JP5861296B2 - Decorative sheet - Google Patents

Description

  The present invention relates to exterior materials for buildings such as houses, building materials such as construction materials and fittings, furniture and fixtures, exterior materials such as housing equipment and home appliances, and vehicle exterior materials such as automobiles. More particularly, the present invention relates to a decorative sheet used as a door material for a house entrance and the like that requires both flexibility and weather resistance to self-repair surface scratches and dents.

  Conventionally, as a decorative sheet for such use, a sheet obtained by printing an appropriate pattern on a polyvinyl chloride resin film has been mainly used. In recent years, taking into account environmental issues, there has been a switch to decorative sheets that use non-chlorine resin films such as polyolefin resins that do not cause the generation of harmful substances such as hydrogen chloride or dioxin during combustion. Progressing.

  By the way, the decorative sheet for such use is required to have good suitability for secondary processing such as lapping. In recent years, there has been an increase in cases where it is required to have a self-healing property of a wound by elastically receiving a scratch such as a scratch. As a means for responding to this demand, there is a method in which a highly flexible resin having a low glass transition point is used for the surface protective layer to impart easy processability and self-healing property of scratches.

  However, resins with a low glass transition point are prone to bleed additives due to their properties, and it is difficult to sufficiently add weathering agents. Use them for parts that require high weather resistance, such as housing exterior materials. Is difficult.

JP 2004-322339 A

  The present invention has been made to solve such problems. That is, the object of the present invention is to provide a decorative sheet having high weather resistance as well as easy processability and self-healing ability of scratches. .

The present invention solves this problem. That is, the invention according to claim 1 is a decorative sheet having at least a base sheet, a pattern layer, an anchor coat layer, and a surface protective layer in this order. There will as a main component an acrylic resin composition, a glass transition point of the surface protective layer becomes 10 to 50 ° C., the glass transition point of the anchor coat layer is higher than the glass transition point of the surface protective layer, and 100 ° C. The decorative sheet is characterized by comprising 10 to 30 parts by weight of an ultraviolet absorber with respect to 100 parts by weight of the resin component constituting the anchor coat layer.

According to the invention of the first aspect, the present invention has an anchor coat layer having a glass transition point higher than that of the surface protective layer below the surface protective layer, and 100 parts by weight of the resin component of the anchor coat layer. In addition, 10 to 30 parts by weight of an ultraviolet absorber, a weathering agent that cannot be retained due to bleed phenomenon with a resin having a low glass transition point for the purpose of flexibility, easy processability and self-healing was held in the anchor coat layer, the weathering adhesion weathered prevention and surface protective layer of the printed ink layer is improved, has high weather resistance along with self-healing of the wound surface, to have a processing suitability decorative sheet It became possible to get.

It is explanatory drawing which shows the structure of the cross section of one Example of the decorative sheet of this invention.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 shows a cross-sectional structure of one embodiment of the decorative sheet of the present invention. A pattern layer 2, an anchor coat layer 3, and a surface protective layer 4 are provided on the base sheet 1 in this order.

  The substrate sheet 1 in the present invention is not particularly limited as long as it can be provided with a pattern layer 2 to be described later, and has a performance as a substrate of a decorative sheet. Can be used. In particular, in consideration of dealing with environmental problems, non-chlorine-based resin films such as polyolefin-based resins that do not cause the generation of harmful substances such as hydrogen chloride or dioxin during combustion are preferably used.

  The polyolefin resin is not particularly limited. For example, polyethylene such as low density polyethylene, medium density polyethylene, high density polyethylene, and linear low density polyethylene; polypropylene; ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer Examples thereof include ethylene polymers such as polymers and ethylene-α-olefin copolymers, and those obtained by mixing elastomers such as styrene resins with these olefin resins. Moreover, you may be comprised using the mixed resin which mixed multiple types of different olefin resin uniformly, and what laminated | stacked the sheet | seat which consists of a different olefin resin may be sufficient. The layer thickness is preferably about 50 to 150 μm.

