JP2019038233A - Decorative sheet, structure including decorative sheet and method for producing decorative sheet - Google Patents

Abstract

To provide a decorative sheet capable of yielding high surface quality when attached to a substrate by a vacuum-pressure molding method or an injection molding method.SOLUTION: A decorative sheet, which is attached to a substrate by a vacuum-pressure molding method or an injection molding method, comprises a decorative layer including a printing surface having concavities and convexities, and a smoothing resin layer disposed on the printing surface of the decorative layer or above the decorative layer, wherein the surface of the smoothing resin layer is smoother than the printing surface.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a decorative sheet, a structure including the decorative sheet, and a method for manufacturing the decorative sheet, which are applied to a substrate using a vacuum / pressure forming method or an injection molding method.

  As a method for decorating the surface of a three-dimensional substrate such as an automobile interior or exterior product, a method of attaching a decorative sheet or film to the surface of the substrate is known. A typical decorative sheet application method includes an in-mold injection molding method. In this method, a decorative sheet having a decoration layer or the like formed on a base sheet is directly or after pre-molding, and then set in an injection molding die, and a three-dimensional molded product is injection-molded and simultaneously the decorative sheet is Decorate by integrally bonding to the molded product.

  A vacuum / pressure forming method is also known as a method for attaching a decorative sheet to a substrate. In the vacuum / pressure forming method, a decorative sheet is attached to a base material using a pressure difference while being stretched at room temperature or in a heated atmosphere with respect to a base material previously formed. Since the decorative sheet is affixed to the base material surface of the component by a separate operation from the molding of the base material, the decorative sheet can be affixed to various shapes of the base material with a single vacuum / pressure forming apparatus. In addition, the vacuum / pneumatic molding method can be applied to the three-dimensional shape of the substrate surface with good followability, which is difficult with the in-mold injection molding method. Coating, i.e. entrainment coating, is also possible. As described above, according to the vacuum / pressure forming method, the decorative sheet can be attached to the three-dimensional three-dimensional base material having various complicated shapes with excellent coverage.

  Patent Document 1 (Japanese Patent Application Laid-Open No. 2009-035588) states that “an adhesive film including a base material and an adhesive layer on the base material, wherein the adhesive layer is carboxylated with respect to the total number of repeating units of the polymer (A). A carboxyl group-containing (meth) acrylic polymer having a glass transition temperature (Tg) of 25 ° C. or lower, wherein the ratio of the number of repeating units containing a group is 4.0 to 25%, and (B) the total number of repeating units of the polymer The amino group-containing (meth) acrylic polymer having a glass transition temperature (Tg) of 75 ° C. or higher, wherein the ratio of the number of repeating units containing amino groups is 3.5 to 15%, and component (A) And the component ratio of component (B) is 62:38 to 75:25 by weight.

JP 2009-035588 A

  The decorative layer of the decorative sheet is generally formed using a printing technique such as gravure printing, ink jet printing, offset printing, or screen printing. Since these printing techniques express an image by the density of ink dots, that is, the density of ink dots, minute unevenness due to the difference in the thickness of the printed ink material occurs on the printed surface, and the height of the unevenness and It depends on the color that expresses the density. Gravure printing is widely used for forming a decorative layer because it is simpler than other printing techniques, but the unevenness generated on the printed surface tends to be relatively large.

  The present inventors have used a vacuum / pressure forming method or an injection molding method to deform a decorative sheet, and particularly when affixed to a substrate while being stretched, slight unevenness present on the printed surface propagates to the decorative sheet surface. Then, it has been found that the surface quality of the decorative sheet, for example, sharpness and glossiness, may be impaired. This phenomenon has not been confirmed when the decorative sheet is attached to a flat substrate without deformation.

  The present disclosure provides a decorative sheet that can provide high surface quality when bonded to a substrate by a vacuum / pressure forming method or an injection molding method. The present disclosure also provides a structure including such a decorative sheet, and a method of manufacturing such a decorative sheet.

  According to one embodiment of the present disclosure, there is provided a decorative layer including a printed surface having irregularities, and a smoothing resin layer disposed on the printed surface of the decorative layer or above the decorative layer. Then, a decorative sheet is provided which is adhered to a base material by a vacuum / pressure forming method or an injection molding method, wherein the surface of the smoothing resin layer is smoother than the printing surface.

  According to another embodiment of the present disclosure, a structure including a base material and the decorative sheet applied to the surface of the base material is provided.

  According to still another embodiment of the present disclosure, a step of forming a decorative layer including a printed surface having irregularities, and a smoothing resin layer on the printed surface of the decorative layer or above the decorative layer And a step of forming a surface of the smoothing resin layer smoother than the printed surface, and a method for producing a decorative sheet that is adhered to a substrate by a vacuum / pressure forming method or an injection molding method.

  According to the present disclosure, the smoothing resin layer is disposed on the printed surface having the unevenness of the decorative layer or above the decorative layer, and a smoother surface than the printed surface is provided to the decorative sheet by the smoothing resin layer. By doing so, even when the decorative sheet is bonded to the base material by a vacuum / pressure forming method or an injection molding method, high surface quality such as sharpness and gloss can be realized.

  The above description should not be construed as disclosing all embodiments of the present invention and all advantages related to the present invention.

It is a schematic sectional drawing of the decoration sheet by one embodiment. It is a schematic sectional drawing of the decoration sheet by another embodiment. It is a photograph of the decorative sheet of Example 1 pasted on the curved surface by the vacuum / pressure forming method, and the part surrounded by an ellipse shows the reflection of the indoor fluorescent lamp. It is a photograph of the decoration sheet of the comparative example 1 affixed on the curved surface by the vacuum pressure forming method, and the part enclosed by the ellipse shows the reflection of the indoor fluorescent lamp.

