JPH06286071A - Manufacture of laminating sheet and manufacture of laminated molded form - Google Patents

Abstract

PURPOSE:To obtain a laminated molded form having soft touching feeling by using a laminated sheet having a soft touching layer to be formed of thermoplastic resin composition containing thermoplastic resin having a functional group, a crosslinker having a functional group capable of being reacted with the group of the resin and elastic fine particles having functional group capable of being reacted with the group of the crosslinker. CONSTITUTION:A laminated sheet 1 has a base material sheet made of thermoplastic resin and a soft touching layer laminated and integrated with the sheet. The touching layer is formed of thermoplastic resin composition containing thermoplastic resin having a functional group, a crosslinker having a functional group capable of being reacted with the group of the resin, and elastic fine particles having a functional group capable of being reacted with the group of the crosslinker. The sheet 1 is ductility-brought into close contact with a surface of a mold 4, molding resin is introduced into the mold 4, and integrated with the sheet 1 thereby to obtain a laminated molded form.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a laminating sheet used for producing molded articles used for housings of office automation equipment and home electric appliances, stationery, etc., and laminating using the laminating sheet. More specifically, it relates to a method for producing a molded article, and more specifically, a method for producing a laminating sheet having a soft touch layer used for producing a laminated molded article having a coating layer having a soft touch feeling (suede tone), and the lamination. The present invention relates to a method for manufacturing a molded product.

[0002]

2. Description of the Related Art In order to give a suede feel (soft touch feel) to the surface of a molded product such as a plastic molded product or a metal molded product, generally, a suede tone (soft touch) is provided.
Paints have been used. However, when forming a suede-like film using a paint, it is necessary to adjust the viscosity and the concentration of the paint, which complicates the work. A paint using an organic solvent needs a booth to dry the solvent, which causes pollution of the work environment and safety and health problems.

In order to solve these problems, a sheet-like suede-like coating material has been proposed as an alternative to paint.
For example, in Japanese Patent Laid-Open No. 2-41243, a suede tone obtained by applying a matte paint obtained by adding a bead pigment to a vehicle of an ionizing radiation curable resin on a base film having good moldability and curing the same. Sheets are proposed.

[0004]

However, since the above-mentioned conventional sheet is formed by providing a resin layer cross-linked by an electron beam on a base material film of ABS resin, polypropylene or the like, the spreadability of the entire sheet is improved. For example, when a molded product having irregularities or a curved surface is covered with a sheet, it is difficult to apply the film while stretching it, and at the same time, it has a drawback that it lacks elasticity. Further, since the above bead pigment has a spherical shape, it is difficult to give a sufficient suede feeling.

By the way, the inventors of the present invention have already improved the above-mentioned problems, and it is possible to attach a molded product having unevenness or a curved surface while stretching, and a soft touch feeling (suede-like) on the surface of the molded product. The present inventors have obtained knowledge on a lamination sheet capable of imparting a sheet and a method for manufacturing a laminated molded article using the sheet. In this laminating sheet, the sheet is formed from a resin composition containing elastic fine particles for imparting a soft touch feeling, and the unevenness formed on the sheet surface by blending the elastic fine particles gives a soft touch feeling to the sheet. Granted.

However, the soft touch feeling cannot be said to be sufficient in the unevenness or curved surface portion of the surface of the molded product where the sheet is greatly stretched, and when the amount of the elastic fine particles is large, the sheet becomes hard and the The spreadability was inferior and there was a risk of cracking the sheet during spreading.

The present invention has solved the above-mentioned problems, and it is an object of the present invention to allow a molded product having unevenness or a curved surface to be attached while being stretched, and in particular, the unevenness in which the sheet is stretched. It is possible to form a suede-like coating that does not deteriorate the appearance and soft touch feeling by stretching even on curved parts and curved parts, etc., and a method for manufacturing a laminated sheet, and a laminated molded product using the sheet. To provide a method.

Another object of the present invention is to increase the interfacial strength between the elastic fine particles and the thermoplastic resin which is the matrix of the sheet, so that even the surface unevenness or curved surface portion of the molded product, which greatly stretches the sheet, is sufficiently softened. A method for producing a laminating sheet that can impart a touch feeling, does not significantly reduce the scratch resistance of the surface of the molded article, and suppresses the occurrence of cracks in the sheet, and a method for producing a laminated molded article using the sheet To provide.

