JP4383460B2 - Manufacturing method of decorative molded products - Google Patents

Description

  The present invention relates to a method for producing a resin molded product (decorated molded product) whose surface is decorated using a sheet for simultaneous injection molding.

  Conventionally, a decorative molded product in which decoration such as a pattern is imparted to the surface of an injection molded body has been used for various purposes. As a method for producing a decorative molded product, a method described in Patent Document 1 below is known. In this method, a thermoplastic synthetic resin sheet (decorative sheet) on which characters, designs, etc. are printed is fixed to a female mold for injection molding so that the printed layer is opposite to the female mold, After heat softening, vacuum molding is performed on the cavity surface of the female mold, and the male mold is combined with the female mold, and the fusion resin is formed in the cavity formed by the male and female molds. The decorative molded body can be obtained by press-fitting and integrating the surface layer with the injection molded body by integrating with the molded sheet by the injection molding means.

  In Patent Document 2 below, for example, as a decorative sheet, a substrate sheet made of a thermoplastic resin is provided with a decorative pattern by printing or the like, and a transparent thermoplastic resin sheet (clear sheet) is laminated on this sheet. A method is described in which a laminated sheet is used to form a molding sheet by a vacuum mold, and this is placed in an injection mold to perform injection molding to obtain a decorative molded body. Lamination of the base material sheet and the clear sheet was performed by a heat-sealing method or the like, and when preforming a decorative sheet, the temperature was about 120 ° C. to 160 ° C., and vacuum forming was performed.

Japanese Patent Publication No. 50-19132 Japanese Examined Patent Publication No. 61-17255

  In the conventional method for producing a decorative molded body, there has been a problem that the surface of the decorative sheet becomes a skin-like shape during vacuum forming. When the surface of the decorative sheet becomes a skin-like shape before injection molding, the skin-like pattern of the decorative sheet appears on the surface of the molded product, and the appearance of the molded product becomes poor.

  The present invention was made in order to eliminate the above-mentioned disadvantages of the prior art, and prevents the surface of the decorative sheet from becoming a skin-like surface during vacuum forming, so that no defective molding occurs. It aims at providing the manufacturing method of a molded object.

In the present invention, (1) a base sheet made of polypropylene and a surface sheet made of a transparent acrylic resin and a lubricant in a proportion of 0.1 to 0.5% by mass with respect to the resin are _heated at a temperature T _LAMI . By preparing a decorative sheet laminated by bonding and vacuum forming using the decorative sheet at a temperature T _PRE, it is preformed into a female mold surface shape of an injection mold, and the above preliminary molding With the decorative sheet mounted on the injection mold female mold, the injection mold female mold and male mold are closed, and the resin in fluid state is injected and filled into the cavity formed between the molds. The decorative sheet is manufactured by laminating and adhering the decorative sheet to the surface of the molded article, and the temperature T _{LAMI of the} decorative sheet is thermally bonded. When the temperature T _pRE of the preformed decorative sheet To specify the relationship to _{T LAMI> T PRE,}
And a method of manufacturing the decorative molded article, which comprises a 160 ° C. Ultra to 180 ° C. The _{T LAMI,}
(2) The method for producing a decorative molded product according to (1) above, wherein the surface glossiness (measured value at an incident angle of 60 degrees) in the decorative sheet after vacuum forming is 85 or more, as well as
(3) The method for producing a decorative molded product according to (1) or (2), wherein the total sheet thickness of the decorative sheet is 0.1 to 0.6 mm,
Is a summary.

In the present invention, a base sheet made of polypropylene and a surface sheet made of a transparent acrylic resin and a lubricant in a proportion of 0.1 to 0.5% by mass with respect to the resin are laminated by thermal bonding at a temperature T _LAMI . The decorative sheet is prepared and preformed into a female mold surface shape of an injection mold by performing vacuum forming at a temperature T _PRE using the decorative sheet. With the injection sheet on the injection mold female mold, the injection mold female mold and the male mold are closed, and the resin in the fluid state is injected and filled into the cavity formed between both molds to solidify At the same time, a molded product is obtained, and at the same time, a decorative molded product is manufactured by laminating and bonding the decorative sheet to the surface of the molded product, and the temperature T _LAMI of the decorative _sheet and the decorative The relationship between the temperature T _PRE for sheet pre-forming and T _LAMI > T _PRE When the pre-molding is performed by vacuum forming while heating (softening) the two-layered decorative sheet prepared by thermal bonding, the surface sheet of the decorative sheet is generated. Since no haze-like appearance defects occur, it is possible to prevent a molding defect and obtain a decorative molded product with a good appearance.