  Hereinafter, the present invention will be described in more detail for the purpose of illustrating representative embodiments of the present invention, but the present invention is not limited to these embodiments.

  In the present disclosure, the “sheet” includes a flexible laminate and a thin laminate called a “film”.

  In the present disclosure, “storage elastic modulus (E ′)” means when the viscoelasticity measurement is performed in a stretch mode with a heating rate of 5.0 ° C./min and a frequency of 10 Hz in a temperature range of −40 ° C. to 200 ° C. Of storage modulus at a specified temperature.

  In the present disclosure, “transparent” means that the total light transmittance in the wavelength range of 400 to 700 nm is about 60% or more, about 80% or more, or about 90% or more. The total light transmittance can be determined based on JIS K 7361-1: 1997 (ISO 13468-1: 1996).

  In the present disclosure, “(meth) acryl” means acryl or methacryl, and “(meth) acrylate” means acrylate or methacrylate.

  In the present disclosure, the “vacuum pressure forming method” is a step of preparing a sheet and an article having a three-dimensional shape, and a step of arranging the sheet and the article in a vacuum chamber having a heating device therein, A sheet separates the internal space of the vacuum chamber into two, the article is disposed in one of the separated internal spaces, a step of heating the sheet by the heating device, and the article is disposed. A step of bringing the internal space and the internal space on the opposite side into a reduced-pressure atmosphere, the internal space in which the article is placed in a reduced-pressure atmosphere, and the internal space on the opposite side in a pressurized atmosphere or a normal-pressure atmosphere. And the sheet is contacted and the article is covered with the sheet. A three-dimensional curved surface coating method (Three-d imensional Overlay Method ("TOM").

  A decorative sheet according to an embodiment of the present disclosure is bonded to a base material by a vacuum / pressure forming method or an injection molding method, and includes a decorative layer including a printed surface having irregularities, and a printed surface of the decorative layer. A smoothing resin layer disposed above or above the decorative layer, and the surface of the smoothing resin layer is smoother than the printed surface.

  FIG. 1 shows a cross-sectional view of a decorative sheet 10 according to an embodiment of the present disclosure. The decorative sheet 10 includes a decorative layer 12 including a printed surface 122 having unevenness, and a smoothing resin layer 14 disposed on the printed surface 122 of the decorative layer 12. The surface 142 is smoother than the printing surface 122 of the decorative layer 12.

  The decorative sheet may further include additional layers such as a support layer, an adhesive layer, a surface layer, a design layer other than the decorative layer, a bonding layer, and a release liner as optional elements, and the number, type, and arrangement of the decorative sheet layers. Etc. are not particularly limited. In FIG. 1, the decorative sheet 10 includes, as optional elements, a support layer 16, an adhesive layer 18 for attaching the decorative sheet to the base material, a transparent surface layer 22 that contributes to surface protection of the decorative sheet, and a decorative sheet. It is shown as including a joining layer 24 that joins the constituent layers (in FIG. 1, the surface layer 22 and the smoothing resin layer 14).

  The decorative layer can be generally formed using a printing technique such as gravure printing, ink jet printing, offset printing, screen printing, and includes a printing surface having unevenness. The decorative layer may be formed by single color printing or multicolor printing. The decorative layer may be continuous or discontinuous. In one embodiment, the decorative layer is composed of a collection of individual ink dots and is discontinuous.

  In one embodiment, the printing surface of the decorative layer is a gravure printing surface. Although gravure printing has high image quality and excellent productivity, the unevenness of the printed surface tends to increase. According to this indication, the above-mentioned advantage of gravure printing can be enjoyed, reducing the influence which the unevenness of a printing surface gives to the surface quality of the decoration sheet after fabrication.

  The shape of the ink dots constituting the printing surface of the decorative layer is not particularly limited. For example, the height is about 0.1 μm or more, about 0.2 μm or more, or about 0.3 μm or more, about 5 μm or less, about 3 μm. Or about 1 μm or less. The density of the ink dots depends on the cell density of the printing plate used or the number of lines per inch. For example, the number of lines is about 18 or more, about 50 or more, or about 100 or more, about 500 or less, about 300 or less, Or about 200 or less. Generally, printing is repeated a plurality of times to form more complicated colors, patterns, and the like. When printing is repeated a plurality of times, plates with different numbers of lines can be used each time.

  In some embodiments, the surface roughness Rz1 of the printing surface of the decorative layer is about 0.2 μm or more, about 0.5 μm or more, or about 0.8 μm or more, about 5 μm or less, about 4 μm or less, or about 3 μm. It is as follows. The unevenness of the printed surface having a surface roughness Rz1 in the above range is fine, but when a decorative sheet not having a smoothing resin layer is attached to a substrate by a vacuum / pressure forming method or an injection molding method, the unevenness becomes a decorative sheet. It propagates to the surface and the surface quality decreases. The surface roughness in the present disclosure is the maximum height roughness measured in accordance with JIS B 0601: 2001.

  The decorative layer may include an adhesive. The decorative layer containing an adhesive can be bonded to another layer constituting the decorative sheet without using a bonding layer. As the adhesive, generally used acrylic type, polyolefin type, polyurethane type, polyester type, rubber type, etc., solvent type, emulsion type, pressure sensitive type, heat sensitive type, thermosetting type or ultraviolet curing type adhesive are used. be able to. The adhesive can be included in the decorative layer using a printing technique such as gravure printing, inkjet printing, offset printing, or screen printing.