  The base sheet 1 may contain a pigment or the like as a colorant and can be appropriately selected depending on the purpose. For example, azo, phthalocyanine, selenium, dye lake, quinacridone, Organic pigments such as dioxazines; various inorganic pigments such as oxides such as titanium oxide described above, chromic molybdates, sulfides / selenides, ferrocyanides, and calcium carbonate can be used as appropriate. By containing these pigments in the olefin-based resin base sheet, the color of the adherend can be concealed and the saturation of the colored coating layer can be improved. In this case, a white pigment is desirable for concealing the color of the adherend and improving the saturation of the colored coating layer, and titanium oxide is particularly preferably used.

  Furthermore, other additives may be added to the base sheet 1 as long as the sheet moldability and sheet physical properties are not impaired, and examples thereof include a light stabilizer, an ultraviolet absorber, and a heat stabilizer.

  As the pattern / pattern layer 2 in the present invention, the contents of the pattern / pattern layer, such as the formation method, material, and pattern of the pattern / pattern layer, are not particularly limited. The pattern layer is usually formed using ink by a conventionally known printing method such as gravure printing, silk screen printing, offset printing, gravure offset printing, and ink jet printing. The pattern is, for example, a wood grain pattern, a stone pattern, a grain pattern, a cloth pattern, a tile tone pattern, a brick tone pattern, a crest pattern, a character, a symbol, a geometric pattern, or a combination of two or more of these. . Moreover, you may give weatherproof prescriptions, such as a ultraviolet absorber and a light stabilizer.

  As the anchor coat layer 3 in the present invention, a material having a glass transition point higher than that of the surface protective layer 4 described later and containing 10 to 30 parts by weight of an ultraviolet absorber with respect to 100 parts by weight of the resin component is used. Since the glass transition point of the surface protective layer to be described later is 10 to 50 ° C., a glass transition point higher than that may be used, but if the glass transition point is higher than 100 ° C., the workability deteriorates. C. or lower is preferred. When the ultraviolet absorber is less than 10 parts by weight, sufficient weather resistance is not exhibited, and when it is more than 30 parts by weight, problems such as a decrease in adhesion to the surface protective layer and a cost problem occur. As the resin used for the anchor coat layer, acrylic polyol, vinyl chloride / vinyl acetate copolymer, a mixture thereof and the like are suitable.

  As the surface protective layer 4 in the present invention, one having an acrylic resin composition as a main component and a glass transition point of 10 to 50 ° C. is used. As the resin to be used, for example, an acrylic acid derivative such as any known acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid, acrylic ester or methacrylic ester which has been conventionally used as a surface layer for a decorative sheet is mainly used. Examples of the component include various thermoplastic resins obtained by single or copolymerization. Among them, a resin mainly composed of a methacrylic acid ester such as methyl methacrylate, for example, a long-chain alkyl ester of methacrylic acid such as butyl methacrylate, an acrylic acid ester such as methyl acrylate, methacrylic acid or acrylic acid, etc. Add selected monomers as copolymer components or improve the flexibility and thermoformability by graft copolymerization, block copolymerization or blending of rubber components such as styrene-butadiene rubber or methyl methacrylate-butadiene rubber Thus, the resin etc. which are formed can be used conveniently.

  In the present invention, an extruded resin layer or a transparent resin layer is appropriately provided between the pattern layer 2 and the surface protective layer 4 by bonding or the like for reasons of design and strength in addition to the anchor coat layer 3. There is no particular limitation.

  A 70 μm thick homopropylene resin colored sheet (“Rivester TPO” manufactured by Riken Technos Co., Ltd.) is used as the base sheet 1, and this is subjected to wood grain printing using a two-component urethane resin binder ink on a gravure printing machine, and a pattern layer 2 was provided. A transparent random polypropylene resin (extrusion thickness 60 μm) and an elastomer resin (extrusion thickness 10 μm) were provided as a transparent resin layer on the design pattern layer by coextrusion lamination so that the elastomer resin side was in contact with the design pattern layer 2.

  After the corona treatment on the surface of the transparent resin layer, 80 parts by weight of a methyl methacrylate monomer and 20 parts by weight of a cyclohexyl methacrylate monomer are copolymerized as an anchor coat layer 3 and an unsaturated alcohol is added to impart a hydroxyl group to the side chain. 10 parts by weight of a hydroxyphenyltriazine ultraviolet absorber (“Tinuvin 400” manufactured by Ciba Japan Co., Ltd.) and a benzotriazole ultraviolet absorber (Ciba The main agent solution (5 parts by weight of UV absorber: 15 parts) added with 5 parts by weight of “Tinuvin 1130” manufactured by Japan Co., Ltd. and hexamethylene diisocyanate type curing agent were mixed at a ratio of 10: 1. The coating solution was applied to a thickness of 6 μm. The glass transition point was 100 ° C.