  Hereinafter, the present invention will be described in detail with reference to the drawings. As shown in FIG. 1A, the method for producing a decorative molded product of the present invention is a decoration in which a base sheet 2 made of a thermoplastic resin and a surface sheet 3 made of a thermoplastic resin are laminated by thermal bonding. Sheet 1 is used. The base material sheet 2 becomes the side in contact with the injection resin side during the production of the decorative molded product, and the topsheet 3 is located on the outermost surface of the manufactured decorative molded product. In addition, the decorating sheet of FIG. 1 (A) is a basic form, and various other decorative sheets as shown in FIGS. 1 (B) and (C) can be used.

  In the decorative sheet shown in FIG. 1B, the base sheet 2 is composed of a first base sheet 21 and a second base sheet 22, and the primer layer 4, the pattern printing layer 5, and the top sheet 3 are sequentially laminated. It consists of Thus, a layer such as a primer layer or a decoration layer can be provided on the decorative sheet as necessary. The base sheet 2 may have a laminated structure of a plurality of sheets of two or more layers. Further, the decorative sheet shown in FIG. 1 (C) is configured by providing a printed pattern layer 5 on a base material sheet 2 and laminating a surface sheet.

  As the resin for the base sheet 2 or the surface sheet 3, acrylic resin, polyolefin resin, polyester resin, polycarbonate resin, polyamide resin, polystyrene, AS (acrylonitrile-styrene copolymer) resin, polyvinyl chloride, vinyl chloride-acetic acid A single type of vinyl copolymer or a mixture of two or more types is used. The base sheet 2 is formed with a thickness of about 80 to 300 μm, the topsheet is formed with a thickness of about 20 to 300 μm, and the total thickness of the decorative sheet 1 is formed with a thickness of about 100 to 600 μm. The preferred thickness (total thickness) of the decorative sheet 1 is the strength for removing the preform from the preform and mounting it on the injection mold when preforming is performed using a mold different from the injection mold. For reasons such as securing shape retention, the thickness is relatively thick, 300 to 600 μm. Further, when the preforming mold is also used as an injection mold, there is no concern about mold retention and tearing at the time of demolding, so the thickness is relatively thin 100 to 300 μm.

  Examples of the acrylic resin include polymethyl (meth) acrylate, polybutyl (meth) acrylate, methyl (meth) acrylate-butyl (meth) acrylate copolymer, methyl (meth) acrylate-ethyl (meth) acrylate copolymer, methyl ( An acrylic resin such as a (meth) acrylate-styrene copolymer (where (meth) acrylate means acrylate or methacrylate) is used alone or as a mixture of two or more.

