JP2005119020A - Decorative sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a decorative sheet capable of suppressing the whitening phenomenon caused by the cracking, elongation or the like of a protective layer in bending processing and excellent in scratch resistance and abrasion resistance. <P>SOLUTION: In the decorative sheet wherein the protective layer based on a transparent or translucent resin composition is provided on the surface of a base material, the glass transition point of the resin of a lower layer is lower than that of the resin of an upper layer and the resin of the lower layer has a glass transition point of -5 to 30°C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a decorative sheet for use in surface makeup such as interior materials and construction materials for buildings such as houses, decorative steel sheets, building materials such as joinery, furniture fixtures, construction equipment, and home appliances. In particular, it is often applied to steel sheets such as entrance doors and sashes and is bent, and it is related to a durable decorative sheet that can maintain wear resistance, scratch resistance, and contamination resistance over a long period of time. Is.

  When vinyl chloride, olefin resin, etc. are used as a decorative sheet, as a protective layer to improve the surface design and physical properties, the resin is not used as the outermost layer, but the top coat is protected on the surface. Often used as a layer.

  In many applications, it is often bonded to steel plates and non-combustible substrates such as MDF and plywood, slate plates, and calcium plates. In many cases, bending is performed, and a steep bending angle is required with the recent high design.

  However, when the folding process is performed above a certain level, there is a problem that the protective layer of the decorative sheet laminated on the steel sheet cannot follow the bending and causes whitening due to cracking, elongation, and the like.

Prior art document information.
Japanese Patent Laid-Open No. 4-93245 JP 2000-102948 A JP 2001-079989 A JP 2001-287314 A

  To obtain a cosmetic material that can suppress whitening phenomena such as cracking and elongation of the protective layer in bending and the like, and has excellent scratch resistance and abrasion resistance.

  In a decorative sheet in which a protective layer mainly composed of a transparent or translucent resin composition is provided on the surface of a base material, a resin having a lower glass transition point than that of the upper resin layer is used. A decorative sheet characterized by being used.

  The decorative sheet, wherein the lower layer resin has a glass transition point in the range of -5 ° C to 30 ° C.

  By forming a relatively hard resin layer on the upper layer of the surface protective layer and a soft resin layer of -5 ° C to 30 ° C on the lower layer, whitening phenomena such as cracking and elongation of the protective layer in bending work can be suppressed. And a decorative material characterized by excellent scratch resistance and abrasion resistance.

  In the present invention, the material and configuration of the base material 1 are not particularly limited, and any base material for general cosmetics can be applied. Specifically, for example, paper such as thin paper, titanium paper, fine paper, surface-treated paper, resin-impregnated paper, resin-mixed paper, inter-paper reinforced paper, fiber materials such as woven fabric or nonwoven fabric, polyolefin-based materials, Polyester-based, acrylic-based, polystyrene-based, polyamide-based, polyvinyl-based thermoplastic resin films and molded products, synthetic resin-based substrates such as fiber-reinforced plastic, wood-based substrates such as wood veneer, plywood, laminated wood, An inorganic base material, a metal base material, etc., or these multiple types of composites, laminates, etc. can be arbitrarily employed depending on the intended use of the cosmetic material.

  The material used for the protective layer can be appropriately selected from polyurethane, acrylic, acrylic silicon, fluorine, epoxy, vinyl, polyester, melamine, aminoalkyd, urea, and the like. Also, any of water, emulsion, solvent and the like can be used, and the curing method may be thermosetting type, photocuring type and active energy ray curing type.

  The protective layer 1 protects from wear and scratches over time in use and protects it over a long period of time, and an acrylic system is often used to enhance its effect.

  In general, when acrylic or the like having a glass transition point of around 100 ° C. is used for the protective layer of the surface layer, it tends to cause a whitening phenomenon when bent, but by constituting the resin layer of the present invention described below as a lower layer, As a decorative material, it can have bending workability while maintaining surface hardness and wearability.

  For the protective layer 2, a resin having a glass transition point in the range of −5 ° C. to 30 ° C. is used. Even if a relatively hard acrylic material is used for the outermost protective layer 1, combining the protective layer 2 with flexibility makes the surface hardness and wear resistance the same while having unprecedented bending workability. I can get it.

  On the other hand, if the thickness of the protective layer 2 is too thin, it is difficult to obtain a sufficient effect of flexibility, it becomes easy to break, and the appropriateness of secondary processing such as bending, V-cut processing and lapping processing is lowered. On the other hand, if it is too thick, it is easy to dent as a cosmetic material, and it is difficult to obtain scratch resistance and surface hardness.

  It is desirable that the film thickness of the protective layer 2 be 3 to 6 μm within the range of the present inventors' tests.

  The resin composition that is the main component of the protective layer 2 is not merely required to be soft, but also requires moderate hardness. From such a viewpoint, it is desirable to use a reaction product of an acrylic polyol and an isocyanate compound, that is, an acrylic urethane resin, which has an excellent balance between hardness and flexibility.

  As a method for forming the protective layer, for example, gravure coating, roll coating, rod coating, kiss coating, knife coating, air knife coating, die coating, lip coating, spray coating, flow coating, silk printing, offset printing, gravure printing and the like are conventionally known. It can depend on any coating method. In particular, if the substrate 1 is a continuous winding shape such as paper or a thermoplastic resin film, the one by gravure printing is generally used.

  Examples of the present invention and comparative examples are shown below.

-Preparation of substrate-
A colored polypropylene resin film having a thickness of 100 μm is used as a lower base sheet, and a woodgrain pattern pattern layer is printed on the surface thereof with urethane-based ink, and a two-part curable urethane adhesive is used as an upper base surface sheet with a thickness of 80 μm A transparent polypropylene resin film was laminated and its surface was embossed with a conduit handle.

-Example-
An acrylic protective layer 1 having a glass transition point of about 100 ° C. is applied to the surface layer of the substrate, and an acrylic urethane protective layer 2 having a glass transition point of about 5 ° C. is applied and cured under the gravure coating method. A decorative sheet was prepared.

-Comparative example-
In the said Example, the decorative sheet was produced as a protective layer using the acrylic layer whose glass transition point is about 50 degreeC for the said protective layer 2. FIG.

-Performance comparison-
The decorative sheet prepared above was bonded to a 0.5 m / m thick stainless steel plate to make a decorative plate. The decorative plate surface was (1) bent to 90 ° C., and (2) a coin scratch test in which a 10-yen coin was rubbed with a load of 1 kg, and the protective layer was evaluated for cracking, whitening, and scratch resistance.

-List of evaluation results-

Bending whitening Coins scratch test <br/> Example ○ ○
Comparative example

1 shows an embodiment of a decorative sheet of the present invention.

Explanation of symbols

1 Base material 2 Protective layer 1
3 Protective layer 2

Claims (2)

  In a decorative sheet in which a protective layer mainly composed of a transparent or translucent resin composition is provided on the surface of a base material, a resin having a lower glass transition point than that of the upper resin layer is used. A decorative sheet characterized by being used.   The decorative sheet, wherein the lower layer resin has a glass transition point in the range of -5 ° C to 30 ° C.

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