JP6134663B2 - Article surface decorative sheet, article surface decorative patch, decorative molded body, and method for producing article surface decorative sheet - Google Patents

Description

  The present invention relates to an article surface decorating sheet or the like for imparting a leather-like appearance having an embossed portion such as a textured pattern to the surface of an article.

  A decorative insert molded body having a leather-like appearance is known as an exterior member of a cellular phone, a mobile device, a home appliance, an interior part of a vehicle, an airplane, or the like, a building material, or furniture.

  For example, Patent Document 1 below includes a base material layer obtained by impregnating a first polyurethane with a nonwoven fabric in which a fiber bundle of polyester ultrafine fibers is entangled, and a second polyurethane formed on the surface of the base material layer. A silver surface layer, the thickness of the base material layer is 0.5 mm or less, the silver surface layer accounts for 10 to 40% of the total thickness, and the direction in which the nonwoven fabric is most stretched is the MD direction, MD Disclosed is a preform molding sheet in which the ratio of 20% tensile stress in the MD direction to the TD direction (MD / TD) is 1.9 to 2.5 when the direction perpendicular to the surface direction is the TD direction. . Then, a preform molded body that is subjected to injection insert molding is molded using such a preform molding sheet, and insert molding is performed using the obtained preform molded body, thereby adding a leather-like surface. Disclosed is a decorative insert molded body. Moreover, patent document 1 is disclosing that an embossing pattern may be formed in the surface of a silver surface layer by using an embossing machine.

  Conventionally, when an embossed part such as a textured pattern is to be applied to the silver surface layer, there has been the following problem.

  Examples of a method for forming an embossed portion such as a texture pattern on a sheet having a silver surface layer include the following methods. First, after forming a coating film of a resin liquid containing a polymer elastic body such as polyurethane on the surface of a release paper having a textured pattern, the silver surface layer is formed by solidifying the polymer elastic body. And after adhere | attaching a silver surface layer to a base material layer, the sheet | seat in which the silver surface layer which has a wrinkle pattern was formed in the surface of a base material layer is obtained by peeling a release paper. However, in the case of such a method, when an embossed pattern with a large height difference is to be formed, the silver surface layer has to be thickened.

  The second method is to form a smooth silver surface layer by solidifying the polymer elastic body after forming a coating film of a resin liquid containing the polymer elastic body on the smooth release paper surface. And after adhering the formed silver surface layer to a base material layer, the sheet | seat which has a smooth surface silver surface layer laminated | stacked on the base material layer is formed by peeling a release paper. And it heat embosses to the sheet | seat which has a smooth silver surface layer using the embossing roll which has a wrinkle pattern. However, when hot embossing is performed using an embossing roll having an embossed pattern with a large difference in height, there is a problem that the embossed pattern is difficult to be accurately transferred.

  By the way, a technique for accurately transferring a wrinkle pattern on a surface layer of a leather-like sheet used for a basketball fabric, a clothing fabric, a shoe fabric, or the like is known. For example, in Patent Document 2 below, a polymer mainly composed of polyurethane that can be softened or melt-molded at a lower temperature than the constituent materials of the other layers is formed on the surface layer constituting the intermediate portion between the fibrous base layer and the finishing layer. Disclosed is a leather-like sheet that can be sharply shaped by use. Specifically, at least one surface of the fibrous base layer has a softening molding temperature of 130 to 185 ° C. and a softening molding temperature that is at least 30 ° C. lower than the softening temperature of the main fibers and the main polymer constituting the base layer. A sheet obtained by laminating a surface layer composed of a polyurethane-based polymer having a polyurethane and a finishing layer composed of a polymer having a softening molding temperature at least 30 ° C. higher than the polymer constituting the surface layer Is embossed at a temperature at which the polymer constituting the surface layer is softened and molded so that the polymer constituting the finishing layer is not fluidly deformed.

JP 2013-209780 A Japanese Patent Laid-Open No. 02-061181

  For example, in the case of an article surface decorating sheet that is used by adhering to the surface of a molded body like a seal with an adhesive or an adhesive, a thinner thickness is required to accurately bond to the curved surface of the molded body. Cited Document 2 discloses forming a resin layer mainly composed of polyurethane having a softening temperature of 130 to 185 ° C. having a thickness of 100 to 2000 μm as a sufficient thickness for providing unevenness by hot embossing. ing. However, in the technique disclosed in the cited document 2, since unevenness is given only to the resin layer mainly composed of polyurethane having a softening molding temperature of 130 to 185 ° C., for example, unevenness with an elevation difference of 150 μm or more is accurately detected. However, there is a problem that the resin layer becomes inevitably thick.

  An object of the present invention is to provide an article surface decorating sheet having a leather-like appearance, in which an embossed portion such as a texture pattern having a large height difference is accurately transferred while maintaining thinness.

  One aspect of the present invention is an article surface decorating sheet having an embossed portion, which bonds a nonwoven fabric substrate, a surface layer of 1 to 100 μm mainly composed of a polymer elastic body, and the nonwoven fabric substrate and the surface layer. An intermediate layer having a thickness of 10 to 150 μm including a hot melt adhesive, and the nonwoven fabric base material includes an entanglement of fiber bundles of ultrafine fibers having a fineness of 0.8 dtex or less, at least in the embossed section. It is the article | item surface decorating sheet whose average value of the distance between fiber bundles is 0-10 micrometers. In the article surface decorative sheet having such a configuration, the intermediate layer having a thickness of 10 to 150 μm is mainly composed of a hot-melt adhesive, and thus has excellent thermal transferability. Moreover, when the embossed part with a large height difference is formed, the uneven pattern is transferred not only to the surface layer and the intermediate layer but also to the nonwoven fabric substrate. In that case, the nonwoven fabric base material is densified so that the average value of the distance between the fiber bundles in the cross section in the thickness direction is 0 to 10 μm.

Furthermore, hot-melt adhesive preferably has a 0 to 30 ° C. softening temperature higher than the glass transition temperature of the microfine fibers (T _g). In such a case, because the softening temperature T _g of the hot-melt adhesive of the ultrafine fibers is closer, by heat embossing, clearly uneven pattern on the intermediate layer and the nonwoven fabric base material is transferred. Further, when the microfine fibers comprise a modified polyester having a T _g of 100 to 120 ° C., the ultrafine fibers can be easily stretched by a general embossing.

  Further, the height difference between the embossed portion and the non-embossed portion is larger than the total thickness of the surface layer and the intermediate layer. Specifically, the height difference is the thickness of the surface layer and the intermediate layer. When it is 1.1 times or more of the total, or when the height difference is 150 μm or more, the uneven pattern is more easily transferred to the nonwoven fabric substrate, and the contour is accurately expressed.