  In one embodiment, the adhesive is a thermosensitive adhesive and is at least one thermoplastic resin selected from the group consisting of vinyl chloride-vinyl acetate copolymer, polyurethane, polyester, (meth) acrylic resin, and phenoxy resin. including. In the present disclosure, the “phenoxy resin” means a polyhydroxy polyether having thermoplasticity, which is synthesized using bisphenols and epichlorohydrin, and has a small amount of epoxy group derived from epichlorohydrin in the molecule (for example, terminal). Are also included. For example, the epoxy equivalent of the phenoxy resin is higher than that of a normal epoxy resin, for example, 5,000 or more, 7,000 or more, or 10,000 or more.

  A smoothing resin layer is arrange | positioned on the printing surface of a decorating layer, or the upper direction of a decorating layer, and has a smoother surface than the printing surface of a decorating layer. In the present disclosure, “disposed on” means that the smoothing resin layer is disposed in contact with the printing surface of the decorative layer, and “disposed upward” means “decorative layer” It means that the smoothing resin layer is arranged away from the decorative layer on the surface side when viewed from the side.

  A smoothing resin layer suppresses that the unevenness | corrugation of the printing surface of a decorating layer propagates to the surface of a decoration sheet during vacuum pressure forming or injection molding. Without being bound by any theory, when the decorative sheet is deformed and pasted to the substrate, the elongation of the decorative sheet may be non-uniform in the plane, especially the curvature of the substrate surface. This is prominent where the stress applied to the decorative sheet increases when it is pasted, such as where it is large. Also, when the density of ink dots is high (the color is dark), the decorative sheet is difficult to stretch due to fusion of the ink dots, while when the density of ink dots is low (the color is light), the decorative sheet is easily stretched. Tend to be thinner. In the thinned portion of the decorative sheet, the unevenness of the printing surface of the decorative layer is easily propagated to the surface of the decorative sheet, and the surface quality of the decorative sheet is deteriorated at that portion. The smoothing resin layer of the present disclosure has an appropriate interior so that the printing surface of the decorative layer spreads uniformly in the surface and absorbs unevenness of the printing surface when the decorative sheet is deformed, particularly stretched. By flowing while maintaining the stress, it is considered that the unevenness of the printing surface of the decorative layer is suppressed from propagating to the decorative sheet surface.

  The smoothing resin layer may completely cover the printing surface of the decoration layer, or may cover a part of the printing surface of the decoration layer and not the other part. For example, the smoothing resin layer may be filled in at least a part of the gap between the ink dots on the printing surface of the decorative layer. In one embodiment, the smoothing resin layer is inside the decorative sheet and the surface of the smoothing resin layer is not exposed.

  As a smoothing resin layer, various resins, for example, acrylic resin including polymethyl methacrylate (PMMA) and (meth) acrylic copolymer, polyurethane (PU), polyvinyl chloride (PVC), polycarbonate (PC), acrylonitrile -Polybutadiene such as butadiene-styrene copolymer (ABS), polyethylene (PE), polypropylene (PP), polyester such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), ethylene-acrylic acid copolymer (EAA) , Copolymers such as ethylene-ethyl acrylate copolymer, ethylene-vinyl acetate copolymer (EVA), or a combination thereof can be used. By using a resin layer containing polyurethane or acrylic resin as the smoothing resin layer, it is possible to effectively suppress propagation of unevenness on the printing surface of the decorative layer. More advantageously, the decorative layer comprises polyurethane.

  In one embodiment, the surface roughness Rz2 of the smoothing resin layer is less than the surface roughness Rz1 of the printing surface of the decorative layer. In some embodiments, the surface roughness Rz2 of the smoothing resin layer is about 0.05 μm or more, about 0.1 μm or more, or about 0.15 μm or more, about 1.0 μm or less, about 0.5 μm or less, or It is about 0.3 μm or less. By setting the surface roughness Rz2 of the smoothing resin layer in the above range, the surface quality of the decorative sheet after molding can be improved.

  In some embodiments, the surface roughness Rz2 of the smoothing resin layer is not more than about 0.95 times, not more than about 0.8 times, or not more than about 0.6 times the surface roughness Rz1 of the printed surface of the decorative layer. It is. By setting the surface roughness Rz2 of the smoothing resin layer in the above range, the surface quality of the decorative sheet after molding can be improved.

  In some embodiments, the smoothing resin layer is a coating layer made by applying a resin solution in which a resin and a solvent are mixed to a printing surface. Since the resin solution has fluidity, the unevenness of the printed surface can be filled, and a smoother surface can be formed compared to the surface roughness of the printed surface. Examples of the coating method include gravure printing, screen printing, and casting. The viscosity of the resin solution can be appropriately selected according to the type of coating method.

In some embodiments, the storage modulus of the smoothing resin layer is about 1.0 × 10 ⁶ Pa or more, about 1 at a temperature range of 100 ° C. to 150 ° C. when measured under conditions of a frequency of 10 Hz and a stretch mode. It is 5 × 10 ⁶ Pa or more, or about 2.0 × 10 ⁶ Pa or more, about 1.5 × 10 ⁸ Pa or less, or about 1.3 × 10 ⁸ Pa or less. By setting the storage elastic modulus of the smoothing resin layer within the above range, the smoothing resin layer maintains an appropriate internal stress during molding due to the presence of the smoothing resin layer that fills the unevenness of the printing surface, and decorates. The printed surface of the layer is stretched uniformly in the plane. As a result, the surface roughness of the decorative layer can be further reduced and the smoothness can be increased.

