JP2013226815A - Decorative sheet, preform molding and decorative molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a decorative sheet for solving a problem of defective appearance such as roughness of a surface and generation of wrinkle of a welded part caused when a preform molding is insertion-injection molded, and for manufacturing a preform molding superior in formativeness of deep drawing shape.SOLUTION: Concerning a decorative sheet provided with a decorative resin layer having a decorated surface and a resin film deposited on a rear face side of the decorative resin layer, the resin film is a decorative sheet of the film of a polymer alloy including a polycarbonate-based resin and at least one or more kinds of resin which is immiscible to the polycarbonate-based resin and has a lower softening temperature than the polycarbonate-based resin. In addition, the preform molding using it is used.

Description

  The present invention relates to a decorative molded body having an appearance decorated like leather, for example, a preform molded body for manufacturing the same, and a decorative sheet.

  Decorative molded bodies are known as casings for mobile phones, mobile devices, home appliances, interior parts such as vehicles and airplanes, exterior members such as building materials and furniture. The decorative molded body is molded by, for example, hot pressing a resin sheet with a decorated surface, and then molding the resulting preform molded body into a mold cavity and injection molding. Is done.

  For example, Patent Document 1 below has a porous layer formed by peeling a release substrate from a porous layer formed on a release substrate, and is arranged so as to be the surface of a molded article having a three-dimensional shape. Disclosed is a decorative sheet for performing decorative molding. Patent Document 2 below discloses a decorative sheet in which a urethane adhesive layer and a urethane skin layer are laminated on the surface of a thermoplastic elastomer layer made of an acrylic elastomer or the like. When a preform molded body is molded with such a decorative sheet mainly composed of an elastomer layer, the elastomer layer has a low glass transition temperature (Tg) and is easily softened and stretched by heating, but is difficult to solidify in a short time. There was a problem in that the setability was poor and it was difficult to obtain the desired shape because it was out of shape at the time of mold release.

  The following Patent Document 3 is made of fibers having a fineness of 0.05 denier or more, and a reinforcing sheet having a thickness of 0.1 to 0.6 mm is bonded to the back of an artificial leather having a thickness of 0.4 to 1.0 mm. Disclosed is a decorative sheet having a suede-like or silver-like feel, a preform molded body obtained by molding the decorative sheet, and an insert molded body molded using the preform molded body. The reinforcing sheet is arranged for the purpose of reinforcing the form stability of the preform molded body and suppressing the deformation of the preform during the molding of the preform. And it discloses that sheets, such as a polycarbonate (PC), an ABS resin, a urethane resin, polyolefin, a polyethylene terephthalate (PET), a polybutylene terephthalate (PBT), a nylon resin, are used as a reinforcement sheet.

  Further, the following Patent Document 4 is obtained by forming a three-dimensional shape by press-molding a decorative sheet made of a fiber entangled body of a specific ultrafine fiber bundle and a polymer elastic body. Disclosed is a decorative molded body in which a leather-like appearance is imparted to the surface by placing the preform molded body in a mold cavity and performing injection insert molding. The decorative sheet has a foamable resin such as a foamed polyolefin sheet, a foamed urethane sheet, and a foamed polystyrene sheet that stretches easily during preform molding on its back surface, a polyester-based thermoplastic elastomer sheet, and a polyamide-based thermoplastic. It is disclosed that an elastic resin sheet made of a thermoplastic elastomer such as an elastomer sheet or a fluorinated thermoplastic elastomer sheet may be bonded as a support substrate.

JP 2008-291089 A JP 2010-247457 A Japanese Patent Application Laid-Open No. 2006-281592 JP 2010-235858 A

  When a preform molded body is inserted into a mold cavity of a molding machine and injection molded, there is a problem that the surface of the preform molded body placed in the mold cavity tends to be rough due to the influence of resin pressure and resin temperature. . In particular, in recent years, a thin casing having a thickness of 1 mm or less has been demanded from the viewpoint of reducing the weight of mobile phones, mobile devices, and home appliances. In thin insert molding, the resin peak pressure in the mold during injection molding is remarkably increased. In such a case, high temperature and high pressure are applied to the preform molded body. For this reason, there are problems such as the occurrence of roughness due to the high temperature and high pressure of the injection resin on the surface of the preform molded body, and the wrinkle pattern disappearing.

  Furthermore, when forming a thin molded article by injection insert molding, there are the following problems caused by the flow of molten resin. When a preform molded body is placed in the cavity of the mold during injection insert molding and the molten resin is injected into the mold, when molding a molded product having a thin part or a long part, a plurality of gates are used. A multi-point gate mold for injecting molten resin is employed. In the case of a multipoint gate, a weld line is usually formed at a portion where the ends of the molten resin flowing from different flow paths merge.

  For example, as shown in FIG. 10A, in the mold 50, in the vicinity of the weld line forming portion WL of the molten resin 32 that flows in the direction of the arrow from different flow paths and associates, the molten resin 32 and preform molding are performed. The surface of the preform molded body 60 is pulled in opposite directions across the weld line forming portion WL due to frictional resistance with the body 60, and the molten resin is solidified, so that the ridge S may be formed. Further, when injection is performed at a high speed and a high pressure in order to completely fill the thin portion, as shown in FIG. 10B, the end surface E of the preform molded body 60 is stretched at the end surface of the cavity of the mold 50 and molded. There is a problem that the length of the end face E changes with each shot and the production stability becomes unstable.

  The present inventors have found that the above-mentioned problems are somewhat reduced when a film of a resin having a relatively high heat resistance such as PC is bonded to the back surface of the preform molded body. This is considered to be because the influence of heat or the like applied to the decorative layer on the front surface side of the preform molded body is alleviated by providing a film layer on the back surface of the preform molded body. For example, when a resin film having a low softening temperature such as ABS resin is bonded, the effect of reducing the above-described problems is low.

  However, when PC films were bonded, the following new problems were found. When a decorative sheet with a PC film is preformed, for example, when trying to form a deep drawing shape with corners, the corners are rounded and shaped into an accurate shape. There was a problem that it was difficult. Moreover, the decorative sheet bonded with PC also has a problem that it is difficult to solidify quickly after molding and the setting property is insufficient.

  The present invention solves the problem of poor appearance such as rough surface and generation of wrinkles in the weld part, which occurs when a preform molded body is injection-insert molded, and has excellent deep-drawn shape forming properties It aims at providing the decorating sheet for manufacturing a molded object.

  One aspect of the present invention is a decorative sheet comprising a decorative resin layer having a decorated surface and a resin film deposited on the back side of the decorative resin layer, the resin film being a polycarbonate-based resin The decorative sheet is a polymer alloy film containing at least one kind of resin that is incompatible with the resin and the polycarbonate resin and has a softening temperature lower than that of the polycarbonate resin. Such a decorative sheet is shaped so that the corners are firmly formed even in the case of forming a good shape by hot pressing, particularly a deep drawing shape having corners.

  Further, when the resin incompatible with the polycarbonate resin is selected from a polyethylene terephthalate resin and an ABS resin, the resin has particularly excellent formability. Moreover, it is easy to extend especially when an ABS resin is included. In addition, when a polyethylene terephthalate resin is included, it is particularly excellent in setability for solidifying in a short time without losing its shape.

