JP2010201740A - Decorative sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a decorative sheet which is reduced in a use ratio of a fossil resource-derived material while having designability equal to conventional ones. <P>SOLUTION: The decorative sheet includes at least a colored thermoplastic resin layer and a pattern ink layer, wherein lignin is contained, as a coloring agent, in the colored thermoplastic resin layer. Thus, the lignin, for which an effective use method other than the method using as energy is asked, can be effectively used as a coloring agent of a decorative sheet base material, and besides, the use ratio of the fossil resource-derived material in the decorative sheet can be reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a decorative sheet mainly composed of a thermoplastic resin among decorative sheets used mainly for surface decoration of building members such as doors and frames of buildings.

  In recent years, a decorative sheet mainly composed of a thermoplastic resin has been used mainly as a surface decoration for building members such as doors and frames of buildings. As such a resin-based decorative sheet, a decorative sheet having a single-layer configuration in which a pattern is printed on the front side or the back side of a thermoplastic resin film substrate, and a pattern layer printed on the thermoplastic resin film substrate. Further, there is a decorative sheet having a multilayer structure in which a transparent resin layer is laminated.

  As a constituent material for the film base of the decorative sheet and the transparent resin layer, conventionally, a polyvinyl chloride resin which is inexpensive and excellent in processability and physical properties has been frequently used. However, polyvinyl chloride resin may generate harmful chlorine compounds when discarded or incinerated. In recent years, decorative sheets using polyolefin resin, polyester resin, etc. have been proposed (Patent Documents 1 and 2). reference). If it is a decorative sheet made of these resin systems, no harmful gas is generated even if incinerated, and the burden on the environment can be reduced.

  However, in recent years, there has been a demand for reduction of carbon dioxide in the atmosphere, saving of fossil resources such as oil, and use of plant-derived materials. The decorative sheet is no exception, and there is a demand for reducing fossil resource-derived materials such as polyolefin resins and polyester resins.

Japanese Patent Laid-Open No. 6-79830 Japanese Patent Laid-Open No. 7-24979

  The present invention has been made in order to solve the above-mentioned problems, and the object of the present invention is to provide a decorative sheet that has a design equivalent to that of the prior art and has a reduced use rate of fossil resource-derived materials. There is.

  The present invention solves the above-mentioned problem, that is, the invention according to claim 1 is a decorative sheet comprising at least a colored thermoplastic resin layer and a pattern ink layer, and a colorant in the colored thermoplastic resin layer. It is a decorative sheet characterized by containing lignin.

  Lignin is particularly abundant in wood and varies depending on the type of wood, but its content is approximately 20 to 30% by weight based on the total components of wood. Lignin is generated in large quantities, particularly in the pulp manufacturing process. That is, in the pulp manufacturing process, wood chips are digested with a chemical solution containing sodium hydroxide and sodium sulfide, and the pulp made of wood fibers is recovered, but the concentrated waste liquid after pulp recovery is called black liquor. Contains lignin. Lignin can be easily obtained by neutralizing black liquor with acid (the lignin thus obtained is referred to as kraft lignin), but black liquor is generally burned in a recovery boiler in pulp manufacturing plants. Currently, lignin is used as energy, and there is a demand for an effective use method other than energy.

  According to the first aspect of the present invention, lignin can be effectively used as a colorant for a decorative sheet substrate, and the use ratio of a fossil resource-derived material in the decorative sheet can be reduced.

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

  Hereinafter, embodiments of the present invention will be described in detail. As shown in FIG. 1, the most basic configuration of the present invention is a laminate in which a pattern ink layer 2 is laminated on a colored thermoplastic resin layer 1.

  The colored thermoplastic resin layer 1 serves as a base material for the decorative sheet, and the thermoplastic resin used can be arbitrarily selected in consideration of the price and ease of use. Polyolefin resins such as polypropylene and polyethylene are particularly suitable, but other examples include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, ethylene vinyl acetate copolymer, ethylene vinyl alcohol copolymer, polystyrene, ABS. Polymethyl methacrylate, polymethyl acrylate, polybutyl acrylate, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl acetal, polyurethane, polyamide, nylon and the like can also be used. If necessary, these materials may be combined to form a multilayer.

  The present invention is characterized in that the colored thermoplastic resin layer 1 contains lignin as a colorant. The lignin used is not particularly limited, but the kraft lignin described above is most convenient. Further, since the decorative sheet generally has a wood grain pattern, the colored thermoplastic resin layer 1 is usually colored in a brown color. However, since kraft lignin has a dark brown color, the brown color is changed. Suitable for expressing. The amount of lignin added to the colored thermoplastic resin layer 1 can be appropriately adjusted to obtain a desired color, and is not particularly limited. Further, various known pigments may be added to the colored thermoplastic resin layer 1 in addition to lignin, and the color and blending ratio are arbitrarily determined in view of the degree of concealment, design properties, etc. There are no restrictions.

  As a manufacturing method of the colored thermoplastic resin layer 1, known film forming methods such as a T-die extrusion method and a calendar method can be used. Coloring methods include dry color method using fine powder colorant obtained by treating lignin and other pigments with dispersing aid or surfactant, and melt kneading thermoplastic resin with high concentration of lignin and other pigments. There is no particular limitation, such as a master batch method in which pre-dispersed master batch pellets are prepared and dry blended with a thermoplastic resin not colored in the hopper.

