JPH1120109A - Decorative sheet - Google Patents

Abstract

(57) [Problem] To provide a formaldehyde trapping function in a decorative sheet having a formaldehyde trapping function comprising a two-component curable polyurethane resin for a protective layer and an organic network compound for a formaldehyde trapping layer. It is an object of the present invention to provide a decorative sheet having a decorative sheet and having excellent friction and chemical properties on the surface of the decorative sheet. SOLUTION: In a laminate comprising a protective layer, a picture layer, a formaldehyde trapping layer, a shielding layer and a paper substrate, the outermost surface layer of the laminate comprises the protective layer, and between the protective layer and the formaldehyde trapping layer. A decorative sheet, wherein the shielding layer is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a decorative sheet used for interior decoration of buildings, surface decoration of fittings, furniture such as cupboards and chests, and the like.

[0002]

2. Description of the Related Art Conventionally, a decorative sheet of this type generally uses paper as a substrate, and a printed sheet formed by printing on the paper is used as it is, and is used by being bonded to the surface of an adherend. I have. However, many adherends to which a decorative sheet is attached are formed using a material that generates formaldehyde. For example, a formaldehyde-generating substance such as a urea resin is used for an adhesive for forming a wood plywood, a particle board, a wood fiber board, or the like, a resin constituting the FRP, or a resin constituting the resin base itself. Therefore, if a printing sheet is directly stuck to such an adherend, formaldehyde is released into a room or the like, which impairs the indoor sanitary environment.

[0003]

Therefore, for these adherends, use is made of a resin containing no formaldehyde, such as a vinyl acetate resin, or a formaldehyde scavenger comprising an organic amino compound is added to the resin. However, there is a problem that the adhesive strength between layers is insufficient (especially the initial adhesive strength is weak) in the case of plywood because the resin not containing formaldehyde has low adhesive strength. In the case of particle board, wood fiber board, and FRP, there is a problem that physical properties such as strength are changed.
Further, when the formaldehyde scavenger is used by adding it to the adherend itself, there is a problem that the price is increased and the physical properties of the finished product may be changed.

[0004] The present invention has been made in view of the above problems, and an object of the present invention is to provide a decorative sheet having a harmful formaldehyde trapping function. Further, a typical substance having a formaldehyde trapping action is an organic amino compound, and usually, a decorative sheet having a formaldehyde trapping function is formed with a formaldehyde trapping layer containing these substances.
The formaldehyde trapping layer is designed to trap formaldehyde released from an adherend or the like.

On the other hand, a decorative sheet is usually provided with a decorative layer such as a wood grain pattern, a solid pattern, or an abstract pattern, and a protective layer is provided to protect the decorative layer and to improve the friction and chemical properties of the decorative sheet surface. Although provided, the protective layer reacts by adding a curing agent having an isocyanate group to a main agent having a polyol group from the viewpoint of processability, cost and performance.
Liquid-curable polyurethane-based resins are widely used. In addition, a two-component curable urethane-based resin may be used for the decorative layer in order to improve the adhesiveness to the paper substrate.

However, a decorative sheet having a protective layer formed of the two-component curable polyurethane resin and a formaldehyde trapping layer formed of an organic amino compound is produced at the time of production. Isocyanate and an amine of an organic amino compound react to form a urethane monomolecule, thereby eliminating the function of trapping formaldehyde and forming a protective layer. A problem arises in that the friction and chemical properties of the surface do not reach the desired resistance.

Accordingly, the present invention has been made in view of the above-mentioned problems, and has as its object the following:
Using a two-component curable polyurethane resin for the protective layer, and
In a decorative sheet having a formaldehyde trapping function comprising an organic amino compound in the formaldehyde trapping layer, the reaction between the isocyanate of the two-component curable polyurethane resin used in the protective layer and the amine of the organic amino compound used in the formaldehyde trapping layer is performed. An object of the present invention is to provide a decorative sheet having a formaldehyde trapping function, and having excellent friction and chemical properties on the surface of the decorative sheet.

[0008]

To achieve the above object, the decorative sheet according to the first aspect of the present invention is a decorative sheet comprising a protective layer, a picture layer, a formaldehyde capturing layer, a shielding layer and a paper substrate. The outermost layer of the laminate is formed of the protective layer, and the shielding layer is formed between the protective layer and the formaldehyde trapping layer. By providing the shielding layer in this way, it is possible to prevent the protective layer and the formaldehyde trapping layer from coming into direct contact, and to use a two-component curable polyurethane resin for the protective layer, and to use the formaldehyde trapping layer. Also, in the configuration using an organic amino compound, isocyanate, which is a curing agent for the two-component curable polyurethane resin of the protective layer, and amine of the organic amino compound provided in the formaldehyde trapping layer are mutually transferred by the shielding layer. It is possible to provide a decorative sheet having a formaldehyde trapping function and excellent friction and chemical properties on the surface of the decorative sheet.