  Moreover, it is preferable that a decorative resin layer contains the fiber entanglement of the ultrafine fiber with an average fineness of 0.9 dtex or less, and the crosslinked non-foamed polyurethane impregnated in the fiber entanglement. The ultrafine fiber is excellent in formability because it is softened at a relatively low temperature and is easily stretched when softened even though it is excellent in fulfillment because it forms a dense fiber structure. In addition, by including a cross-linked non-foamed polyurethane, deformation due to elastic recovery after release of the preform molding that occurs when the non-cross-linked foamed polyurethane is contained is suppressed. Excellent stability. The ultrafine fiber is particularly preferable because it contains a polyester having a glass transition temperature (Tg) of 120 ° C. or less because it easily stretches during preform molding. The decorative resin layer may be a layer containing a porous or non-porous elastomer.

  Another aspect of the present invention is a preform molded body used as an insert molding material, which is a preform molded body obtained by molding any one of the above decorative sheets into a three-dimensional shape by hot pressing.

  Another aspect of the present invention is a decorative molded body obtained by disposing the preform molded body in a mold and injection molding a thermoplastic resin. As a decorative molded body, the resin film does not melt at the molding temperature of injection molding, has a higher elastic modulus (E ′) than the elastic modulus (E ′) of the thermoplastic resin, or the melt viscosity of the thermoplastic resin. It is preferably made of a resin having a higher melt viscosity. According to such a structure, the influence by the heat | fever and the pressure which the molten resin which flowed in in the metal mold | die gives to a decorating resin layer, and the influence by contact resistance can be relieved. As a result, surface defects such as surface roughness, generation of wrinkles at the welds, and instability of molding dimensions are suppressed. The elastic modulus (E ′) at the molding temperature of the injection molding of the resin film is particularly preferably 0.05 MPa or more.

  In addition, a decorative sheet provided with a resin film containing at least one selected from a polyethylene terephthalate resin and an ABS resin as a resin incompatible with a polycarbonate resin was obtained by molding into a three-dimensional shape by hot pressing. A decorative molded body obtained by placing a preform molded body in a mold and injection-molding an ABS resin is preferable from the viewpoint of particularly suppressing appearance defects and instability of molding dimensions.

  In addition, a preform formed by molding a decorative sheet with a resin film that is a polyethylene terephthalate resin as a resin incompatible with a polycarbonate resin into a three-dimensional shape is placed in a mold. And the decorative molded body obtained by injection-molding a polycarbonate-type resin is also preferable from the point which the external appearance defect and the instability of a molding dimension are suppressed especially.

  ADVANTAGE OF THE INVENTION According to this invention, the decorating sheet which is excellent in the shaping property of the deep drawing shape at the time of shape | molding a preform molded object is obtained. Further, by performing injection insert molding of such a preform molded body, it is possible to obtain a decorative molded body which is suppressed in appearance defects such as surface roughness and generation of wrinkles in the weld portion and excellent in dimensional stability.

FIG. 1 is a schematic cross-sectional view of a decorative sheet 10 of the present embodiment. FIG. 2 is a schematic view showing an example of a mold surface shape of a mold 5 for molding a deep-drawn preform. FIG. 3 is a process explanatory diagram illustrating a process of forming the preform molded body 20 using the decorative sheet 10. FIG. 4 is a schematic diagram for explaining the formability of the preform molded body. FIG. 5 shows SS curves at 20 ° C., 120 ° C., and 150 ° C. for PC sheets, PET sheets, and PC / PET sheets. FIG. 6 shows SS curves at 20 ° C., 120 ° C., and 150 ° C. of the PC sheet, ABS resin sheet, and PC / ABS resin sheet. FIG. 7 is a process explanatory diagram for explaining injection insert molding using the preform molded body 20. FIG. 8 is a schematic cross-sectional view of the decorative sheet 40 of the present embodiment. FIG. 9 is an explanatory diagram for explaining the formability evaluation in the example. FIG. 10 is a schematic cross-sectional view for explaining problems that occur when injection insert molding is performed using a conventional decorative sheet.

  Hereinafter, preferred embodiments of the decorative molded body according to the present invention will be described. FIG. 1 is a schematic cross-sectional view of a decorative sheet 10 of the present embodiment. In FIG. 1, 1 is a decorative resin layer having a textured pattern 1a as a decorated surface, and 2 is a resin film. The resin film 2 is a polymer alloy film containing a polycarbonate resin (PC) and a resin that is incompatible with PC and has a softening temperature lower than that of the polycarbonate resin.

  The decorative resin layer is a flexible resin layer having a decorated surface such as a textured pattern, a raised surface such as a suede tone, a glossy surface of enamel tone, a printed pattern of any design, and the like on the surface. Specific examples of the resin layer include artificial leather, synthetic leather, PVC leather, and a sheet made of a porous or non-porous elastomer.

  The artificial leather is a sheet mainly composed of a fiber entangled body (nonwoven fabric) in which fibers are entangled three-dimensionally and impregnated with a polymer elastic body such as polyurethane. Synthetic leather is a laminate of a resin layer made of a polymer elastic material such as polyurethane or polyvinyl chloride on a two-dimensionally entangled fiber base material such as woven fabric or knitted fabric, and the surface of the resin layer is embossed. This is a sheet provided with a leather-like pattern such as a texture pattern. Examples of the sheet made of a porous or non-porous elastomer include a sheet that does not include a fiber base material and that is provided with a texture pattern or the like on the surface of an elastomer sheet such as porous or non-porous polyurethane. .

  The thickness of the decorative resin layer is not particularly limited, but is preferably 0.25 to 0.95 mm, more preferably 0.25 to 0.75 mm.

  The resin film is a polymer alloy film containing a resin that is incompatible with PC and has a softening temperature lower than that of the polycarbonate resin. Such a PC polymer alloy film has an excellent balance between heat resistance and formability.

  Specific examples of the resin film include a polymer alloy film of PC and polyethylene terephthalate resin (PET), a polymer alloy film of PC and ABS resin such as acrylonitrile-butadiene-styrene resin, and PC and acrylonitrile-styrene resin. And a polymer alloy film with an AS-based resin. In such a polymer alloy film, since the PC and the other resin form a matrix-domain structure, the characteristics of the PC and the other resin are exhibited independently without being mixed.

  It is preferable that mass ratio (PC / other resin) of PC and other resin incompatible with the resin film is 90/10 to 10/90, more preferably 70/30 to 40/60. When the proportion of PC is too low, the heat resistance is lowered, and when the proportion of other resins is too low, the formability tends to be lowered.

  The thickness of the resin film is preferably about 0.05 to 0.35 mm, more preferably about 0.1 to 0.3 mm. When the resin film is too thick, there is a tendency that the flexibility of the decorative resin layer is lowered and the texture is lowered, or the moldability of the preform molding is lowered. When the resin film is too thin, the resin film is easily softened or melted in the mold during injection molding, and the decorative resin layer tends to soften or melt due to the heat of the molten resin.

