JP2002127182A - Method for producing sheet for simultaneous decoration with injection molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a sheet for simultaneous decoration with injection molding which has moldability and a feel of coating with an acrylic resin used for a base material sheet to be excellent in scratch resistance as well as solvent resistance. SOLUTION: On the surface side of the base material sheet 1 of the thermoplastic acrylic resin, a solvent resistant layer 2 of a cured two-component acrylic resin, cured by a silane coupling agent, is laminated by transfer to produce the sheet S for simultaneous decoration with injection molding. A backing base material layer of a polyolefin resin can be formed on the back side of the base material sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a laminate type painting sheet used for simultaneous painting by injection molding.
The present invention relates to a method for producing a sheet for painting, which has sufficient moldability and can also have good scratch resistance in addition to solvent resistance.

[0002]

2. Description of the Related Art As a method for producing a painted product in which the surface of a resin molded product is painted, there is known an injection molding simultaneous painting method disclosed in Japanese Patent Publication No. 50-19132, Japanese Patent Application Laid-Open No. Hei 11-91041, and the like. I have. In the simultaneous painting method of injection molding, a molded sheet can be obtained by simultaneously laminating and painting a sheet for painting on the surface of the resin molded article at the same time as molding. Various resin sheets such as ABS resin, polyolefin-based resin, and acrylic resin are used as the base sheet of the sheet for simultaneous painting with injection molding used according to the application. Above all, acrylic resin is excellent in transparency, so that a highly designed painting feeling can be obtained.

[0003]

However, when an acrylic resin is used for the substrate sheet, the layer structure of the sheet for simultaneous injection molding and painting such that the outermost surface becomes the substrate sheet when the molded article is formed, In some cases, the surface has insufficient organic solvent resistance (hereinafter, simply referred to as “solvent resistance”). The problem of the solvent resistance is that a solvent-resistant layer is formed on the acrylic resin base sheet by applying a coating liquid containing an organic solvent on the base sheet so as to impart the solvent resistance. In this case, there is also a self-contradictory problem such that a part of the base sheet is dissolved or swelled by the solvent depending on the solvent used.
Further, when an acrylic resin was used for the base sheet, the scratch resistance of the surface was not so good. In this regard, if polycarbonate resin is used for the base sheet,
Although the abrasion resistance is improved, the stability of the molding process tends to decrease and the cost tends to increase. Moreover,
The solvent resistance was not much different from the acrylic resin.

[0004] That is, an object of the present invention is to provide a method for producing a sheet for simultaneous painting with injection molding, which can obtain excellent coating feeling and moldability, and also has good scratch resistance in addition to solvent resistance. Is the thing.

[0005]

Therefore, in order to solve the above-mentioned problems, in the method for producing a sheet for simultaneous painting with injection molding according to the present invention, an acrylic resin is coated on a surface side of a base sheet made of a thermoplastic acrylic resin. A solvent-resistant layer made of a cured product of a two-component curable acrylic resin cured by a coupling agent was laminated by transfer.

[0006] By laminating such a solvent-resistant layer made of a cured product of a specific material onto a substrate sheet by transfer, even if the solvent-resistant layer is a cured product layer, a sheet for simultaneous painting with injection molding is provided. While the required moldability is maintained, the obtained sheet for simultaneous painting with injection molding has not only solvent resistance but also scratch resistance. In addition, since the solvent-resistant layer is laminated on the base sheet by transfer, the base sheet is dissolved by an organic solvent in the paint when the solvent-resistant layer is formed by coating. No damage.

[0007] The method for producing a sheet for simultaneous painting with injection molding according to the present invention further comprises a backing made of a polyolefin resin on the back side of the base sheet before or after lamination of the solvent-resistant layer. The base material layer was laminated.

As described above, if the backing base layer of the polyolefin resin is provided on the back side of the base sheet, the sheet for simultaneous injection molding with good adhesion to the inexpensive polyolefin resin as the injection molding resin can be obtained. Is obtained. In addition, the total thickness required for the sheet for simultaneous painting with injection molding is shared with the backing base layer made of inexpensive polyolefin resin in addition to the base sheet made of expensive acrylic resin. Can be manufactured.

[0009]

Embodiments of the present invention will be described below.

[Summary] First, the structure of a sheet for simultaneous painting with injection molding obtained by the method for producing a sheet for simultaneous painting with injection molding according to the present invention has the simplest structure. Base sheet 1 such as painting sheet S
And a two-component curable acrylic resin obtained by curing the acrylic resin with a silane coupling agent on the front side of the base sheet 1 made of a thermoplastic acrylic resin. This is a configuration in which the solvent-resistant layer 2 is laminated as a transfer layer 4 by transfer.

In the manufacturing method of the present invention, the solvent-resistant layer 2 formed by coating in advance and evaporating and drying the organic solvent in the coating has already been laminated on the base sheet 1 by transfer. By doing so, it is possible to prevent the occurrence of damage to the base sheet such as dissolution of the base sheet by an organic solvent, which is a problem when the solvent-resistant layer 2 is laminated by a direct coating method. The transfer of the solvent-resistant layer 2 may be performed by a known transfer method. For example, as shown conceptually in FIG. 1, the solvent-resistant layer 2 has a transfer layer 4 on a support sheet 3. A transfer sheet T is prepared, and a pressure or a normal heat pressure is applied thereto by a transfer roller R in which the surface of an iron core is covered with an elastic body such as silicone rubber to transfer the transfer layer including the solvent-resistant layer 2 from the transfer sheet T. 4
What is necessary is just to transfer to the base material sheet 1. In this way, the solvent-resistant layer made of the cured product imparts solvent resistance and also abrasion resistance to the surface of the sheet for simultaneous painting with injection molding using the acrylic resin for the base sheet. Can be.