Moreover, the ratio of the thickness when the article surface decorative sheet was measured with a constant pressure thickness measuring device set to 240 gf / cm ² with respect to the thickness measured with a scanning microscope (SEM) at least in the embossed portion was 90%. In the case described above, it can be said that even the unevenness having a large difference in height is accurately transferred.

  In addition, when the nonwoven fabric substrate contains 5 to 40% by mass of a crosslinked non-porous polymer elastic body, the nonwoven fabric substrate is sufficiently coated with a pressure at the time of hot embossing. This is preferable from the viewpoint of increasing the density.

  Moreover, when the thickness of an article surface decoration sheet is 300-1000 micrometers, when decorating the surface of an article | item containing a curved surface, it is preferably used as a sheet | seat correctly bonded.

  In addition, another aspect of the present invention includes any one of the above article surface decorating sheets and an adhesive layer or an adhesive layer (hereinafter, collectively referred to as an adhesive layer) laminated on the back surface side. This is an article surface decorative patch.

  Another aspect of the present invention is a decorative molded body formed by adhering any of the above article surface decorative sheets to the surface of a molded body.

Another aspect of the present invention is a method for producing an article surface decorating sheet comprising the following steps.
(1) T _g and the nonwoven fabric substrate comprising entangled body of fiber bundle following ultrafine fiber fineness 0.8dtex containing modified polyester is 100 to 120 ° C., the surface layer having a thickness of 1~100μm comprising elastic polymer And a thermal transfer sheet comprising a hot melt adhesive having a softening temperature of 0 to 30 ° C. higher than the T _g and adhering the nonwoven fabric substrate and the surface layer, and having a thickness of 10 to 150 μm. And (2) heat embossing the heat-transferred sheet so that the average value of the distance between the fiber bundles in the cross section in the thickness direction at least in the embossed portion is 0 to 10 μm. Step (1) includes (1a) a step of preparing a nonwoven fabric substrate, (1b) a step of forming a surface layer having a thickness of 1 to 50 μm mainly composed of a polymer elastic body on the surface of the release paper, (1c) forming a coating film of a hot-melt adhesive solution on the surface layer formed on the surface of the release paper so that the thickness upon drying is 10 to 150 μm; and (1d) Forming a thermal transfer sheet by pressing the nonwoven fabric substrate, adhering the nonwoven fabric substrate and the hot-melt adhesive while removing the solvent in the coating film, and removing the release paper. preferable. Moreover, it is preferable that the surface temperature of the embossing type | mold used for hot embossing is 10-30 degreeC higher than the softening temperature of a hot-melt-type adhesive agent.

  ADVANTAGE OF THE INVENTION According to this invention, the surface decoration sheet | seat which has the leather-like external appearance by which the embossed part like a wrinkle pattern with a large elevation difference was correctly transcribe | transferred by hot embossing, maintaining thinness is obtained.

FIG. 1 is a schematic cross-sectional view of a decorative molded body 40 obtained using the article surface decorative sheet 20 of the present embodiment. FIG. 2 is a schematic cross-sectional view of the thermal transfer sheet 10 of the present embodiment. 3 is an SEM image of an embossed portion of the article surface decorating sheet of Example 1. FIG.

  An embodiment of an article surface decorative sheet, an article surface decorative patch, and a decorative molded body according to the present invention will be described.

  FIG. 1 shows an article formed by adhering an article surface decorative sheet 20 to the surface of a molded body 31 via a pressure-sensitive adhesive layer or an adhesive layer (hereinafter collectively referred to as an adhesive layer) 14. FIG. 1A is a schematic view of a decorative molded body 40, FIG. 1A is a top view, and FIG. 1B is a schematic view of a II ′ cross section of FIG. The article surface decorating sheet 20 is a non-woven fabric substrate 1, a surface layer 2 having a thickness of 1 to 100 μm including a polymer elastic body, and a hot-melt adhesive disposed between the nonwoven fabric substrate 1 and the surface layer 2. And an intermediate layer 3 having a thickness of 10 to 150 μm containing the agent. Further, the article surface decorating sheet 20 has an embossed portion H that forms a concavo-convex pattern transferred by hot embossing. The article surface decorating sheet 20 is obtained by transferring a concavo-convex pattern to the thermal transfer sheet 10 having a smooth surface by hot embossing. The article surface decorating sheet 20 forms an article surface decorating patch 30 by providing the adhesive layer 14 on the back surface thereof.

  FIG. 2 is a schematic cross-sectional view of the thermal transfer sheet 10 used for manufacturing the article surface decorating sheet 20. The thermal transfer sheet 10 includes a nonwoven fabric substrate 11, a surface layer 12 having a thickness of 1 to 100 μm including a polymer elastic body, and a hot-melt adhesive disposed between the nonwoven fabric substrate 11 and the surface layer 12. And an intermediate layer 13 having a thickness of 10 to 150 μm. The nonwoven fabric substrate 11 includes an entangled body of fiber bundles of ultrafine fibers having a fineness of 0.8 dtex or less. Furthermore, the polymer elastic body is provided in the space between the fibers of the nonwoven fabric substrate 11 as necessary.

  FIG. 3 is a scanning electron microscope (SEM) image of an example of an embossed portion of the article surface decorating sheet of the present embodiment. In FIG. 3, 1a is a fiber bundle of ultrafine fibers having a fineness of 0.8 dtex or less forming a nonwoven fabric substrate, a part of the fiber bundle is contoured, and a dotted line is an auxiliary line.

  As shown in FIG. 3, the fiber bundle is formed so that a plurality of ultrafine fibers are converged. And as for the nonwoven fabric base material containing the entangled body of the fiber bundle of an ultrafine fiber, the average value of the distance between the fiber bundles of the embossed part in the thickness direction cross section is 0-10 micrometers, Preferably it is 0-8 micrometers. The distance between such narrow fiber bundles is formed by densifying the fiber bundles that form the nonwoven fabric substrate by hot embossing.