  In some embodiments, the smoothing resin layer is coated, and the thickness after drying is about 2 times or more, about 5 times or more, or about 10 times or more, about 200 times the surface roughness Rz1 of the printing surface of the decorative layer. Hereinafter, it is about 150 times or less, or about 100 times or less. By setting the thickness of the smoothing resin layer within the above range, the surface quality of the decorative sheet after molding can be improved. The thickness of the smoothing resin layer in the present disclosure refers to the thickness of the thickest portion of the smoothing resin layer.

  In some embodiments, the smoothing resin layer has a thickness of about 3 μm or more, about 5 μm or more, or about 10 μm or more, about 100 μm or less, about 75 μm or less, or about 50 μm or less. By setting the thickness of the smoothing resin layer within the above range, the surface quality of the decorative sheet after molding can be improved.

  As an optional support layer, various resins such as acrylic resins including polymethyl methacrylate (PMMA) and (meth) acrylic copolymers, polyurethane (PU), polyvinyl chloride (PVC), polycarbonate (PC ), Polyolefin such as acrylonitrile-butadiene-styrene copolymer (ABS), polyethylene (PE), polypropylene (PP), polyester such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), ethylene-acrylic acid copolymer Copolymers such as (EAA), ethylene-ethyl acrylate copolymer, ethylene-vinyl acetate copolymer (EVA), or combinations thereof can be used. From the viewpoint of strength, impact resistance, etc., polyurethane, polyvinyl chloride, polyethylene terephthalate, acrylonitrile-butadiene-styrene copolymer and polycarbonate can be advantageously used as the support layer. The support layer becomes a support such as a decorative layer, gives uniform elongation during molding, and can also function as a protective layer that more effectively protects the structure from external punctures, impacts, and the like.

  In one embodiment, the support layer is adhesive. In this embodiment, the decorative sheet can be attached to the article without the need for an adhesive layer described later. The support layer having adhesiveness can be formed of the same material as the adhesive layer described later.

  The thickness of the support layer may vary, but is generally about 2 μm or more, about 5 μm or more, or about 10 μm or more from the viewpoint of imparting the above functions to the decoration sheet without adversely affecting the formability of the decoration sheet. About 100 μm or less, about 75 μm or less, or about 50 μm or less. The thickness of the support layer when the support layer is not flat means the thickness of the thinnest portion of the support layer.

In some embodiments, the storage modulus of the support layer is about 1.0 × 10 ⁶ Pa or more, about 1.5 at a temperature range of 100 ° C. to 150 ° C. when measured under conditions of a frequency of 10 Hz and a stretch mode. × 10 ⁶ Pa or more, or about 2.0 × 10 ⁶ Pa or more, about 1.5 × 10 ⁸ Pa or less, or about 1.3 × 10 ⁸ Pa or less. When the storage elastic modulus of the support layer is in the above range, it is possible to impart high-temperature strength and elongation necessary for vacuum / pressure forming or injection molding to the decorative sheet.

  The support layer may be a single layer or may have a multilayer structure. When the support layer has a multi-layer structure, the storage elastic modulus of the support layer means one value observed for the entire multi-layer structure in which the storage elastic moduli of the individual layers are combined.

  The decorative sheet may further include an adhesive layer for attaching the decorative sheet to the substrate. As the adhesive layer, a solvent type, emulsion type, pressure sensitive type, heat sensitive type, thermosetting type or ultraviolet curable type adhesive such as acrylic type, polyolefin type, polyurethane type, polyester type, rubber type and the like which are generally used is used. Acrylic adhesives and thermosetting polyurethane adhesives can be advantageously used. As the adhesive layer, a film obtained by forming thermoplastic polyurethane into a film by molding, extrusion, stretching, or the like can be used.

  The thickness of the adhesive layer can generally be about 5 μm or more, about 10 μm or more, or about 20 μm or more, about 200 μm or less, about 100 μm or less, or about 80 μm or less.

  Any suitable release liner may be used to protect the adhesive layer. Exemplary release liners include those made from paper (eg, kraft paper) or polymeric materials (eg, polyolefins such as polyethylene or polypropylene, polyesters such as ethylene vinyl acetate, polyurethane, polyethylene terephthalate, etc.). The release liner may be coated with a release agent such as a silicone-containing material or a fluorocarbon-containing material as necessary.

  The thickness of the release liner is generally about 5 μm or more, about 15 μm or more, or about 25 μm or more, about 300 μm or less, about 200 μm or less, or about 150 μm or less.

  As an optional surface layer, various resins such as acrylic resins including polymethyl methacrylate (PMMA) and (meth) acrylic copolymers, polyurethane (PU), ethylene-tetrafluoroethylene copolymer (ETFE). ), Polyvinylidene fluoride (PVDF), fluororesin such as methyl methacrylate-vinylidene fluoride copolymer (PMMA / PVDF), polyvinyl chloride (PVC), polycarbonate (PC), polyethylene (PE), polypropylene (PP) Polyolefin such as polyethylene, polyester such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), ethylene-acrylic acid copolymer (EAA) and its ionomer, ethylene-ethyl acrylate copolymer, ethylene-vinyl acetate copolymer EVA) copolymers, such as, or a combination thereof can be used.