As the sheet for simultaneous painting with injection molding to be manufactured, a decorative layer or the like for expressing a printed pattern or the like is usually provided below the solvent-resistant layer 2 in order to further enhance the design. For example, as illustrated in FIG.
Between the substrate and the solvent-resistant layer 2 or the base sheet 1
On the back side (injection molding resin side) (not shown). In this case, the layer closer to the observer than the decorative layer such as the solvent-resistant layer and the base sheet is transparent so that the decorative layer expressing the design or the like can be seen through. As illustrated in FIG. 2, a backing base material layer 5 made of a polyolefin resin may be laminated on the back surface side of the base material sheet 1. In the case of the figure,
It is the figure which illustrated the case where the backing base material layer 5 is laminated | stacked beforehand on the base material sheet 1 before the transfer layering of the solvent resistance layer 2. FIG. The lamination of the backing substrate layer 5 may be performed by a known lamination method such as a melt coating method.

Hereinafter, the present invention will be described in more detail.

[Base Sheet] As the base sheet 1, a resin sheet made of a thermoplastic acrylic resin is used. Examples of the thermoplastic acrylic resin include polymethyl (meth) acrylate, polyethyl (meth) acrylate,
Acrylic resins such as polybutyl (meth) acrylate, methyl (meth) acrylate-butyl (meth) acrylate copolymer, ethyl (meth) acrylate-butyl (meth) acrylate copolymer, methyl (meth) acrylate-styrene copolymer [However, (meth) acrylate means acrylate or methacrylate] is used alone or as a mixture of two or more. The base sheet is used as a sheet of a single layer or a laminate of two or more layers made of these acrylic resins. The thickness of the base sheet is not particularly limited and depends on the application, but is about 30 to 500 μm, generally about 5 μm.
It is about 0 to 250 μm. The base sheet may be opaque (colored or non-colored) in addition to transparent, depending on the application. When the decorative layer for expressing a design or the like is on the back side of the base material sheet, it is transparent, but when the decorative layer is on the front side of the base material sheet, it can be opaque. In addition,
In order to color the base sheet (transparent or opaque), a known coloring agent or the like described in the decorative layer described later may be kneaded in the resin.

[Solvent-Resistant Layer] The solvent-resistant layer 2 is formed on the front side of a substrate sheet by transfer as a layer composed of a cured product of a two-component curable acrylic resin obtained by curing an acrylic resin with a silane coupling agent. . The solvent-resistant layer 2 is usually formed as a transparent layer so that the decorative layer and the like can be seen through.
The solvent resistance can be imparted to the surface by the solvent resistance layer. The solvent-resistant layer can also impart abrasion resistance. As a main component of the two-component curable acrylic resin, one or two or more functional groups having reactivity with a silane coupling agent such as a hydroxyl group or a carboxyl group are usually introduced in a molecule by two or more. Acrylic resin can be used. For example, when the functional group is two or more hydroxyl groups, the acrylic resin can also be called an acrylic polyol. Such hydroxyl-containing acrylic resins include, for example, methyl (meth) acrylate,
Ethyl (meth) acrylate, (meth) acrylic acid-n-
Propyl, isopropyl (meth) acrylate, (meth)
One or two or more alkyl (meth) acrylate monomers such as n-butyl acrylate, isobutyl (meth) acrylate, octyl (meth) acrylate, ethylhexyl (meth) acrylate; (Meth) acrylic acid ester having a hydroxyl group in the molecule such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-hydroxy-3-phenoxypropyl (meth) acrylate A copolymer obtained by copolymerizing one or more kinds of the monomer and, if necessary, another vinyl monomer such as a styrene monomer is exemplified. In addition, (meth) acrylic acid means acrylic acid or methacrylic acid. When a carboxyl group is introduced, a copolymer obtained by copolymerizing a carboxyl group-containing vinyl monomer such as acrylic acid or methacrylic acid is used.

As the silane coupling agent serving as a curing agent, a known silane coupling agent having an amino group, a vinyl group, an epoxy group, a mercapto group, a chloro group and the like in addition to an alkoxy group may be used depending on the application. You can use it. For example, γ-aminopropyltriethoxysilane,
γ-methacryloxypropyltrimethoxysilane, γ-
Methacryloxypropylmethyldimethoxysilane, γ-
Methacryloxypropyldimethylmethoxysilane, γ-
Methacryloxypropyltriethoxysilane, γ-methacryloxypropyldimethylethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropylmethyldimethoxysilane, γ-acryloxypropyldimethylmethoxysilane, γ-acryloxypropyltriethoxy Silane, γ-acryloxypropylmethyldiethoxysilane, γ-acryloxypropyldimethylethoxysilane, vinyltriethoxysilane, γ
-Glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane and the like. In addition,
The addition amount of the silane coupling agent as the curing agent is about 5 to 15% by mass based on the acrylic resin as the main component.

