JP2023142996A - Decorative molding sheet, preform molded body shaped from the sheet, and decorative molded body - Google Patents

Abstract

To provide a decorative molding sheet that has a leather-like elastic touch, and accurately and easily maintains a grain unevenness formed on a surface without deforming the shape when manufacturing a preform molded body or a decorative molded body.SOLUTION: There is provided a decorative molding sheet comprising a fiber base material and a surface resin layer including at least one resin layer laminated and bonded to one side of the fiber base material. The surface resin layer is mainly made of polyurethane, has a textured surface, has a total thickness of 70 to 200 μm, and includes a high modulus layer having a 100% modulus of 9 to 30 MPa, and having a thickness of 20 to 150 μm.SELECTED DRAWING: Figure 1

Description

The present invention relates to a leather-like decorative molding sheet having a textured surface for decorating the surface of an article.

2. Description of the Related Art A leather-like decorative molding sheet having a textured surface for decorating the surface of an article is known. A three-dimensional shape is given to such a decorative molding sheet by thermoforming such as hot press molding, vacuum forming, pressure forming, vacuum pressure forming, etc. to make a preform molded body, and the preform is molded in a mold. A method of manufacturing a decorative molded body by in-mold decorative molding in which a body is housed and injection molded is known. Also known is a method of manufacturing a decorated molded body by bonding a preform molded body to a previously formed decorated molded body using an adhesive.

When manufacturing a preform molded body by vacuum-pressure forming or hot press molding a sheet for decorative molding, or when manufacturing a decorative molded body by housing the preform molded body in a mold, the surface may have a textured surface. The irregularities of the decorative molding sheet may become shallow or flattened, resulting in a decrease in three-dimensional tactile sensation.

In order to solve the above-mentioned problems, for example, Patent Document 1 below discloses a decorative molding sheet used for manufacturing a decorative molded object, which has a resin layer having a textured surface on the surface. Disclosed is a decorative molding sheet comprising a sheet main body and an elastic protective layer containing an elastic body that fills the recesses of the textured surface and has a tensile modulus of elasticity of 2 to 10 MPa at 20°C.

JP2020-179611A

According to the technique disclosed in Patent Document 1, when manufacturing a decorative molded body in which a decorative molding sheet is integrated on the surface of a resin molded body molded by injection molding, forming the decorative molding sheet on the decorative molding sheet The textured unevenness can be made difficult to collapse during injection molding. However, when manufacturing a sheet for decorative molding, the manufacturing process is complicated, such as forming and peeling off an elastic protective layer that will be peeled off later. In addition, the elastic protective layer makes it difficult for the entire decorative molding sheet to stretch, making it difficult for the decorative molding sheet to transfer the shape of the mold during preform molding and in-mold decorative molding, resulting in decreased thermoformability. There was a problem. Furthermore, since such an elastic protective layer is difficult to reuse, it is undesirable in view of the burden on the environment, and also has the drawback of increasing production costs.

The present invention provides a leather-like elastic feel that makes it easy to accurately maintain the textured unevenness formed on the surface without deforming it when manufacturing preform molded objects or decorative molded objects. An object of the present invention is to provide a decorative molding sheet with the following features.

One aspect of the present invention is a decorative molding sheet including a fiber base material and a surface resin layer including at least one resin layer laminated and bonded to one surface of the fiber base material, the surface resin layer being laminated and bonded to one surface of the fiber base material. , is mainly made of polyurethane, has a textured surface, has a total thickness of 70 to 200 μm, has a 100% modulus (hereinafter simply referred to as 100% modulus) at 20°C of 9 to 30 MPa, and , a decorative molding sheet containing a high modulus layer having a thickness of 20 to 150 μm. According to such a sheet for decorative molding, when manufacturing a preform molded object or a decorative molded object, it is easy to maintain the shape of the textured unevenness formed on the surface accurately without disturbing it. A decorative molding sheet with a leather-like elastic feel is obtained. Additionally, when performing in-mold decorative molding to integrate into an injection molded body, especially when injecting resin such as polycarbonate resin that is injection molded at a resin temperature exceeding 250°C, Therefore, it becomes easier to obtain a decorative molded article of good quality without causing defects such as wrinkles or tears in the surface resin layer and with less warping.

Further, it is preferable that the average value of the 100% modulus of the surface resin layer is 9 to 30 MPa from the viewpoint of achieving an excellent balance between maintaining the shape of the grain unevenness and providing a leather-like elastic feel.

Further, the surface resin layer includes a skin layer disposed on the surface and at least one intermediate layer not disposed on the surface, and the high modulus layer is at least one of the skin layer or the intermediate layer. It is preferable because it makes it easy to adjust the balance between maintaining the uneven shape and having a leather-like elastic feel.

In addition, it is preferable that the thickness ratio of the high modulus layer in the surface resin layer is 20 to 80% from the viewpoint of easily adjusting the balance between maintaining the shape of the grain unevenness and providing a leather-like elastic feel. .

Further, it is preferable that the maximum height Rz of the shape of the textured unevenness is 60 to 120 μm, since the effects of the present invention are particularly noticeable.

Another aspect of the present invention is a preform molded body used for manufacturing a decorative molded body, which is obtained by shaping the above-mentioned decorative molding sheet into a three-dimensional shape. Even after preform molding, such a preform molded object can maintain the textured surface formed on the surface without losing the leather-like elastic feel of the surface resin layer of the decorative molding sheet. Easy to maintain without changing.