  A method for measuring and calculating an average value of the distance between fiber bundles in the cross section in the thickness direction will be described with reference to FIG. An arbitrary cross section parallel to the thickness direction of the nonwoven fabric substrate as shown in FIG. 3 is photographed with a scanning electron microscope (SEM) at a magnification of 150 times. Then, 10 auxiliary lines are drawn at substantially equal intervals in parallel with the thickness direction of the sheet on the photographed image. Then, the total distance (A) between all the fiber bundles that have passed the 10 auxiliary lines (between the outer circumferences of the fiber bundles) is obtained. And the total of the number of fiber bundles which passed 10 auxiliary lines is calculated | required, and the number which subtracted 10 from the total of the number of fiber bundles is made into the number (B) between fiber bundles. Then, a value obtained by dividing the total distance (A) by the number (B) between the fiber bundles, that is, (A) / (B) is calculated as an average value of the distances between the fiber bundles in the thickness direction. Note that the fiber bundle counting method in the cross-sectional direction counts not only a circular fiber bundle but also an elliptical fiber bundle extending obliquely. However, the fiber bundles that substantially form bundles are counted. And it is preferable that all the average values of the distance between fiber bundles on each line of arbitrary 10 points are 0 to 10 μm, and more preferably 0 to 8 μm.

  The number of ultrafine fibers forming the fiber bundle is preferably 5 to 1000, more preferably 5 to 200, particularly 10 to 50, and more preferably 10 to 30. Moreover, as an average diameter of a fiber bundle, it is preferable that it is 1-50 micrometers, Furthermore, it is 10-30 micrometers. When the number of ultrafine fibers forming the fiber bundle is too large or the average diameter of the fiber bundle is too large, the fiber bundle forming the nonwoven fabric base material by heat embossing is difficult to be densified, and the distance between the fiber bundles There is a tendency that it is difficult to adjust the average value of 0 to 0 to 10 μm. Further, when the number of ultrafine fibers forming the fiber bundle is too small or the average diameter of the fiber bundle is too small, the fiber bundle forming the nonwoven fabric substrate by the hot embossing tends to be difficult to be densified. In addition, the average diameter of the fiber bundles is an image obtained by photographing the cross section in the thickness direction of the article surface decorative sheet with an SEM, and specifies the average of 100 fiber bundles on average, and the area surrounded by the outer shape. It shall mean the diameter of a circle having an equivalent area.

  The fineness of the ultrafine fiber is 0.8 dtex or less, preferably 0.5 dtex or less, more preferably 0.1 dtex or less, and particularly preferably 0.08 dtex or less. In addition, although a minimum is not specifically limited, It is preferable that it is about 0.01 dtex. When the fineness of the ultrafine fiber exceeds 0.8 dtex, the bulkiness of the fiber increases, and the fiber bundle forming the nonwoven fabric base material by hot embossing is difficult to be densified. As a result, it is difficult to accurately transfer the uneven pattern having a large height difference.

  The fiber bundle forming the nonwoven fabric substrate is formed of long ultrafine fibers, and the fiber bundle forming the nonwoven fabric substrate is densified by hot embossing, and the average distance between the fiber bundles is calculated. It is preferable from the viewpoint of easy adjustment to 0 to 10 μm. Here, the long fiber means that the short fiber is not cut into 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 that the fiber density of the fiber bundle can be sufficiently increased. If the ultrafine fiber is too short, it tends to be difficult to increase the density of the fiber bundle. Although an upper limit is not specifically limited, For example, in the case of the nonwoven fabric manufactured by the spunbond method, the fiber length of several m, several hundred m, several km or more spun continuously may be sufficient. Further, these fibers may be mixed with several kinds of fibers instead of single.

The resin that forms the ultrafine fibers is not particularly limited. Specific examples thereof include, for example, polyester resins such as polyethylene terephthalate (PET), polytrimethylene terephthalate, polybutylene terephthalate (PBT), and polyester elastomer; polyamide 6, polyamide 66, polyamide 610, aromatic polyamide, polyamide elastomer, and the like. Polyamide resins; acrylic resins; olefin resins; fibers formed from synthetic resins having fiber-forming ability such as polyvinyl alcohol resins. These may be used alone or in combination of two or more. Among these, polyester resins and polyamide resins are preferable from the viewpoint of excellent melt spinnability. In particular, a polyester having a glass transition temperature (T _g ) of 100 to 120 ° C., more preferably 105 to 115 ° C. is preferable.

Ultrafine fibers T _g comprises polyester 100 to 120 ° C., in order to have excellent stretchability during softening due to heating at the time of thermal transfer processing to the thermal transfer-receiving sheet obtained, transfer of large uneven pattern of height difference Are better. When _Tg is less than 100 ° C., solidification after thermal transfer tends to take time.

For example, T _g is obtained by 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). It is obtained by measuring the dynamic viscoelastic behavior under the conditions of ˜250 ° C., a temperature rising rate of 3 ° C./min, a strain of 5 μm / 20 mm, and a measurement frequency of 10 Hz.

Specific examples of the polyester a T _g is 100 to 120 ° C., for example, polyethylene terephthalate structural units disturb the structure of the linear to modified polyethylene terephthalate containing, as constituent units copolymerizable component, in particular, isophthalic acid, phthalic acid, Examples thereof include 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. More specifically, modified polyethylene terephthalate containing 2 to 12 mol% of isophthalic acid unit as a monomer component is preferable.

  The voids between the fibers or fiber bundles of the nonwoven fabric substrate may contain a polymer elastic body as necessary for the purpose of imparting shape stability or providing a sense of fulfillment. The kind of polymer elastic body is not particularly limited. Specific examples thereof include various polyurethanes such as polycarbonate polyurethane, polyester polyurethane, and polyether polyurethane, acrylic elastic bodies, polyurethane acrylic composite elastic bodies, polyvinyl chloride, and synthetic rubber. Among these, polyurethane is preferable from the viewpoint of excellent adhesiveness and mechanical properties. Moreover, you may mix | blend well-known various additives with a polymeric elastic body as needed. The polymer elastic body is preferably a crosslinked polymer elastic body, particularly a crosslinkable polyurethane having a mass reduction rate of 5% by mass or less with respect to immersion in N, N-dimethylformamide (DMF). Since the crosslinked polymer elastic body is less deformed due to elastic recovery after hot pressing, it becomes easy to increase the density so that the average value of the distance between the fiber bundles becomes 0 to 10 μm by hot embossing.

  Such a crosslinked polyurethane is preferably formed using an aqueous emulsion of a crosslinkable non-porous polyurethane. Specific examples of such an aqueous emulsion of a crosslinkable polyurethane include, for example, an aqueous emulsion of polycarbonate polyurethane, polyester polyurethane, polyether polyurethane, and polycarbonate / ether polyurethane that forms a crosslinked structure after drying. .

  As a content rate of the polymeric elastic body in a nonwoven fabric base material, it is 5-40 mass%, Furthermore, it is 10-35 mass%, It is especially 15-30 mass%. This is preferable because the average value of the distance can be easily increased to 0 to 10 μm.