Incidentally, a powder filler may be further added to the solvent-resistant layer. By adding the powder filler, the scratch resistance can be further improved. As the powder filler,
Inorganic or organic powder is used. In order to impart abrasion resistance due to the hardness of the resin of the solvent-resistant layer and its hardness, an inorganic substance is more easily applied than an organic substance such as resin beads. Examples of the inorganic powder filler include oxides of metals such as aluminum, titanium, silicon, zirconium, and magnesium, glass, calcium carbonate, and diamond. Specifically, for example, alumina such as α-alumina is used. Such powder fillers are, for example,
The average particle size is 2-3 μm, and the minimum value of the particle size distribution is 0.01 μm.
m, those having a maximum value within the range of 6 μm are preferred in that good scratch resistance can be obtained. The particle shape of the powder filler may be spherical, scaly, polyhedral or the like. The amount of the powder filler depends on the required physical properties.
Usually, about 0.1 to 50 parts by mass, more preferably 5 to 30 parts by mass, per 100 parts by mass of the two-component curable acrylic resin.
It is about parts by mass. In the present invention, the silane coupling agent is used as the curing agent, so that when the above-described metal oxide or the like is used as the powder filler, the silane coupling agent is also reacted with the powder filler, and A solvent-resistant layer in which a filler is firmly bonded and dispersed in a binder resin can also be used.

In the solvent-resistant layer, in addition to the above-mentioned powder filler, a lubricant such as silicone resin and wax, an ultraviolet absorber such as benzotriazole, benzophenone and fine particle cerium oxide, and a hindered amine radical scavenger. Known additives such as light stabilizers, extenders, coloring agents, and the like can be used as appropriate.

[Transfer formation of solvent-resistant layer, etc.] Solvent-resistant layer 2
Is laminated by a transfer method in the present invention. That is, as illustrated in FIG. 1, the solvent-resistant layer 2 is formed by temporarily forming the solvent-resistant layer 2 as a transfer layer 4 on a support sheet 3 to form a transfer sheet T, and then transferring the transfer layer As 4, transfer is formed on the base sheet 1.
The method of forming the solvent-resistant layer 2 on the support sheet 3 is performed by using a coating liquid (or ink) containing a two-part curable acrylic resin composed of the silane coupling agent and the acrylic resin.
It may be formed by a known coating method such as roll coating or a known printing method such as gravure printing. The type of the transfer pressure is not particularly limited, but the transfer target is a flat base sheet (sheet-like or continuous belt-like) unlike the resin molded product, and therefore, for example, a conventional roller transfer method is sufficient. In the roller transfer method, a transfer pressure is applied to a transfer sheet using an elastic roller (rubber roller) whose surface such as an iron core is covered with an elastic material such as silicone rubber as a transfer roller. Further, the roller is usually heated by infrared radiation or an internal electric heater or the like, and the transfer is performed using both the transfer pressure and the heating. Therefore, the transfer layer is adhered to the transfer target (base sheet) by heat fusion by heating. In addition, if the transfer layer exhibits adhesiveness even at normal temperature, heating is not necessarily essential for transfer.

Here, the structure of the transfer sheet that can be used for forming the solvent-resistant layer will be further described.

The support sheet 3 is not particularly limited as long as it is a sheet having releasability from the transfer layer. For example, the formability required for the sheet for simultaneous painting with injection molding may or may not be required. Therefore, a known sheet of a transfer sheet can be used as the support sheet.
For example, polyethylene terephthalate, polybutylene terephthalate, ethylene terephthalate-isophthalate copolymer, polyarylate, polyester resin such as polyester-based thermoplastic elastomer, polyethylene, polypropylene, polymethylpentene, polyolefin resin such as olefin-based thermoplastic elastomer, nylon 6, resin sheet (film) made of polyamide such as nylon 66, vinyl chloride resin, vinyl polymer such as ethylene-vinyl alcohol copolymer, vinylon, or the like, or separation of high quality paper, tissue paper, etc. with polyolefin resin or silicone resin. Paper such as coated paper, glassine paper, parchment paper, etc. on which a mold layer is laminated. The thickness of the support sheet is usually 10
About 100 μm.

In the support sheet, a release layer may be provided as a component of the support sheet on the transfer layer side in order to improve the releasability from the transfer layer. When a release layer is provided, the support sheet (with a release layer) has a configuration in which the above-described support sheet is used as a material sheet and a release layer is laminated on this material sheet. When the support sheet is separated from the transfer layer, the release layer separates from the transfer layer as a part of the support sheet and is separated and removed from the transfer layer moving to the base sheet. As the release layer, for example, a simple substance such as a silicone resin, a melamine resin, a polyester resin, a polyamide resin, a urethane resin, a polyolefin resin, a wax, or a mixture containing these is used.

Further, if the surface of the support sheet on the transfer layer side is provided with a concavo-convex pattern, a concavo-convex pattern such as grain, pear, wood grain, etc. is formed on the surface of the transfer layer after transfer, and the surface gloss is adjusted. You can also do. The concavo-convex pattern is formed by a known method such as embossing, sand blasting, and embossing printing with a shaping layer (release layer) (see release layer 3B in FIG. 4A).