Another aspect of the present invention is a decorated molded article comprising a decorated molded article and a decoration layer that decorates the surface of the decorated molded article, the decoration layer being as described above. It is a decorative molded body containing any of the decorative molding sheets. Such a decorative molded article can easily maintain the textured unevenness formed on the surface without losing the leather-like elastic feel of the surface resin layer of the decorative molded sheet.

According to the present invention, when performing molding to manufacture a preform molded object or a decorated molded object, the leather-like texture is easily maintained without deforming the textured unevenness formed on the surface. A decorative molding sheet with an elastic feel is obtained.

FIG. 1 is a schematic cross-sectional view of a decorative molding sheet 10 according to an embodiment. FIG. 2 is a schematic cross-sectional view of the decorative molding sheet 20 of the embodiment. FIG. 3 is a schematic cross-sectional view illustrating each step of preform molding the decorative molding sheet 10 of the embodiment. FIG. 4 is a schematic cross-sectional view illustrating each step of molding a decorative molded body using the preform molded body 30 of the decorative molding sheet 10.

Hereinafter, the decorative molding sheet of this embodiment will be described in detail with reference to the drawings.

FIG. 1 is a schematic cross-sectional view of a decorative molding sheet 10 of this embodiment. As shown in FIG. 1, the decorative molding sheet 10 is a decorative molding sheet that includes a fiber base material 1 and a surface resin layer 5 laminated and bonded to the fiber base material 1.

The surface resin layer 5 includes a first skin layer 4 mainly made of polyurethane, a second intermediate layer 3 mainly made of polyurethane, and a second adhesive layer mainly made of polyurethane for adhesion. This is a laminate including an intermediate layer 2. The skin layer 4 is a layer disposed on the surface (outer surface) side of the surface resin layer 5, and the first intermediate layer 3 is a layer disposed on the fiber base material 1 side that is not on the surface side of the skin layer 4. The second intermediate layer 2 is an adhesive layer formed when bonding the fiber base material 1 and the surface resin layer 5. A textured surface E is formed on the surface of the surface resin layer 5.

The surface resin layer 5 is a laminate having a total thickness of 70 to 200 μm. When the total thickness of the surface resin layer 5 is less than 70 μm, it becomes difficult to form a textured surface with height differences. Moreover, when it exceeds 200 μm, it becomes difficult to impart a three-dimensional shape by preform molding, etc., and there is a tendency that in-mold decorative moldability tends to deteriorate.

Such a surface resin layer 5 is adhered to the fiber base material 1 by a second intermediate layer 2 which is an adhesive layer containing a third polyurethane for adhesive use.

In the decorative molding sheet 10, at least one of the skin layer 4, the first intermediate layer 3, and the second intermediate layer 2 has a 100% modulus of 9 to 30 MPa at 20°C, and a thickness of It is a layer mainly made of polyurethane and has a thickness of 20 to 150 μm.

Further, it is preferable that the surface resin layer has an average value of 100% modulus at 20° C. of 5 to 30 MPa, more preferably 9 to 25 MPa, from the viewpoint of maintaining the grain unevenness more accurately. Here, the average value of 100% modulus of the surface resin layer is the sum of the 100% modulus of each layer forming the surface resin layer multiplied by the thickness ratio, and the average value of 100% modulus of all layers. is defined as For example, in the case of the decorative molding sheet 10, it is preferable that the average value of the 100% modulus of the skin layer 4, first intermediate layer 3, and second intermediate layer 2 is 5 to 30 MPa to prevent grain unevenness. This is preferable from the viewpoint of more accurate maintenance.

Moreover, FIG. 2 is a schematic cross-sectional view of a decorative molding sheet 20 of another example of the present embodiment. As shown in FIG. 2, the decorative molding sheet 20 is a decorative molding sheet that includes a fiber base material 1 and a surface resin layer 15 laminated and bonded to the fiber base material 1.

The surface resin layer 15 is a laminate of a first skin layer 14 mainly made of polyurethane and an intermediate layer 12 which is an adhesive layer containing polyurethane for adhesion. The skin layer 14 is a layer that is adhered to the fiber base material 1 via the intermediate layer 12, which is an adhesive layer, and is disposed on the surface side. A textured surface E is formed on the surface of the surface resin layer 15.

In the decorative molding sheet 20, the surface resin layer 15 has a total thickness of 70 to 200 μm, and the skin layer 14 or intermediate layer 12 has a 100% modulus of 9 to 30 MPa and a thickness of 20 to 150 μm. It is a high modulus layer.

In addition, in the surface resin layer 15 including the skin layer 14 and the intermediate layer 12, the average value of the 100% modulus is 5 to 30 MPa, and more preferably 9 to 25 MPa to maintain the shape of the grain unevenness. It is preferable because it has an excellent balance between elasticity and leather-like elastic feel.

In addition, in the above-mentioned sheet for decorative molding, when performing in-mold decorative molding, the thickness ratio of the high modulus layer in the surface resin layer is 20 to 80%, and more preferably 20 to 55%. is preferable because it is less likely to cause defects such as wrinkles and tears in the surface resin layer, it is easier to maintain the grain unevenness accurately, and it is easier to obtain a decorative molded product of good quality with less warpage.

Hereinafter, the decorative molding sheet as described above will be described in more detail with reference to its manufacturing method.

The fiber base material forming the decorative molding sheet includes a nonwoven fabric, a woven fabric, a knitted fabric, or a fiber entangled body that is a combination thereof. Preferably, the fiber entangled body includes an elastomer impregnated with a polymeric elastic body.