[0009]

The method for producing a laminating sheet according to the present invention comprises a thermoplastic resin having a functional group, and a crosslinking agent having a functional group capable of reacting with the functional group of the thermoplastic resin.
A step of forming a resin layer by applying a thermoplastic resin composition containing elastic fine particles having a functional group capable of reacting with the functional group of the crosslinking agent onto a thermoplastic resin base sheet, and the resin. By heating the base material sheet on which the layer is formed, the thermoplastic resin and the elastic fine particles are reacted via the cross-linking agent to form a soft touch layer made of the thermoplastic resin composition, The above object is achieved thereby.

The method for producing a laminated molded article of the present invention comprises the steps of spreading and adhering the laminating sheet obtained by the above method to the mold surface of a mold, and introducing a molding resin into the mold. The step of integrating with a laminating sheet is included, whereby the above object is achieved.

The expression of soft touch feeling in the present invention is
It is speculated that a smooth feel is generated due to the fine irregularities on the sheet surface. This effect is also useful for controlling the reflectance of light on the surface by forming fine irregularities, that is, for gloss control. Therefore, the soft touch layer formed on the laminating sheet means a resin layer having such a soft touch feeling on the surface and having a predetermined thickness. The fine irregularities are generated by mixing the elastic fine particles in the sheet as described later, and the dimension of the fine irregularities is usually 1 to 50 μm.

(Soft Touch Layer) The elastic fine particles contained in the thermoplastic resin composition have a functional group and have a property of elastically recovering when released after being pressurized until the shape is deformed. It is a thing.

As the resin forming the elastic fine particles,
For example, PMMA (polymethylmethacrylate), SBR
(Styrene-butadiene copolymer), polyurethane, acrylic-urethane copolymer and the like. These elastic fine particles include spherical fine particles synthesized by methods such as emulsion polymerization and suspension polymerization, and polygonal fine particles obtained by crushing cast-cured particles. The functional group of the elastic fine particles is
Any compound capable of reacting with the functional group of the crosslinking agent used in the present invention may be used, and examples thereof include an epoxide group, an amino group, a carboxyl group, a hydroxyl group and an amino group.

In order to obtain elastic fine particles having such a functional group, there are mainly the following methods.

When the elastic fine particles are formed of a polymer,
Alternatively, a method of forming a polymer and then copolymerizing the polymer with a reactive comonomer having a target functional group.

In this method, a monomer, an oligomer, or a prepolymer used for the polymerization reaction of the polymer is copolymerized with a reactive comonomer having a desired functional group, and the functional group is formed into elastic fine particles. It is a method of introducing into a polymer.

The functional groups that can be introduced by this method include
Examples thereof include epoxide group, amino group, carboxyl group, hydroxyl group and amino group. For example, reactive comonomers used to introduce hydroxyl groups include allyl alcohol, 2
-Hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, monoallyl ether of polyhydric alcohol and the like are mentioned, and as the reactive comonomer used for introducing the carboxyl group, acrylic acid, methacrylic acid,
Examples include maleic acid.

A method in which elastic fine particles are formed by polymerizing a polymer and the polymer is chemically treated to introduce a target functional group.

This method is based on the stability of monomers, copolymerizability,
This is a method of introducing a desired functional group by chemical treatment of the obtained polymer after copolymerizing a certain kind of reactive comonomer in some cases in consideration of economical efficiency.

For example, in order to introduce a hydroxyl group, it can be introduced by hydrolysis of a polymer having an ester bond in the side chain or esterification reaction of a polymer having a carboxyl group in the side chain with a monofunctional epoxy compound. .

A functional group can be introduced into the terminal of the polymer main chain by using a part of the polymer material used for the polymerization reaction in excess.

It is preferable to add 50 to 200 parts by weight of the elastic fine particles having a maximum particle size distribution in the range of 1 to 300 μm to 100 parts by weight of the thermoplastic resin. If the particle size is less than 1 μm, the obtained sheet does not have a sufficient suede feeling (soft touch feeling) and the particle size is 30
When it exceeds 0 μm, cracks are likely to occur on the surface of the sheet during stretching. If the added amount is less than 50 parts by weight, a sufficient suede feeling (soft touch feeling) cannot be obtained, and if the added amount is more than 200 parts by weight, cracks are likely to occur on the surface of the sheet during stretching. The elastic fine particles are not limited to one type, and two or more types may be used in combination with an inorganic filler or the like.