The transfer sheet T used for the transfer formation of the solvent-resistant layer 2 includes a transfer layer 4 as the solvent-resistant layer 2
Other layers may be provided. For example, FIGS. 3 and 4
As exemplified in the above, the release layer 6 is provided in contact with the support sheet to adjust the releasability between the support sheet and the transfer layer, or the decorative layer 7 described later.

As the release layer 6, for example, polymethyl (meth) acrylate, polybutyl (meth) acrylate, methyl (meth) acrylate-butyl (meth)
Acrylic resin such as acrylate copolymer, vinyl chloride
Resins such as vinyl acetate copolymers and cellulose resins are used. The release layer may be formed by a known forming method such as gravure printing. In addition, the thickness of the release layer may be small from the viewpoint that the surface protection is not intended and the effect of the solvent-resistant layer which is the lower layer in the painted product is exhibited. For example, the thickness of the release layer is 0.1 to 4 μm or the like.

[Decoration Layer] The sheet for simultaneous painting with injection molding to be manufactured may be composed of the base sheet 1 and the solvent-resistant layer 2, for example, if the base sheet is a colored sheet, the surface of the adherend is colored. It becomes a sheet for painting to be decorated. But,
Normally, the decorative layer 7 is formed by printing or the like, for example, as shown in FIG. As described above, the decorative layer is preferably formed by transfer for the same reason as the solvent-resistant layer.

The decorative layer 7 is typically a layer for expressing a pattern such as a pattern or a character. The pattern is arbitrary, for example,
Wood grain, stone grain, cloth grain, sand grain, geometric pattern, letters, solid color, etc.

A typical method of forming the decorative layer 7 is a method of forming by printing with ink. The ink may be appropriately selected from known ones in consideration of adhesiveness and the like. For example, as a resin for the binder of the ink, an acrylic resin, a vinyl chloride-vinyl acetate copolymer, a polyester resin, a polyurethane resin, or the like may be used alone or in combination of two or more. Examples of the coloring agent to be contained in the ink include inorganic pigments such as titanium white, zinc white, carbon black, iron black, red iron oxide, cadmium red, ultramarine, cobalt blue, graphite, and titanium yellow, phthalocyanine blue, and Indus Organic pigments such as renblue, isoindolinone yellow, quinacridone red and perylene red; metal pigments such as aluminum and brass and metal pigments such as scales; pearlescent (pearl) pigments such as titanium dioxide-coated mica powder and scales; Alternatively, a dye or the like is used.

The decorative layer may be, for example, a metal thin film layer formed by vapor deposition of aluminum, chromium or the like or formed entirely or partially. In this case, since there is no problem of solvent resistance, it is preferable to directly form on the base sheet in addition to forming on the base sheet by transfer from the transfer sheet.

The positional relationship between the decorative layer and the solvent-resistant layer is as follows.
In the transfer sheet, the decorative layer is positioned farther from the support sheet side with respect to the solvent-resistant layer, that is, the decorative layer is positioned below the solvent-resistant layer when the molded article is formed. Is preferred in that the decorative layer can be protected by the solvent-resistant layer (see FIG. 4). Note that the decorative layer may be provided on the back surface side (resin molded product side) of the base sheet. In this case, it is necessary to make the decoration layer resin content, injection conditions, sheet configuration, and the like such that the decoration layer does not flow and the pattern does not collapse with the injection resin heated and melted at the time of resin injection. For example, in the sheet configuration, a decorative layer is provided between the base sheet and the backing base layer, between the base sheet and the back adhesive layer, and the like. By providing the decorative layer on the back surface side of the base sheet, a richer coating feeling can be imparted by utilizing the thickness of the transparent base sheet.

(Primer layer) In the transfer layer, the layer in contact with the base sheet, that is, in the case where the transfer layer also has a solvent-resistant layer or a decoration layer, the decoration layer has poor adhesion to the base sheet. In this case, in order to improve the adhesiveness between the transfer layer and the base sheet, the primer layer 8 as a layer in contact with the base sheet among the transfer layers as illustrated in FIGS.
May be provided. For the primer layer 8, for example, a conventionally known thermoplastic resin having heat fusion properties can be used. For example, thermoplastic resins such as vinyl acetate resin, vinyl chloride-vinyl acetate copolymer, acrylic resin, thermoplastic polyester resin, polyamide resin, ionomer, and chlorinated polyolefin. The primer layer may be formed by a known printing method (or coating method) such as gravure printing (or roll coating) using an ink (or coating liquid) made of the above resin. The thickness of the primer layer is not particularly limited, but is usually about 1 to 100 μm.

[Backing Substrate Layer] The backing substrate layer 5 is provided as a layer composed of a polyolefin resin. When the resin of the adherend of the sheet for simultaneous painting with injection molding is a polyolefin resin, It is preferable to provide this backing substrate layer 5 in terms of adhesion to an adherend. By providing the backing substrate layer, the adhesiveness to a polyolefin resin which is inexpensive as a molding resin is improved, and a sheet for simultaneous painting with injection molding corresponding to the polyolefin resin can be manufactured. Also, together with the base sheet made of expensive acrylic resin, by sharing the thickness of the sheet necessary to secure the moldability and handleability of the sheet for simultaneous painting with injection molding,
The sheet for simultaneous painting with injection molding can be manufactured at low cost.