The apparent density of the nonwoven fabric substrate is 0.50 g / cm ³ or more, and further 0.50 to
0.85 g / cm ^3, and particularly preferably from 0.50~0.80g / cm ^3. In the case of such a high apparent density, a high sense of fulfillment is obtained.

  Although the thickness of a nonwoven fabric base material is not specifically limited, 200-1000 micrometers, Furthermore, it is preferable that it is 300-700 micrometers, especially 350-500 micrometers from the point from which a thin article | item surface decoration sheet is obtained.

  The surface layer of the article surface decorating sheet or the surface layer of the thermal transfer sheet is a layer having a thickness of 1 to 100 μm mainly composed of a polymer elastic body.

  The type of the polymer elastic body for forming the surface layer is not particularly limited. Specific examples thereof include various polyurethanes such as polycarbonate polyurethane, polyester polyurethane and polyether polyurethane, acrylic elastic bodies, polyurethane acrylic composite elastic bodies, polyvinyl chloride elastic bodies, synthetic rubbers and the like. These polymer elastic bodies may be used alone or in combination of two or more. Among these, polyurethane is preferable from the viewpoint of excellent adhesiveness, mechanical properties such as wear resistance and bending resistance. The polymer elastic body may contain various known additives as required.

  The polymer elastic body forming the surface layer is preferably a one-pack type non-crosslinkable polymer elastic body. Since the cross-linked polymer elastic body is difficult to be plasticized in the subsequent thermal transfer process, the embossing property is lowered. The surface layer may have a laminated structure in which an anchor coat layer is provided for the purpose of improving adhesiveness, or a top coat layer is provided on the surface.

  The thickness of the surface layer is 1 to 100 μm, preferably 15 to 80 μm, and more preferably 20 to 50 μm. When the thickness of the surface layer is less than 1 μm, the heat resistance of the surface of the obtained article surface decorating sheet tends to be lowered or the wear resistance tends to be lowered. Moreover, when the thickness of a surface layer exceeds 100 micrometers, since an article surface decorating sheet becomes thick, it is unpreferable.

  The article surface decorative sheet and the heat-transferable sheet include an intermediate layer having a thickness of 10 to 150 μm mainly composed of a hot-melt adhesive that bonds the nonwoven fabric substrate and the surface layer. The hot-melt adhesive has thermoplasticity before curing. Such an intermediate layer having a thickness of 10 to 150 μm mainly composed of a hot-melt adhesive contributes to an improvement in thermal transferability when heat embossing a heat-transfer transfer sheet.

  The hot-melt adhesive is not particularly limited as long as it is a conventionally known hot-melt adhesive that melts by heating and then re-solidifies by being cooled. Specific examples include hot melt adhesives such as polyurethane, polyester, polyolefin, acrylic, vinyl acetate, polystyrene, and epoxy. The hot melt adhesive may be any of a crosslinked type, a semi-crosslinked type, and a non-crosslinked type, but the non-crosslinked type is preferable from the viewpoint of excellent thermal transferability. A hot melt urethane adhesive having a softening temperature of 150 ° C. or lower, more preferably 130 ° C. or lower, is particularly preferred from the viewpoint of excellent balance between thermal transfer properties, heat resistance, wear resistance, and the like of the heat transfer sheet. The softening temperature is measured, for example, by preparing a dry film of 50 μm, then increasing the temperature at a constant temperature while applying a constant load, and specifying the temperature at which it begins to grow sharply or the temperature at which it cuts sharply. be able to.

Further, the softening temperature of the hot melt adhesive is 0 to 30 ° C. than the T _g of the ultrafine fibers, further preferably higher 10 to 20 ° C.. In such a case, because the softening temperature T _g of the hot-melt adhesive of the ultrafine fibers is closer, by heat embossing, made clearly uneven pattern on the intermediate layer and the nonwoven fabric base material is likely to be transferred. When the softening temperature of the hot-melt adhesive is too high, the transferability to the intermediate layer is reduced, and when the temperature of hot embossing is excessively increased for clear transfer to the intermediate layer, the ultrafine fibers are The texture is lowered by fusing to form a film. In addition, when the softening temperature of the hot melt adhesive is too low, the transferability to the nonwoven fabric substrate is lowered, and when the temperature of the heat embossing is excessively increased to clearly transfer to the nonwoven fabric substrate, There is a possibility that the hot-melt adhesive may be melted or decomposed.

  The thickness of the intermediate layer is 10 to 150 μm, preferably 20 to 130 μm, and more preferably 30 to 120 μm. When the thickness of the intermediate layer exceeds 150 μm, the thickness of the article surface decorating sheet is increased.

  The thickness of each layer varies slightly depending on each region due to a difference in pressure applied in the pressing step for hot embossing, but in this embodiment, the region with the lowest compression rate, i.e., the non-embossed portion. The average thickness is used as a reference for thickness.

  The thickness of the article surface decorating sheet and the thermal transfer sheet of the present embodiment is 300 to 1000 μm, and more preferably 300 to 800 μm, even when decorating the surface of an article including a curved surface. It is preferable from the point.

  The article surface decorative sheet of the present embodiment is manufactured by forming a pattern including an embossed part and a non-embossed part on the surface layer side of the heat-transferable sheet by thermally transferring an uneven pattern using an embossing roll or the like. .

  Further, the total thickness of the surface layer and the intermediate layer is preferably 40 to 180 μm, more preferably 50 to 100 μm. If the total thickness of the surface layer and the intermediate layer is too thin, surface characteristics such as wear resistance will be insufficient, and if the total thickness of the surface layer and the intermediate layer is too thick, the surface of the article There exists a tendency for the whole decorating sheet to become thick too much, and the designability falls or it becomes difficult to stick together.

  The height difference between the embossed part and the non-embossed part is preferably 100 to 500 μm, more preferably 150 to 400 μm, and even more preferably 160 to 350 μm. If the height difference is too small, the contour formed by the embossing becomes unclear, and if the height difference is too large, it tends to be difficult to manufacture.

  Further, the height difference between the embossed portion and the non-embossed portion is larger than the total thickness of the surface layer and the intermediate layer. Specifically, the height difference between the embossed portion and the non-embossed portion is larger than the surface layer. When the thickness is 1.1 times or more, more than 2 times the total thickness of the intermediate layer, the uneven pattern is more clearly transferred to the nonwoven fabric substrate and the contour is accurately expressed. This is preferable.

  In the article surface decorating sheet 20 of the present embodiment, as shown in FIG. 1, when a concavo-convex pattern having a large height difference is formed by hot embossing, not only the surface layer 2 and the intermediate layer 3 but also the nonwoven fabric base material The concavo-convex pattern is transferred so as to reach 1. As a result, at least in the region R where the embossed portion H is formed, the nonwoven fabric substrate 1 is densified so that the average value of the distance between the ultrafine fiber bundles is 0 to 10 μm.