  As a specific example of the method of laminating the resin film on the decorative resin layer, for example, a dry lamination method in which the resin film and the decorative resin layer are bonded or thermocompression bonded via an adhesive is preferably used. . The adhesive is not particularly limited, but for example, a hot melt adhesive that can be stretched by heat is preferably used. The thickness of the adhesive layer is not particularly limited, but is preferably about 0.02 to 0.1 mm.

  Next, a method for producing a preform molded body by hot press molding a decorative sheet into a three-dimensional shape will be described. In the present embodiment, press molding will be described in detail. However, instead of press molding, other preform molding methods such as vacuum molding, pressure molding, and vacuum / pressure molding, which are conventionally known, may be used.

  FIG. 2 is a schematic perspective view of a mold 5 for forming a deep-drawn preform having a substantially square top surface and a trapezoidal cross section. In FIG. 2, 5a is a male upper mold and 5b is a female lower mold.

  With reference to FIG. 3, the process of preforming the decorative sheet 10 using the mold 5 will be described. In the preform molding, first, as shown in FIG. 3A, the resin sheet 2 faces the upper mold 5a of the decorative sheet 10 softened by heating, and the decorative resin layer 1 is the lower mold 5b. It arrange | positions between the upper metal mold | die 5a and the lower metal mold | die 5b in the direction which opposes. Then, as shown in FIG. 3B, the upper mold 5a and the lower mold 5b are clamped to form the softened decorative sheet 10. Specifically, the temperature for softening by heating is preferably 120 to 180 ° C., more preferably about 130 to 170 ° C., for example.

  Then, the upper mold 5a and the lower mold 5b are opened as shown in FIG. Then, the preform 20 ′ obtained as shown in FIG. 3 (d) is released. Then, as shown in FIG. 3 (e), unnecessary portions around the preform 20 'are trimmed and removed so as to follow the shape of the cavity of the injection insert molding die. In this way, a preform molded body 20 is obtained which is molded so as to follow the shape of the cavity of the mold for injection insert molding.

  By using the decorative sheet of this embodiment in the molding of the preform molded body as described above, the corners are firmly formed even when molding a deep drawing shape having good shapeability, particularly corners. So shaped. Specifically, when a deep-drawn preform is formed with a decorative sheet, the corner of the rising portion of the mountain skirt and the corner in contact with the top surface as shown by R in FIG. It can be shaped like a fold angle. In addition, when a PET sheet or a PC sheet is used as the resin film, the shape may have a rounded corner as shown in FIG. The reason for this is not exactly understood, but is thought to be due to the following reasons.

  FIG. 5 shows SS curves at 20 ° C., 120 ° C., and 150 ° C. of a PC sheet, a PET sheet, and a PC / PET sheet of PC / PET = 50/50, each having a thickness of 0.2 mm. FIG. 6 shows SS curves at 20 ° C., 120 ° C., and 150 ° C. of an ABS resin sheet, PET sheet, and PC / ABS resin = 50/50, each having a thickness of 0.2 mm.

  As shown in FIG. 5, when the temperature is 150 ° C., which is close to the preform molding temperature, the PC sheet has a tensile strength that is not too high at 150 ° C., but breaks before it stretches sufficiently because the elongation at break is low. Further, since the tensile strength of the PET sheet increases as the elongation rate increases, it seems that the PET sheet is not easily stretched during pressing in preform molding. On the other hand, it can be seen that the tensile strength of PC / PET sheet is extremely low without rising even when the elongation is increased at 150 ° C., and the elongation is not broken even when the elongation is 400% or more. From these results, it is considered that the PC / PET sheet is easy to stretch even when it is shaped under the heating of preform molding and has excellent formability. Similarly, referring to FIG. 6, even in the case of a PC / ABS sheet, even at 150 ° C., the tensile strength does not rise even if the elongation rate is high, and it does not break even if the elongation rate exceeds 400%. You can see that it is growing. For this reason, a polymer alloy film containing a resin that is incompatible with PC and PC and has a softening temperature lower than that of a polycarbonate resin, such as a PC / PET sheet or a PC / ABS sheet, is used during preform molding. Excellent formability.

  As shown in FIG. 5, the tensile strength of the PC / PET sheet is somewhat higher at 120 ° C. and higher than that at the PC sheet at 20 ° C. This indicates that the tensile strength of the PC / PET sheet is particularly high in temperature dependence and is easily solidified by cooling after preform molding. On the other hand, for example, the tensile strength of the PC / ABS sheet shown in FIG. 6 is not sufficiently high even at 120 ° C. This seems to be the reason why the PC / PET sheet is superior in setability to the PC / ABS sheet.

  Next, each step of injection insert molding in which the preform molded body 20 is inserted into a cavity of a mold for injection insert molding and a resin is injected onto the back surface of the preform molded body 20 will be described with reference to FIG. explain.

  An injection mold 15 in FIG. 7 includes a movable mold 15a having a cavity 15d having an insert portion, a fixed mold 15b, and a spacer plate 15c for releasing the sprue runner 22 to be formed. Is provided.

  As shown in FIG. 7A, first, the preform 20 is placed in the cavity 15d. Then, as shown in FIG. 7B, the movable mold 15a and the fixed mold 15b are clamped, and the nozzle 16 of the injection molding machine is advanced until it contacts the sprue bush 15f of the fixed mold 15b. The molten resin 21a ′ melted in the cylinder of the injection molding machine is injected into the mold 15. The injected molten resin 21a ′ flows through the resin flow path and flows into the cavity from the two gates 15g and 15h. The molten resin flowing into the cavity from the two gates 15g and 15h associates to form at least one weld line in the molded body 21. And after completion | finish of injection, through a cooling process, as shown in FIG.7 (c), the movable side metal mold | die 15a and the fixed side metal mold | die 15b are mold-opened. Then, the insert molded body 30 in which the preform molded body 20 and the molded body main body 21 molded by injection molding are integrated, and the sprue runner 22 are released.

  As the resin for forming the molded body 21 to be injected by injection insert molding, various thermoplastic resins are used without particular limitation, and are appropriately selected depending on the application. For example, as a resin used for a casing of a mobile phone, a mobile device, a home appliance, etc., a resin having excellent impact resistance such as a polycarbonate resin and an ABS resin can be given.

  A resin film is laminated on a decorative sheet for molding a preform molded body or a preform molded body obtained by preforming it. Such a resin film is disposed on the surface in contact with the molten resin during injection molding. By laminating such a resin film on the back side of the preform molded body, when the preform molded body is injection-insert molded, the thermal effect caused by the direct contact of the molten resin with the decorative resin layer is reduced. can do.

  The resin film preferably does not melt at the molding temperature of injection molding, has an elastic modulus higher than that of the thermoplastic resin, or has a melt viscosity higher than the melt viscosity of the thermoplastic resin. Moreover, it is preferable that the resin film be softened to the extent that it can follow the deformation of the decorative resin layer at the molding temperature of the preform molding lower than the injection molding temperature. The molding temperature in the present invention means the nozzle temperature of an injection molding machine. In such a case, the resin pressure applied in the mold is relaxed at the interface between the decorative resin layer and the resin film. As a result, it is possible to suppress the decorative resin layer from being damaged by the influence of the resin pressure and the resin temperature of the molten resin. Further, since the molten resin flowing in the mold comes into contact with the resin film, the decorative resin layer is suppressed from being pulled by frictional resistance due to contact with the molten resin. As a result, wrinkles S occur near the weld line on the surface of the preform molded body as shown in FIG. 10A, or the end face E extends due to frictional resistance as shown in FIG. 10B. It is suppressed.