In order to laminate the backing substrate layer 5 to the substrate sheet 1, a known lamination method such as a melt extrusion coating method using a T-die, a multi-layer simultaneous extrusion method such as a two-layer method, or a doiler lamination method. Good. However, the adhesive used at the time of dry lamination should be applied to the resin sheet side as the backing base layer in order to avoid the problem of solvent resistance of the base sheet, or if applied to the base sheet side, use an aqueous adhesive. It is preferable to use.

The polyolefin resin used for the backing base material layer 5 is a resin capable of obtaining adhesiveness to the adherend according to the resin material of the adherend to be laminated on the sheet for simultaneous painting with injection molding. There is no particular limitation. For example, polyethylene, polypropylene, polybutene, polymethylpentene, ethylene-propylene copolymer, ethylene-propylene-butene copolymer, olefin-based thermoplastic elastomer, acrylic-modified polyolefin-based resin and the like by one kind, or two or more kinds Used as a mixture. As the polyolefin-based resin, a resin having a hydroxyl group, a carboxyl group, or the like as a polar group in a resin molecule for improving adhesion is also preferable. For example, a resin having a hydroxyl group introduced by graft polymerization of an ethylene-vinyl alcohol copolymer or a resin having a carboxyl group introduced by copolymerization of maleic acid, fumaric acid, itaconic acid, or the like. Further, from the viewpoint of adhesion to a substrate sheet made of an acrylic resin, an acrylic-modified polyolefin-based resin which is a resin obtained by modifying a polyolefin-based resin with an acrylic monomer (or a prepolymer as a polymer of the monomer) is preferable. At this time, if polar groups such as a hydroxyl group and a carboxyl group are also introduced, a resin having improved adhesion of the polyolefin resin to the adherend can be obtained.

[Back adhesive layer] When the resin of the adherend is a polyolefin-based resin, it is preferable to provide the above-mentioned backing substrate layer from the viewpoint of adhesion to the adherend. When the resin of the adherend is a resin other than the polyolefin-based resin, a back adhesive layer 9 may be provided according to the adherend resin as illustrated in FIGS. 3 and 4. The back adhesive layer is provided before or after laminating the solvent-resistant layer on the base sheet.
As the resin of the back adhesive layer, for example, a conventionally known thermoplastic resin, thermosetting resin, or the like may be used. For example, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer, acrylic resin, thermoplastic polyester resin, polyamide resin, ionomer, thermoplastic resin such as chlorinated polyolefin,
Thermosetting resins such as two-component curable urethane resins and epoxy resins. In addition, even when the resin of the adherend is a polyolefin-based resin, the backing adhesive layer may be provided without providing the backing base material layer. Unlike the backing substrate layer, the backside adhesive layer does not need to share the necessary thickness as a sheet for simultaneous painting with injection molding. Therefore, the thickness of the back surface adhesive layer is usually about 1 to 20 μm. In addition, the back surface adhesive layer is formed by a known printing method or coating method using an ink or a coating liquid composed of the above resin.

[Injection Simultaneous Painting Method] The injection molding simultaneous painting method, which is a use of the sheet for simultaneous injection molding painting of the present invention, will now be briefly described.

The simultaneous painting method for injection molding is described in
No. 19132, Japanese Patent Publication No. 43-27488, etc., after arranging the sheet for simultaneous painting with injection molding between the male and female dies of injection molding, the resin in the fluid state is injected and filled into the mold, This is a method in which a sheet for painting simultaneously with injection molding is laminated on the surface of a resin molded product and painted at the same time.

In the simultaneous injection molding painting method, various forms in the conventionally known simultaneous injection molding painting method are possible. For example, the pre-forming of the painting sheet may or may not be performed. Further, the prepainting sheet may or may not be preheated. In addition, the sheet for painting is usually preheated at the time of preforming.

Of course, if the drawing sheet has a large drawing, it is preferable to perform preforming. On the other hand, when the drawing sheet has a small amount of drawing, the drawing sheet may be formed only by the resin pressure of the resin in the flowing state to be injected. At this time, if the drawing is shallow, the painting sheet may be formed by the resin pressure of the resin in the flowing state to be filled into the mold at the same time as the resin injection without preforming. Further, even when the painting sheet is formed by the resin pressure, the painting sheet may utilize the heat of the injection resin without preheating. In addition, the preforming of the painting sheet is usually performed by using the injection mold also as the vacuum forming mold, but before supplying the painting sheet between the molds, the outside of the mold is used for painting with another vacuum forming mold. Preforming such as vacuum forming the sheet (offline preforming) may be used. However, it is preferable that the preforming is performed by using both the injection molding die and the vacuum molding die in that the painting sheet can be efficiently and accurately laminated. However, in the case where the preformed painting sheets are collectively manufactured in another place in advance, the preforming is preferably in the form of off-line preforming. In the description of the present invention, vacuum forming includes vacuum pressure forming.

Next, an injection molding simultaneous painting method will be described with reference to a conceptual diagram of FIG. Note that, in the embodiment described here, the sheet for simultaneous painting with injection molding is heated and softened between the molds, pre-molded by vacuum molding with an injection mold, and then resin is injected by clamping before clamping. It is a form. This form is more preferable when the drawing sheet is deeply drawn out of the various combinations of the preforming and preheating of the drawing sheet. Note that the sheet for simultaneous injection molding and painting used in the simultaneous injection molding and painting method may be either a single sheet or a continuous band.