In addition, since the article surface decorating sheet 20 includes a nonwoven fabric base material that has been densified by hot embossing, it is excellent in a sense of fulfillment. Specifically, a region is provided in which the thickness when measured with a constant pressure thickness measuring instrument with a load of 240 gf / cm ² is maintained at 90% or more of the thickness measured with an unloaded SEM.

In addition, the thickness when applying a load of 240 gf / cm ² and measuring with a constant pressure thickness measuring device is JIS thickness measuring device with a load of 240 gf / cm ² according to JISL1096 (for example, Ozaki Mfg. Co., Ltd. JIS constant pressure thickness measurement). Machine). In addition, the thickness measured with a scanning microscope (SEM) in an unloaded state is taken at three points selected on average from a photograph taken by a scanning electron microscope (SEM) of a cross section of a portion measured with a constant pressure thickness measuring instrument. Calculated by averaging thickness.

  As shown in FIG. 1, the article surface decorating sheet 20 is used by adhering to the surface of the molded body 31, for example. By providing the adhesive layer 14 on the back surface of the article surface decorating sheet 20, an article surface decorating patch is obtained. The article surface decoration patch is used, for example, by laminating an adhesive layer on the back side of the nonwoven fabric substrate of the article surface decoration sheet, and bonding and adhering to the surface of the molded body with an adhesive layer. It is done. A decorative molded body having a three-dimensional leather-like design on the surface layer can be easily manufactured by bonding the surface of the molded body to the surface of the molded article.

  Next, an example of the manufacturing method of an article surface decorating sheet is demonstrated.

(1) Step of preparing a nonwoven fabric base material including an intertwined fiber bundle of ultrafine fibers having a fineness of 0.8 dtex or less In this step, first, a long fiber web made of sea-island type composite fibers is produced by melt spinning. For example, there is a method in which a sea-island type composite fiber is melt composite-spun, and the sea-island type composite fiber is collected on a net without being cut using a so-called spunbond method to form a web. The sea component of the sea-island type composite fiber is extracted or decomposed and removed at an appropriate later stage. By this decomposition removal or extraction removal, a fiber bundle of ultrafine fibers having a fineness of 0.8 dtex or less is formed.

  The spunbond method is preferably 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. By such a method, a long fiber web is formed. 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.

  As the resin that forms the island component of the sea-island type composite fiber, the fiber that forms the ultrafine fiber described above is 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.

The temperature of the hot press treatment for fusing the formed web is preferably 10 ° C. or more lower than the melting point of the component constituting the sea component of the sea-island composite fiber. If the temperature of the hot press treatment is 10 ° C or more lower than the melting point of the sea component, formation of entanglement defects or needle holes when entangled webs after stacking while maintaining good web form stability Can be made into a high-quality nonwoven fabric. The web basis weight after thermal pressing, is preferably in the range of 20 to 60 g / m ^2. By being in the range of 20 to 60 g / m ² , good form retention can be maintained in the subsequent web entanglement treatment.

  Next, a web entangled sheet is formed by stacking and entangling about 4 to 100 webs obtained. The web entangled sheet is formed by performing an entanglement treatment on the web using a known nonwoven fabric manufacturing method such as needle punching or high-pressure water flow treatment. Below, the entanglement process by a needle punch is demonstrated in detail as a typical example.

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

  Next, if necessary, the apparent density and the entanglement degree of the web entangled sheet are increased by thermally shrinking the web entangled sheet. In addition, the web entangled sheet containing a long fiber shrink | contracts greatly by heat shrink compared with the web entangled sheet containing a short fiber. The apparent density of the web entangled sheet that has been subjected to the heat shrinkage treatment may be further increased by heating rolls or hot pressing.

  The change in the basis weight of the web entangled sheet due to the heat shrinkage treatment is 1.1 times (mass ratio) or more, further 1.3 times or more and 2.0 times or less, compared with the basis weight before the shrinkage treatment. Is preferably 1.6 times or less.

  In addition, you may provide a polymeric elastic body to a web entanglement sheet before or after the ultrafine fiberization process mentioned later as needed.

  Examples of the method for imparting the polymer elastic body to the web entangled sheet include a method of impregnating the web entangled sheet with a solution or emulsion of the polymer elastic body and then coagulating the polymer elastic body. As a method of impregnating the web entangled sheet with the solution or emulsion of the polymer elastic body, a process of immersing the solution or emulsion in the web entangled sheet so as to be in a predetermined impregnated state and squeezing with a press roll or the like is performed once. Or the dip nip method performed several times is used preferably. 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.

  The polymer elastic body is fixed to the web entangled sheet by impregnating the web entangled sheet with a solution or emulsion of the polymer elastic body and solidifying the polymer elastic body. In order to crosslink the crosslinkable polymer elastic body, it is preferable to perform a curing treatment by heat treatment after solidification and drying.

  The polymer elastic solution or emulsion is not limited to the effects of the present invention. Colorants such as dyes and pigments, coagulation regulators, antioxidants, ultraviolet absorbers, fluorescent agents, antifungal agents, and penetrating agents. Contains anti-foaming agents, antifoaming agents, lubricants, water repellents, oil repellents, thickeners, extenders, curing accelerators, foaming agents, water-soluble polymer compounds such as polyvinyl alcohol and carboxymethyl cellulose, inorganic fine particles, conductive agents, etc. May be.

  The sea-island composite fibers in the web-entangled sheet are converted into ultrafine fiber bundles 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.

  Through the above-described steps, a nonwoven fabric substrate including an entangled body of fiber bundles of ultrafine fibers having a fineness of 0.8 dtex or less is prepared. The nonwoven fabric substrate thus obtained is usually adjusted to the desired thickness by slicing or grinding.

  (2) A step of forming a surface layer having a thickness of 1 to 100 μm containing a polymer elastic body on the surface of the release paper

  In this step, first, a sheet mainly composed of a polymer elastic body serving as a surface layer is formed on the surface of the release paper.

  The method of forming a sheet containing a polymer elastic body to be a surface layer on the surface of the release paper is not particularly limited, for example, after applying a solution or emulsion of the polymer elastic body on the release paper, to dry and solidify, Examples thereof include a so-called dry surface forming method, and a method of forming a polymer elastic film melted on a release paper using a T-die and cooling to solidify.

