface to shape the resin sheet 1. As a result, the resin sheet 1 is shaped, and a molded body of the resin sheet 1 is produced. The temperature of the resin sheet during the shaping process is not particularly limited, but is preferably 90 to 200°C, more preferably 90 to 160°C.

[0095] Note that the heater 120 may be retracted during the shaping of the resin sheet 1 as long as the temperature of the resin sheet during the shaping process can be shaped within a predetermined range. Also, the heater 120 does not necessarily have to be retracted during the shaping of the resin sheet 1 as long as it can be shaped within the range of the shaping temperature described later.

[0096] (Step B) In Step B, the molded body is inserted into an injection mold, the injection mold is clamped, and a resin in a fluid state is injected into the cavity formed thereby, so that the molded body and the injected resin are integrated on the support film side with respect to the curable resin layer.

[0097] As shown in Fig. 9, the molded body 2 of the resin sheet produced in step A is inserted into the injection molds 210 and 220 of the injection molding machine 200. At this time, the molded body 2 is placed in the injection mold 210 so that the curable resin layer side of the molded body 2 contacts the injection mold 210. Among the injection molds 210 and 220, the injection mold 210 is a fixed mold, and the injection mold 220 is a movable mold. The injection mold 220 is provided with a resin inlet (gate) 221. The injection mold 220 is attached to a movable platen (not shown), and by moving the movable platen forward and backward, the injection molds 210 and 220 can be clamped or opened and closed. Then, as shown in Fig. 10, the injection molds 210 and 220 are clamped.

[0098] After clamping the injection molds 210 and 220, using an injection device (not shown), as shown in Fig. 11, the molten resin 240 is injected into the cavity 230 formed by clamping the injection molds 210 and 220. The injected resin is preferably heated, and its temperature is not particularly limited, but it is preferably 150 to 250 °C, and more preferably 170 to 230 °C. Normally, a hopper for feeding pellet-shaped resin material is provided above the injection device (not shown). In front of the injection device, there is a cylinder wound with a heater, and a screw for plasticizing the resin is inserted inside. The screw moves forward and backward by an injection cylinder at the center of the injection device and is rotationally driven by a hydraulic motor or an electric motor provided at the rear of the injection device. The entire injection device is usually installed on a gantry. This gantry can move forward and backward by a hydraulic cylinder for movement, and the nozzle attached to the tip of the cylinder is brought into contact with the injection mold 220 during injection and separated after injection.

[0099] After filling the cavity formed by clamping the injection molds 210 and 220 with the resin 240 in a flowing state, the resin 240 is pressure-held, cooled, and solidified. As a result, as shown in FIG. 12, on the support film 10 side with respect to the curable resin layer 20, the molded body 2 and the injected resin 240 are integrated. Then, the injection molds 210 and 220 are opened to take out the molded product. The sprue and the liner, which are unnecessary parts of the molded product, are cut off, and as shown in FIG. 13, a resin molded product 3 including the resin sheet 1 and the resin molded body 60 integrated with the resin sheet 1 is completed. Note that the molded product taken out from the injection molding machine may be further cured by heating or the like to further cure the resin sheet (curable resin layer). By heating and curing the resin sheet after molding, since the resin sheet is in an uncured or semi-cured and flexible state, and the shaping and injection molding are performed, it becomes easy to process the shape of the resin sheet into a desired shape.

[0100] In addition, when the curable resin layer of the resin sheet 1A is a thermosetting resin, it may be cured by being heated in a vacuum forming machine or an injection molding machine. For example, when cured inside a vacuum forming machine, after vacuum forming, the resin sheet may be thermally cured in the vacuum forming mold 110 while attached to the vacuum forming mold 110 as shown in FIG. 8. The heating temperature at this time is not particularly limited, but is preferably 100 to 200°C, and more preferably 120 to 180°C.

[0101] (Method for manufacturing a second resin molded product) The method for manufacturing the second resin molded product of the present invention includes the following steps A to C. In step A, the resin sheet of the present invention is heated and softened. In step B, the softened resin sheet is vacuum-sucked and adhered along the molding surface of the injection mold to perform preliminary molding. In step C, a resin in a flowing state is injected into the cavity formed by clamping the injection mold, and the resin sheet preliminarily molded on the support film side with respect to the curable resin layer and the injected resin are integrated. Hereinafter, with reference to the drawings, an example of the method for manufacturing the second resin molded product of the present invention will be described, but the method for manufacturing the second resin molded product is not limited to the method described below.