First, as shown in FIG. 6A, the injection mold includes a mold Ma having a runner (runner) and a gate (gate) communicating with the injection nozzle, and a suction hole 4 formed in the cavity surface.
A pair of molds Mb having the number 1 and also serving as a sheet preform is used. These molds are made of metal such as iron or ceramics. Both molds Ma and Mb in the mold open state
The sheet S for painting is supplied in between, and the sheet S for painting is supplied to the mold Mb.
Is fixed by pressing it with a sheet clamp 42 having a frame shape in a plan view. At this time, it goes without saying that the base material sheet side with respect to the solvent-resistant layer of the painting sheet is the injection resin side on the right side of the drawing. Next, the painting sheet is appropriately heated and softened by a heater (not shown) inserted between both molds. The heating is, for example, non-contact radiation heating, but may be conduction heating by contact. Then, it is sucked through the suction hole and vacuum formed, and the painting sheet is preformed along the cavity surface of the mold Mb. Next, the heater is retracted from between the two molds, and FIG.
As shown in (B), both molds are clamped, and a cavity formed by both molds is filled with a resin in a flowing state such as a heated and molten state. After the resin is solidified by cooling or the like, the mold is opened and the molded product is taken out. Then, if unnecessary portions of the painting sheet are trimmed appropriately, the painting sheet is laminated on the resin molded product to obtain a painting molded article having a configuration.

Here, in the sectional view of FIG. 7, an example of a molded article using the sheet for simultaneous painting with injection molding obtained by the manufacturing method of the present invention is shown. The picture-formed molded article P in the same figure is formed by simultaneous injection-molded painting on the uneven surface of the resin molded article B, and the sheet S for simultaneous injection-molded painting manufactured by the production method of the present invention.
Is a molded product having a laminated and integrated structure. Although not shown, the sheet for simultaneous injection-molding and painting is laminated on the resin molding so that the solvent-resistant layer of the sheet for simultaneous painting and injection-molding is on the surface side of the molded article for painting.

The resin of the resin molded product B to be laminated on the sheet for simultaneous painting with injection molding obtained by the production method of the present invention, that is, the resin to be injection-molded is not particularly limited, and is generally known. Good with resin. What is necessary is just to select according to the required physical properties of a product, cost, etc. If it is a thermoplastic resin, it may be an ABS (acrylonitrile-butadiene-styrene copolymer) resin, a styrene resin, an acrylic resin, a vinyl chloride resin, a polycarbonate resin, a polyolefin resin, or the like. In addition, as the polyolefin resin,
For example, polyethylene, polypropylene, polybutene,
Polymethylpentene, ethylene-propylene copolymer,
One or a mixture of two or more of ethylene-propylene-butene copolymer and olefin-based thermoplastic elastomer is used. It is also possible to add ethylene propylene rubber to these polyolefin resins in order to improve the adhesion to the sheet for simultaneous painting with injection molding. Ethylene propylene rubber is a rubber (EPR) made of an ethylene-propylene copolymer, and is an amorphous random copolymer. In addition to the pure ethylene-propylene copolymer, an ethylene-propylene-diene terpolymer (EPDM) can be used as the ethylene-propylene rubber. Ethylene propylene rubber is preferably added in the range of 1 to 40 parts by mass with respect to 100 parts by mass of the polyolefin-based resin from the viewpoint of improving adhesion and maintaining rigidity. In addition, when the injection molding resin is a curable resin, a two-component curable resin, for example,
Uncured resin liquids such as urethane resins, unsaturated polyester resins, and epoxy resins. The thermoplastic resin is melted by heating and injected in a fluid state, and the curable resin (the uncured product) is injected in a flowing state at room temperature or appropriately heated. In addition,
As the injection molding resin, when a backing base material layer made of a polyolefin resin is provided on the back surface of the sheet for simultaneous painting with injection molding, the adhesion to the polyolefin resin is good. Resins are preferred.

As the injection molding resin, a resin colored by adding a coloring agent may be used as appropriate according to the intended use.
As the colorant, a known colorant as described in the decorative layer can be used. In addition, the injection molding resin may contain, as necessary, various known additives such as silica, alumina, calcium carbonate, inorganic powders such as aluminum hydroxide, fillers such as glass fibers, stabilizers, and lubricants. .

[Others] In the present invention, the term "painted" refers to a pattern that is not visible, a conductive layer, It also includes providing a functional layer such as a magnetic layer.
Known patterns such as decorative layers formed by printing or the like as visible patterns, examples of invisible patterns are patterns printed with a fluorescent ink that is transparent to visible light and emits fluorescence by ultraviolet irradiation, A bar code or the like printed with an infrared absorbing ink is used.

[0046]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples.

Example 1 Using a transfer sheet T (and a base sheet 1) having a structure as shown in FIG. 3A, a sheet S for simultaneous painting with injection molding having a structure as shown in FIG. It was manufactured in the same manner.