  Acrylic resin, polyurethane, fluororesin, and polyvinyl chloride are preferable because of their excellent weather resistance, and they have excellent scratch resistance, and they have a low environmental impact when incinerated or landfilled as waste. Resins and polyurethane are more preferred.

  The surface layer may contain isosorbide-based polycarbonate. The surface layer containing the isosorbide-based polycarbonate can be formed by applying a solution obtained by dissolving the isosorbide-based polycarbonate in a solvent onto a base material by casting and drying. The surface layer thus formed has high flatness and can further improve the surface quality of the decorative sheet.

  The surface layer may have a multilayer structure. For example, the surface layer may be a laminate of films formed from the resin, or may be a multilayer coating of the resin.

  The thickness of the surface layer can vary, but is generally about 1 μm or more, about 5 μm or more, or about 10 μm or more, about 150 μm or less, about 100 μm or less, or about 80 μm or less. When the decorative sheet is applied to a substrate having a complicated shape, it is advantageous that the surface layer is thin from the viewpoint of shape followability, for example, about 100 μm or less, or about 80 μm or less. On the other hand, when high light resistance and / or weather resistance is imparted to the structure, it is advantageous that the surface layer is thicker, for example, about 5 μm or more, or about 10 μm or more.

  If necessary, the surface layer may be made of benzotriazole, an ultraviolet absorber such as Tinuvin (trademark) 400 (manufactured by BASF), or a hindered amine light stabilizer (HALS) such as Tinuvin (trademark) 292 (manufactured by BASF) May be included. Effective use of UV absorbers, hindered amine light stabilizers, etc., for discoloration, fading, degradation, etc. of organic pigments with relatively high sensitivity to light such as ultraviolet rays, especially in coloring layers Can be prevented. The surface layer may include a hard coat material, a gloss imparting agent, and the like, and may have an additional hard coat layer.

  The surface layer is generally transparent. In some embodiments, the total light transmittance of the surface layer is greater than about 85%, or greater than about 90% in the wavelength range of 400-700 nm. In order to provide the desired appearance, the surface layer may be wholly or partially translucent or partially opaque.

  A bonding layer may be used to bond the above layers. Commonly used acrylic, polyolefin, polyurethane, polyester, rubber, etc. solvent-type, emulsion-type, pressure-sensitive type, heat-sensitive type, thermosetting type, or UV-curable type adhesives are used as the bonding layer. be able to. The thickness of the bonding layer can generally be about 0.05 μm or more, about 0.5 μm or more, or about 5 μm or more, about 100 μm or less, about 50 μm or less, or about 20 μm or less.

  The decorative sheet may include a design layer other than the decorative layer. Examples of the design layer include a color layer exhibiting a paint color, a metal color, a relief (relief pattern) layer, and a glitter layer. The design layer may have a multilayer structure, and may have the above bonding layer between layers.

  Examples of color layers include inorganic pigments such as titanium oxide, carbon black, yellow lead, yellow iron oxide, red iron oxide, phthalocyanine pigments such as phthalocyanine blue and phthalocyanine green, azo lake pigments, indigo pigments, and perinone pigments. Pigments, perylene pigments, quinophthalone pigments, dioxazine pigments, organic pigments such as quinacridone pigments such as quinacridone red, aluminum flakes, evaporated aluminum flakes, metal oxide coated aluminum flakes, colored aluminum flakes such as colored aluminum flakes, oxidation A pigment in which a pearl glitter material such as flake mica coated with a metal oxide such as titanium or iron oxide or a synthetic mica is dispersed in a binder resin such as an acrylic resin or polyurethane can be used.

  As the relief layer, a thermoplastic resin film having a concavo-convex shape on the surface by a conventionally known method such as embossing, scratching, laser processing, dry etching processing, or hot press processing can be used. A relief layer may also be formed by applying a thermosetting or radiation curable resin such as a curable acrylic resin on a release film having a concavo-convex shape, curing by heating or radiation irradiation, and removing the release film. it can. The thermoplastic resin, thermosetting resin and radiation curable resin used for the relief layer are not particularly limited, but are not limited to polyester resins such as fluorine resins, PET, PEN, acrylic resins, polyethylene, polypropylene, thermoplastic elastomers, polycarbonates. Polyamide, ABS resin, acrylonitrile-styrene resin, polystyrene, vinyl chloride, polyurethane and the like can be used.

  The thickness of the color layer and the relief layer can vary and can generally be about 5 μm or more, about 10 μm or more, or about 20 μm or more, about 500 μm or less, about 300 μm or less, or about 200 μm or less.

  As a bright layer, a metal such as aluminum, nickel, gold, platinum, chromium, iron, copper, tin, indium, silver, titanium, lead, zinc, germanium, or an alloy or compound thereof on the other layer of the decorative sheet In addition, a thin film formed by vacuum deposition, sputtering, ion plating, plating, or the like can be used. Since the bright layer has high gloss, it is preferably used for a chrome plating substitute film. In this case, the thickness of the metal layer can be about 5 nm or more, about 10 nm or more, or about 20 nm or more, about 10 μm or less, about 5 μm or less, or about 2 μm or less.

  A bright layer may be incorporated into the support layer. FIG. 2 shows a cross-sectional view of a decorative sheet 10 according to another embodiment of the present disclosure. In the decorative sheet 10 of FIG. 2, the support layer 16 is a laminate of the first support layer 162, the bright layer 26, and the second support layer 164, and the first support layer 162 and the second support layer 164 are embossed inside. The image of the decorative sheet is visually changed by the glitter layer 26 provided on the relief surface.