The type of fibers forming the fiber entanglement is not particularly limited. Specific examples of resins forming fibers include polyethylene terephthalate (PET), modified polyethylene terephthalate, polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polytriethylene terephthalate, polyhexamethylene terephthalate, and polypropylene terephthalate. , aromatic polyester resins such as polyethylene naphthalate; aliphatic polyester resins such as polylactic acid, polyethylene succinate, polybutylene succinate, polybutylene succinate adipate, polyhydroxybutyrate-polyhydroxyvalerate copolymer; Nylon resins such as nylon 6, nylon 66, nylon 610, nylon 10, nylon 11, nylon 12, nylon 6-12; polypropylene, polyethylene, polybutene, polymethylpentene, chlorine polyolefin, ethylene vinyl acetate copolymer, styrene Examples include polyolefin resins such as ethylene copolymers.

The resin used for manufacturing the fiber base material may contain various additives, such as colorants, color inhibitors, heat resistant agents, flame retardants, lubricants, etc., to the extent that the objects and effects of the present invention are not impaired. Antifouling agents, optical brighteners, matting agents, gloss improvers, antistatic agents, fragrances, deodorants, catalysts, antibacterial agents, anti-mite agents, inorganic fine particles, etc. may be added as necessary. .

Further, the fineness of the fibers forming the fiber entangled body is not particularly limited, but it is possible to include ultrafine fibers having a fineness of 1 dtex or less, more preferably 0.001 to 0.8 dtex, particularly 0.001 to 0.1 dtex. This is preferable because it makes it easy to obtain a fiber base material that has a supple texture that also provides a sense of fullness. The ultrafine fibers may exist as a fiber bundle formed by a plurality of ultrafine fibers bundled together, such as those formed through ultrafine fiber-forming fibers such as sea-island composite fibers.

Moreover, it is preferable that the fiber base material contains an elastic polymer material impregnated into the fiber entangled body. Specific examples of the polymeric elastomer to be impregnated into the fiber entangled body include polyurethane, acrylonitrile elastomer, olefin elastomer, polyester elastomer, polyamide elastomer, acrylic elastomer, and the like. Among these, polyurethane, and furthermore, water-based polyurethane obtained by coagulating a water-based polyurethane emulsion, and solvent-based polyurethane obtained by wet coagulating polyurethane dissolved in an organic solvent such as DMF, have excellent balance of physical properties. In particular, water-based polyurethane is preferable because of its low environmental impact. The content of the elastic polymer in the fiber base material is not particularly limited, but is preferably 1 to 50% by mass, more preferably 5 to 30% by mass.

Among these, a fiber base material containing a nonwoven fabric of ultrafine fibers impregnated with polyurethane is preferable because it is easy to obtain a decorative molding sheet that has a supple texture, a feeling of fullness, and excellent shape stability.

Further, the thickness of the fiber base material is not particularly limited, but it is preferably 0.1 to 2 mm, more preferably 0.2 to 1.5 mm. Further, the apparent density of the fiber base material is not particularly limited, but it is preferably 0.20 to 1.00 g/cm ³ , particularly 0.30 to 1.00 g/cm ³ .

One side of such a fiber base material contains a high modulus layer with a thickness of 20 to 150 μm mainly made of polyurethane with a 100% modulus of 9 to 30 MPa, and a total layer of 70 to 200 μm with a textured surface. A decorative molding sheet is obtained by adhering a thick surface resin layer.

Polyurethane is obtained by reacting urethane raw materials containing a polymer polyol, an organic diisocyanate compound, a chain extender, and a polyfunctional compound or acid group-containing compound used as necessary.

Specific examples of polymer polyols include polypropylene carbonate diol, poly(2-methyl-1,3-propylene carbonate) diol, polytetramethylene carbonate diol, polypentamethylene carbonate diol, polyhexamethylene carbonate diol, poly( 3-Methyl-1,5-pentylene carbonate) diol, polypentamethylene carbonate diol, polytetramethylene carbonate diol, polyoctamethylene carbonate diol, poly(2-methyl-1,8-octylene carbonate) diol, polynona Polycarbonate diols such as methylene carbonate diol, polydecamethylene polycarbonate diol, polydodecamethylene polycarbonate diol, etc., or copolymers thereof; polyethers such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, poly(methyltetramethylene glycol), etc. polybutylene adipate diol, polybutylene sebacate diol, polyhexamethylene adipate diol, poly(3-methyl-1,5-pentylene adipate) diol, poly(3-methyl-1, Examples include polyester diols such as 5-pentylene sebacate) diol and polycaprolactone diol, or copolymers thereof; and polymer diols such as polyester carbonate diol. These may be used alone or in combination of two or more.

Specific examples of organic diisocyanate compounds include aliphatic diisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, 1 , 4-bis(isocyanatomethyl)cyclohexane, and other alicyclic diisocyanates; 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), and xylylene diisocyanate, etc. Group diisocyanates; polyfunctional isocyanates, which are polyfunctional compounds that provide branched structures such as isocyanurate-type, biuret-type, and adduct-type trifunctional and tetrafunctional isocyanates, and isocyanate block forms thereof. These may be used alone or in combination of two or more.

Further, specific examples of chain extenders include hydrazine, ethylenediamine, propylene diamine, hexamethylene diamine, nonamethylene diamine, xylylene diamine, isophorone diamine, piperazine and derivatives thereof; adipic acid dihydrazide, isophthalic acid dihydrazide, etc. Diamines; triamines such as diethylenetriamine; tetramines such as triethylenetetramine; ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,4-bis(β-hydroxyethoxy)benzene, 1,4 -Diols such as cyclohexanediol; amino alcohols such as aminoethyl alcohol and aminopropyl alcohol; and the like. These may be used alone or in combination of two or more.