Examples of the polyolefin resin include high crystalline non-elastomeric polyolefins such as polyethylene (low density or high density), polypropylene, polymethylpentene, polybutene, ethylene-propylene copolymer, propylene-butene copolymer, etc. Resin or various olefinic thermoplastic elastomers are used. These polyolefin resins may be used alone, or two or more resins may be used in combination. As said olefin type thermoplastic elastomer, the following (1)-(7) can be used, for example.
(1) As described in Japanese Patent Publication No. 6-23278, (A) as a soft segment, the number average molecular weight Mn is 25,000 or more, and the ratio of the weight average molecular weight Mw to the number average molecular weight Mn is Mw / Mn ≦ 7 10 to 90% by mass of atactic polypropylene soluble in boiling heptane, and (B) 90 to 10% by mass of isotactic polypropylene insoluble in boiling heptane having a melt index of 0.1 to 4 g / 10 min as a hard segment, Soft polypropylene made of a mixture of In particular, in order to improve moldability and printability (registration accuracy), the mixing ratio of isotactic polypropylene and atactic polypropylene is set to a lower limit of the mass ratio of atactic polypropylene of 5% by mass or more. The upper limit is 50% by mass or less, and more preferably 40% by mass or less.
(2) A thermoplastic elastomer comprising an ethylene-propylene-butene copolymer. Here, as the butene, any of the three structural isomers of 1-butene, 2-butene, and isobutylene can be used. The following (i) to (iii) are preferred specific examples of the ethylene-propylene-butene copolymer, which is a random copolymer and partially contains an amorphous part.
(I) Those described in JP-A-9-1111055. This is a random copolymer of a terpolymer of ethylene, propylene and butene. The mass ratio of the monomer component is 90% by mass or more of propylene. The melt flow rate is preferably 1 to 50 g / 10 min at 230 ° C. and 2.16 kg. Then, with respect to 100 parts by mass of such a ternary random copolymer, 0.01 to 50 parts by mass of a transparent nucleating agent mainly composed of a phosphoric acid aryl ester compound and a fatty acid amide having 12 to 22 carbon atoms are added. 003 to 0.3 parts by mass are melt kneaded.
(ii) Those described in JP-A-5-77371. This is a terpolymer of ethylene, propylene and 1-butene, and 20 to 100% by mass of an amorphous polypropylene having a propylene component content of 50% by mass or more and 80 to 0% of amorphous polypropylene. It is formed by adding mass%.
(iii) Those described in JP-A-7-316358. This is a terpolymer of ethylene, propylene and 1-butene, and the content of propylene and / or 1-butene is 50% by mass or more with respect to 20 to 100% by mass of the low crystalline polymer, 0.5% by mass of an oil gelling agent such as N-acyl amino acid amine salt or N-acyl amino acid ester is added to a composition in which 80 to 0% by mass of amorphous polyolefin such as isotactic polypropylene is mixed. It will be.
The ethylene-propylene-butene copolymer resin may be used alone,
In addition to the above (i) to (iii), other polyolefin resins may be further mixed as required.
(3) (A) An olefin polymer (crystalline polymer) such as polyethylene, polypropylene, polymethylpentene or the like as described in JP-B-53-21021 is used as a hard segment, and (B) partially-crosslinked ethylene-propylene An olefin-based elastomer obtained by uniformly blending and mixing a monoolefin copolymer rubber such as a copolymer rubber and an unsaturated ethylene-propylene-nonconjugated diene with a terpolymer rubber. In addition, it mixes in the ratio of monoolefin rubber / olefin polymer = 50 / 50-90 / 10 (mass ratio).
(4) (B) Uncrosslinked monoolefin copolymer rubber (soft segment), (A) Olefin copolymer (crystalline, hard segment) and crosslinking agent as described in JP-B-52-34210 An olefin-based elastomer obtained by mixing and heating and applying partial shearing dynamically while applying shear stress. Note that (B) monoolefin rubber / (A) olefin copolymer = 60/40 to 80/20 (mass ratio).
(5) Mixing and heating with peroxides such as (A) isotactic polypropylene, propylene-ethylene copolymer, propylene-butene-1 copolymer, etc., as described in JP-B-56-15741, etc., reduces the molecular weight. Mix and heat the peroxide-decomposable olefin polymer (hard segment) to increase fluidity and (B) peroxides such as ethylene-propylene-copolymer rubber and ethylene-propylene-nonconjugated diene terpolymer rubber. Non-crosslinked, non-crosslinked hydrocarbon rubber (soft segment and fluidity-modifying component), (C) Polyisobutylene, butyl rubber, etc. , Peroxide non-crosslinked hydrocarbon rubber (soft segment and fluidity modifying component), and (D) paraffinic and naphthenic Mineral oil-based softener aromatic like, mixed city, olefin elastomer obtained by dynamically heat-treated in the presence of an organic peroxide. In addition, (A) is 90-40 mass parts, (B) is 10-60 mass parts, (A) + (B) = 100 mass parts, (C) and / or (D) are 5 in this. It becomes a compounding ratio of -100 mass parts.
(6) An olefinic thermoplastic elastomer comprising an ethylene-styrene-butylene copolymer as described in JP-A-2-139232.
(7) The olefin-based thermoplastic elastomer according to (1) to (6), wherein a hydroxyl group or / and a carboxyl group are provided as active hydrogen-containing polar functional groups. For example, an olefinic thermoplastic elastomer having a hydroxyl group introduced by graft polymerization of an ethylene-vinyl alcohol copolymer or the like and a carboxyl group introduced by a copolymer of maleic acid, fumaric acid, itaconic acid or the like is used. Either one or both of these hydroxyl groups and carboxyl groups may be used in combination.

  As the polyester resin, polyethylene terephthalate, polybutylene terephthalate, ethylene-terephthalate-isophthalate copolymer, polyethylene naphthalate, polyester-based thermoplastic elastomer, or the like can be used as the thermoplastic polyester resin. The polyester-based thermoplastic elastomer is a block polymer in which an aromatic polyester having a high crystallinity and a high melting point is used for a hard segment, and an amorphous polyether having a glass transition temperature of −70 ° C. or less is used for a soft segment. For example, polybutylene terephthalate is used for the highly crystalline aromatic polyester having a high melting point, and for example, polytetramethylene ether glycol is used for the amorphous polyether.