The thermoplastic resin contained in the thermoplastic resin composition for forming the soft touch layer includes acrylic resin, silicone resin, urethane resin, polyether, polyester, vinyl acetate resin, polyvinyl alcohol, polyvinyl butyral. Etc.

This thermoplastic resin is produced by the same method as that of the elastic fine particles described above, that is, by copolymerizing with a certain reactive monomer in the polymerization reaction of the polymer, or by using one of the monomers, oligomers, etc. used in the polymerization reaction. By using an excess of part, a functional group can be introduced into the polymer chain or terminal of the thermoplastic resin.

In addition, since the unevenness of the soft touch layer on the surface of the sheet is effectively exhibited by stretching the laminating sheet at room temperature or by softening by heating, the melt viscosity of the thermoplastic resin composition during sheet forming is It is preferably from 20 to 500 poise. However, this range is somewhat changed depending on the addition amount of the elastic fine particles and the elasticity thereof.

Next, the urethane resin preferably used for the soft touch layer as the thermoplastic resin will be described in detail below.

The urethane resin has a glass transition point (T) in order to impart a soft touch feeling and scratch resistance of the laminating sheet.
It is preferable that g) is in the range of -50 ° C to 20 ° C. When a urethane resin having a glass transition point of less than −50 ° C. is used and a urethane resin having a glass transition point of more than 20 ° C. is used, the soft touch feeling becomes poor.

The urethane resin is classified into a straight-chain type (high molecular weight type) and a cross-linking type (reaction film forming type), and both can be used.

When a linear type urethane resin is used, a method of forming a laminating sheet by directly forming a film of the thermoplastic resin composition by a casting method can be applied.

Such urethane resin is usually obtained by reacting a diisocyanate, a diol and a chain extender. Examples of the diisocyanate include tolylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, tolidine diisocyanate, p-phenylene diisocyanate, xylylene diisocyanate, bis (isocyanatomethyl) cyclohexane, dicyclohexylmethane diisocyanate, lysine diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, tetra Examples thereof include methylxylylene diisocyanate and trimetol hexamethylene diisocyanate. Examples of the diol include polyester diols (condensed polyester diols, lactone polyester diols, polycarbonate diols, etc.), polyether diols, etc. , Ethylene glycol , 1,4-butanediol, and hydroquinone diethylcarbamoyl roll ether.

The urethane resin made of these materials includes
The functional group can be introduced into the polymer chain in the same manner as the elastic fine particles described above under the condition that the functional group of the reactive comonomer does not react with the unreacted monomer or oligomer. Further, in order to introduce a functional group into the polymer terminal of the polymerized urethane resin, or by adjusting the compounding amount of isocyanate, diol, glycol or the like, an isocyanate group or a hydroxyl group is introduced into the polymer terminal. be able to.

The linear type polyurethane can be obtained by previously polymerizing the above materials in a solution to obtain a urethane resin (a catalyst such as dibutyltin dilaurate may be added to accelerate the reaction). In this case, the urethane resin preferably has a weight average molecular weight in the range of 20,000 to 3,000,000. If the weight average molecular weight is less than 20,000, the sheet is likely to be cracked during sheet spreading. When the weight average molecular weight exceeds 3,000,000, it becomes difficult to dissolve the resin in the solvent, and for example, when a sheet is prepared by solvent casting, the solvent viscosity becomes high, and therefore the resin can be cast only at a low concentration, and therefore, the thick film It would be very expensive to make a sheet. When a cross-linking type urethane resin is used, the aforementioned low molecular weight materials, oligomers obtained by polymerizing them, and / or 3
It is possible to prepare a laminated sheet by casting a resin composition composed of an isocyanate having a functionality or higher on a sheet and then reacting it by heating.

Also in the case of using a linear polyurethane, as in the case of polymerizing at the time of casting, a low molecular weight material or a polymerized polymer material thereof is used, and at least a trifunctional or higher functional isocyanate is added. In addition, it is also possible to crosslink with heat during film formation to further increase the molecular weight. These at least trifunctional or higher functional isocyanates are added within a range in which the sheet can be spread (curved surface followability). Examples of such an isocyanate include an isocyanurate body of hexamethylene diisocyanate and a trimethylolpropane adduct. By using the urethane resin partially cross-linked in this way, it is possible to improve the solvent resistance of the laminating sheet. Further, a melamine cross-linking agent may be used in addition to the isocyanate. The amount of each of these materials added is within the appropriate range of the melt viscosity during sheet molding.