  Such a support layer 16 has a relief surface by, for example, pressing a mold having an embossed pattern on a flat layer formed of a material constituting the first support layer 162 while heating as necessary. The first support layer 162 is formed, a thin metal film is deposited thereon to form the glitter layer 26, and a composition containing the material constituting the second support layer 164 is applied thereon and dried or cured. Can be formed.

  The pattern or pattern on the relief surface may be regular or irregular, and is not particularly limited, for example, line, wood grain, sand grain, stone grain, cloth grain, satin, leather, mat, hairline, spin, Can be letters, symbols, geometric figures, etc. When the relief surface is formed by a groove, the width of the groove is generally in the range of about 5 μm or more, or about 10 μm or more, about 1 mm or less, or about 100 μm or less.

  The depth of the relief surface is determined as the height difference from the convex top to the continuous concave bottom. The depth of the relief surface may be uniform across the relief surface or may have various values. The depth of the relief surface is generally in the range of about 5 μm or more, or about 10 μm or more, about 100 μm or less, or about 50 μm or less.

  The surface layer, the support layer, the adhesive layer, and / or the bonding layer may contain the same coloring materials as those described for the design layer, such as inorganic pigments, organic pigments, aluminum glitter materials, and pearl glitter materials.

  The manufacturing method of the decoration sheet of one embodiment forms a smoothing resin layer on the upper side of the process of forming the decoration layer containing the printing surface which has an unevenness, the printing surface of the decoration layer, or the decoration layer, Forming a smoothing resin layer surface smoother than the printing surface. The formation of the decoration layer and the smoothing resin layer is as described above.

  As for the other layers, for example, those formed into a film by extrusion, stretching, etc. can be used, and these layers can be laminated with or without using a bonding layer. The resin composition is coated on another layer or liner by knife coating, bar coating, blade coating, doctor coating, roll coating, cast coating, etc., and heated or dried or cured as necessary, thereby forming each layer. It can also be formed. For example, a decorative sheet can be produced by forming each layer on a liner such as a PET film whose surface has been subjected to a release treatment, and laminating these layers. Alternatively, each layer can be sequentially laminated on a single liner by repeating the coating step and, if necessary, the curing step. A decorative sheet can be formed by extruding the material of each layer in multiple layers.

  The thickness of the decorative sheet is generally about 25 μm or more, about 50 μm or more, or about 100 μm or more, about 2 mm or less, about 1 mm or less, or about 500 μm or less. By setting the thickness of the decorative sheet within the above range, the decorative sheet can sufficiently follow a substrate having a complicated shape, and a structure having an excellent appearance can be provided.

  In order to evaluate the sharpness of the surface of the decorative sheet, it is more suitable to use an index of the waviness surface roughness Wz obtained by capturing the surface state by the surface waviness, not the surface roughness Rz of the decorative sheet surface. . For example, the waviness surface roughness Wza of the decorative sheet before molding is generally about 0.1 μm or more, about 0.3 μm or more, or about 0.5 μm or more, about 5 μm or less, about 3 μm or less, or about 1 μm or less. In some embodiments, since the unevenness of the printed surface of the decorative layer is suppressed from being propagated to the decorative sheet surface, the waviness surface roughness Wzb after molding of the decorative sheet is approximately the waviness surface roughness Wza before molding. In addition to this, the decorative sheet surface is smoothed by deformation during molding, so that it is smaller than that, for example, about 1.2 times or less, about 1 time or less, or about 0.8 times or less.

  The scratch resistance of the decorative sheet can be evaluated by pencil hardness according to JIS K5600-5-4: 1999. The decorative sheet according to one embodiment has a pencil hardness of 2B or more when the decorative sheet is fixed on the glass plate with the adhesive layer facing the surface of the glass plate and the surface layer is scratched at a speed of 600 mm / min. The pencil hardness can be 6B or more, 5B or more, 4B or more, or 3B or more.

The maximum area elongation of the decorative sheet after molding is generally about 50% or more, about 100% or more, or about 200% or more, about 1000% or less, about 500% or less, or about 300% or less. The area elongation rate is the area elongation rate (%) = (B−A) / A (A: area before molding of a portion with a decorative sheet, B: area after molding of a portion corresponding to A of the decorative sheet). Defined. For example, if the area of a part of the decorative sheet is 100 cm ² before molding and the part becomes 250 cm ^{2 on} the surface of the article after molding, it is 150%. The maximum area elongation rate refers to the value of the highest area elongation rate among the decorative sheets on the entire surface of the molded product. When a flat film is pasted on an article having a three-dimensional shape by a vacuum / pressure forming method, for example, the portion where the film first hits the article is hardly stretched and the area elongation is almost 0%, and the end portion to be pasted last Then, the area elongation rate varies greatly depending on the location, for example, the area elongation rate is 200% or more. The portion where the film is stretched the most is not the average area elongation rate of the entire molded product, but the portion that is stretched the most, because whether or not a failure such as non-tracking to the article or tearing of the film occurs is determined. The area elongation rate, that is, the maximum area elongation rate is a substantial indicator of the pass / fail of the molded product. The maximum area elongation rate is obtained by, for example, printing a 1 mm square on the entire surface of the decorative sheet before molding and measuring the area change after molding, or measuring the thickness of the decorative sheet before and after molding. I can confirm.