  Various additives such as a colorant, a flame retardant, a lubricant, an antioxidant, an ultraviolet absorber, a light stabilizer, and a filler may be added to the base sheet 2 and the surface sheet 3 as necessary. . For example, aluminum hydroxide, magnesium hydroxide, or the like is used as the flame retardant. As the ultraviolet absorber, benzotriazole, benzophenone, fine particle cerium or the like is used. As the light stabilizer, a hindered amine radical scavenger and the like are used. The addition amount of the ultraviolet absorber and the light stabilizer is usually about 0.1 to 5% by mass. Further, as the filler, for example, extender pigments composed of powders such as mica, talc, calcium carbonate, barium sulfate, silica, alumina, and kaolinite are used.

  When the base sheet 2 has a two-layer structure, the two layers may be directly laminated by heat fusion, but may be laminated via an adhesive layer between the layers. A two-component curable urethane resin or the like can be used for the adhesive layer. Further, in order to form a multilayer structure such as two layers without interposing an adhesive layer between the layers, for example, lamination may be performed simultaneously with film formation by a co-extrusion method using a T die. In order to laminate through the adhesive layer, for example, lamination may be performed by a dry lamination method.

  The top sheet 3 is generally formed to be transparent. In addition, it is preferable to add a lubricant such as a hydrocarbon-based lubricant and a fatty acid-based lubricant to the top sheet 3 in order to impart good scratch resistance. This is particularly effective when a transparent acrylic resin is used as the top sheet. As for the addition amount of this lubricant, if the addition amount is too large, the sheet slips in the mold during simultaneous injection molding, and wrinkles, distortion, etc. are likely to occur. Therefore, it is preferable to add the lubricant so that the dynamic friction coefficient of the decorative sheet is 0.2 to 0.9, and the specific addition amount is about 0.1 to 0.5% by mass.

The top sheet 3 and the base sheet 2 are laminated and bonded to each other as _needed by heating to a temperature T _LAMI via a heat-sensitive adhesive layer and inserting and pressing between rollers. The temperature T _LAMI when the base sheet 2 and the top sheet 3 are laminated (laminated) by thermal bonding exceeds the temperature T _PRE when the decorative sheet 1 is preformed by vacuum forming (T _LAMI > T _PRE ). The specific laminating temperature T _LAMI is more than 160 ° C. to 180 ° C. corresponding to the temperature condition at the time of vacuum forming. The upper limit temperature of _TLAMI is preferably set to be equal to or lower than the melting point (or melting temperature) of the top sheet and the base sheet from the viewpoint of preventing breakage, significant deformation, thermal decomposition, and the like of each sheet during lamination bonding.

In general, the decorative sheet 1 has a total sheet thickness of 0.1 to 0.6 mm , a processing temperature when laminating the sheets is 150 ° C. to 180 ° C., and a preforming time using a vacuum forming method. The temperature of the sheet is 120 ° C to 160 ° C. The relationship between the sheet temperature T _PRE at the time of _preforming and the sheet temperature T _LAMI at the time of sheet lamination (laminating) was examined. When T _PRE was fixed at 160 ° C. and T _LAMI was changed, the skin level on the surface of the surface sheet after vacuum forming was very high when T _LAMI was 150 ° C. to 160 ° C. (below the temperature during vacuum forming). It was bad. When _TLAMI was _set to be over 160 ° C. to 180 ° C., the scabbard appearance became inconspicuous visually. Based on this result, the processing temperature at the time of laminating the base sheet and the surface sheet when producing the decorative sheet is set to T _LAMI > T _PRE .

The hull appearance that appears on the top sheet 3 can also be evaluated by the glossiness of the top sheet 3 surface. Specifically, if the surface glossiness of the topsheet 3 in the decorative sheet 1 after vacuum forming is 85 or more (measurement conditions are described in the examples), the crusted appearance is inconspicuous. Therefore, it is preferable to determine the processing temperature T _LAMI when laminating the decorative sheet so that the surface glossiness of the surface sheet after heating during vacuum forming is 85 or more, preferably 90 or more.

  The decoration sheet 1 is subjected to a decoration process as necessary. Specific examples of the decoration treatment include coloring by adding a colorant to the base sheet 2 itself (transparent or opaque coloring), formation of a pattern printing layer on the top sheet 3 or the base sheet 2, formation of a metal thin film layer, and the like. .