The type of polyurethane for forming the surface resin layer is not particularly limited, and specifically, for example, polyether polyurethane, polyester polyurethane, polycarbonate polyurethane, polyether-polyester polyurethane, silicone-modified polycarbonate. Examples include polyurethanes such as polyurethane-based polyurethanes.

In addition, the surface resin layer or each layer forming the surface resin layer is mainly made of polyurethane, and as necessary, colorants such as pigments and dyes, softeners, antifouling agents, hydrophilic agents, lubricants, deterioration prevention agents, etc. It may also contain additives such as UV absorbers, UV absorbers, and flame retardants. Note that "based on polyurethane" means that the surface resin layer or each layer forming the surface resin layer contains polyurethane in an amount of 50% by mass or more, preferably 80% by mass or more, and more preferably 90% by mass or more. .

The 100% modulus of polyurethane is determined by increasing the proportion of hard segments derived from the chain extender in the polyurethane raw material containing a polymer polyol, an organic diisocyanate compound, and a chain extender for polymerizing polyurethane. It becomes higher by increasing the strong pseudo-crystalline structure due to aggregation, increasing the cohesive force due to hydrogen bonding, or using a large amount of aromatic diisocyanate compound as the organic diisocyanate compound.

The surface resin layer includes a high modulus layer having a 100% modulus of 9 to 30 MPa and a thickness of 20 to 150 μm.

The 100% modulus of the high modulus layer is 9 to 30 MPa at 20° C., particularly preferably 20 to 30 MPa. When a high modulus layer is not included, the textured irregularities formed on the surface are likely to be deformed in the process of manufacturing a preform molded object or a decorated molded object. Further, when the 100% modulus of the high modulus layer exceeds 30 MPa, the sheet for decorative molding will have a hard surface feel like a resin.

Further, the thickness of the high modulus layer is 20 to 150 μm, preferably 20 to 100 μm, particularly preferably 20 to 80 μm. If the thickness of the high modulus layer is less than 20 μm, the textured surface formed on the surface is likely to change during the process of manufacturing a preform molded object or a decorated molded object, and , there is a tendency for in-mold decorative moldability to deteriorate. Moreover, when the thickness of the high modulus layer exceeds 150 μm, the sheet for decorative molding has a hard surface feel, and the in-mold decorative moldability tends to decrease.

When the surface resin layer has a laminated structure consisting of a plurality of layers having different types of 100% modulus, at least one of the layers includes a high modulus layer. For example, as shown in FIG. 1, in the case of a surface resin layer 5 having a laminated structure including a skin layer 4, a first intermediate layer 3, and a second intermediate layer 2, the skin layer 4 and the first intermediate layer At least one of the intermediate layer 3 and the second intermediate layer 2 is a high modulus layer. Further, as shown in FIG. 2, in the case of the surface resin layer 15 having a laminated structure including the skin layer 14 and the intermediate layer 12, at least one of the skin layer 14 and the intermediate layer 12 is a high modulus layer. .

Further, in the case of the surface resin layer 5 having a laminated structure including the skin layer 4, the first intermediate layer 3, and the second intermediate layer 2 as shown in FIG. The average value of the 100% modulus of the second intermediate layer 2 is preferably 5 to 30 MPa. Further, in the case of the surface resin layer 15 having a laminated structure including the skin layer 14 and the intermediate layer 12 as shown in FIG. 2, the average value of the 100% modulus of the skin layer 14 and the intermediate layer 12 is 5 to 30 MPa. It is preferable. If the average value of the 100% modulus of the surface resin layer is too low, the unevenness of the grain will easily deform in the process of manufacturing a preform molded object or a decorative molded object, and the in-mold processing Decorative moldability tends to decrease. Furthermore, if the average value of the 100% modulus is too high, the sheet for decorative molding will have a hard surface feel.

In addition, the 100% modulus of the layers other than the high modulus layer of the surface resin layer having a laminated structure is 0.1 to 8 MPa, furthermore, 1 to 5 MPa, and the total thickness is 20 to 100 μm, furthermore, is preferably 20 to 90 μm. If the layers other than the high modulus layer are too thick, the textured surface formed on the surface tends to change easily during the process of manufacturing a preform molded object or a decorated molded object. There is.

The total thickness of the surface resin layer as described above is 70 to 200 μm. If the total thickness of the surface resin layer is too thin, it becomes difficult to form a textured surface with height differences. Moreover, if the total thickness of the surface resin layer is too thick, it becomes difficult to impart a three-dimensional shape by preform molding or the like, and there is a tendency that in-mold decorative moldability deteriorates.

The surface resin layer laminated on the decorative molding sheet has a textured surface. Although the shape of the textured unevenness is not particularly limited, it is preferable that the maximum height Rz is 60 to 120 μm, more preferably 70 to 100 μm, since a leather-like textured design is likely to be formed. Further, the arithmetic mean roughness Ra is preferably 10 to 50 μm, more preferably 20 to 40 μm.

An example of a method for forming a surface resin layer having a textured surface is a method of forming a surface resin layer using a release paper having a leather-like textured surface. Specifically, a resin liquid of a resin composition containing polyurethane for forming each layer as described above is applied to the surface of a release paper having a textured surface, and is solidified to form a textured surface. A resin film is formed. Specifically, for example, when forming the surface resin layer 5 having a laminated structure including the skin layer 4, the first intermediate layer 3, and the second intermediate layer 2 as shown in FIG. A resin solution of a resin composition containing polyurethane for forming the skin layer 4 is applied to a release paper having an uneven surface, and after solidification, a resin solution containing polyurethane for forming the first intermediate layer 3 is applied. A resin liquid of the composition is applied and solidified.