When an acrylic resin is used as the thermoplastic resin, in addition to the same material design as described for the urethane resin, the acrylic resin may be
It is also possible to add a material having a reactive double bond such as a vinyl group and a photoinitiator, adjust the melt viscosity, and further irradiate with light to cure the surface. When the thermoplastic resin composition contains a plasticizer, a resin other than those described above, for example, one having a high molecular weight or one having advanced crosslinking can be used.

Further, the cross-linking agent contained in these compositions is added to the extent that spreading of the sheet is permitted, and cross-links during film formation of the sheet.

That is, regarding the cross-linking agent, a monomer or oligomer chain extender used in the polymerization reaction of a low molecular weight material or a thermoplastic resin is described in the above range as long as the sheet can be spread (curved surface followability). The thermoplastic resin and the elastic fine particles are simultaneously added at the stage of mixing, and the resulting thermoplastic resin composition is applied onto a thermoplastic resin base sheet to form a resin layer, and then heat-dried during heating and drying. Is to react with the thermoplastic resin and the elastic fine particles.

The functional groups contained in the thermoplastic resin and the elastic fine particles take into consideration the reactivity with the functional group contained in the crosslinking agent, and the crosslinking reaction between the polymers constituting the thermoplastic resin. Not only this, but also the functional groups of the elastic fine particles are reacted.

For example, when a urethane resin is used as the thermoplastic resin, since it has a hydroxyl group at least at the terminal, elastic fine particles having a hydroxyl group as a functional group are used, and the hydroxyl group of the urethane resin and the hydroxyl group of the elastic fine particles are used. A crosslinking agent having an isocyanate group as a functional group capable of reacting with can be used. In this case, as the cross-linking agent, for example, diisocyanate and / or triisocyanate used in the above-mentioned polymerization reaction is 0.1 to 20% by weight, preferably 0.5 to 0.5% by weight with respect to the urethane resin in consideration of sheet spreadability. ~ 5 wt% can be added.

A thermoplastic resin composition containing a thermoplastic resin, elastic fine particles and a cross-linking agent is applied onto a thermoplastic resin base sheet to form a resin layer, and by heating this, a soft touch layer is formed. To be done. By this heating,
The thermoplastic resin in the resin layer reacts with the elastic fine particles, and the elastic fine particles react with the crosslinking agent. In this way, by partially crosslinking the resin, it becomes possible not only to increase the molecular weight of the thermoplastic resin, but also to improve the interfacial strength between the thermoplastic resin and the elastic fine particles, making it difficult for the elastic fine particles to come off from the sheet. At the same time, performance such as solvent resistance of the soft touch sheet can be improved.

The thermoplastic resin composition used in the present invention may further contain materials such as pigments, colorants such as dyes, and antioxidants, if necessary. As the colorant, pigments and dyes used in paints can be used. In pigments, titanium oxide,
Examples include iron oxide, carbon black, cyanine pigments, quinacridone pigments and the like. Examples of dyes include azo dyes, anthraquinone dyes, indigoid dyes, and stilbenzene dyes. In addition, aluminum flakes, metal powder such as nickel powder, gold powder, and silver powder may be used as the colorant. It is preferable that these materials are fine particles. When a coloring agent having a high hiding property is used, the addition amount of these is 2 to 100 parts by weight of the solid content of the thermoplastic resin.
A range of 400 parts by weight is preferred. However, when these colorants are added, the soft touch feeling imparted by the natural fine particles or the like may be different, so that the appropriate amount of elastic fine particles may change in the system in which the colorant is added.

Various functionalizing materials may be added to impart various functions to the above-mentioned laminating sheet. Examples of the various functional imparting materials include known conductive materials, anti-condensation agents, photochromic compounds, rust preventives, and the like.

(Preparation of Laminating Sheet) A thermoplastic resin composition obtained by kneading the above materials is applied onto a thermoplastic resin base sheet to form a resin layer, and the resin layer is heated. As a result, the thermoplastic resin contained in the resin composition and the elastic fine particles are reacted with each other through the crosslinking agent to form the soft touch layer. The soft touch layer (base layer) is laminated and integrated on a thermoplastic resin base sheet to form a laminating sheet.

Examples of the method for manufacturing the laminating sheet include a casting film forming method and an extrusion molding method.

The laminating sheet has the following forms, for example.

A sheet having a base layer (soft touch layer) and a thermoplastic resin base sheet laminated on the back surface of the base layer.