  When a coloring agent is added to the base material sheet 2 itself, it is possible to impart concealability and to impart the base color of the decorative sheet. Examples of the colorant include titanium white, antimony white, carbon black, iron black, dial, cadmium red, ultramarine, cobalt blue, yellow lead, titanium yellow and other inorganic pigments, phthalocyanine blue, indanthrene blue, isoindolinone yellow, Organic pigments such as benzidine yellow, quinacridone red, polyazo red, metal pigments composed of scaly foils such as aluminum and brass, pearlescent pigments composed of scaly foils such as titanium dioxide-coated mica, or dyes are used. It is done.

  The pattern printing layer 5 provided on the decorative sheet 1 is patterned with ink (or paint) using a known printing method such as gravure printing, offset printing, silk screen printing, ink jet printing, transfer printing from a transfer sheet, etc. Form. This pattern includes a wood grain pattern, a stone pattern, a cloth pattern, a leather pattern, a geometric figure, a character, a symbol, a solid surface, or a combination of two or more of these. The pattern printing layer 5 can be provided on the front surface, the back surface, both the front and back surfaces, or the interlayer of the base sheet 2 or the top sheet 3.

  The ink (or paint) used for the pattern printing layer 5 includes chlorinated polyolefin such as chlorinated polypropylene as a binder resin, polyester resin, urethane resin, acrylic resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer, cellulose. One type or a mixture of two or more types is used. A known colorant as mentioned in the description of the base material sheet is added to the binder resin to obtain an ink. When printing directly on a substrate sheet made of polyolefin resin, etc., chlorinated polyolefin, urethane resin, etc. are preferable as the binder resin from the viewpoint of adhesiveness, but a primer layer is formed by appropriately selecting an easy adhesion primer. If it does, sufficient adhesiveness can be given even if it uses the other binder resin.

  The metal thin film used for the pattern printing layer 5 is formed by using a metal such as aluminum, chromium, gold, silver, copper, or the like by a method such as vacuum deposition or sputtering. Alternatively, these methods may be combined. The metal thin film may be provided on the entire surface or partially provided.

  The primer layer 4 is appropriately provided between the layers or on the side of the molded body of the base sheet in order to improve the adhesion by interposing between the layers. The coating liquid such as urethane resin or polyester resin can be used for gravure printing, roll It is formed by a known printing method such as a coat or a coating method. As the urethane resin and the polyester resin, resins exemplified in the adhesive layer are used. Further, instead of forming the primer layer 4, various known easy adhesion treatments may be performed.

  As the adhesive layer of the decorative sheet 1, for example, a two-component curable urethane resin, a polyester resin, or the like is used. The two-component curable urethane resin is a urethane resin composed of a main agent having active hydrogen such as polyol and a crosslinking agent containing isocyanate. The polyol has active hydrogen such as two or more hydroxyl groups in the molecule, and includes, for example, ethylene glycol, propylene glycol, glycerin, trimethylolpropane, 1,2,6-hexanetriol, butenediol, sucrose, Glucose, sorbitol, pentaerythritol, mannitol, triethanolamine, n-methyldimethanolamine, cyclic aromatic and aliphatic and triol, polyethylene glycol, polypropylene glycol, acrylic polyol, polyester polyol, polyether polyol, etc. It is done. As the isocyanate, a polyvalent isocyanate having two or more isocyanate groups in the molecule is used. For example, aromatic isocyanate compounds such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, diphenylmethane-4,4′-diisocyanate, polyphenylmethane polyisocyanate called crude MDI, and xylylene diisocyanate , Isophorone diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, aliphatic or alicyclic isocyanate compounds such as triphenylmethane triisocyanate, hydrogenated isocyanate such as hydrogenated tolylene diisocyanate, hydrogenated diphenylmethane diisocyanate Compounds, or polyisocyanate compounds and low molecular weight glycols or triols such as dipropylene glycol, 1,6-hexanediol, 1,2,6-hexanetriol, trimethyl Reacted with Rupuropan obtained, isocyanate adducts such as an isocyanate-terminated low molecular weight adducts, or isocyanate multimers such as tolylene diisocyanate trimer and the like.

  The polyester resin used for the adhesive layer is, for example, a polycondensation product obtained from a dibasic acid such as phthalic anhydride or adipic acid and a dihydric alcohol such as propylene glycol or ethylene glycol as a thermoplastic polyester resin. Is mentioned. A curable polyester resin may also be used.