Then, polyurethane is applied to the surface of the first intermediate layer 3 formed on the release paper having an uneven surface to form the second intermediate layer 2 which will serve as an adhesive layer, and the polyurethane is applied to the surface of the fiber base material. At the same time, if necessary, after adhering by hot pressing, the release paper is peeled off. In this way, the decorative molding sheet of this embodiment can be manufactured.

The thickness of the intermediate layer serving as the adhesive layer is not particularly limited, but it is preferably 15 to 100 μm, more preferably 20 to 90 μm, and particularly 30 to 80 μm. If the adhesive layer is too thin, the adhesive force tends to be insufficient, and if it is too thick, it tends to be difficult to give a three-dimensional shape by preform molding or the like.

Further, a top coat layer having a thickness of about 0.1 to 10 μm may be further formed on the uneven surface of the surface resin layer, if necessary, as long as the effects of the present invention are not impaired. When such a top coat layer is included, the top coat layer also constitutes a surface resin layer.

The overall thickness of the decorative molding sheet obtained in this way is not particularly limited, but it is preferably 0.5 to 5 mm, more preferably 0.1 to 3 mm, for preform moldings and decorative moldings. It is preferable from the viewpoint of excellent moldability when manufacturing. Further, the apparent density of the decorative molding sheet is preferably 0.3 to 1.5 g/cm ³ , more preferably 0.6 to 1.2 g/cm ³ .

The decorative molding sheet described above can be used for conventionally known decorative molding sheets without particular limitation. Specifically, it is preferably used, for example, as interior materials for vehicles and aircraft, exterior materials for housings of mobile phones, mobile devices, home appliances, etc., exterior materials for building materials, furniture miscellaneous goods, sporting goods, etc.

The decorated molded article of the present embodiment is a decorated molded article that includes a decorated molded article and a decoration layer that decorates the surface of the decorated molded article, and the decorated molded article includes the above-mentioned decoration layer. Including sheets for decorative molding. Such decorative molded bodies are manufactured by producing a preform molded body that has been given a three-dimensional shape by thermoforming such as hot press molding, vacuum forming, pressure forming, vacuum pressure forming, etc., and then molding the preform molded body with metal. Manufactured by in-mold decorative molding in which the product is placed in a mold and then injection molded. Another method includes a method of manufacturing a decorated molded body by bonding a preform molded body to a previously formed molded body to be decorated using an adhesive. Furthermore, as another method, while giving a three-dimensional shape to a decorative molding sheet by thermoforming such as vacuum forming, pressure forming, vacuum pressure forming, etc. to a preformed molded object to be decorated, There is also a method of manufacturing a decorated molded object by adhering and pasting it to a decorated molded object via an adhesive.

Hereinafter, a method of in-mold decorative molding, which is a method of housing a preform molded body in a mold and injection molding it, will be described in detail as a representative example of a method for manufacturing a decorated molded body.

Examples of methods for manufacturing a preform molded body by shaping a decorative molding sheet into a three-dimensional shape include vacuum pressure forming, vacuum forming, pressure forming, hot press molding, and the like. Among these, vacuum-pressure forming is particularly preferred because of its excellent shapeability. Hereinafter, as a representative example, a method for manufacturing a preform molded body by vacuum-pressure forming a sheet for decorative molding will be described in detail.

FIG. 3 is an explanatory diagram illustrating each process for molding the decorative molding sheet 10 into a preform molded body by vacuum-pressure molding.

As shown in FIG. 3(a), the vacuum pressure forming machine 50 includes an upper chamber box 41, a lower chamber box 42, a heater 33, a table 44, exhaust pipes 45a, 45b, and intake pipes 46a, 46b. Be prepared. The upper chamber box 41 and the lower chamber box 42 face each other and form an airtight chamber that accommodates the heater 33 and the table 44 therein by closing them. The table 44 is moved up and down by the piston 37.

In the method for manufacturing a preform molded body of this embodiment, first, as shown in FIG. 3(a), the base 31 is placed on the table 44, and the mold 32 is placed on it. The base 31 is provided above the table 44 in order to place the mold 32 thereon.

Then, as shown in FIG. 3(b), the decorative molding sheet 10 is placed so as to cover the mold 32 and the lower chamber box 42. In FIG. 3(b), the decorative molding sheet 10 is placed on the mating surface F of the upper chamber box 41 and the lower chamber box 42.

Then, as shown in FIG. 3(c), by lowering the upper chamber box 41, the upper chamber box 41 and the lower chamber box 42 are closed. By closing the upper chamber box 41 and the lower chamber box 42, an airtight first space S1 is formed between the upper chamber box 41 and the decorative molding sheet 10, and the lower chamber box 42 and the decorative molding sheet 10 are closed. An airtight second space S2 is formed between the sheet 10 and the sheet 10. Then, using a pressure reducing pump (not shown), the air in the first space S1 is exhausted from the exhaust pipe 45a, and the air in the second space S2 is exhausted from the exhaust pipe 45b to reduce the pressure. At this time, the pressures in the first space S1 and the second space S2 are reduced until they reach the same pressure.