[0102] (Process A) In Process A, the resin sheet is heated and softened in the injection molding machine 200. For example, as shown in FIG. 14, after the resin sheet 1 is placed in the injection mold 210, a heater 250 may be placed between the injection mold 210 and the injection mold 220, and the resin sheet 1 may be heated and softened by the heater 250.

[0103] (Process B) In Process B, as shown in FIG. 15, the softened resin sheet 1 is vacuum-sucked and preliminarily molded by being brought into close contact along the molding surface of the injection mold 210. The molding surface of the injection mold 210 is provided with vacuum holes (not shown), and by vacuum-sucking, the resin sheet 1 can be brought into close contact with the surface. The temperature of the resin sheet during preliminary molding is not particularly limited, but is preferably 90 to 200°C, and more preferably 90 to 160°C.

[0104] (Process C) In Process C, the resin in a fluid state is injected into the cavity formed by clamping the injection mold, and the resin sheet preliminarily molded on the support film side and the injected resin are integrated with respect to the curable resin layer. Note that Process C is the same as Process B of the manufacturing method of the first resin molded product of the present invention except that the preliminarily molded resin sheet is used instead of the molded body, so the description of Process C is omitted.

[0105] Note that when the curable resin layer is a thermosetting resin, the resin sheet may be cured by being heated in the injection molding machine. For example, as shown in FIG. 16, the resin sheet 1 may be heated and thermally cured while being in close contact along the molding surface of the injection mold 210. Further, for example, the resin sheet 1 may be thermally cured by the resin injected in the injection mold. When the resin sheet is cured inside the injection molding machine, it is not necessary to be completely cured inside the injection molding machine, and it may be further cured by heating or the like after being taken out of the injection molding machine.

[0106] (Manufacturing Method of the Third Resin Molded Product) The manufacturing method of the third resin molded product of the present invention includes inserting the resin sheet of the present invention into an injection mold, clamping the injection mold, and injecting a resin in a fluid state into the cavity formed by clamping the injection mold, so as to integrate the resin sheet and the injected resin on the support film side with respect to the curable resin layer. Hereinafter, with reference to the drawings, an example of the manufacturing method of the third resin molded product of the present invention will be described, but the manufacturing method of the third resin molded product is not limited to the method described below.

[0107] As shown in FIG. 17, the resin sheet 1 is inserted into the injection molds 210 and 220 of an injection molding machine 200. At this time, the resin sheet 1 is arranged in the injection mold 210 so that the curable resin layer side of the resin sheet 1 is in contact with the injection mold 210. Note that the resin sheet 1 may or may not be molded. Then, as shown in FIG. 18, the injection molds 210 and 220 are clamped.

[0108] After the injection molds 210 and 220 are clamped, using an injection device (not shown), as shown in FIG. 19, a resin 240 in a fluid state is injected into the cavity 230 formed by clamping the injection molds 210 and 220. The injected resin is preferably heated, and its temperature is not particularly limited, but is preferably 150 to 250 °C, and more preferably 170 to 230 °C.

[0109] After the cavity formed by clamping the injection molds 210 and 220 is filled with the resin 240 in a fluid state, the resin 240 is pressure-held, cooled, and solidified. As a result, as shown in FIG. 19, the resin sheet 1 and the injected resin 240 are integrated on the support film 10 side with respect to the curable resin layer 20. Then, when the injection molds 210 and 220 are opened and the molded product is taken out, as shown in FIG. 20, a resin molded product 3 including the resin sheet 1 and a resin molded body 60 integrated with the resin sheet 1 is completed. Note that the molded product taken out from the injection molding machine may be heated or the like to cure the resin sheet 1 (curable resin layer). Further, when the curable resin layer of the resin sheet 1 is a thermosetting resin, it may be cured by being heated in an injection molding machine. The heating temperature at this time is not particularly limited, but is preferably 100 to 200°C, and more preferably 120 to 180°C.