  On the anchor coat layer 3, as a surface protective layer 4, an acrylic acrylate resin having a glass transition point of 30 ° C. (“TP-1” manufactured by NATCO Co., Ltd.) is applied to a thickness of 15 μm, and a decorative sheet is prepared. Obtained.

<Comparative Example 1>
A decorative sheet was obtained in the same manner as in Example 1 except that the ultraviolet absorber added to the anchor coat layer 3 was added to the surface protective layer 4 instead of being added to the anchor coat layer 3.

<Comparative Example 2>
In Example 1, the addition amount of the UV absorber was 5 parts by weight of the hydroxyphenyltriazine UV absorber and 2.5 parts by weight of the benzotriazole UV absorber (total UV absorber part: 7.5 parts). Other than that, a decorative sheet was obtained in the same manner as in Example 1.

<Comparative Example 3>
In Example 1, the amount of the UV absorber added was 30 parts by weight of the hydroxyphenyltriazine UV absorber and 15 parts by weight of the benzotriazole UV absorber (total 45 parts by weight of UV absorber). A decorative sheet was obtained in the same manner as in Example 1.

<Surface protective layer adhesion>
The decorative sheet thus obtained was subjected to a cello tape (registered trademark) peel test after cross-cutting the surface protective layer. It was confirmed whether peeling of the surface protective layer occurred.

<Confirmation of presence or absence of bleed of weathering agent>
The decorative sheet thus obtained was cured in a constant temperature bath at 40 ° C. for 48 hours and then allowed to stand at room temperature (25 ° C.) for a maximum of one month, and observation was made as to whether or not the weathering agent bleed phenomenon occurred. .

<Weather resistance>
The decorative sheet thus obtained was subjected to a weather resistance test using a die plastic / metal weather tester. The test conditions for the weather resistance test are shown below.
Testing machine: Daipla Metal Weather (model: KU-R5DC1-A manufactured by Daipura Wintes Co., Ltd.)
Test conditions: 1 cycle = Light (illuminance 70 mW / cm 2, temperature 53 ° C., humidity 50% RH) 20 hours
+ Dew (temperature 30 ° C, humidity 95% RH) 4 hours (shower back and forth 30 seconds)
+ Rest (temperature 30 ° C., humidity 95% RH) 0.01 hours
This cycle test was repeated up to 21 cycles.
Evaluation method: (1) Confirmation of design / fading, white turbidity, or significant embrittlement
(2) Weather-resistant adhesion of surface protective layer / Cross fan tape peel test after cross-cutting the surface protective layer. Check if the surface protective layer peels off.
(1) Evaluation is made based on the number of repetitions when NG occurs in any of (2) (the weather resistance performance is higher as the number of repetitions is larger).
The results are shown in Table 1.

  By adopting as in Example 1, there is no fear of migration of additives such as bleed even when a highly flexible resin having a low glass transition point is selected as the surface protective layer, and sufficient weather resistance that can withstand use in exterior applications. It is possible to obtain sex.

  The decorative sheet of the present invention can be used as a door material for a house entrance that requires both flexibility and weather resistance to self-repair surface scratches and dents.

DESCRIPTION OF SYMBOLS 1 ... Base material sheet 2 ... Pattern pattern layer 3 ... Anchor coat layer 4 ... Surface protective layer

Claims (1)

In a decorative sheet having at least a base sheet, a pattern layer, an anchor coat layer, and a surface protective layer in this order,
The surface protective layer is mainly composed of an acrylic resin composition,
The glass transition point of the surface protective layer is 10 to 50 ° C. ,
The glass transition point of the anchor coat layer is higher than the glass transition point of the surface protective layer and is 100 ° C. or less,
A decorative sheet comprising 10 to 30 parts by weight of an ultraviolet absorber with respect to 100 parts by weight of a resin component constituting the anchor coat layer.