This thermoplastic resin base sheet further improves the handleability of the sheet, and when the sheet is used for injection molding, it improves the adhesion between the laminating sheet and the injection molding resin. Alternatively, a plurality of layers may be provided to reinforce the resin for injection molding so as to withstand the shear stress.

Since the laminating sheet is stretched as necessary and attached to the adherend, the substrate sheet (and the primer layer) is composed of a thermoplastic resin film having ductility at room temperature or at least under heating. Preferably.

Examples of the resin used for the thermoplastic resin base sheet are polystyrene, acrylic polymer, polycarbonate, polyvinyl chloride, polyethylene, polypropylene, ABS copolymer (acrylonitrile-butadiene-styrene copolymer). In addition to modified polyphenylene oxide, polyphenylene sulfide, polyetherimide, polyetheretherketone, etc., ionomers, thermoplastic elastomers, etc. can be mentioned. Moreover, you may use what laminated | stacked the foam layer to these base material sheets.

A sheet having an adhesive layer (primer layer) laminated on the outer surface of the base sheet of the laminating sheet obtained above or between the base layer and the base sheet.

As the adhesive used in the adhesive layer, a pressure sensitive adhesive, a hot melt adhesive, and a post-curable adhesive are preferably used. Compositions of these adhesives may be used. A plurality of different types of adhesive layers may be sequentially laminated. The primer layer is used depending on the properties of the resin to be laminated, and for example, chlorinated polyolefin such as chlorinated polypropylene can be used.

Examples of the pressure-sensitive adhesive include rubber-based, acrylic-based, silicone-based and other pressure-sensitive adhesives. Examples of hot melt adhesives include ethylene-vinyl acetate copolymer (EVA) adhesives and styrene-isoprene-styrene block copolymer (SIS) adhesives. Post-curing adhesives include, for example, microcapsule curing adhesives, and examples of the material thereof include uncrosslinked unsaturated polyester adhesives and uncrosslinked acrylic adhesives.

A sheet having the sheet obtained in the above or above and a protective layer laminated on the surface of the sheet.

The protective layer is laminated in order to impart shape retention during storage and use of the sheet and surface protection after attachment.

The sheet produced according to the present invention is stretched as necessary and attached to an adherend. Therefore, the protective layer is a film having a malleability at room temperature or at least under heating (for example, a thermoplastic resin film or a rubber film). Is preferred.

Examples of the above-mentioned thermoplastic resin include polyvinyl chloride, polyurethane, acrylic resin, polyester, ethylene-vinyl acetate copolymer, polyethylene,
Examples include polypropylene. Examples of the rubber film include natural rubber, styrene-butadiene rubber, nitrile-butadiene rubber, isoprene rubber, butadiene rubber, chloroprene rubber, urethane rubber, silicone rubber, acrylic rubber and the like. Compositions with these thermoplastics and rubbers can also be used, or
Both films may be laminated.

These protective layers may be used as protective layers until the sheet is attached to the surface of the adherend or before the adherend is used. By embossing or patterning the surface of the protective layer, the surface shape (appearance) of the sheet can be changed after the protective layer is peeled off.

The thickness of the laminating sheet obtained in the above-mentioned items varies depending on the part to be attached or the surface condition, but it is 20-
About 1,000 μm is preferable. The thickness of the other layers attached to the base sheet is preferably 10 to 500 μm, and particularly the thickness of the adhesive layer (primer layer) is 2 to 100 μm.
Is preferred.

(Manufacturing Method of Laminated Molded Article) The method of manufacturing a laminated molded article according to the present invention comprises
After the soft touch layer is brought into close contact with the mold surface so as to come into contact with the mold surface, resin is introduced into the mold to perform batch molding. For example, injection molding, stamping molding, press molding, sheet molding. Etc.

Typically, the laminated sheet is brought into close contact with the inner surface of the cavity provided in the female mold by pneumatic molding, that is, vacuum and / or pneumatic molding, and then a resin is injected to produce a laminated molded article. .

A method of manufacturing a laminated molded article will be described below with reference to the drawings.

FIGS. 1 to 4 show an example of an injection molding apparatus used in a method for manufacturing a laminated molded article. This apparatus has a female mold 4 having a cavity 5 and a male mold 8 having a convex portion 9. An injection molding machine (not shown) for supplying resin into the cavity 5 formed by the female mold 4 and the male mold 8; and a heating platen 2 for heating the sheet 1. The heating platen 2 is configured to be movable toward and away from the cavity 5 of the female die 4, and a driving means (not shown) for driving the heating platen 2 is provided.