  The type of the resin film is preferably selected as appropriate in relation to the type of resin to be injected and the type of decorative resin layer in injection molding. Specific examples of the combination include the following combinations.

  When the thermoplastic resin is an ABS resin, the nozzle temperature of the injection molding machine is set in a range of about 190 to 270 ° C., depending on the grade. In this case, for example, when an ABS resin is injection molded at a nozzle temperature of 230 ° C., it does not melt at 230 ° C., has an elastic modulus higher than that of the ABS resin at 230 ° C., or ABS at 230 ° C. A film made of a resin having a melt viscosity higher than that of the base resin is selected as the resin film. Specific examples thereof include a polymer alloy of PC and ABS resin that does not melt at 230 ° C. or high melt viscosity, and a resin film of a polymer alloy of PC and PET.

  When the thermoplastic resin is a polycarbonate-based resin, the nozzle temperature of the injection molding machine is set in the range of about 280 to 320 ° C., depending on the grade. In this case, for example, when a polycarbonate resin is injection-molded at a nozzle temperature of 280 ° C., it does not melt at 280 ° C., has an elastic modulus higher than that of the polycarbonate resin at 280 ° C., or polycarbonate at 280 ° C. A film made of a resin having a melt viscosity higher than that of the base resin is selected as the resin film. Specific examples thereof include a film made of an alloy of PC and PET having an elastic modulus at 280 ° C. higher than the elastic modulus at 280 ° C. of the polycarbonate resin to be injected or a high melt viscosity.

  The melting temperature of the resin film is determined by, for example, fixing a test piece having a width of 5 mm and a length of 30 mm between chucks with an interval of 20 mm using a dynamic viscoelasticity measuring device (for example, FT Rheospectra DDVIV manufactured by Rheology). In an elastic modulus (E ′) spectrum obtained by measuring dynamic viscoelastic behavior under conditions of a measurement region of 30 to 300 ° C., a heating rate of 3 ° C./min, a strain of 5 μm / 20 mm, and a measurement frequency of 10 Hz, It can be said that the temperature shows the maximum temperature. When the melting temperature of the resin film is higher than the nozzle temperature of the injection molding machine, it can be said that the resin does not melt at the injection molding temperature.

  The heat modulus and pressure applied to the decorative resin layer by the molten resin flowing into the mold is 0.05 MPa or more as the elastic modulus at the molding temperature of the injection molding of the resin film, and further 0.1 to 1.0 MPa. It is preferable from the point that the influence by the contact resistance and the influence by the contact resistance can be further reduced.

  In addition, the softening temperature of the resin film is determined by, for example, fixing a test piece having a width of 5 mm and a length of 30 mm between chucks with an interval of 20 mm using a dynamic viscoelasticity measuring apparatus (for example, FT Leospectra DDVIV manufactured by Rheology). In the viscoelastic spectrum obtained by measuring the dynamic viscoelastic behavior under the conditions of a measurement region of 30 to 300 ° C., a heating rate of 3 ° C./min, a strain of 5 μm / 20 mm, and a measurement frequency of 10 Hz, A temperature at which a certain Tan δ is maximized. When the softening temperature of the resin film is lower than the molding temperature of the preform molding, it can be said that the resin film is softened to the extent that it can follow the deformation of the decorative resin layer in the preform molding.

  The resin film preferably has a stress at 30% elongation at 150 ° C. near the temperature at which the preform is molded, of 3 to 40 N / 25 mm, more preferably 5 to 30 N / 25 mm. When the stress at 30% elongation at 150 ° C. is in such a range, in the preform molding, it can easily follow the deformation of the decorative resin layer, and the surface is rough during the injection molding, Appearance defects and instability of molding dimensions tend to be further suppressed.

  Next, as an example of a preferred form of the decorative sheet of the present embodiment, an example in which artificial leather is used as the decorative resin layer will be described in detail.

  FIG. 8 is a schematic cross-sectional view of a decorative sheet 40 using artificial leather as a decorative resin layer. In FIG. 8, 11 is an artificial leather layer, 2 is a resin film, and 3 is a silver surface layer provided on the surface as needed.

  The artificial leather layer 11 includes, for example, a polymer elastic body 11b and a void 11c that bind the fiber entangled body 11a and the fiber entangled body 11a to enhance the shape stability.

  The fiber entangled body forming the artificial leather layer is, for example, a thermoplastic resin having an average fineness of 0.9 dtex or less, further 0.01 to 0.8 dtex, particularly 0.05 to 0.5 dtex. An entangled body of ultrafine single fibers made of When the average fineness is too high, when preforming the decorative sheet, the stretchability at the time of softening by heating is lowered, and it is difficult to accurately transfer the mold shape and the formability tends to be lowered. . Moreover, when the average fineness is too low, it is difficult to produce ultrafine single fibers.

  Specific examples of the thermoplastic resin forming the ultrafine single fiber include, for example, polyethylene terephthalate (PET), modified polyethylene terephthalate, polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polytriethylene terephthalate, polyhexamethylene. Aromatic polyester resins such as terephthalate, polypropylene terephthalate, and polyethylene naphthalate; fats such as polylactic acid, polyethylene succinate, polybutylene succinate, polybutylene succinate adipate, polyhydroxybutyrate-polyhydroxyvalerate copolymer Polyester-based resins: Polyamide 6, Polyamide 66, Polyamide 610, Polyamide 10, Polyamide 11, Polyamide 12, Polyamide 6-12, etc. Amide resin; Polyolefin resin such as polypropylene, polyethylene, polybutene, polymethylpentene, chlorinated polyolefin; Modified polyvinyl alcohol resin formed from modified polyvinyl alcohol containing 25 to 70 mol% of ethylene units; and Examples thereof include crystalline elastomers such as polyurethane elastomers, polyamide elastomers, and polyester elastomers. Among these, a polyester resin having a glass transition temperature (Tg) of 120 ° C. or less is preferable from the viewpoint of excellent preform moldability.

  The polyester having a glass transition temperature (Tg) of 120 ° C. or less includes a modified polyethylene terephthalate containing a copolymer component that disturbs the straight chain structure in the structural unit of aromatic polyethylene terephthalate, in particular, isophthalic acid, phthalic acid, A modified polyethylene terephthalate containing an asymmetric aromatic carboxylic acid such as 5-sodium sulfoisophthalic acid or an aliphatic dicarboxylic acid such as adipic acid as a copolymerization component in a predetermined ratio is preferable. More specifically, modified polyethylene terephthalate containing 2 to 12 mol% of isophthalic acid unit as a monomer component is preferable.

Apparent density of the fiber-entangled body 0.40 g / cm ³ or more, and more preferably from 0.45~0.70g / cm ^3. If the apparent density of the fiber entangled body is too low, there will be dense and sparse parts of the fiber. Arabi) appears. Moreover, when an apparent density is too high, there exists a tendency for a flexible feel to fall.