  According to one embodiment, a structure is provided that includes a substrate and a decorative sheet applied to the surface of the substrate. The substrate may be made of a variety of materials, such as polypropylene, polycarbonate, acrylonitrile-butadiene-styrene copolymers, or mixtures or blends thereof, and materials having a variety of planar and three-dimensional shapes can be used. . By applying the decorative sheet to the base material by a vacuum / pressure forming method or an injection molding method, a structure in which the decorative sheet and the base material are integrated can be formed. Vacuum / pressure forming and injection molding can be performed by a conventionally known method.

  The decorative sheet of the present disclosure can be used for decoration of automobile parts, home appliances, vehicles such as railways, building materials, etc., and particularly interior and exterior parts of automobiles having high gloss or fine patterns, home appliances, etc. It can be used advantageously for decoration.

  In the following examples, specific embodiments of the present disclosure are illustrated, but the present invention is not limited thereto. All parts and percentages are by weight unless otherwise specified.

  The reagents and raw materials used in this example are shown in Table 1 below.

[Example 1]
(1) A D-6260 polyurethane solution was applied onto a G2PET film and dried at 80 ° C. for 5 minutes and further at 100 ° C. for 5 minutes to form a 25 μm thick polyurethane layer.

  (2) Using an embossed cylinder having a hairline pattern design, the shape of the hairline pattern was transferred to the surface of the polyurethane layer formed in (1) at a cylinder temperature of 190 ° C.

(3) Tin was deposited on the embossed surface of the polyurethane layer under the following conditions (OD value 1.1 to 1.2).
Equipment: Vacuum evaporation equipment EX-400 (ULVAC, Inc., Chigasaki, Kanagawa, Japan)
Target metal evaporation energy source: electron beam Tin deposition layer thickness: 430 Å Tin deposition layer deposition rate: 5 Å / sec

  (4) The D-6260 polyurethane solution was applied to the embossed surface of the polyurethane layer and dried under the same conditions as in (1) to fill the unevenness of the embossed surface of the polyurethane layer.

(5) Acrylic adhesive layer G2PET which has been subjected to release treatment with an acrylic adhesive solution obtained by mixing 50 parts by mass of SK1506BHE, 17 parts by mass of YM-5 and 33 parts by mass of methyl isobutyl ketone (MIBK) It was coated on a film and dried at 80 ° C. for 5 minutes and further at 120 ° C. for 5 minutes to form a 40 μm thick acrylic adhesive layer.

  (6) The acrylic adhesive layer formed in (5) was heat-laminated at 50 ° C. on the embossed surface of the polyurethane layer in which the irregularities were filled in (4).

  (7) A decorative layer was formed on the G2PET film by gravure printing in the order of one plate of polyurethane adhesive containing phenoxy resin, five plates of ink and one plate of polyurethane adhesive containing phenoxy resin. A D-6260 polyurethane solution was applied thereon in a coating amount so that the dry thickness on a flat surface was 10 μm, and dried under the same conditions as in (1) to form a smoothing resin layer.

  (8) After removing the G2PET film on the polyurethane layer of the laminate formed in (6), heat lamination was performed at 120 ° C. so that the decorative layer coated with polyurethane in (7) and the polyurethane layer face each other.

  (9) The G2PET film on the decorative layer was removed, and a S014G acrylic film as a surface layer member was heat laminated at 120 ° C. on the decorative layer to obtain a decorative sheet of Example 1.

[Comparative Example 1]
(1) A D-6260 polyurethane solution was applied onto a G2PET film and dried at 80 ° C. for 5 minutes and further at 100 ° C. for 5 minutes to form a 25 μm thick polyurethane layer.

  (2) Using an embossed cylinder having a hairline pattern design, the shape of the hairline pattern was transferred to the surface of the polyurethane layer formed in (1) at a cylinder temperature of 190 ° C.

(3) Tin was deposited on the embossed surface of the polyurethane layer under the following conditions (OD value 1.1 to 1.2).
Apparatus: Vacuum deposition apparatus EX-400 (ULVAC, Inc.)
Energy source for evaporating the target metal: Electron beam Tin deposition layer thickness: 430 Å Tin deposition layer deposition rate: 5 Å / sec

  (4) The D-6260 polyurethane solution was applied to the embossed surface of the polyurethane layer and dried under the same conditions as in (1) to fill the unevenness of the embossed surface of the polyurethane layer.

(5) Acrylic adhesive layer G2PET which has been subjected to release treatment with an acrylic adhesive solution obtained by mixing 50 parts by mass of SK1506BHE, 17 parts by mass of YM-5 and 33 parts by mass of methyl isobutyl ketone (MIBK) It was coated on a film and dried at 80 ° C. for 5 minutes and further at 120 ° C. for 5 minutes to form a 40 μm thick acrylic adhesive layer.

  (6) The acrylic adhesive layer formed in (5) was heat-laminated at 50 ° C. on the embossed surface of the polyurethane layer in which the irregularities were filled in (4).

  (7) The decorative layer was formed on the G2PET film by gravure printing in the order of 1 plate of adhesive, 5 plates of ink, and 1 plate of adhesive.

  (8) After removing the G2PET film on the polyurethane layer of the laminate formed in (6), the laminate was heat laminated at 120 ° C. so that the decorative layer and the polyurethane layer of (7) face each other.

  (9) The G2PET film on the decorative layer was removed, and a S014G acrylic film as a surface layer member was heat laminated at 120 ° C. on the decorative layer to obtain a decorative sheet of Comparative Example 1.