As shown in FIGS. 2 and 3, the female mold 4 is
A vent hole 4a which opens to the inner surface of the cavity 5 and a female shape 4
A ventilation port 4b is provided on the upper end surface of the frame portion 7 of FIG. The convex portion 9 of the male mold 8 is provided with a gate 6 for supplying the resin 12 injected from the injection molding machine into the cavity 5. Further, the heating board 2 is provided with a suction port 2a, and the sheet 1 can be sucked on the lower surface thereof.

In order to manufacture a laminated molded product using such an apparatus, first, as shown in FIG.
The sheet 2 is heated by adhering the sheet 2 to the lower surface of the heating platen 2 in a state of being sucked from. Here, the sheet 2 is the heating plate 2
It will be heated by the heat from to increase the malleability. In this state, the heating platen 2 is placed on the cavity 5 of the female die 4 as shown in FIG. 2, so that the end portion of the sheet 2 is brought into contact with the upper end surface of the frame portion 7 of the female die 4. At this time, it is preferable that the end portion of the sheet 1 is fixed to the upper end surface of the female die 4 by sucking through the suction port 4b provided on the upper end surface of the frame portion 7.

Next, as shown in FIG. 3, the gas in the cavity is sucked from the suction port 4a in the female mold 4 and the air is blown from the ventilation port 2a provided in the heating platen 2 so that the inside of the cavity 5 is closed. With the pressure reduced, the sheet 1 is moved to the female mold 4
It is brought into close contact with the inner surface of the cavity 4. Next, the heating platen 2 is separated from the sheet 1 and moved to the side of the female mold 4. When the heating platen 2 is separated from the sheet 1, the gas is blown out from the ventilation port 2a provided in the heating platen 2, so that the sheet 1
May be easily separated.

Next, as shown in FIG. 4, the male mold 8 is replaced by the female mold 4.
Then, the resin 12 is injected into the cavity 5 formed by the molds 4 and 8 from the injection molding machine (not shown) through the gate 6 to obtain a laminated molded product. The opening of the suction hole 4a provided in the female die 4 is preferably provided in the unobtrusive portion of the molded product that has come out.

As the injection molding resin, any material can be used as long as it is a material conventionally used for injection molding. For example, polystyrene, acrylic polymer, polycarbonate, polyvinyl chloride, polyethylene, polypropylene, ABS (acrylonitrile-butadiene-styrene copolymer), modified polyphenylene oxide, polyphenylene sulfide, polyetherimide, polyether ether ketone, polyethylene sulfide, liquid crystal Polymer, glass fiber reinforced polyester,
Examples thereof include glass fiber reinforced epoxy, glass fiber reinforced acrylic resin, a mixture of isocyanate and a glycol compound.

For the laminated molded article, an apparatus other than the above is used,
Also, it can be manufactured by a method other than the above, but in any manufacturing method, a sheet is introduced into the mold (preferably, it is introduced in a state of being softened by heating and softening the sheet) to form the mold surface. It is closely adhered, and the resin is introduced into the mold in that state and clamped, or the sheet is introduced into the mold and then clamped, and then the resin is introduced into the mold in that state to manufacture.

[0068]

The laminating sheet of the present invention has a soft touch layer formed of a thermoplastic resin composition containing elastic fine particles, a thermoplastic resin and a cross-linking agent. A laminated molded product having a soft touch feeling on the surface can be easily obtained only by sticking.

When this laminating sheet is used, a film having a uniform appearance is formed even in the production of a laminated molded article having irregularities, because the appearance change and the soft touch feeling are not deteriorated even in the stretched portion of the sheet. It becomes possible.

In particular, in the soft touch layer, it is presumed that the blended elastic fine particles and the thermoplastic resin are bonded by the cross-linking agent, but the interface strength between the elastic fine particles and the thermoplastic resin is large. Therefore, it becomes possible to form a coating that does not cause a change in appearance or a decrease in softness even when the sheet is greatly stretched, such as irregularities or curved surfaces, and the performance such as scratch resistance and heat resistance is improved. Is possible.

[0071]

EXAMPLES The present invention will be described in detail below based on examples.