  In order to make the fiber entangled body have a high apparent density, it is preferable that a plurality of ultrafine single fibers are converged to form a fiber bundle. Specifically, for example, it is preferable that 5 to 1000, further 5 to 200, particularly preferably 10 to 50, and most preferably 10 to 30 ultrafine single fibers form a fiber bundle.

  Moreover, it is preferable that the ultrafine single fiber is a long fiber from the viewpoint of increasing the apparent density. Here, the long fiber means that it is not a short fiber cut by a predetermined length. The length of the long fiber is preferably 100 mm or more, and more preferably 200 mm or more from the viewpoint of sufficiently increasing the fiber density of the ultrafine single fiber. When the length of the ultrafine single fiber is too short, it tends to be difficult to increase the density of the fiber.

  Next, the polymer elastic body that binds the fiber entangled body will be described.

  Specific examples of the polymer elastic body include polyurethane, acrylonitrile elastomer, olefin elastomer, polyester elastomer, polyamide elastomer, acrylic elastomer, and the like. Of these, polyurethanes, particularly crosslinked non-foamed polyurethanes are particularly preferred. Cross-linked non-foamed polyurethane is less susceptible to deformation due to elastic recovery after release from the mold than uncrosslinked foamed polyurethane when molding a preform. As a result, when a deep-drawn preform is molded with a decorative sheet, it can be shaped so that the corner at the rising edge of the mountain skirt and the corner in contact with the top surface have a sharp fold angle. it can.

  When uncrosslinked foamed polyurethane is used, it is deformed due to elastic recovery after being released from the mold, so that it tends to be deformed after release even if it is shaped according to the mold. In particular, when forming a deep-drawn preform, the shape tends to be rounded. When the non-foaming polyurethane as described above is used, the shape is set in the mold by the crosslinked structure, so that it is considered that the deformation due to the elastic recovery after the mold release is suppressed.

  Such a crosslinked non-foamed polyurethane is preferably formed using an aqueous emulsion of a crosslinkable polyurethane. Specific examples of the water-based emulsion of the crosslinkable polyurethane include water-based emulsions of polycarbonate-based polyurethane, polyester-based polyurethane, polyether-based polyurethane, and polycarbonate / ether-based polyurethane that form a crosslinked structure after drying.

  The content of the polymer elastic body in the artificial leather layer is preferably 5 to 25% by mass, more preferably 10 to 22% by mass, and particularly preferably 15 to 22%. When the content of the polymer elastic body is less than 5% by mass, the shape stability tends to decrease. Moreover, when it exceeds 25 mass%, there exists a tendency for the apparent density of an entangled body to fall relatively.

  The artificial leather layer has a silver surface layer for imparting a silver surface-like appearance to the surface thereof. The resin component for forming the silver surface layer is not particularly limited. Specific examples thereof include various polyurethane resins such as polycarbonate polyurethane resins, polyester polyurethane resins, and polyether polyurethane resins, acrylic resins, polyurethane acrylic composite resins, polyvinyl chloride, and synthetic rubbers. . Among these, polyurethane resins are preferable from the viewpoint of excellent adhesiveness, mechanical properties such as wear resistance and flex resistance. The thickness of the silver layer is preferably 0.01 to 0.5 mm, more preferably 0.02 to 0.15 mm, and particularly preferably 0.04 to 0.12 mm.

  The thickness of the artificial leather layer is preferably 0.25 to 0.95 mm, more preferably 0.25 to 0.75 mm. Further, the total thickness of the silver surface layer and the artificial leather layer is preferably 0.25 to 1.00 mm, and more preferably 0.30 to 0.80 mm.

  The laminate composed of the silver surface layer and the artificial leather layer thus obtained has a stress at 30% elongation at 150 ° C. near the temperature for preform molding of 50 N / 25 mm or less, and further 40 N / 25 mm or less. Preferably there is. When the stress at 30% elongation at 150 ° C. is too large, the formability tends to decrease due to the decrease in stretchability in preform molding. In addition, the stress at the time of 30% elongation is attached to a tensile tester so that a rectangular test piece having a width of 25 mm and a length of 200 mm is 50 mm in accordance with JIS L1096 6.12 “Tensile strength test”. It is determined by reading the stress at 30% elongation from the SS curve.

It apparent density of the artificial leather layer grain layer is formed is 0.5 g / cm ³ or more, more 0.50~0.75g / cm ^3, in particular is 0.55~0.70g / cm ³ Is preferred. Since the artificial leather layer has such a high specific gravity, it has a sense of fulfillment. Therefore, the preform molded body obtained is excellent in form stability, and it is suppressed from losing flexibility by being compressed during molding and thinning.

  Next, an example of the manufacturing method of the artificial leather layer which comprises the decorating sheet of this embodiment is demonstrated. Artificial leather layers are (1) a web manufacturing process for producing a long fiber web made of sea-island type composite fibers by melt spinning, and (2) a plurality of the obtained long fiber webs are entangled and entangled. A web entanglement step for forming a sheet; (3) a wet heat shrinkage treatment step for wet heat shrinkage of the web entanglement sheet; and (4) impregnation of the polyurethane emulsion or solution into the web entanglement sheet, and then coagulating the polyurethane. It is obtained by a process comprising a polyurethane impregnation step and (5) an ultrafine fiber forming step of converting the sea-island type composite fiber in the web entangled sheet into an ultrafine single fiber. Each step will be described in detail below.

(1) Web manufacturing process In this process, first, a long fiber web made of sea-island type composite fibers is manufactured by melt spinning. As the long fiber web, for example, a so-called spunbond method is preferably used in which a sea-island type composite fiber is spun by a melt spinning method and is collected on a net without being cut to form a web.

  The sea component of the sea-island composite fiber is extracted or decomposed and removed at an appropriate stage after the web entangled sheet is formed. A fiber bundle composed of ultrafine single fibers can be formed by this decomposition removal or extraction removal.

  As the thermoplastic resin constituting the island component of the sea-island type composite fiber, various thermoplastic resins forming the ultrafine single fiber as described above are used. On the other hand, as the thermoplastic resin that constitutes the sea component of the sea-island composite fiber, a thermoplastic resin that is different from the resin that constitutes the island component in solubility in a solvent or decomposability in a decomposing agent is selected.

  Specific examples of the thermoplastic resin constituting the sea component include, for example, polyethylene, polypropylene, polystyrene, ethylene propylene copolymer, ethylene vinyl acetate copolymer, styrene ethylene copolymer, styrene acrylic copolymer, and polyvinyl alcohol. Resin etc. are mentioned. Of these, polyvinyl alcohol resins, particularly ethylene-modified polyvinyl alcohol resins, are preferred because they are easily contracted by wet heat or hot water.

  A spunbond method is used for spinning and web formation of sea-island type composite fibers. Specifically, sea-island type composite fibers are continuously ejected from individual nozzle holes onto a conveyor belt-shaped mobile net using a composite spinning nozzle in which a large number of nozzle holes are arranged in a predetermined pattern. And depositing while cooling using a high-speed air stream. A web is formed by such a method. The web formed on the net is preferably subjected to a fusion treatment. Form stability is imparted by the fusing process. As a specific example of the fusion process, for example, a hot press process can be cited. As a heat press process, the method of using a calender roll and applying a predetermined pressure and temperature, for example, can be employed.