  2 (A) to 2 (C) are process diagrams showing an example of the method for producing a decorative molded product of the present invention. In order to manufacture a decorative molded product, first, as shown in FIG. 2A, a decorative sheet 1 and an injection molding machine are prepared, and the decorative sheet 1 is arranged between both male and female molds. As shown in FIG. 2A, the injection molding machine has a male Ma having a runner and a gate that communicates with the injection nozzle, a suction hole 41 on the cavity surface, and a decorative sheet. It consists of a pair of shaping | molding die which consists of female type | mold Mb which also serves as a preforming die. This mold is made of a metal such as iron or ceramics. In the mold open state of the above mold, the decorative sheet 11 (surface decoration layer 5) is supplied between the male mold Ma and the female mold Mb, and the decorative sheet 11 is frame-shaped on the female mold Mb. The sheet clamp 42 is fixed by pressing it or the like. At this time, it inserts so that the back side (base material sheet side) of the decorating sheet 11 may face the gate side so that it is the injection resin side.

Next, as shown in FIG. 2 (B), preforming is performed by vacuum forming on a female mold surface shape of an injection mold at a temperature _TPRE using a decorative sheet. Specifically, in a state where the decorative sheet 11 is fixed to the peripheral edge of the cavity of the parting surface of the female Mb by the clamp 42, the decorative sheet 11 is heated and softened by the heater 43 to perform preheating, The decorative sheet 11 is attracted to the cavity surface of the female mold Mb by vacuum suction from the suction hole 41 of the female mold Mb. In FIG. 2B, the heater 43 is heated by non-contact radiant heating, but may be conductive heating by contact. Further, vacuum forming may be performed by using vacuum / compressed air together with compressed air.

The heating temperature T _PRE at the time of vacuum forming is the same temperature as the thermal bonding temperature T _{LAMI of the} decorative sheet or a temperature lower than T _LAMI .

  Next, as shown in FIG. 2 (C), the heater 43 is retracted from between the two molds, and the preformed decorative sheet is mounted on the female mold of the injection mold. Both molds with the male mold Ma are closed, and a molding resin 44 in a fluid state such as a heat-melted state is injected and filled into a cavity formed between the two molds. Thereafter, the fluidized resin is solidified. The resin is solidified by cooling if it is a molten resin, or by a curing reaction if it is an uncured curable resin.

  When the resin is solidified, both molds are opened and the resin molded body is taken out of the mold. As shown in FIG. 4, a decoration in which a decorative sheet 1 composed of a base sheet 2 and a surface sheet 3 is laminated and bonded to the surface of a resin molded body 6 so that the surface sheet is positioned on the outermost surface of the resin molded body. A molded product 7 is obtained.

  In the production method of the present invention, the preforming of the decorative sheet is performed by using the injection mold as the vacuum mold as shown in FIGS. 2 (A) to (C). Before supplying the sheet, a so-called off-line preforming form in which the decorative sheet is vacuum-formed using another vacuum forming die outside the mold can be used. In addition, the preforming is preferably performed in such a manner that the injection mold is also used as a vacuum mold in terms of efficient and accurate lamination. In the present invention, vacuum forming includes vacuum / pressure forming.

  3A to 3C show a case where a decorative molded product is manufactured by vacuum forming a decorative sheet using a vacuum forming mold different from the injection mold. In this case, first, as shown in FIG. 3A, a vacuum forming die 8 prepared separately from a female die for injection molding is used. The vacuum forming die 8 is provided with suction means such as a suction hole 9. The decorative sheet 1 is appropriately fixed to the peripheral edge of the concave portion of the vacuum forming die 8 with a frame-shaped clamp 10 or the like, and the decorative sheet 1 is heated by appropriate means to be softened and sucked from the suction holes. Vacuum forming is performed so that the decorative sheet 1 conforms to the female surface shape of the vacuum forming die (which may be completely the same shape, but may be substantially the same shape). Thus, the preforming is completed.

  Next, as shown in FIG. 3 (B), the concave portion of the female die 11 of the injection molding die composed of the female die 11 and the male die 12 having no suction means for the decorative sheet 1 preformed by the vacuum forming die. 3 and fixed with a sheet clamp 13, etc., and then, as shown in FIG. 3C, both male and female molds are clamped, and a cavity formed by both molds is filled with resin 44 in a fluid state such as a heat-melted state. To do. Once the resin has solidified, when both molds are opened and the resin molded body is taken out of the mold, the surface sheet is placed on the surface of the resin molded body 6 so that the topsheet is positioned on the outermost surface of the resin molded body as shown in FIG. A decorative molded product 7 obtained by laminating and adhering the decorative sheet 1 composed of the base sheet 2 and the top sheet 3 is obtained.