  (3) A hot melt adhesive solution coating film is formed on the surface layer formed on the surface of the release paper so that the dry thickness is 10 to 150 μm, and the nonwoven fabric substrate is pressure-bonded to the coating film. And forming a heat-transfer sheet by removing the release paper by adhering the nonwoven fabric substrate and the hot melt adhesive while removing the solvent in the coating film.

  A resin component mainly composed of a hot melt adhesive for forming an intermediate layer having a thickness of 10 to 150 μm is applied to the surface of a sheet containing a polymer elastic body, which is a surface layer formed on a release paper. .

  The properties of the hot melt adhesive are usually solid at room temperature. Therefore, the formed intermediate layer is also solid. Such a hot-melt adhesive is usually applied by adjusting the viscosity so that a solventless solid hot-melt adhesive can be applied. When a molten hot melt adhesive is applied to a polymer elastic sheet for forming the surface layer, the polymer elastic sheet receives a thermal history. In order to avoid such a thermal history, it is preferable to form a coating film using a solution type hot melt adhesive in which a solid hot melt adhesive is dissolved in a solvent.

  A coating film is formed on the surface of the sheet for forming the surface layer formed on the release paper using a solution-type hot melt adhesive, and before the solvent in the solution is completely dried, By bonding the prepared nonwoven fabric base material and removing the solvent by drying, the nonwoven fabric base material and the surface layer are integrated. At this time, if necessary, the hot-melt adhesive may be hot-pressed at a temperature at which the hot-melt adhesive is not cured. And after a hot-melt-type adhesive agent and a nonwoven fabric base material are adhere | attached, a thermal transfer sheet is formed by peeling a release paper from a surface layer.

  (4) A step of embossing the heat-transferred sheet by hot embossing

  A decorative sheet having a concavo-convex pattern such as a textured pattern is obtained by embossing the heat-transferable sheet by hot embossing from the side where the surface layer is laminated.

  As the heat embossing, the surface layer of the thermal transfer sheet is pressed against the embossing roll between the embossing roll having the embossed pattern formed on the heated surface with unevenness and the surface smooth backup roll. Let it pass.

  The level difference of the unevenness formed on the surface of the embossing roll is appropriately selected according to the thickness of the surface layer and the intermediate layer of the heat-transferable sheet, and specifically, for example, 100 to 500 μm, and further 150 to It is preferable that it is 400 micrometers from the point from which a clear embossed pattern is formed.

Also, the temperature and pressure of the embossing roll are not particularly limited as long as the embossing roll is sufficiently embossed on the heat transfer sheet. For example, a temperature below the melting point and the like in the above T _g of the ultrafine fibers. In this way, an article surface decorating sheet is obtained.

  An article surface decorative sheet having a leather-like appearance having a concavo-convex pattern such as a textured pattern is obtained by thermally transferring the concavo-convex pattern to the heat-transferable sheet from the side where the surface layer is laminated by heat embossing or the like.

  The conditions for hot embossing are not particularly limited, but conditions are selected so that the nonwoven fabric substrate can be compressed so that the average value of the distance between the fiber bundles in the cross section in the thickness direction is 0 to 10 μm at least in the embossed portion. Specifically, for example, the surface temperature is 100 to 180 ° C., the press pressure is 0.1 to 1.0 MPa, the press time is 1 to 3 m / min, and the temperature is 130 to 150 ° C., the press pressure is 0.1. Roll pressing is performed under the conditions of 2 to 0.5 MPa, pressing time of 1 to 3 m / min, in particular, temperature of 130 to 150 ° C., pressing pressure of 0.4 to 0.8 MPa, pressing time of 1 to 3 m / min. Such a method is preferably used. In the case of a roll press, the processing speed is preferably about 0.5 to 5 m / min, more preferably about 1 to 3 m / min, for example. Further, the surface temperature is preferably 10 to 30 ° C., more preferably 15 to 25 ° C. higher than the softening temperature of the hot melt adhesive, from the viewpoint of excellent transferability. In addition, when press temperature and press pressure are too high, it is unpreferable from the point that a fiber may fuse | melt and form a film. By such treatment, at least at the embossed part, the average value of the distance between the fiber bundles in the cross section in the thickness direction of the nonwoven fabric substrate is adjusted to be 0 to 10 μm.

  The article surface decorative sheet thus obtained has an adhesive layer formed on the back surface thereof and is bonded to the surface of a molded article or various articles. The adhesive layer can be formed, for example, by attaching a double-sided tape to the back side of the article surface decorating sheet. By adhering such an article surface decorative sheet to the molded body, a decorated molded body having a leather-like appearance with a three-dimensional feeling such as a textured surface is obtained. The article surface decorating sheet of the present embodiment is used for thinness, specifically, for example, the surface of a single-lens reflex camera housing or camera grip, the housing or cover of a mobile terminal body, a vehicle interior material It is preferably used for decorating cosmetic cases and the like.

  Hereinafter, the present invention will be described more specifically with reference to examples. The scope of the present invention is not limited by the examples.

[Example 1]
Ethylene-modified polyvinyl alcohol as the thermoplastic resin of the sea component (content 8.5 mole% of ethylene units, polymerization degree 380, saponification degree 98.7 mol%), with T _g is 110 ° C. As the thermoplastic resin of the island component A certain isophthalic acid-modified polyethylene terephthalate (content of isophthalic acid unit: 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 type long fiber was spun. The spun sea-island long fibers were continuously deposited on the movable net while sucking 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 long fibers deposited on the net were lightly pressed with a 42 ° C. metal roll. Then, the sea-island long fibers were peeled from the net, and hot-pressed at a linear pressure of 200 N / mm by passing between a metal roll with a lattice pattern with a surface temperature of 75 ° C. and a back roll. In this way, a long fiber web having a basis weight 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 68%, 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 crosslinkable non-porous polyurethane having a mass reduction rate of 0.5% by mass with respect to DMF immersion as follows. A cross-linked water-based polyurethane emulsion (solid content concentration 30%) mainly composed of polycarbonate / ether-based polyurethane was impregnated with a densified entangled web. And the water | moisture content was dried with the drying furnace of 150 degreeC, and also the polyurethane was bridge | crosslinked. A polyurethane entangled web composite having a polyurethane / entangled web mass ratio of 18/82 was thus 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 long fibers, and dried in a drying furnace at 120 ° C. to obtain a thickness. A nonwoven substrate of about 1000 μm was obtained.

The mass ratio of polyurethane / fiber entangled body of the obtained nonwoven fabric base material was 22/78, and its apparent density was 0.53 g / cm ³ . Moreover, the fineness of the ultrafine fiber of the fiber entangled body was 0.08 dtex.