(2) Web entanglement process Next, a web entanglement sheet is formed by overlapping and entangling about 5 to 100 obtained long fiber webs. The web entangled sheet is formed by performing an entanglement treatment on the long fiber web using a known nonwoven fabric manufacturing method such as needle punching or high-pressure water flow treatment.

Specifically, for example, a silicone-based oil agent or a mineral oil-based oil agent such as a needle breakage preventing oil agent, an antistatic oil agent, or an entanglement improving oil agent is applied to the long fiber web. Then, the entanglement process which entangles a fiber three-dimensionally with a needle punch is performed. By performing the needle punching process, a web entangled sheet having a high fiber density and hardly causing the fiber to come off can be obtained. The basis weight of the web-entangled sheet is appropriately selected according to the target thickness, and specifically, for example, a range of 500 to 2000 g / m ² is preferable from the viewpoint of excellent handleability.

(3) Heat shrinkage treatment step Next, the web entangled sheet is thermally shrunk to increase the fiber density and the degree of entanglement of the web entangled sheet. In this step, the web entangled sheet containing long fibers is thermally shrunk, so that the web entangled sheet is greatly shrunk compared to the case where the web entangled sheet containing short fibers is heat shrunk. Can do. The fiber entangled sheet subjected to the heat shrink treatment may be further increased in fiber density by heating roll or hot pressing.

  The change in the basis weight of the web-entangled sheet in the heat shrinkage treatment step is 1.1 times (mass ratio) or more, further 1.3 times or more, and 2.0 times the basis weight before the shrinkage treatment. It is preferable that it is 2 times or less, and further 1.6 times or less.

(4) Polyurethane impregnation step For the purpose of enhancing the form stability of the web entangled sheet, before or after the ultra-fine fiberization treatment of the web entangled sheet, an aqueous emulsion or solution of polyurethane is applied to the web entangled sheet subjected to the shrinkage treatment. After impregnation, the polyurethane is solidified.

  When impregnating a web entangled sheet with an aqueous polyurethane emulsion or solution, the web entangled sheet is immersed in a bath filled with the polyurethane aqueous emulsion or solution, and then in a predetermined impregnation state with a press roll or the like. A dip nip method is preferably used in which the process of squeezing is performed once or multiple times. As other methods, a bar coating method, a knife coating method, a roll coating method, a comma coating method, a spray coating method, or the like may be used.

  Examples of the polyurethane include various polyurethanes obtained by reacting a polymer polyol having an average molecular weight of 500 to 3000, an organic polyisocyanate, and a chain extender in a predetermined molar ratio.

  Specific examples of the polymer polyol include polymer polyols having an average molecular weight of 500 to 3000, such as polyester diol, polyether diol, polyether ester diol, and polycarbonate diol. Specific examples of the organic polyisocyanate include aromatic isocyanates such as 4,4′-diphenylmethane diisocyanate, alicyclic isocyanates such as isophorone diisocyanate, and aliphatic isocyanates such as hexamethylene diisocyanate. It is done. Examples of the chain extender include low molecular compounds having two or more active hydrogen atoms such as ethylene glycol and ethylenediamine.

  The polyurethane is fixed to the web entangled sheet by impregnating the web entangled sheet with an aqueous emulsion or solution of polyurethane and coagulating it by a wet method or a dry method. In order to crosslink the coagulated polyurethane, it may be cured by heat treatment after coagulation and drying.

(5) Ultrafine fiber formation process The sea-island type composite fibers in the web-entangled sheet are converted into ultrafine fibers by extracting or decomposing and removing sea components with water or a solvent. In the case of a sea-island type composite fiber using a water-soluble resin such as a polyvinyl alcohol-based resin as a sea component, the sea component is removed by a hot water heat treatment with water, an alkaline aqueous solution, an acidic aqueous solution or the like.

  In this step, when the sea component is dissolved from the sea-island type composite fiber to form the ultrafine fiber, the ultrafine fiber is greatly crimped. Since the fiber density becomes dense by this crimping, a high-density fiber entangled body is obtained.

The intermediate sheet of the artificial leather layer 1 having a basis weight of preferably 300 to 1800 g / m ² is obtained by the steps as described above.

  The intermediate sheet of the artificial leather layer obtained in this way is dried and then sliced into multiple pieces in the direction perpendicular to the thickness direction or ground to adjust the thickness and the surface condition. Finished with an artificial leather layer. Moreover, you may provide a silver surface layer on the surface of an artificial leather layer as needed.

  And the decorative sheet which uses an artificial leather layer as a decoration resin layer by laminating a resin film on an artificial leather layer is obtained. As a specific example of the method of laminating the resin film on the artificial leather layer, a dry laminate in which the artificial leather layer is bonded to the resin film for forming the resin film via an adhesive or thermocompression bonding is preferably used. .

  Hereinafter, the present invention will be described more specifically with reference to examples. In addition, this invention is not limited at all by the Example.

[Example 1]
Ethylene-modified polyvinyl alcohol (ethylene unit content: 8.5 mol%, polymerization degree: 380, saponification degree: 98.7 mol%) as a sea component thermoplastic resin, and Tg of 110 ° C. as an island component thermoplastic resin Polyethylene terephthalate modified with isophthalic acid (content of isophthalic acid unit of 6.0 mol%) was melted individually. Then, each molten resin was supplied to a plurality of spinning nozzles in which a large number of nozzle holes were arranged in parallel so as to form a cross-section in which 25 island components having a uniform cross-sectional area were distributed in the sea component. . At this time, it supplied, adjusting pressure so that the mass ratio of a sea component and an island component might become sea component / island component = 25/75. And it was made to discharge from the nozzle hole set to the nozzle | cap | die temperature of 260 degreeC.

  The molten fiber discharged from the nozzle holes is drawn by an air jet / nozzle type suction device in which the pressure of the airflow is adjusted so that the average spinning speed is 3700 m / min, and the average fineness is 2.1 dtex. The sea-island composite long fiber was spun. The spun sea-island composite long fibers were continuously deposited on the movable net while being sucked from the back of the net. The amount of deposition was adjusted by adjusting the moving speed of the net. And in order to suppress fuzz on the surface, the sea-island type composite long fibers deposited on the net were lightly pressed with a 42 ° C. metal roll. The sea-island composite long fibers were peeled from the net and passed between a lattice-pattern metal roll having a surface temperature of 75 ° C. and a back roll, and hot-pressed at a linear pressure of 200 N / mm. In this way, a long fiber web having a weight per unit area of 34 g / m 2 in which the fibers on the surface were temporarily fused in a lattice shape was obtained.