Then, as shown in FIG. 3(d), the decorative molding sheet 10 is heated with a heater 33 to soften it. Then, as shown in FIG. 3(e), the table 44 is raised by the piston 37, and air is supplied from the intake pipe 46a provided in the upper chamber box 41 to the first space S1 to increase the atmospheric pressure. If necessary, the air pressure in the first space S1 and the second space S2 is reduced by sucking air in the second space S2 from the exhaust pipe 45b provided in the lower chamber box 42 to further lower the air pressure. Due to the difference, the softened decorative molding sheet 10 comes into close contact with the surface of the mold 32.

Then, as shown in FIG. 3F, by raising the upper chamber box 41 and opening the lower chamber box 42, and by moving the table 44, the preform molded body 30a onto which the shape of the mold 32 has been transferred is formed. It is formed. Then, the preform molded body 30a is released from the mold 32 and taken out.

In such vacuum pressure forming, the decorative molding sheet 10 is pressed into the mold 32 in a heated state. At this time, a change in shape may occur, such as the recesses of the textured surface formed on the surface resin layer becoming shallower. According to the decorative molding sheet of this embodiment, even if the mold 32 stretches the decorative molding sheet 10 in a heated state, the shape of the textured surface is difficult to change.

The preform molded body 30a molded in this way is trimmed to match the shape of the surface to which the decorated molded body is attached. In this way, a preform molded body 30 is obtained. Then, the preform molded body 30 is adhered to the surface of the decorated molded body prepared in advance using an adhesive, or the preform molded body 30 is attached to the surface of the decorated molded body which is a resin molded body molded by injection molding. It is used for in-mold decorative molding that integrates the preform molded body 30 at the same time as injection molding. In this way, a decorated molded article is obtained in which the decorative molding sheet 10 is laminated and integrated as a decorative layer on the decorated molded article.

Next, with reference to FIG. 4, a method of molding a decorative molded body in which a decorative molding sheet is laminated and integrated as a decorative layer by in-mold decorative molding using the preform molded body 30 will be described. explain in detail. According to the preform molded body using the decorative molding sheet of this embodiment, it is easy to accurately maintain the grain unevenness on the surface resin layer.

In FIG. 4, 30 is a preform molded body, 22a is a movable side mold, 22b is a fixed side mold, 23 is an injection part main body of an injection molding machine, 23a is a nozzle, 23b is a cylinder, 23c is an in-line screw, and 24 is a resin flow 7 is a resin molded body, 7a is a molten resin, and 40 is a decorative molded body. The movable side mold 22a and the fixed side mold 22b form an injection mold 22 that forms a cavity c. In this embodiment, the movable mold 22a is a female injection mold, and the fixed mold 22b is a male injection mold.

First, as shown in FIG. 4(a), the preform molded body 30 is accommodated in the recessed portion of the movable mold 22a for forming a cavity. At this time, the preform molded body 30 is arranged so that the textured surface of the surface resin layer of the preform molded body 30 contacts the surface of the recessed portion of the movable mold 22a.

Next, as shown in FIG. 4(b), the movable mold 22a and the fixed mold 22b are clamped. Then, as shown in FIG. 4C, a cavity c formed by clamping the movable mold 22a and the fixed mold 22b is filled with molten resin 7a. Specifically, by advancing the injection part 23 of the injection molding machine, bringing the nozzle 23a into contact with the resin inlet 24 formed in the fixed side mold 22b, and injecting the molten resin 7a within the cylinder 23b with the in-line screw 23c. , the molten resin 7a is filled into the cavity c at a predetermined filling pressure.

Injection molding conditions are determined depending on the thermal characteristics and melt viscosity of the resin to be injected, the shape of the resin molded product, and the resin thickness (resin temperature, mold temperature, injection pressure, injection speed, post-injection holding pressure, cooling time) is set appropriately.

The type of resin for the injection molded article to be molded is not particularly limited. Specific examples include acrylic resins such as polycarbonate resins, ABS resins, and PMMA resins, polyolefins such as polystyrene resins and polypropylene, polyesters such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), and various nylons. , COP resin, etc. Among these, in-mold decorative molding that is integrated into an injection molded object, especially when injecting resin such as polycarbonate resin that is injection molded at a resin temperature exceeding 250°C, causes wrinkles on the surface resin layer. It becomes easier to obtain a decorative molded product of good quality with less warpage and the like without causing defects such as cracks and tears.

Furthermore, the thickness of the injection molded article to be molded is not particularly limited, and is appropriately selected depending on the purpose and moldability. For example, when used in the housing of home appliances, the preferred range is 0.3 to 2 mm, more preferably 0.5 to 1.5 mm.

In the cooling process of injection molding, the decorated molded body 7, which is a resin molded body, is molded in the cavity c formed when the movable side mold 22a and the fixed side mold 22b are clamped. After cooling the laminate in which the preform molded body 30 stacked on the molded body 7 is integrated, for a predetermined period of time, the movable side mold 22a and the fixed side mold 22b are molded together, as shown in FIG. 4(d). It is opened and a decorated molded body 40 in which the decorated molded body 7 and the preform molded body 30 are laminated and integrated is taken out.

In such in-mold decorative molding, the surface resin layer is compressed from the textured surface during injection molding with the surface of the mold in contact with the textured surface of the decorative molding sheet 10. According to the decorative molding sheet of the present embodiment, the surface resin layer is not easily deformed even when the mold comes into contact with the textured surface, so that the textured surface is less likely to be deformed.

Hereinafter, the present invention will be explained in more detail with reference to Examples. Note that the present invention is not limited in any way by the examples.

First, the fiber base materials used in this example will be summarized below.