In the following examples, "part" means "part by weight".
Means

(A) Preparation of Laminating Sheet (Example 1) Thermoplastic resin: urethane resin (manufactured by Nippon Polyurethane Industry Co., Ltd., polycarbonate urethane SH703, containing hydroxyl group) 100 parts Crosslinking agent: manufactured by Nippon Polyurethane Industry Co., Ltd. , Coronate 2
094, bifunctional isocyanate compound)
5 parts Elastic fine particles: Sekisui Chemical Co., Ltd., Techpolymer MBX-
8, average particle size 8 μm, but 70 parts by weight having a hydroxyl group as a functional group) were used.

The above materials were mixed with stirring to obtain a thermoplastic elastomer sheet (Sanbo Resin Co., Ltd.).
(Manufactured, film thickness 400 μm, hereinafter referred to as TPO sheet) so that the coating film thickness is 60 μm, and dried at 80 ° C. for 30 minutes or more to form a soft touch layer to obtain a laminating sheet.

(Example 2) Thermoplastic resin: urethane resin (same as in Example 1) 10
0 part Cross-linking agent: Nippon Polyurethane Industry Co., Ltd., Coronate H
X, trifunctional isocyanate compound) 3
Part Elastic fine particles: Sekisui Kasei Co., Ltd., Techpolymer MBX-
8, average particle size 8 μm, but 70 parts by weight having a hydroxyl group as a functional group) were used.

The above materials were mixed with stirring to obtain a thermoplastic elastomer sheet (Sanbo Resin Co., Ltd.).
(Manufactured, film thickness 400 μm, hereinafter referred to as TPO sheet) so that the coating film thickness is 60 μm, and dried at 80 ° C. for 30 minutes or more to form a soft touch layer to obtain a laminating sheet.

Comparative Example 1 Thermoplastic resin: urethane resin (same as in Example 1) 10
0 part Crosslinking agent: the same as in Example 1 5 parts Elastic fine particles :: Sekisui Kasei Co., Ltd. Techpolymer MBX
-8, average particle size 8 μm, but no functional group) 70 parts were used.

The above materials were mixed with stirring to obtain a thermoplastic elastomer sheet (Sanbo Resin Co., Ltd.).
(Manufactured, film thickness 400 μm, hereinafter referred to as TPO sheet) so that the coating film thickness is 60 μm, and dried at 80 ° C. for 30 minutes or more to form a soft touch layer to obtain a laminating sheet.

(Comparative Example 2) A soft touch paint (Cenosoft II, manufactured by Cashew Co., Ltd.) was applied onto a TPO sheet (same as in Example 1) so that the coating film thickness was 60 μm,
The surface layer was formed by heating and curing at 30 ° C. for 30 minutes to obtain a laminating sheet.

(B) Manufacture of Laminated Articles by Injection Molding The lamination sheets obtained in Examples 1 and 2 and Comparative Examples 1 and 2 were injection-molded.

The shape of the cavity 5 of the used female mold 4 is shown in FIG.
FIG. 6 shows a plan view of the female die 4. The cavity 5 has a semi-spherical protrusion 5a. Dimensions of each member shown in FIGS. 5 and 6 are (mm) as follows.

L1 = 90, L6 = 20, L7 = 60, L8 = 7
0, L9 = 150, L10 = 15, L11 = 15, L12 = 30,
L13 = 50, L14 = 20, R1 = 30, L21 = 10, L22 =
10.

Molding was carried out as follows using the apparatus shown in FIGS. 1 to 4.

The sheet 1 was heated while adsorbed to the lower surface of the heating platen 2 and moved to a position above the cavity 5 of the female die 4 (FIG. 1).

The heating board 2 was placed on the upper surface of the female die 4, the sheet 1 was brought into close contact with the upper end surface of the frame portion 7, and the suction of the heating board 2 was stopped (FIG. 2).

The sheet 1 was suctioned from the ventilation holes 4a provided in the female die 4 and the sheet 1 was brought into close contact with the inner surface of the cavity 5 of the female die 4 by the compressed air from the ventilation holes 2a provided in the heating plate 2 (FIG. 3). .

After the mold was clamped, polypropylene (manufactured by Mitsubishi Petrochemical Co., Ltd., Hypol X-25) was injected into the cavity 5 at 230 ° C. (FIG. 4).

Table 1 shows the results of evaluation of the sheet forming conditions, the appearance of the obtained laminated molded article and the soft touch feeling in each of the examples and comparative examples.

(Evaluation of Soft Touch Feeling) The soft touch feel is evaluated by a sensory test based on the feeling when the following panelists touch the surface of the molded product, and when the total panel score is 55 points or more. It was good.