Next, after spraying an oil agent mixed with an antistatic agent on the surface of the obtained long fiber web, 10 sheets of the long fiber web are overlapped using a cross wrapper device, and the total basis weight is 340 g / m ² . A web was prepared, and a needle breakage oil was sprayed. And the three-dimensional entanglement process was carried out by needle punching the overlap web. Specifically, a 6 barb needle with a distance of 3.2 mm from the needle tip to the first barb was used, and needle punching was performed alternately at 3300 punches / cm ² from both sides of the laminate at a needle depth of 8.3 mm. . The area shrinkage rate by this needle punching treatment was 18%, and the basis weight of the entangled web after needle punching was 415 g / m ² .

The resulting entangled web was densified by a wet heat shrinkage treatment as follows. Specifically, water at 18 ° C. is uniformly sprayed on the entangled web by 10% by mass, and left in a state where no tension is applied for 3 minutes in an atmosphere at a temperature of 70 ° C. and a relative humidity of 95%. The apparent fiber density was improved by heat and heat shrinkage. The area shrinkage rate by the wet heat shrinkage treatment was 45%, the basis weight of the densified entangled web was 750 g / m ² , and the apparent density was 0.52 g / cm ³ . The apparent density was adjusted to 0.60 g / cm ³ by dry-heat roll pressing to further densify the entangled web.

  Next, the densified entangled web was impregnated with a crosslinked non-foamed polyurethane as follows. A densified entangled web was impregnated with a cross-linked aqueous polyurethane emulsion (solid content concentration 30%) mainly composed of polycarbonate / ether polyurethane. And the water | moisture content was dried with the 150 degreeC drying furnace, and also non-foamed polyurethane was bridge | crosslinked. In this way, a polyurethane entangled web composite having a non-foamed polyurethane / entangled web mass ratio of 18/82 was formed.

  Next, the polyurethane entangled web composite is immersed in hot water at 95 ° C. for 20 minutes to extract and remove sea components contained in the sea-island composite long fibers, dried in a drying furnace at 120 ° C., sliced and ground As a result, a sheet having a thickness of about 1.0 mm was obtained.

The apparent density of the fiber entangled body contained in the obtained sheet was 0.53 g / cm ³ , and the mass ratio of non-foamed polyurethane / fiber entangled body was 22/78. The average single fiber fineness of the ultrafine single fiber of the fiber entangled body was 0.08 dtex.

  After the obtained sheet was divided into two in the thickness direction and ground to 0.45 mm, a dry surface-forming layer with a grain having a thickness of 0.11 mm having a silicone-modified polycarbonate polyurethane resin as a skin was formed as a silver surface layer. In this way, an artificial leather layer was obtained. The specific gravity of the obtained artificial leather layer was 0.66. The 30% elongation stress at 150 ° C. was 29 N / 25 mm.

PC / PET made of a 0.20 mm thick PC / PET alloy (PC / PET = 50/50 (mass ratio)) is formed on the surface opposite to the surface on which the silver surface layer of the obtained artificial leather layer is formed. The film was bonded. For PC / PET film, apply urethane adhesive on the surface of PC / PET film at a coating amount of 50 g / m ² (wet), paste it on an artificial leather layer, and press at a pressure of 0.5 MPa. It was laminated by. The formed adhesive layer had a thickness of 55 μm. Thus, the decorating sheet used for manufacture of a preform molding was obtained. The PC / PET film exhibited the SS curve shown in FIG.

  Next, using the obtained decorative sheet, a preform molded body is molded using a mold having a cavity for molding a three-dimensional shape having a trapezoidal cross section having a shape as shown in FIG. did. Specifically, a decorative sheet was placed on the lower mold of a pair of molds at room temperature, the sheet surface was heated to 150 ° C. with infrared rays, and then a pressure of 0.4 MPa was applied from the PC / PET film side. Then, the preform molded object was obtained by cooling. And by trimming, it trimmed in the shape which fits the metal mold | die of subsequent injection insert molding.

  The formability of the obtained preform molded body, the thickness retention before and after molding, and the occurrence of roughness were evaluated according to the following criteria. The results are shown in Table 1.

(Shaping property)
The portion shown in FIG. 9 was observed from the side with an optical microscope and a photograph was taken. Then, the angle θ of the rising portion of the ridge of the ridge of the preform is measured, and the pre-form relative to the angle of the rising portion of the ridge of the ridge of the mold is calculated by the following formula: shaping ratio (%) = (135 / θ) × 100 The ratio of the angle of the rising portion of the base of the mountain of the foam molded body was calculated.

(Thickness retention)
The thickness of the central part of the top surface of the ridge of the preform molded body was measured. And the ratio of the thickness of the center part of the top face of a mountain with respect to the thickness of a decorating sheet was computed.

(Arabi)
The surface state of the preform was determined according to the following criteria.
5th grade: There is almost no appearance.
3rd to 4th grades: A little rough.
1st or 2nd class: Rough appearance appears.

  And the cavity of the insert mold of the injection insert molding machine is such that the artificial leather layer is in contact with the mold surface and the PC / PET film is disposed on the resin flow side of the cavity. Placed in. The mold had a shape along the shape of the preform molded body having a thin portion of 0.8 mm, a two-point gate, and a shape in which the weld line overlapped with the preform molded body.

  Using the injection molding machine as described above, PC resin was injection molded at a molding temperature of 280 ° C. nozzle temperature. The PC / PET film was melted at a nozzle temperature of 280 ° C., but the melt viscosity was higher than that of the PC resin.

  The dimensional stability of the decorative molded body having a leather-like surface thus obtained, the occurrence of wrinkles near the weld line, and the surface property of the leather-like surface were evaluated according to the following criteria. The results are shown in Table 1.

(Dimensional stability)
The end surfaces of the preform molded body and the molded body main body at the end surface of the insert molded body having a shape along the shape of the obtained preform molded body were observed, and the deviation of the end surfaces was determined according to the following criteria.
A: Although there was a dimensional change, there was no variation among individuals, and reproducibility was good.
B: The dimensional change was large, and there was a large variation among individuals and a large deviation or variation within the individuals.

(Occurrence of wrinkles near the weld line)
The occurrence state of wrinkles on the surface of the preform molded body in the weld line portion of the insert molded body having a shape in accordance with the shape of the obtained preform molded body was visually observed and judged according to the following criteria.
A: No wrinkle occurrence B: Wrinkle occurrence

(Surface property of leather-like surface)
The appearance of the leather-like surface of the insert molded body having a shape along the shape of the obtained preform molded body was observed and evaluated according to the following criteria.
A: It has a soft surface and a beautiful surface.
B: Tactile sensation with low flexibility as if the surface was crushed, and has a surface with noticeable wrinkles and roughness.

[Example 2]
In Example 1, instead of using a PC / PET film (PC / PET = 50/50 (mass ratio)), a PC / PET film made of a PC / PET film (PC / PET = 70/30 (mass ratio)) Was used to obtain a preform molded body. Then, using such a preform molded body, a decorative molded body having a leather-like surface was molded and evaluated in the same manner as in Example 1. The PC / PET film was melted at a nozzle temperature of 280 ° C., but the melt viscosity was higher than that of the PC resin. The results are shown in Table 1.