[0110] The resin sheet and resin molded product of the present invention can be used for various applications. The resin sheet and resin molded product of the present invention are used, for example, in vehicles such as automobiles and transportation equipment other than automobiles, vehicle parts, electrical appliances, miscellaneous goods, heavy machinery, ships, aircraft, etc. for exterior materials, exterior walls or roof materials for houses and buildings, bridges, steel structures, plants, wind power generation blades, etc. Vehicle parts include, for example, vehicle interior materials and vehicle exterior materials. Among these, vehicles and vehicle parts are preferred, vehicle parts are more preferred, and vehicle exterior materials are even more preferred. Examples of exterior materials for vehicles include aerodynamic parts, hoods, roofs, door panels, bumpers, fuel filler panels, trunk lids, rear gates, etc.

[0111] [Vehicles, Vehicle Parts, Methods for Manufacturing Vehicles, and Methods for Manufacturing Vehicle Parts] The vehicle and vehicle parts of the present invention have the resin molded product of the present invention. Therefore, the method for manufacturing a vehicle of the present invention is a method for manufacturing a vehicle having a resin molded product, and the method for manufacturing a vehicle part of the present invention is a method for manufacturing a vehicle part having a resin molded product. And the method for manufacturing a vehicle of the present invention and the method for manufacturing a vehicle part of the present invention each include a step of manufacturing a resin molded product by the method for manufacturing a resin molded product of the present invention. Note that the step of manufacturing a resin molded product may be to manufacture a resin molded product by the method for manufacturing a resin molded product described above.

Examples

[0112] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited by these examples.

[0113] The evaluation method in this example is as follows. (Adhesion after injection molding) The evaluation of adhesion was carried out by a cross-cut test. A cutter knife was vertically applied to the test piece, and 11 parallel lines at equal intervals of 2 mm were drawn up to the interface to be evaluated. Then, 11 parallel lines at equal intervals of 2 mm intersecting these parallel lines were drawn, and 100 squares surrounded by four straight lines were drawn. The blade of the cutter knife used to make the scratches has a thickness of 0.3 to 0.5 mm, the acute angle of the blade tip is 18 to 25 degrees, it is made of carbon tool steel, the hardness is 820 ± 30 HV, a new blade tip is made by folding from the folding line, and it is used by holding it by hand (e.g., Erichsen cutter, NT cutter S type·A type (small)). Next, a peel test of the test piece with scratches on the cross-cut is carried out. In the standard state (23 ± 2 °C, humidity 50 ± 5 %), the adhesive tape was uniformly pressed with the belly of the finger on the surface of the test piece where the cross-cut was made so as not to contain air bubbles. At this time, the adhesive tape was not strongly pressed with the fingernail. One end of the adhesive tape was held and pulled suddenly to peel the tape from the test piece. The pulling direction was such that the angle formed by the test piece and the tape of the handle was 30 to 60 degrees. In principle, an adhesive tape with a semi-transparent pressure-sensitive adhesive with an adhesive strength of 10 ± 1 N / 25 mm was used as the adhesive tape. (e.g., Nichiban Sellotape (registered trademark) L pack 24). <Evaluation criteria> (1) Curing resin layer / Support film ◎: The number of squares with more than 50% peeling within the square is 0 out of 100 〇: The number of squares with more than 50% peeling within the square is 1 or more and 10 or less out of 100 ×: The number of squares with more than 50% peeling within the square is 11 or more out of 100 (2) Support film / Resin molded body ◎: The number of squares with more than 50% peeling within the square is 0 out of 100 〇: The number of squares with more than 50% peeling within the square is 1 or more and 10 or less out of 100 ×: The number of squares with more than 50% peeling within the square is 11 or more out of 100

[0114] The components of the release layer film, protective layer film, and curable resin layer used in the examples and comparative examples are as follows. <Release layer film and protective layer film> Convenience store PE: Unstretched polyethylene / EVA multilayer film ("Convenience store PE" manufactured by Okamoto Corporation, thickness 200 μm)

[0115] <Polyol resin> Acrylic polyol resin (1): Weight average molecular weight 250,000, hydroxyl value 80 mg KOH / g, solid content concentration (NV) = 23.3 mass% (solvent: ethyl acetate) Acrylic polyol resin (2): Weight average molecular weight 250,000, hydroxyl value 170 mg KOH / g, solid content concentration (NV) = 29.6 mass% (solvent: ethyl acetate)

[0116] <Plasticized resin> Polycarbonate diol: Hydroxyl value 204 - 244 mg KOH / g, weight average molecular weight 500, "PH-50", manufactured by UBE Industries, Ltd.