・PET nonwoven fabric: Obtained by removing the sea component from a long fiber sea-island type composite fiber nonwoven fabric, an apparent density of 0.225 g/ A fiber base material with a thickness of 1.45 mm formed by impregnating a cm ³ nonwoven fabric with cross-linked polycarbonate/ether polyurethane. In addition, the mass ratio of nonwoven fabric/polyurethane of the fiber base material was 90/10.
・Nylon non-woven fabric: Obtained by removing the sea component from a long-fiber sea-island composite fiber non-woven fabric, an apparent density of 0.310 g is obtained by entangling fiber bundles of 6 nylon ultrafine fibers with a single fiber fineness of 0.002 dtex. A fiber base material with a thickness of 1.3 mm formed by impregnating a cross-linked polycarbonate/ether polyurethane into a nonwoven fabric of 1.3 mm/cm ³ . In addition, the mass ratio of polyurethane/nonwoven fabric of the fiber base material was 80/20.
- PET knitted fabric: A knitted fabric of PET fiber with a single fiber fineness of 4.2 dtex, a fabric weight of 207 g/m ² , a thickness of 0.53 mm, and an apparent density of 0.391 g/cm ³ .

Further, the polyurethane solution used in this example for forming the surface resin layer will be summarized below. The solvent for each polyurethane solution was either N,N-dimethylformamide (DMF) or a mixed solvent of DMF and ethyl acetate. In addition, if necessary, about 20% by mass of pigment was blended as a solid content.

(Surface resin layer)
・20% solids solution of polycarbonate polyurethane with a 100% modulus of 3.5 MPa: S-121 manufactured by DIC Corporation
・20% solids solution of silicone-modified polycarbonate polyurethane with a 100% modulus of 7.6 MPa: DIC Corporation NY328FTR
・30% solids solution of polycarbonate polyurethane with a 100% modulus of 11 MPa: DIC Corporation MP-865PS
・30% solids solution of 100% polycarbonate polyurethane with a modulus of 20 MPa: Blend of DIC Corporation MP-865PS and DIC Corporation MP-886PS at a mass ratio of 1:1 ・100% polycarbonate polyurethane with a modulus of 29 MPa Solution with solid content of 30%: DIC Corporation MP-886PS
(Adhesive layer)
- 70% solids solution of polycarbonate polyurethane with a 100% modulus of 2.5 MPa: DIC Corporation TA205FT

The 100% modulus of each layer forming the surface resin layer was measured as follows.
Each of the above-mentioned polyurethane solutions was applied onto a smooth release paper and dried at 100° C. for 30 minutes to create a film with a thickness of about 400 μm. Then, the pieces cut out to a width of 2.5 cm were subjected to a tensile test using a universal material testing machine (Instron 5566, manufactured by Instron, USA) at 20° C. and a tensile speed of 200 mm/min. Then, the strength at 100% elongation of the obtained SS curve was read and divided by the cross-sectional area obtained from the film thickness and 2.5 cm width to obtain 100% modulus (MPa).

[Examples 1 to 8, Comparative Examples 1 to 5]
A polyurethane solution for forming a surface resin layer is applied to the surface of a textured release paper (AR-64M manufactured by Asahi Roll Co., Ltd., arithmetic mean roughness Ra of the textured surface is 95 μm) and dried at 80°C for 10 minutes. A first intermediate layer was formed as needed on the surface of the epidermal layer using the same procedure. Then, a polyurethane solution for adhesion was further applied to the surface of the formed skin layer or first intermediate layer, and dried at 50° C. for 3 minutes to form a second intermediate layer as an adhesive layer. In each of the Examples and Comparative Examples, polyurethane having a 100% modulus as shown in Table 1 was used to form each layer of the surface resin layer. Further, in Examples 2 to 5, 7, and 8 and Comparative Examples 1 to 5, the first intermediate layer was not formed.

Then, the adhesive layer of the surface resin layer formed on the surface of the textured release paper was bonded to one side of the fiber base material, and hot pressed at 80° C. for 2 minutes. In each Example and Comparative Example, the fiber base materials shown in Table 1 were used. Then, the textured release paper was peeled off from the surface resin layer. In this way, a sheet for decorative molding, which is an artificial leather having a silver-tone resin layer, was obtained.

Then, the decorative molding sheet was cut into 40 cm length x 50 cm width. Then, a preform molded body was manufactured by molding using a vacuum pressure molding machine (manufactured by Fuse Vacuum Co., Ltd., NGF-0406-T) at a mold temperature of 120° C. and a molding pressure of 300 kPa.

Then, the obtained preform molded body was placed in a cavity of a mold of an injection molding machine having a shape that conformed to the shape of the preform molded body so that the textured uneven surface was in contact with the mold surface. Then, the polycarbonate resin was injected into the mold using an injection molding machine while searching for optimal molding conditions, centering on the following conditions: resin temperature 320° C., mold temperature 25° C., and injection pressure 50 MPa. In this way, a decorative molded article having the shape of a cosmetic compact case (dome shape with a diameter of about 80 mm, a height of 10 mm, and a thickness of 3 mm) was in-mold decorated.

The obtained decorative molding sheets, preform molded bodies, and decorative molded bodies were evaluated according to the following evaluation method.

(Thickness of decorative molding sheet, resin layer and fiber base material)
Separate the surface resin layer of the decorative molding sheet from the fiber base material with a single-edged razor, take an image of the cross-sectional thickness of the surface resin layer in the thickness direction using a scanning electron microscope (SEM), and measure the thickness of each layer. was measured. Measurements were performed at five evenly selected locations, and the average value was determined.