  The pattern ink layer 2 is provided to impart a design such as a wood grain pattern to the decorative sheet, or to conceal the colored thermoplastic resin layer 1 by solid coloring. As a method for forming the pattern ink layer 2, the colored thermoplastic resin layer 1 is formed using a known printing technique such as gravure printing, offset printing, intaglio printing, screen printing, flexographic printing, silk printing, electrostatic printing, and ink jet printing. Although it is common to print on the surface, it is not necessarily limited to this. Ink used is also known, that is, a colorant such as a dye or pigment, an extender is added to the vehicle, and a plasticizer, stabilizer, wax, grease, desiccant, curing agent, thickener, dispersant. In addition, a filler or the like may be arbitrarily added and sufficiently diluted with a solvent, a diluent or the like and stirred.

  In the present invention, a transparent resin layer 3 may be appropriately laminated on the pattern ink layer 2 as shown in FIG. Examples of the purpose of providing the transparent resin layer 3 include improving the design of the decorative sheet, protecting the pattern ink layer 2, imparting surface wear resistance, chemical resistance, scratch resistance, and weather resistance. As a material used for the transparent resin layer 3, polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, ethylene vinyl acetate copolymer, ethylene vinyl alcohol copolymer, polystyrene, ABS, polymethyl methacrylate, Thermoplastic resins such as polymethyl acrylate, polybutyl acrylate, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl acetal, polyurethane, polyamide, and nylon can be used, among which polypropylene or polyethylene terephthalate is preferred. . An ultraviolet absorber, a light stabilizer, a heat stabilizer, a flame retardant, an antiblocking agent and the like can be added to the transparent resin layer 3 as necessary.

  As a method of laminating the transparent resin layer 3 on the pattern ink layer 2, a heat lamination method in which heat and pressure are applied, a dry lamination method or a wet lamination method in which bonding is performed using an adhesive, and the transparent resin layer 3 are used. In addition to the extrusion lamination method in which the resin is bonded while being melt-extruded from a T die, there are methods such as a knee lamination method and a sand lamination method, which may be appropriately selected depending on the resin used for the transparent resin layer 3. For example, when polypropylene is used as the transparent resin layer 3, an extrusion lamination method or a dry lamination method is preferable, and when polyethylene terephthalate is used, a dry lamination method is preferable.

  In addition, the surface protective layer 4 may be appropriately laminated as necessary. The material of the surface protective layer 4 is not particularly defined as long as sufficient adhesion to the transparent resin layer 3 is obtained in addition to various physical properties such as weather resistance, abrasion resistance, scratch resistance, and chemical resistance. , Urethane resin, acrylic resin, polyester resin and the like. The curing method can also be appropriately selected from a one-component curing type, a two-component curing type using a curing agent, a curing type by active energy ray irradiation, and the like. Moreover, you may add various additives, such as a ultraviolet absorber, a light stabilizer, a heat stabilizer, a lubricant, a flame retardant, an antiblocking agent, to the surface protective layer 4 as needed. The thickness of the surface protective layer 4 is preferably 3 to 15 μm. As a method of providing the surface protective layer 4, various known coating methods such as gravure coating, reverse coating, gravure reverse coating, die coating, and flow coating can be used.

  In addition, in order to improve the adhesion strength between the decorative sheet of the present invention and the wooden board, inorganic board, metal plate or the like, the primer layer 5 is provided on the back surface of the colored thermoplastic resin layer 1 as necessary. May be provided. With respect to this primer layer 5, sufficient adhesion strength with the colored thermoplastic resin layer 1 has been obtained, and adhesion with an adhesive used when laminating with wooden boards, inorganic boards, metal plates, etc. The material is not particularly defined as long as the property is obtained, but it is preferable to use a polyurethane-based material.

  As a colorant used for the colored thermoplastic resin layer 1, 10 parts by weight of kraft lignin, 20 parts by weight of titanium dioxide, 30 parts by weight of calcium carbonate, and 40 parts by weight of polypropylene resin were melt-kneaded to prepare master batch pellets. A colored thermoplastic resin layer 1 having a thickness of 70 μm was obtained by extruding a film from a T die at 250 ° C. while dry blending 50 parts by weight of the master batch pellets and 50 parts by weight of a polypropylene resin in a hopper. On the colored thermoplastic resin layer 1, a wood grain pattern was applied as a pattern ink layer 2 by a gravure printing method.

  A two-component curable anchor coating agent obtained by mixing 80 parts by weight of urethane-modified polyester polyol, 10 parts by weight of hexamethylene diisocyanate and 10 parts by weight of isophorone diisocyanate on the pattern ink layer 2 using a gravure coating method. It apply | coated so that it might become 1 micrometer. Subsequently, a transparent homopolypropylene resin is laminated by extrusion laminating so as to have a thickness of 80 μm to form a transparent resin layer 3. ]) Was applied to a thickness of 6 μm to obtain a decorative sheet of the present invention.

  The decorative sheet obtained as described above has an excellent design and effectively uses lignin, which is a plant-derived material.

  INDUSTRIAL APPLICABILITY The present invention is particularly applicable to a decorative sheet mainly composed of a thermoplastic resin among decorative sheets mainly used for surface decoration of building members such as doors and frames of buildings.

DESCRIPTION OF SYMBOLS 1 ... Colored thermoplastic resin layer 2 ... Pattern ink layer 3 ... Transparent resin layer 4 ... Surface protective layer 5 ... Primer layer

Claims (1)

  A decorative sheet comprising at least a colored thermoplastic resin layer and a pattern ink layer, wherein the colored thermoplastic resin layer contains lignin as a colorant.