  As the injection molding resin constituting the resin molding in the production method of the present invention, conventionally known resins used in the injection molding simultaneous painting method can be used, and are appropriately selected according to the required physical properties, cost, etc. of the product. . In particular, it is preferable in terms of adhesion and the like that the same kind of injection molding resin and the same kind of resin of the base sheet of the decorative sheet are used. Injection molding resins include thermoplastic resins such as ABS (acrylonitrile / butadiene / styrene copolymer) resin, AS (acrylonitrile / styrene copolymer) resin, polystyrene, polyvinyl chloride, polyolefin resin, acrylic resin, and polycarbonate resin. Examples thereof include those that have been melted by heating into a liquid or fluid state, or two-component curable resins and catalyst curable resins, such as uncured liquids such as urethane resins and polyester resins.

  The injection-molded resin may be formed without adding a colorant, and the resin molded body 7 may be formed to be colorless and transparent. However, in general, to provide concealability and to impart a desired color tone to the decorative molded product itself. In addition, a colorant is added. This colorant includes inorganic pigments such as titanium white, antimony white, carbon black, iron black, dial, cadmium red, ultramarine, cobalt blue, yellow lead, titanium yellow, phthalocyanine blue, indanthrene blue, isoindolinone yellow, Organic pigments such as benzidine yellow, quinacridone red, polyazo red, metal pigments composed of scaly foils such as aluminum and brass, pearlescent pigments composed of scaly foils such as titanium dioxide-coated mica, or dyes are used. It is done.

  The decorative molded product obtained by the production method of the present invention can be used for various applications such as surface materials such as home appliances and office equipment, vehicle interior materials such as automobiles, packaging containers, and household goods.

[Production example of decorative sheet]
In the layer configuration shown below, a top sheet and a base sheet (which may be a sheet composed of a first base sheet and a second base sheet) are stacked, and the temperature of both sheets is 157 ° C. (Comparative Example 1) ~ 4) or 180 ° C (Examples 1 to 4) heated at two different temperatures and softened (this temperature corresponds to T _LAMI ), with a mirror metal roller (40 ° C heat retention) and a silicon rubber coated metal roller By pressing between the layers, the topsheet and the base sheet were laminated and laminated to produce a decorative sheet with a printed pattern.

[Example 1 and Comparative Example 1 ]
A transparent acrylic resin surface sheet (PMMA, thickness 0.125 mm) and pattern printing ink (a 1: 1 mass ratio mixture of vinyl chloride-vinyl acetate copolymer and acrylic resin as a binder resin, Gravure printing of wood grain pattern using chrome lead, carbon black, and titanium white pigment added) to provide pattern printing layer, urethane primer layer (main component is acrylic polyol, crosslinking agent is isophorone diisocyanate 2) Liquid curable urethane resin (thickness: 2μm), adhesive layer (chlorinated polypropylene resin, thickness: 4μm) are formed in sequence, and a polypropylene resin base sheet (pigment and carbon black pigment is added to conceal the color. Sheet, thickness 0.3 mm) were laminated and laminated to obtain decorative sheets A 1 and A ′ shown in Table 1 .

[Example 2 and Comparative Example 2 ]
A transparent acrylic resin surface sheet (MMA, thickness 0.125 mm) with pattern printing ink (acrylic urethane resin as a binder resin to which a pigment consisting of petal, yellow lead, carbon black, and titanium white is added. ) Is used for gravure printing to provide a pattern printing layer, and a urethane primer layer (two-component curable urethane resin consisting mainly of acrylic polyol and cross-linking agent is isophorone diisocyanate, thickness 2 μm) is formed sequentially. First base sheet made of resin (sheet made of colored petrol and carbon black to make it color concealable, thickness 0.08 mm), and second base sheet made of polypropylene resin (pete and carbon Laminated by laminating a sheet with a color concealing property by adding a pigment made of black (thickness 0.3 mm) And reports open sheet B decorative shown in Table 1, to obtain a B '.