A biaxially stretched polyethylene terephthalate film having a thickness of 26 μm is used as a support sheet 3, and a transparent transfer layer 4 is formed on one side of the support sheet 3, in order, a release layer having a thickness of 2 μm made of an acrylic resin containing polymethyl methacrylate as a main component. 6. The solvent-resistant layer 2 made of a specific material and the primer layer 8 having a thickness of 4 μm made of a mixed resin of a 1: 1 mass ratio of an acrylic resin and a vinyl chloride-vinyl acetate copolymer are entirely coated by gravure printing. And a transfer sheet T was prepared. The solvent-resistant layer 2 is made of an acrylic resin base material 10
30 parts by mass of alumina powder having an average particle size of 2.5 μm was added to 100 parts by mass of a two-part curable acrylic resin obtained by adding 12 parts by mass of a silane coupling agent as a curing agent to 0 parts by mass. Was formed with an ink to which an appropriate amount of an organic solvent was added so as to have a thickness of 4 μm when dried.

Next, a one-to-one ratio of an acrylic resin and a vinyl chloride-vinyl acetate copolymer was applied to a base sheet 1 made of a transparent methyl methacrylate-butyl methacrylate copolymer acrylic resin sheet having a thickness of 125 μm. After forming a 3 μm-thick back surface adhesive layer 9 made of a resin having a mass ratio, the transfer layer 4 is transferred from the transfer sheet T by a normal roller transfer method, and the transfer layer 4 is transferred onto the base sheet 1. 3B, the primer layer 8, the solvent-resistant layer 2 and the release layer 6 were simultaneously laminated from the substrate sheet side to obtain a sheet S for simultaneous painting with injection molding having a structure as shown in FIG. 3B.

Next, the above-mentioned sheet for simultaneous painting with injection molding is
Using an ABS resin as an injection molding resin, a molded article P having a configuration in which a sheet S for simultaneous simultaneous injection molding is laminated on an uneven surface of a resin molded article B as shown in FIG. Prototype made. In addition, the simultaneous painting by injection molding was performed by using a female mold for injection molding as a vacuum molding die, supplying a painting sheet between the molds, softening by heating, and preforming by vacuum molding.

Example 2 Using a transfer sheet T (and a base sheet 1) having a structure as shown in FIG. 4A, a sheet S for simultaneous painting with injection molding having a structure as shown in FIG. It was manufactured.

First, a biaxially stretched polyethylene terephthalate film having a thickness of 26 μm was used as a material sheet 3A, and a release layer (concavo-convex pattern forming layer) 3B for forming concavities and convexities of a wood channel groove pattern was formed on one surface of the material sheet 3A. A support sheet 3 was prepared by gravure printing an ink composed of a curable polyester. Next, a release layer 6 having a thickness of 2 μm made of an acrylic resin containing polymethyl methacrylate as a main component, a solvent-resistant layer 2 made of a specific material, an acrylic A decorative pattern 7 of a woodgrain pattern made of a colored ink obtained by adding a resin and a vinyl chloride-vinyl acetate copolymer in a mass ratio of 1: 1 to a resin, and a coloring agent containing carbon black as a main component, and an acrylic resin. The transfer sheet T was prepared by forming each layer of the primer layer 8 having a thickness of 4 μm made of a resin mixed with a vinyl chloride-vinyl acetate copolymer at a mass ratio of 1: 1 by gravure printing. Note that the solvent-resistant layer 2 was made of a main material 100 of an acrylic resin as in Example 1.
1 part by mass of silane coupling agent as curing agent
Alumina powder having an average particle size of 2.5 μm was further added to 100 parts by mass of the two-part curable acrylic resin added by 2 parts by mass.
0 parts by mass was added thereto, and an ink containing an appropriate amount of an organic solvent was formed so as to have a dry film thickness of 4 μm.

Next, a one-to-one ratio of an acrylic resin to a vinyl chloride-vinyl acetate copolymer was applied to a base sheet 1 made of a transparent methyl methacrylate-butyl methacrylate copolymer acrylic resin sheet having a thickness of 125 μm. After forming a 3 μm-thick back surface adhesive layer 9 made of a resin having a mass ratio, the transfer layer 4 is transferred from the transfer sheet T by a normal roller transfer method, and the transfer layer 4 is transferred onto the base sheet 1. As shown in FIG. 4, a primer layer 8, a decorative layer 7, a solvent-resistant layer 2, and a release layer 6 are simultaneously laminated from the substrate sheet side.
A sheet S for simultaneous injection-molding painting having a channel-shaped concave portion on the surface having the structure as shown in (B) was obtained.

Next, the sheet for simultaneous painting with injection molding produced as described above was laminated on the surface of the ABS resin molded product by the same simultaneous painting method for injection molding as in Example 1 to produce a prototype with painting. .

[Embodiment 3] Using the transfer sheet T (and the base sheet 1) having the structure shown in FIG. 5A, a sheet S for simultaneous painting with injection molding having the structure shown in FIG. It was manufactured. In Example 1, on the back side of the base material sheet 1,
After laminating a 100 μm-thick backing substrate layer 5 using an olefin-based thermoplastic elastomer made of acrylic-modified polypropylene by a melt extrusion coating method, the same transfer sheet T as in Example 1 was used. A primer layer 8, a solvent-resistant layer 2, and a release layer 6 were simultaneously laminated on the front side as the transfer layer 4 from the side of the base sheet 1, to produce a sheet S for simultaneous injection molding and painting as shown in FIG. 5B. The formation of the back adhesive layer provided in Example 1 was omitted. Then, the injection molding simultaneous painting method is the same as in Example 1, except that a polypropylene resin is used instead of the ABS resin as the injection molding resin, and the injection molding simultaneous painting sheet is laminated on the surface of the resin molded product made of the polyolefin resin. A prototype with a picture was produced. In addition, the polypropylene resin of the injection molding resin is such that 10% by mass of ethylene-propylene rubber is added to polypropylene and 20% by mass of talc powder is used.
The added resin was used.