(Average value of 100% modulus of surface resin layer)
Calculated using the following formula.
・(100% modulus of the epidermal layer x thickness of the epidermal layer) + (100% modulus of the first intermediate layer x thickness of the first intermediate layer) + (100% modulus of the second intermediate layer x 2nd thickness of the intermediate layer) / (thickness of the epidermal layer + thickness of the first intermediate layer + thickness of the second intermediate layer)

(Measurement of maximum height Rz and arithmetic mean roughness Ra of decorative molding sheet, preform molded body, and decorative molded body)
"Digital Macroscope VHX-6000" is a non-contact surface roughness/shape measuring machine that measures the surface roughness of the textured surface of the surface resin layer of decorative molding sheets, preform molded bodies, and decorative molded bodies. (manufactured by Keyence Corporation). Specifically, structured illumination light was irradiated from a high-intensity LED onto a 18 mm x 24 mm area of the textured surface of the surface resin layer, causing distortion at 50x magnification using a 4 million pixel monochrome C-MOS camera. Fringe projection images were taken. Then, the obtained image was analyzed and the maximum height Rz and arithmetic mean roughness Ra of the decorative molding sheet were calculated.

Then, the ratio of the maximum height Rz of the preform molded body and the decorative molded body to the maximum height Rz of the decorative molded sheet was calculated.

(Tactile feel of the surface of the decorative molded body)
A: Exhibited elasticity with leather-like softness.
B: Elasticity was felt, but elasticity with leather-like softness was not felt.
C: No elasticity was felt, and the feel was that of a hard resin.

(In-mold decorative moldability)
The decorative surface of the decorative molded product having the shape of a cosmetic compact case obtained by the above-described in-mold decorative molding was visually observed and evaluated according to the following criteria.
A: When molded under normal molding conditions, the warpage of the decorated molded product was small, and there were no wrinkles, distortions, or cracks in the surface resin layer.
B: When molded under normal molding conditions, wrinkles, distortion, or cracks sometimes occurred in the surface resin layer. On the other hand, by investigating the molding conditions in detail, it was possible to improve the wrinkles, distortion, cracks, and deformation of the shape of the uneven texture of the surface resin layer.
C: When molded under normal molding conditions, wrinkles, distortion, and cracks occurred in the surface resin layer, and warping occurred in the decorated molded product, so that a good product could not be obtained. In addition, even when we investigated the molding conditions in detail, we were unable to obtain a good product.

The results are shown in Table 1.

Referring to Table 1, the decorative moldings obtained in Examples 1 to 8 have a surface resin layer containing a high modulus layer with a thickness of 20 to 150 μm, which is mainly made of polyurethane with a 100% modulus of 9 to 30 MPa. When the sheet was used, the textured surface was maintained at a high rate also in the preform molded body and the decorated molded body. Furthermore, when the decorative molding sheets obtained in Examples 1 to 4, 6, and 8 were used, the in-mold decorative moldability was also excellent. In addition, when the decorative molding sheet obtained in Example 5 in which the high modulus layer was thick and the thickness ratio of the high modulus layer was high was used, the in-mold decorative moldability was slightly lowered.

On the other hand, when the decorative molding sheets obtained in Comparative Examples 1, 4, and 5 having surface resin layers that do not contain a high modulus layer are used, the preform molded body and the decorative molded body also have a textured and uneven surface. was not maintained at a high rate. Furthermore, even when the decorative molding sheet obtained in Comparative Example 2 containing a high modulus layer with a thickness of 15 μm was used, the textured surface was not maintained at a high rate even in the preform molded body and the decorated molded body. Ta. Further, when the decorative molding sheet obtained in Comparative Example 3 containing a high modulus layer with a thickness of 160 μm was used, there was no leather-like elastic feel.

1 Fiber base material 2 Second intermediate layer (adhesive layer)
3 First intermediate layer 4, 14 Skin layer 5, 15 Surface resin layer 7 Decorated molded object (resin molded object)
10, 20 Decorative molding sheet 12 Intermediate layer (adhesive layer)
30, 30a Preform molded body 40 Decorated molded body

Claims (7)

A decorative molding sheet comprising a fiber base material and a surface resin layer including at least one resin layer laminated and bonded to one surface of the fiber base material,
The surface resin layer is mainly made of polyurethane,
The surface has a textured texture,
having a total thickness of 70 to 200 μm,
A decorative molding sheet comprising a high modulus layer having a 100% modulus of 9 to 30 MPa at 20° C. and a thickness of 20 to 150 μm. The decorative molding sheet according to claim 1, wherein the surface resin layer has an average 100% modulus of 9 to 30 MPa. The surface resin layer includes a skin layer disposed on the surface and at least one intermediate layer not disposed on the surface, and the high modulus layer is at least one of the skin layer or the intermediate layer. The decorative molding sheet according to claim 1 or 2. The sheet for decorative molding according to any one of claims 1 to 3, wherein the thickness ratio of the high modulus layer in the surface resin layer is 20 to 80%. The decorative molding sheet according to any one of claims 1 to 4, wherein the maximum height Rz of the textured unevenness is 60 to 120 μm. A preform molded article, characterized in that the decorative molding sheet according to any one of claims 1 to 5 is shaped into a three-dimensional shape. A decorated molded article comprising a decorated molded article and a decoration layer that decorates the surface of the decorated molded article,
A decorative molded article, wherein the decorative layer contains the decorative molding sheet according to any one of claims 1 to 5.