Panelists: 20 men and women aged 15-40 years
Name Rating point: 3… Feels soft 2… Feels somewhat soft 1… Does not feel soft (Scratch resistance test) For evaluation of scratch resistance, use Taber Scratch Tester manufactured by Toyo Seiki Co., Ltd. Using the sheets of Examples and Comparative Examples, a scratch strength test was carried out on the plane portion of the laminated molded article.

Test conditions A scratch strength test was conducted at a motor rotation speed of 0.5 to 1.0 rpm, and when a grade 4 or higher was satisfied (a slight scratch on the epidermis was visually observed, but it was not noticeable). The load was calculated. The results are shown in Table 1.

[0092]

[Table 1]

In Comparative Example 2, it was attempted to carry out injection molding by the same method as in Example 1, but the elongation of the sheet was insufficient, and cracks were generated in the hemispherical portion of the sheet corresponding to the cavity 5a, which was favorable. It could not be molded.

[0094]

EFFECT OF THE INVENTION Since the laminating sheet obtained by the present invention is excellent in spreadability, it does not cause cracks when molding not only flat articles but also molded articles having irregularities or curved surfaces. It is possible to form a coating having a soft touch feeling (suede tone) on the surface of the molded product.

Therefore, there is an advantage that the problem of the conventional painting space and the environmental problem such as the solvent are eliminated, and the decoration of various plastic moldings such as housings and stationery of office automation equipment, home appliances, etc. can be performed easily and inexpensively. There are advantages.

Further, the laminating sheet has a larger interfacial strength between the elastic fine particles and the thermoplastic resin mixed in the sheet than in the conventional case, so that the appearance change and the softness of the sheet even when the sheet is greatly stretched or curved portions are softened. It is possible to form a film that does not reduce the feeling, scratch resistance,
Performance such as heat resistance can also be improved.

Further, according to the method for manufacturing a laminated molded product of the present invention, there is an advantage that these molded products can be manufactured very easily and at low cost.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a state in which a laminating sheet is adsorbed on a heating plate of an injection molding apparatus preferably used in the method for manufacturing a laminated molded article of the present invention.

2 is a vertical cross-sectional view showing a state in which a laminating sheet is arranged on the upper surface of a female mold of the injection molding apparatus of FIG.

FIG. 3 is a vertical cross-sectional view showing a state in which a lamination sheet is spread and brought into close contact with a cavity mold surface of a female mold of the injection molding apparatus of FIG.

FIG. 4 is a vertical cross-sectional view showing a state where a molding resin is injected into the cavity after the injection molding apparatus of FIG. 1 is clamped.

FIG. 5A is a plan view schematically showing a contour of a cavity shape of an apparatus suitably used in the method for manufacturing a laminated molded article of the present invention. (B) is a side view which shows the outline of a cavity shape. (C) is a side view which shows the outline of a cavity shape.

FIG. 6 is a plan view of a female mold.

[Explanation of symbols]

 1 Laminating Sheet 2 Heating Plate 4 Female Mold 5 Cavity 8 Male Mold 12 Molding Resin

Claims (2)

[Claims] 1. A thermoplastic resin having a functional group, a crosslinking agent having a functional group capable of reacting with the functional group of the thermoplastic resin, and elastic fine particles having a functional group capable of reacting with the functional group of the crosslinking agent. A step of forming a resin layer by applying a thermoplastic resin composition containing, on a thermoplastic resin-made base sheet,
By heating the base material sheet on which the resin layer is formed, the thermoplastic resin and the elastic fine particles react with each other through the cross-linking agent to form a soft touch layer made of the thermoplastic resin composition. A method of manufacturing a laminating sheet including the step of: 2. A laminated molded article including a step of spreading and adhering a laminating sheet to a mold surface of a mold, and a step of introducing a molding resin into the mold to integrate with the laminating sheet. A method for producing a laminated molded article, wherein the laminating sheet is obtained by a method including the following steps: a thermoplastic resin having a functional group, and a functional group of the thermoplastic resin. A thermoplastic resin composition containing a cross-linking agent having a functional group capable of reacting with and a fine elastic particle having a functional group capable of reacting with the functional group of the cross-linking agent is applied onto a thermoplastic resin substrate sheet. To form a resin layer, and by heating the base material sheet on which the resin layer is formed, the thermoplastic resin and the elastic fine particles are caused to react with each other through the crosslinking agent, and the thermoplastic resin Forming a soft touch layer of the composition.