[Measurement of surface roughness of decorative layer and smoothing resin layer]
Using the surface roughness measuring machine Mitutoyo SURFTEST SV-3100 (Mitutoyo Co., Ltd., Kawasaki City, Kanagawa, Japan), the D-6260 polyurethane solution was applied on a smooth surface for the decorative layer formed in (7) of Example 1. The coating thickness was 10 μm, and the surface roughness Rz (μm) before and after coating was measured. The surface roughness before coating corresponds to the surface roughness Rz1 of the printing surface of the decorative layer, and the surface roughness after coating corresponds to the surface roughness Rz2 of the smoothing resin layer. The results are shown in Table 2. In addition, the coating direction was set to Machine Direction (MD) with respect to the sheet, and the direction orthogonal to this direction was set to Cross Direction (CD), and the surface roughness was measured in each direction. The improvement rate in Table 2 is (Rz1-Rz2) / Rz1 (%).

[Viscoelastic properties of smoothing resin layer]
The viscoelastic properties of the smoothing resin layer were measured by the following procedure. A D-6260 polyurethane solution was applied onto a G2PET film and dried at 80 ° C. for 5 minutes and further at 100 ° C. for 5 minutes to form a 25 μm-thick polyurethane layer as a smoothing resin layer. Using a dynamic viscoelasticity measuring device ARES (manufactured by TA Instruments Japan Co., Ltd., Shinagawa-ku, Tokyo, Japan), in a temperature range of −40 ° C. to 200 ° C., the rate of temperature increase is 5.0 ° C. / When the measurement was performed in a stretch mode with a frequency of 10 Hz, it was 8.55 × 10 ⁷ Pa at 100 ° C., 6.79 × 10 ⁶ Pa at 150 ° C., and in a temperature range of 100 ° C. to 150 ° C. in the stretch mode. The storage elastic modulus was in the range of 1 × 10 ⁶ Pa to 1.5 × 10 ⁸ Pa.

[Vacuum forming]
Using a double-sided vacuum molding machine (Fuse Vacuum Co., Ltd., Habikino City, Osaka, Japan), the decorative sheets of Example 1 and Comparative Example 1 were pasted on a plastic substrate (flat plate and kamaboko shape) by vacuum / pressure forming at 145 ° C. I attached.

[Vividness]
The reflection state of the indoor fluorescent lamp on the decorative sheet surface was compared. The results are shown as photographs in FIG. 3 (Example 1) and FIG. 4 (Comparative Example 1). In these drawings, the reflection of the fluorescent lamp can be visually recognized in a portion surrounded by an ellipse. In the decorative sheet of Example 1, the reflection of the fluorescent lamp is clear and the surface of the decorative sheet is smooth. In the decorative sheet of Comparative Example 1, the reflection of the fluorescent lamp is unclear, and the light is reflected in the vicinity in the vicinity thereof, so that it is inferred that the decorative sheet surface is uneven.

[Measurement of surface roughness of decorative sheet]
As an index for objectively evaluating the sharpness of the decorative sheet surface, the wavy surface roughness Wza and Wzb before and after vacuum / pressure forming were measured in the MD and CD directions for the decorative sheets of Example 1 and Comparative Example 1. . The results are shown in Table 3 together with visual clarity. Table 4 shows the values of the surface roughness Ra before and after vacuum / pressure forming, which were measured together with the undulating surface roughness Wz. The waviness improvement rate in Table 3 is (Wza-Wzb) / Wza (%), and the plane improvement rate in Table 4 is (Raa-Rab) / Raa (%).

  In the decorative sheet of Comparative Example 1, the surface roughness is increased after molding, particularly when the decorative sheet is stretched and attached to a curved surface. Therefore, in Comparative Example 1 without the smoothing resin layer, the unevenness of the printing surface of the decorative layer propagates to the surface of the decorative sheet during molding, and the decorative sheet is stretched and thinned during molding. It is suggested that the surface roughness of the sheet is increased.

DESCRIPTION OF SYMBOLS 10 Decorative sheet 12 Decorating layer 122 Printing surface 14 Smoothing resin layer 142 Surface of smoothing resin layer 16 Support layer 162 First support layer 164 Second support layer 18 Adhesive layer 22 Surface layer 24 Bonding layer 26 Bright layer

Claims (7)

A decorative layer including a printed surface having irregularities;
A vacuum pressure forming method, comprising: a smoothing resin layer disposed on the printing surface of the decoration layer or above the decoration layer, wherein the surface of the smoothing resin layer is smoother than the printing surface. Or the decoration sheet | seat adhere | attached on a base material by the injection molding method.   The decorative sheet according to claim 1, wherein a surface roughness Rz1 of the printing surface of the decorative layer is 0.2 µm or more, and a surface roughness Rz2 of the smoothing resin layer is 0.95 times or less of Rz1. .   The decorative sheet according to claim 1, wherein the printing surface is a gravure printing surface. The said smoothing resin layer has a storage elastic modulus of 1 × 10 ⁶ Pa to 1.5 × 10 ⁸ Pa in a temperature range of 100 ° C. to 150 ° C. when measured under conditions of a frequency of 10 Hz and a stretch mode. The decorative sheet according to any one of 1 to 3.   The said smoothing resin layer is a decoration sheet as described in any one of Claims 1-4 containing a polyurethane or an acrylic resin.   The structure containing a base material and the decoration sheet as described in any one of Claims 1-5 applied to the surface of the said base material. Forming a decorative layer including a printed surface having irregularities;
Forming a smoothing resin layer on the printed surface of the decorative layer or above the decorative layer, and forming a surface of the smoothed resin layer smoother than the printed surface,
A method for producing a decorative sheet, which is adhered to a substrate by a vacuum / pressure forming method or an injection molding method.