[Example 3]
In Example 1, instead of using a PC / PET film (PC / PET = 50/50 (mass ratio)), a PC / PET film made of a PC / PET film (PC / PET = 40/60 (mass ratio)) Was used to obtain a preform molded body. Then, using such a preform molded body, a decorative molded body having a leather-like surface was molded and evaluated in the same manner as in Example 1. The PC / PET film was melted at a nozzle temperature of 280 ° C., but the melt viscosity was higher than that of the PC resin. The results are shown in Table 1.

[Example 4]
In Example 1, instead of using a PC / PET film (PC / PET = 50/50 (mass ratio)), a PC / ABS film made of a PC / ABS film (PC / ABS = 50/50 (mass ratio)) Was used to obtain a preform molded body. Moreover, in Example 1, instead of performing the injection molding of the PC at the molding temperature of the nozzle temperature of 280 ° C., the ABS resin was injection molded at the molding temperature of the nozzle temperature of 230 ° C. In this way, a decorative molded body having a leather-like surface was molded and evaluated. The PC / ABS film was not melted at a nozzle temperature of 230 ° C., and the elastic modulus (E ′) at a nozzle temperature of 230 ° C. was 0.12 (MPa). The results are shown in Table 1.

[Comparative Example 1]
In Example 1, instead of using a PC / PET film (PC / PET = 50/50 (mass ratio)), a decorative sheet was obtained in the same manner as in Example 1 except that a PC film was used. A foam molding was obtained. Moreover, in Example 1, instead of performing the injection molding of the PC at the molding temperature of the nozzle temperature of 280 ° C., the ABS resin was injection molded at the molding temperature of the nozzle temperature of 230 ° C. In this way, a decorative molded body having a leather-like surface was molded and evaluated. The elastic modulus (E ′) at a nozzle temperature of 230 ° C. was 0.23 (MPa). The results are shown in Table 1.

[Comparative Example 2]
In Example 1, instead of using a PC / PET film (PC / PET = 50/50 (mass ratio)), it has a leather-like surface in the same manner except that a preform molded body was obtained using a PET film. A decorative molded body was molded and evaluated. The PET film was melted at a nozzle temperature of 280 ° C., but the melt viscosity was higher than that of the PC resin.
The results are shown in Table 1.

[Comparative Example 3]
In Example 1, instead of using a PC / PET film (PC / PET = 50/50 (mass ratio)), a decorative sheet was obtained in the same manner as in Example 1 except that an ABS film was used. A foam molding was obtained. Moreover, in Example 1, instead of performing the injection molding of the PC at the molding temperature of the nozzle temperature of 280 ° C., the ABS resin was injection molded at the molding temperature of the nozzle temperature of 230 ° C. In this way, a decorative molded body having a leather-like surface was molded and evaluated. The ABS film was completely melted at a nozzle temperature of 230 ° C. and was mixed with the injected ABS resin in a molten state. The results are shown in Table 1.

[Comparative Example 4]
In Example 1, a decorative sheet was obtained in the same manner as in Example 1 except that the resin film was not laminated, and a preform molded body was obtained. In the same manner, a decorative molded body having a leather-like surface was molded and evaluated. The results are shown in Table 1.

  From Table 1, according to the present invention, the preform molded bodies obtained in Examples 1 to 4 formed using a decorative sheet having a PC / PET film or a PC / ABS film attached to the back surface are all used. The formability was 100%, and extremely accurate shaping was possible. On the other hand, the preform molded body obtained in Comparative Example 1 molded using a decorative sheet having a PC film attached to the back surface had a shapeability of 95%. The preform molded body obtained in Comparative Example 2 molded using a decorative sheet having a PET film attached to the back surface had a formability of 98%. Furthermore, the preform molded body obtained in Comparative Example 3 molded using a decorative sheet having an ABS film attached to the back surface had a formability of 97%. From the said result, it turns out that the decorating sheet which concerns on this invention has the high shaping property of a preform molded object. In addition, when insert molding is performed using the preform molded body obtained in Comparative Example 4 molded using a decorative sheet in which no film is laminated on the back surface, the production stability of the insert molded body is poor, Moreover, the external appearance of the decorative surface was bad.

  INDUSTRIAL APPLICABILITY The present invention is used for insert molding in which the surface of a resin molded body such as a mobile terminal body (smart phone, tablet PC) and accessories such as a case and a cover, a camera grip, a vehicle interior material, and a cosmetic case is decorated with a leather surface. It is done.

DESCRIPTION OF SYMBOLS 1 Decorative resin layer 1a Wrinkle pattern 2 Resin film 3 Silver surface layer 5 Mold 5a Upper mold 5b Lower mold 10,40 Decorative sheet 11 Artificial leather layer 11a Fiber entanglement 11b Polymer elastic body 11c Void 15,50 Injection mold 15a Movable side mold 15b Fixed side mold 15c Spacer plate 15d Cavity 15f Sprue bush 15g, 15h Gate 16 Nozzle 20, 60 Preform molded body 21 Molded body 22 Spru runner 30 Insert molded body 32 Molten resin E End face S 皺

Claims (13)

A decorative sheet comprising a decorative resin layer having a decorated surface and a resin film attached to the back side of the decorative resin layer,
The resin film is a polymer alloy film containing a polycarbonate resin and at least one resin incompatible with the polycarbonate resin and having a softening temperature lower than that of the polycarbonate resin. Sheet.   The decorative sheet according to claim 1, wherein the resin incompatible with the polycarbonate resin includes at least one selected from polyethylene terephthalate resin and acrylonitrile-butadiene-styrene (ABS) resin.   The decorative sheet according to claim 1, wherein the resin incompatible with the polycarbonate resin is a polyethylene terephthalate resin.   The decorative sheet according to claim 1, wherein the resin incompatible with the polycarbonate resin is an ABS resin.   5. The decorative resin layer according to claim 1, comprising a fiber entangled body of ultrafine fibers having an average fineness of 0.9 dtex or less and a crosslinked non-foamed polyurethane impregnated in the fiber entangled body. The decorative sheet as described.   The decorative sheet according to claim 5, wherein the ultrafine fiber includes a polyester having a glass transition temperature (Tg) of 120 ° C. or less.   The decorative sheet according to any one of claims 1 to 4, wherein the decorative resin layer is a layer containing a porous or non-porous elastomer. A preform molded body used as an insert molding material,
A preform molded body obtained by molding the decorative sheet according to any one of claims 1 to 7 into a three-dimensional shape by hot pressing.   A decorative molded body obtained by placing the preform molded body according to claim 8 in a mold and injection-molding a thermoplastic resin. The decorative molded body according to claim 9,
The resin film does not melt at the molding temperature of the injection molding, has an elastic modulus (E ′) higher than the elastic modulus (E ′) of the thermoplastic resin, or higher than the melt viscosity of the thermoplastic resin A decorative molded body having a melt viscosity.   The decorative molded body according to claim 10, wherein an elastic modulus (E ') of the resin film at a molding temperature of the injection molding is 0.05 MPa or more.   A preform molded body obtained by molding the decorative sheet according to claim 2 into a three-dimensional shape by hot pressing is placed in a mold and obtained by injection molding an ABS resin. A decorative molded body.   A preform molded body obtained by molding the decorative sheet according to claim 3 into a three-dimensional shape by hot pressing is disposed in a mold and obtained by injection molding a polycarbonate resin. A decorative molded body.