[Comparative Example 1] The same backing adhesive layer 9 as in Example 1 was formed on one side of the base sheet 1 used in Example 1, but the transfer layer 4 was not formed (that is, solvent resistance). A sheet for simultaneous painting with injection molding having a structure having no layers) was produced. Then, using this sheet for simultaneous painting with injection molding,
In the same manner as in Example 1, a molded article with a picture was prototyped.

[Evaluation of Performance] The molded articles with pictures obtained in Examples and Comparative Examples were evaluated for solvent resistance and scratch resistance.

(1) Solvent resistance: The surface of the molded article with pictures was treated with gauze impregnated with methyl ethyl ketone at 9.8 N (1 kN).
After rubbing a plurality of times with the load of gf), the presence or absence of surface abnormality was visually observed and evaluated. As a result, in the painted product of Comparative Example 1, whitening occurred on the surface in three reciprocations, but in each of the painted products of Examples 1 to 3, whitening occurred on the surface only after 20 reciprocations. The improvement of the solvent resistance was confirmed, and the solvent resistance was good.

(2) Scratch resistance: The surface of the molded article was painted with steel wool (trade name "Bonstar", product number: 0000, manufactured by Nippon Steel Wool Co., Ltd.) at 9.8 N (1 kgf).
After rubbing a plurality of times with the above load, the presence or absence of surface abnormalities was visually observed and evaluated. As a result, in the molded article with a picture of Comparative Example 1, scratches were recognized on the surface in three reciprocations, but Examples 1 to 3 were used.
In each of the picture-formed molded articles of Example 3, scratches were observed on the surface only after 50 reciprocations, and an improvement in the scratch resistance was confirmed, and the scratch resistance was good.

[0060]

(1) According to the method for producing a sheet for simultaneous painting with injection molding of the present invention, not only solvent resistance as well as moldability and coating feeling can be obtained, but also scratch resistance can be obtained. In addition, there is no damage to the base sheet such as the base sheet being dissolved by the organic solvent when the solvent-resistant layer is formed. (2) In addition, if a backing base layer made of polyolefin resin is provided on the back side of the base sheet, it is a sheet for simultaneous painting with injection molding that has good adhesion to resin molded products of polyolefin resin which is inexpensive but difficult to adhere to. Is obtained. In addition, the total thickness required for the sheet for simultaneous painting with injection molding is shared with the backing base layer made of inexpensive polyolefin resin in addition to the base sheet made of expensive acrylic resin. Can be manufactured.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram illustrating one embodiment of a production method of the present invention, and a cross-sectional view illustrating an example of a sheet for simultaneous painting with injection molding obtained.

FIG. 2 is a conceptual diagram illustrating another embodiment of the manufacturing method of the present invention, and a cross-sectional view illustrating an example of a sheet for simultaneous painting with injection molding obtained.

FIG. 3 is a cross-sectional view showing another example of a transfer sheet used in the present invention and a sheet for simultaneous painting with injection molding obtained.

FIG. 4 is a cross-sectional view showing another example of a transfer sheet used in the present invention and a sheet for simultaneous painting with injection molding obtained.

FIG. 5 is a cross-sectional view showing another example of a transfer sheet used in the present invention and a sheet for simultaneous painting with injection molding obtained.

FIG. 6 is a conceptual diagram illustrating an example of a simultaneous painting method for injection molding.

FIG. 7 is a cross-sectional view illustrating an example of a molded article with pictures.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 base sheet 2 solvent-resistant layer 3 support sheet 3A material sheet 3B release layer (concavo-convex pattern forming layer) 4 transfer layer 5 backing base layer 6 release layer 7 decorative layer 8 primer layer 9 back adhesive layer 41 Suction hole 42 Sheet clamp Ma Injection molding die (male type) Mb Injection molding die (female type) B Resin molded product P Painted molded product S Sheet for simultaneous injection molded painting T Transfer sheet

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B44C 1/165 B44C 1/165 K // B29L 9:00 B29L 9:00 F term (reference) 3B005 EB03 FA04 FB64 4F100 AH06B AK03C AK15 AK22 AK25A AK25B AL01 AL05 BA02 BA03 BA07 BA10B BA10C CA02B EC042 JB07B JB12B JB16A JK14 4F206 AA13 AD05 AD09 AD20 AG03 JA07 JB12 JB19 JF05

Claims (2)

[Claims] 1. A solvent-resistant layer made of a cured product of a two-part curable acrylic resin obtained by curing an acrylic resin with a silane coupling agent is laminated on the surface side of a base sheet made of a thermoplastic acrylic resin by transfer. A method for manufacturing a sheet for simultaneous painting with injection molding. 2. The method for producing a sheet for simultaneous painting with injection molding according to claim 1, wherein a backing substrate layer made of a polyolefin resin is laminated on the back side of the substrate sheet before or after laminating the solvent-resistant layer. .