  And the obtained nonwoven fabric base material was divided | segmented into 2 to the thickness direction, and was ground to 370 micrometers.

  On the other hand, a DMF solution of non-crosslinkable silicon-modified polycarbonate polyurethane was applied as a surface layer on the release paper, and dried to form a surface layer sheet having a thickness of 30 μm.

  Then, a polycarbonate hot melt adhesive solution having a solid content of about 50% was applied to the surface layer sheet so that the thickness after drying was 50 μm. The polycarbonate hot-melt adhesive was a non-crosslinked type and had a softening temperature of 120 ° C.

  And the nonwoven fabric base material was bonded together to the coating film of the DMF solution of the polycarbonate-type hot-melt adhesive formed on the surface layer sheet, and the solvent in the coating film was dried while lightly pressing. In this way, a heat transfer sheet was obtained. The thickness of the obtained thermal transfer sheet was 411 μm.

  And using the embossing roll which has a trapezoid-shaped convex part on the surface with a height difference of 200 μm on the surface of the obtained thermal transfer sheet, the mold is formed at a roll temperature of 140 ° C., a press pressure of 0.4 MPa, and a processing speed of 2 m / min. By performing the pressing, an article surface decorative sheet provided with a leather-like design having a textured embossed portion with a height difference of 176 μm was obtained.

  A 200-times SEM image of the cross-section of the embossed part of the obtained article surface decorative sheet was taken. And the average value of the distance between the fiber bundles in a thickness direction cross section was calculated | required by the method as shown in FIG. 3 and the following.

  As shown in FIG. 3, ten auxiliary lines parallel to the thickness direction were drawn at an interval of about 80 μm in the range of 861 μm in the width direction of the article surface decorative sheet. And the sum total of the distance between fiber bundles (distance between the outer periphery of a fiber bundle) between the outlines of the several fiber bundle which each line passes was calculated | required for every line. And the distance sum (A) of the distance between fiber bundles in 10 lines was determined. On the other hand, the total number of ultrafine fiber bundles on 10 lines was determined, and the number of fiber bundles (B) obtained by subtracting 10 from the total number was determined. Then, the average value of the distances between the ultrafine fiber bundles was calculated by dividing the total distance (A) by the number of interfiber bundles (B). As a result, the average value of the distance between the ultrafine fiber bundles of the obtained article surface decorating sheet was 2.75 μm.

Moreover, when the thickness of the embossed part of the article surface decorative sheet was measured with a JIS thickness measuring instrument (Ozaki Mfg. Co., Ltd. constant pressure thickness measuring instrument) with a load of 240 gf / cm ² according to JIS L1096, the thickness was 227 μm. . On the other hand, the thickness of the same part measured by SEM was 235 μm. As a result, the ratio of the thickness when measured with a constant pressure thickness measuring instrument to the thickness measured with the SEM was 96.5%.

  The transferability of the concavo-convex pattern of the obtained article surface decorating sheet was evaluated as follows. The results are shown in Table 1.

<Evaluation of transferability>
Compared with a sample of a PVC sheet to which the embossed portion of the wrinkle pattern was transferred, the transferability of the wrinkle pattern was visually determined in three stages according to the following criteria.
Grade 1: The grain depth was deep, and the grain shape was clearly transferred from the top to the bottom.
2nd grade: Although the grain depth is deep, the contour is formed only in the range from the height near 2/3 of the grain top to the bottom side, and the contour is not clear in other parts.
Grade 3 ... The grain depth is shallow, and the contour is formed only in the range from the height near the half of the grain vertex to the bottom side, and the contour is not clear in other parts.

[Example 2]
In Example 1, instead of using isophthalic acid-modified polyethylene terephthalate having a T _g of 110 ° C. as the island component thermoplastic resin, the isophthalic acid modified polyethylene having a T _g of 120 ° C. as the island component thermoplastic resin. A thermal transfer sheet was obtained in the same manner as in Example 1 except that terephthalate was used, and an article surface decorative sheet was obtained. And it evaluated similarly. The results are shown in Table 1.

[Example 3]
In Example 1, instead of using isophthalic acid-modified polyethylene terephthalate whose T _g is 110 ° C. as the island component thermoplastic resin, isophthalic acid modified polyethylene whose T _g is 100 ° C. as the island component thermoplastic resin. A thermal transfer sheet was obtained in the same manner as in Example 1 except that terephthalate was used, and an article surface decorative sheet was obtained. And it evaluated similarly. The results are shown in Table 1.

[Example 4]
In Example 1, instead of using a polyurethane / fiber entangled mass ratio of 22/78, a non-woven fabric substrate having an apparent density of 0.69 g / cm ³ in which the polyurethane / fiber entangled mass ratio was 29/71 was used. Obtained the heat-transfer sheet | seat similarly to Example 1, and obtained the article | item surface decoration sheet. The results are shown in Table 1.

[Example 5]
In Example 1, instead of applying a polyurethane hot-melt adhesive to the surface layer sheet so that the thickness after drying becomes 50 μm, the polycarbonate hot-melt type so that the thickness after drying becomes 10 μm. A heat transfer sheet was obtained in the same manner as in Example 1 except that the adhesive was applied, and an article surface decorative sheet was obtained. And it evaluated similarly. The results are shown in Table 1.

[Example 6]
In Example 1, instead of applying a polycarbonate hot melt adhesive to the surface layer sheet so that the thickness after drying becomes 50 μm, the polycarbonate hot melt type so that the thickness after drying becomes 150 μm. A heat transfer sheet was obtained in the same manner as in Example 1 except that the adhesive was applied, and an article surface decorative sheet was obtained. And it evaluated similarly. The results are shown in Table 1.

[Example 7]
In Example 1, instead of forming a surface layer sheet having a thickness of 30 μm after drying on the release paper, the surface layer sheet was formed to have a thickness of 15 μm after drying. Similarly, a thermal transfer sheet was obtained, and an article surface decorative sheet was obtained. And it evaluated similarly. The results are shown in Table 1.

[Example 8]
In Example 1, instead of forming a surface layer sheet having a thickness of 30 μm after drying on the release paper, the surface layer sheet was formed to have a thickness of 50 μm after drying. Similarly, a thermal transfer sheet was obtained, and an article surface decorative sheet was obtained. And it evaluated similarly. The results are shown in Table 1.