[0117] <Block isocyanate> Manufactured by Mitsui Chemicals, Inc., "Takenate B-882N", hexamethylene diisocyanate-based block isocyanate curing agent (HDI-based), blocking agent type: 3,5-dimethylpyrazole (DMP), solid content concentration (NV) = 70%, solvent is petroleum naphtha, thermal dissociation temperature = 120 °C

[0118] <Urethanization catalyst> "XK-639", manufactured by Kusumoto Chemicals, Ltd., solid content concentration (NV) = 100%

[0119] <Pigment (colorant)> "NSP-UP 841B" manufactured by Nichihon Binks Co., Ltd., effective pigment concentration = 9 mass%, solid content concentration (NV) = 9.0 mass%, solvent is MEK

[0120] <Pearlescent pigment (colorant)> "Xirallic T60-10 WNT Crystal Silver" manufactured by Merck KGaA, solid content concentration (NV) = 100 mass%

[0121] The components of the support film, primer layer, and injection molding resin used in the examples and comparative examples are as follows. h-PP (homopolypropylene): manufactured by Sun Allomer Co., Ltd., product name "PM600A", density 0.9 g / cm 3 , MFR 7.5 g / 10 min ABS (acrylonitrile-butadiene-styrene) resin: ABS, product name "Toyolac 700-314U", density 1.05 g / cm 3 , MFR 23 g / 10 min Modified PP (acid-modified polypropylene resin 1): manufactured by Nippon Paper Industries Co., Ltd., product name "Auroren 350S", melting point 65-75 °C Chlorinated PP (chlorinated polypropylene resin 1): manufactured by Nippon Paper Industries Co., Ltd., product name "Super Kron 822S", chlorine content 23.5-25.5 mass%

[0122] (Examples 1-5, Comparative Examples 1, 2) [Preparation of Support Film and Primer Layer] The raw materials were charged into an extrusion molding machine in the formulation shown in Table 2, melt-kneaded, and extruded from a die to obtain a support film. For the primer layer, a resin composition with a solid content concentration of 15 mass% prepared in the formulation shown in Table 2 and diluted with methylcyclohexane / methyl ethyl ketone = 8 / 2 in the case of modified PP was applied onto the surface of the support film with an applicator, and then dried under the conditions of 90 °C for 60 minutes to form a primer layer with a thickness of 5 μm on the support film. In the case of chlorinated PP, a resin composition with a solid content concentration of 15 mass% diluted with toluene was applied onto the support film with an applicator, and then dried under the conditions of 100 °C for 60 minutes to form a primer layer with a thickness of 5 μm on the support film.

[0123] [Preparation of Thermosetting Resin Compositions A and B] Each component was added in the formulation as shown in Table 1, and ethyl acetate was added as a solvent to prepare paints for curable resin compositions A and B with a solid content concentration of 30 mass%.

[0124] [Preparation of Curable Resin Layer Sheet] After applying the thermosetting resin composition A on the surface of the film for the release layer using an applicator, a pre-drying process was carried out under the conditions of a drying temperature of 60 °C and a drying time of 30 minutes, and then the main drying process was carried out under the conditions of a drying temperature of 90 °C and a drying time of 30 minutes to form a clear layer with a thickness of 30 μm on the release layer. Next, after applying the thermosetting resin composition B on the surface of the support film using an applicator, a pre-drying process was carried out under the conditions of a drying temperature of 60 °C and a drying time of 30 minutes, and then the main drying process was carried out under the conditions of a drying temperature of 90 °C and a drying time of 30 minutes to form a colored layer with a thickness of 30 μm on the film for the support layer. When a primer layer was provided on the support film, the thermosetting resin composition B was applied on the surface opposite to the surface provided with the primer layer. The clear layer on the release layer and the colored layer on the support film were laminated and laminated at 25 °C to obtain a resin sheet laminated in the order of the release layer, the clear layer, the colored layer, and the support film.

[0125]

Table 1

[0126]

Table 2

[0127] In the resin molded articles of Examples 1 to 5, since the support film contained an acid-modified polypropylene-based resin, the adhesiveness of the resin sheet to the resin molded body was good. The resin molded articles of Examples 6 and 7 were provided with a primer layer containing at least one resin selected from the group consisting of an acid-modified polypropylene-based resin and a chlorinated polyolefin-based resin, so the adhesiveness of the resin sheet to the resin molded body was good. The resin molded articles of Comparative Example 1 and Comparative Example 2 do not contain at least one resin selected from the group consisting of an acid-modified polypropylene resin and a chlorinated polyolefin resin in the support film, and there is no primer layer. As a result, the curable resin layer peeled off from the support film, or the support film peeled off from the resin molded article, and as a result, the resin sheet could not be adhered to the resin molded body.