[Example 3 and Comparative Example 3 ]
A transparent acrylic resin surface sheet (MMA, thickness 0.125 mm) and pattern printing ink (a 1: 1 mass ratio mixture of vinyl chloride-vinyl acetate copolymer and acrylic resin as a binder resin, Gravure printing of wood grain pattern using chrome lead, carbon black, and titanium white pigment added ink, providing pattern printing layer, first base sheet made of vinyl chloride resin sheet And a pigment made of carbon black to make the color concealable, a sheet added with a plasticizer dioctyl phthalate 8PHR, thickness 0.1 mm) and a second substrate sheet made of acrylonitrile-butadiene-styrene copolymer (ABS) resin (A sheet made of ABS resin with a petrol and carbon black pigment added to conceal the color, thickness 0.28 m ) Laminating a laminate to the decorative sheet C shown in Table 1, to obtain a C '.

[Example 4 and Comparative Example 4 ]
A transparent acrylic resin surface sheet (MMA, thickness 0.125 mm) and pattern printing ink (one-to-one mass ratio mixture with vinyl chloride-vinyl acetate copolymer resin) are used as a binder resin. , Carbon black, and titanium white (ink added with a pigment), and gravure printing the wood grain pattern, base sheet made of acrylonitrile-butadiene-styrene copolymer (ABS) resin (ABS resin and petrol and carbon Sheets having a color concealing property by adding a pigment made of black and having a thickness of 0.4 mm were laminated and laminated to obtain decorative sheets D 1 and D ′ shown in Table 1 .

[Heating test for decorative sheet]
A heating test was performed using the decorative sheets of Examples 1 to 4 described above. This simulates the sheet temperature at the time of preforming (vacuum forming), and the temperature is 80 ° C. to 180 ° C. (this heating temperature is slightly lower than the lower limit of the temperature T _PRE of normal preforming, After leaving for 1 minute in an oven set at a temperature corresponding to the upper limit of the pre-forming temperature _TPRE ), the surface state of the sheet was visually observed. Table 1 shows the results of the heating test.

評価 ○：柚肌が見られない。
△：目立つ程度の柚肌が確認された。
×：柚肌がはっきりと確認され、しかも程度が悪かった。

Evaluation ○: No skin is seen.
(Triangle | delta): The skin skin of the conspicuous grade was confirmed.
X: The skin was clearly confirmed and the degree was poor.

* 1: The glossiness after heating at 180 ° C. for 1 minute of the decorative sheets A 1 and A ′ of Example 1 and Comparative Example 1 was measured. The measurement results are shown in Table 2 below. The apparatus and measurement conditions used for the measurement are as follows. For comparison, the glossiness of only the unheated surface sheet (unlaminated surface sheet single layer) was also measured under the same conditions.
・ Measuring device: Gross METER "GM3D" manufactured by Color Technology Laboratory Co., Ltd.
・ Measurement conditions: Incident angle 60 degrees

(A)-(C) are sectional drawings which show the aspect of the sheet | seat for decorating used for this invention manufacturing method. (A)-(C) are process drawings which show an example of the manufacturing method of this invention decorative molded product. (A)-(C) are process drawings which show the other example of the manufacturing method of this invention decorative molded product. It is sectional drawing which shows an example of the decorative molded product obtained by this invention manufacturing method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sheet for decoration 2 Base material sheet 3 Top sheet 6 Resin molded object 7 Decoration molded product

Claims (3)

A sheet formed by laminating a base sheet made of polypropylene and a surface sheet made of a transparent acrylic resin and a lubricant in a proportion of 0.1 to 0.5% by mass with respect to the resin by thermal bonding at a temperature T _LAMI . A decorative sheet is prepared, and vacuum molding is performed at a temperature T _PRE using the decorative sheet, so that the female mold surface shape of the injection mold is preformed, and the preformed decorative sheet is injected. Close the injection-molded female and male molds while they are mounted on the female mold, and inject and fill the fluidized resin into the cavity formed between the two molds to solidify it. The decorative sheet is manufactured by laminating and adhering the decorative sheet to the surface of the molded article at the same time, and the temperature T _LAMI of the thermal bonding of the decorative sheet and the preliminary of the decorative sheet the relationship between the temperature _{T PRE} of molding _{T LAM} > Set to _{T PRE,}
And method of manufacturing the decorative molded article, which comprises a 160 ° C. Ultra to 180 ° C. The _{T LAMI.} The method for producing a decorative molded product according to claim 1, wherein the surface glossiness (measured value at an incident angle of 60 degrees) in the decorative sheet after vacuum forming is 85 or more. The method for producing a decorative molded product according to claim 1 or 2, wherein a total sheet thickness of the decorative sheet is 0.1 to 0.6 mm.

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