[Example 9]
In Example 1, instead of impregnating the nonwoven fabric base material with a non-porous polyurethane having a mass reduction rate of 0.5% by mass with respect to DMF immersion, a foamed polyurethane having a mass reduction rate with respect to DMF of 100% by mass was obtained. A nonwoven fabric base material having a mass ratio of foamed polyurethane / fiber entanglement of 18/82 was formed by impregnating with a DMF solution of polyurethane for forming (solid content 20%) and wet coagulating. Except for the above changes, a heat transfer sheet was obtained in the same manner as in Example 1, and an article surface decorating sheet was obtained. And it evaluated similarly. The results are shown in Table 1.

[Comparative Example 1]
In Example 1, instead of using isophthalic acid-modified polyethylene terephthalate having a T _g of 110 ° C. as the island component thermoplastic resin, polyethylene terephthalate having a T _g of 130 ° C. was used as the island component thermoplastic resin. Except for the above, a heat transfer sheet was obtained in the same manner as in Example 1, and an article surface decorative sheet was obtained. And it evaluated similarly. The results are shown in Table 1.

[Comparative Example 2]
In Example 1, instead of applying a polycarbonate hot melt adhesive having a softening temperature of 120 ° C. to the surface layer sheet, it is not a hot melt adhesive.
A thermal transfer sheet was obtained in the same manner as in Example 1 except that a one-component polycarbonate adhesive with a softening temperature of 150 ° C. was applied, and an article surface decorative sheet was obtained. And it evaluated similarly. The results are shown in Table 1.

[Comparative Example 3]
In Example 1, instead of applying a polyurethane hot-melt adhesive to the surface layer sheet so that the thickness after drying becomes 50 μm, the polyurethane hot-melt type so that the thickness after drying becomes 8 μm. A heat transfer sheet was obtained in the same manner as in Example 1 except that the adhesive was applied, and an article surface decorative sheet was obtained. And it evaluated similarly. The results are shown in Table 1.

From the results of Table 1, the article surfaces of Examples 1 to 9 according to the present invention including an intermediate layer having a thickness of 10 to 150 μm containing a hot-melt adhesive and having an average distance between fiber bundles of 0 to 10 μm A deep wrinkle pattern was formed on each of the decorative sheets. On the other hand, T _g is the article surface decorative sheet of Comparative Example 1 using the PET ultrafine fibers is 130 ° C., was only shallow emboss pattern formation. In addition, only a shallow wrinkle pattern was formed on the article surface decorative sheet of Comparative Example 2 containing a one-component polycarbonate adhesive having a softening temperature of 150 ° C. as an intermediate layer. Moreover, only the shallow wrinkle pattern was formed also in the article | item surface decoration sheet | seat of the comparative example 3 containing the intermediate layer of thickness 8 micrometers. In Examples 1 and 3 of the difference between the T _g of the softening temperature and the ultrafine fibers of hot melt adhesive is 10 to 20 ° C., the difference between the T _g of the softening temperature and the ultrafine fibers of hot melt adhesive is 0 ℃ The contour was clearer than Example 2 and the formability was excellent.

  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 1,11 Nonwoven fabric base material 1a Ultrafine fiber fiber bundle 2,12 Surface layer 3,13 Intermediate layer 10 Heat transfer sheet 20 Article surface decoration sheet 30 Article surface decoration patch 31 Molded body 40 Decorated molded body H Embossed part

Claims (13)

An article surface decorative sheet having an embossed portion,
A non-woven fabric substrate, a surface layer of 1 to 100 μm containing a polymer elastic body, and an intermediate layer of 10 to 150 μm in thickness containing a hot melt adhesive that bonds the non-woven fabric substrate and the surface layer,
The nonwoven fabric base material includes an entangled body of fiber bundles of ultrafine fibers having a fineness of 0.8 dtex or less, and an average value of the distance between the fiber bundles in the thickness direction cross section at least in the embossed portion is 0 to 10 μm. An article surface decorative sheet as a feature. The article surface decorating sheet according to claim 1, wherein the hot melt adhesive has a softening temperature higher by 0 to 30 ° C than a glass transition temperature (T _g ) of the ultrafine fiber. Article surface decorative sheet of claim 2, wherein the ultrafine fibers comprise modified polyester having a T _g of 100 to 120 ° C..   The article surface decoration sheet according to any one of claims 1 to 3, wherein a difference in height between the embossed portion and the non-embossed portion is larger than a total thickness of the surface layer and the intermediate layer.   The article surface decorating sheet according to claim 4, wherein the height difference is 1.1 times or more of a total thickness of the surface layer and the intermediate layer.   The article surface decorative sheet according to claim 4 or 5, wherein the height difference is 150 µm or more.   The article | item surface decorating sheet of any one of Claims 1-6 containing 5-40 mass% of polymer elastic bodies by which the said nonwoven fabric base material was bridge | crosslinked. The ratio of the thickness when measured with a constant pressure thickness measuring device set to 240 gf / cm ² with respect to the thickness measured with a scanning microscope (SEM) at least in the embossed portion is 90% or more. The article | item surface decorating sheet of any one of these.   An article surface decorating patch comprising the article surface decorating sheet according to any one of claims 1 to 8, and an adhesive layer or an adhesive layer laminated on the back surface side.   A decorative molded body formed by adhering the article surface decorative sheet according to any one of claims 1 to 9 to a surface of a molded body. (1) T _g and the nonwoven fabric substrate comprising entangled body of fiber bundle following ultrafine fiber fineness 0.8dtex containing modified polyester is 100 to 120 ° C., the surface layer having a thickness of 1~100μm comprising elastic polymer And an intermediate layer having a thickness of 10 to 150 μm including a hot-melt adhesive having a softening temperature higher by 0 to 30 ° C. than T _g and bonding the nonwoven fabric substrate and the surface layer. The process of preparing
(2) A step of heat embossing the heat-transferable sheet so that an average value of the distance between the fiber bundles in the thickness direction cross section at least in the embossed portion is 0 to 10 μm. A method for producing a decorative sheet. The step (1)
(1a) preparing the nonwoven fabric substrate;
(1b) forming a surface layer having a thickness of 1 to 50 μm including the polymer elastic body on the surface of the release paper;
(1c) forming a coating film of the hot melt adhesive solution on the surface layer formed on the surface of the release paper so that the thickness upon drying is 10 to 150 μm;
(1d) The non-woven fabric substrate is pressure-bonded to the coating film, the non-woven fabric substrate and the hot-melt adhesive are bonded while removing the solvent in the coating film, and the release paper is removed. The manufacturing method of the article | item surface decorating sheet of Claim 11 provided with the process of forming a thermal transfer sheet.   The manufacturing method of the article | item surface decorating sheet of Claim 11 or 12 whose surface temperature of the embossing type | mold used for the said hot embossing is 10-30 degreeC higher than the softening temperature of the said hot-melt-type adhesive agent.