Explanation of Signs

[0128] 1,1A~1E Resin sheet 2 Molded body 3 Resin molded article 10 Support film 20 Curable resin layer 30 Release layer 40 Primer layer 50 Protective layer 60 Resin molded body 100 Vacuum forming machine 110 Mold (vacuum forming mold) 120,250 Heater 130 Clamp 200 Injection molding machine 210,220 Injection molding mold 221 Resin inlet (gate) 230 Cavity 240 Resin

Claims

1. A resin sheet comprising a support film and a curable resin layer made of a curable resin composition provided on the support film, wherein the support film contains at least one resin selected from the group consisting of an acid-modified polypropylene-based resin and a chlorinated polyolefin-based resin, or the resin sheet further comprises a primer layer provided on the support film on the curable resin layer side, and the primer layer contains at least one resin selected from the group consisting of an acid-modified polypropylene-based resin and a chlorinated polyolefin-based resin.

2. The resin sheet according to claim 1, wherein the acid-modified polypropylene-based resin is a copolymer of propylene or propylene and ethylene and at least one unsaturated carboxylic acid selected from the group consisting of maleic anhydride, itaconic acid, fumaric acid, oleic acid, acrylic acid, and methacrylic acid.

3. The resin sheet according to claim 1, wherein the chlorinated polyolefin-based resin is at least one resin selected from the group consisting of chlorinated polypropylene, chlorinated ethylene-propylene copolymer, chlorinated propylene-butene copolymer, and chlorinated ethylene-propylene-butene copolymer.

4. The resin sheet according to claim 1, wherein the ratio of the thickness of the support film to the thickness of the resin sheet is 30% or more.

5. The resin sheet according to claim 1, wherein the curable resin composition is a thermosetting resin composition.

6. A resin molded article comprising the resin sheet according to any one of claims 1 to 5 and a resin molded body integrated with the resin sheet.

7. A vehicle having the resin molded article according to claim 6.

8. A vehicle part having the resin molded article according to claim 6.

9. A method for manufacturing a resin molded article, comprising inserting the resin sheet according to any one of claims 1 to 5 into an injection molding die, closing the injection molding die, injecting a resin in a fluid state into a cavity formed by closing the die, and integrating the resin sheet and the injected resin on the support film side with respect to the curable resin layer.

10. A step of heating and softening the resin sheet according to any one of claims 1 to 5, then vacuum molding the resin sheet using a vacuum molding die to produce a molded body of the resin sheet, and A method for manufacturing a resin molded article, comprising a step of inserting the molded article into an injection mold, clamping the injection mold, injecting a resin in a fluid state into a cavity formed by the clamping, and integrating the molded article and the injected resin on the support film side with respect to the curable resin layer.

11. The curable resin composition of the resin sheet is a thermosetting resin composition, The method for manufacturing a resin molded article according to claim 10, wherein the resin sheet is thermally cured in the vacuum mold, or the resin sheet is thermally cured by the resin injected in the injection mold, or the resin sheet is thermally cured by both of these.

12. A step of heating and softening the resin sheet according to any one of claims 1 to 5, a step of pre-molding by vacuum suctioning the softened resin sheet and adhering it along the molding surface of the injection mold, and A method for manufacturing a resin molded article, comprising a step of injecting a resin in a fluid state into a cavity formed by clamping the injection mold, and integrating the resin sheet pre-molded on the support film side with respect to the curable resin layer and the injected resin.

13. The curable resin composition of the resin sheet is a thermosetting resin composition, The method for manufacturing a resin molded article according to claim 12, wherein the resin sheet is thermally cured when it is adhered along the molding surface of the injection mold, or the resin sheet is thermally cured by the resin injected in the injection mold, or the resin sheet is thermally cured by both of these.

14. A method for manufacturing a vehicle having a resin molded article, comprising A method for manufacturing a vehicle, including a step of manufacturing the resin molded article by the method for manufacturing a resin molded article according to claim 9.

15. A method for manufacturing a vehicle part having a resin molded article, comprising A method for manufacturing a vehicle part, including a step of manufacturing the resin molded article by the method for manufacturing a resin molded article according to claim 9.

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