The decorative sheet according to the second aspect of the present invention is a laminate comprising a protective layer, a picture layer, a paper substrate and a shielding layer, wherein the outermost layer of the laminate comprises the protective layer and the picture layer. A layer containing a formaldehyde trapping substance, wherein the shielding layer is formed at least between the protective layer and the picture layer. By adopting such a configuration, it is not necessary to provide a separate formaldehyde capturing layer, so that the number of steps and the cost are reduced.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail below with reference to the drawings and the like. 1 to 6 are cross-sectional views showing the layer configurations of the first to sixth embodiments of the decorative sheet of the present invention, in which 1 is a protective layer, 2, 2 ′ are picture layers, 3, 3 ′,
3 "is a paper substrate, 4 is a formaldehyde trapping layer, 5 is a shielding layer, 6, 6 'is an adhesive layer, and 10, 10' are decorative sheets.

FIG. 1 is a sectional view showing a layer structure of a decorative sheet according to a first embodiment of the present invention. The decorative sheet 10 includes a protective layer 1, a picture layer 2, a shielding layer 5, a formaldehyde trapping layer 4, and paper. The bases 3 are sequentially stacked. As the paper forming the paper base 3, high-quality paper, tissue paper, Japanese paper, kraft paper, titanium paper, linter paper, paperboard, gypsum board paper, or the like is used, and its basis weight is suitably ²⁰ to 80 g / m ² . is there. Further, the paper substrate 3 may be any of these papers alone or a laminate of two or more layers. This paper substrate 3
Formaldehyde trapping layer 4 for trapping formaldehyde by applying a coating liquid containing a substance that traps formaldehyde to the surface by a well-known roll coating method, gravure coating method, or the like.
Are formed. In this case, it is obvious that the formaldehyde trapping layer 4 is also formed in the paper layer of the paper substrate 3.

A typical substance that traps formaldehyde is an organic amino compound, which reacts easily with formaldehyde, and its product does not dissociate formaldehyde and is a harmless and stable substance. , Ethylene urea, propylene urea, 5-hydroxypropylene urea, 5-methoxypropylene urea, 5-methylpropylene urea, parabanic acid (glyoxal monourene), 4,5-dimethoxyethylene urea, pyrrolidine, piperidine, formolin, 2- Examples thereof include hydrazobenzothiazole or derivatives thereof, amines such as dicyandiamide, amides, and imides. Further, ammonium hydroxide may be added as needed. Further, the formaldehyde-trapping substance is silica, talc,
It may be supported on an inorganic powder such as clay, activated carbon, zeolite, and sepiolite.

The coating liquid containing the above-mentioned formaldehyde-trapping substance may be a cellulose resin, a vinyl resin,
It can be obtained by kneading a solvent-type or emulsion-type vehicle such as a polyester-based resin, an acrylic-based resin, or a nitrified cotton / polyamide-based resin, optionally adding one or more of the above-mentioned formaldehyde-trapping substances and an additive and kneading. it can. The amount of formaldehyde-trapping substance applied depends on the amount of formaldehyde-generating substances used in the production of decorative boards, but a good effect can be obtained if the amount is approximately 1.5 to 2.0 times the expected amount of formaldehyde generation. can get. Needless to say, the coating liquid may be colored by adding a pigment.

The shielding layer 5 has an adhesive property to the picture layer 2 and the formaldehyde trapping layer 4 and the formaldehyde trapping layer of isocyanate which is a curing agent of the two-component curable polyurethane resin used for the protective layer 1. For example, ethylene copolymer resins such as ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl acrylate copolymer, ethylene-vinyl acetate, etc. Is preferred. The shielding layer 5 is formed by coating the emulsion solution of the ethylene copolymer resin on the surface of the formaldehyde trapping layer 4 of the paper substrate 3 on which the formaldehyde trapping layer 4 is formed by a well-known roll coating method, gravure coating method, or the like. And can be formed
Further, it can be formed by coating the above-mentioned ethylene copolymer resin by a known T-die extrusion lamination method.
The primary purpose of the shielding layer 5 is to form a uniform ethylene copolymer resin layer, and the thickness of the shielding layer 5 is not limited.

Next, the pattern layer 2 can be formed, for example, by printing with a printing ink made of a resin that adheres to the ethylene copolymer resin used for the shielding layer 5. The printing ink is a vinyl resin, an acrylic resin, a nitrified cotton / polyamide resin, a modified polyolefin resin such as chlorinated polyethylene or chlorinated polypropylene,
It can be obtained by arbitrarily adding a pigment or an additive to a vehicle such as a urethane-based resin and kneading the mixture. The protective layer 1 is, of course, a two-component curable polyurethane resin, and is formed by a well-known roll coating method or gravure coating method.
It can be formed by applying a coating liquid of a liquid-curable polyurethane resin. The coating thickness is suitably 3 to 6 μm. Needless to say, the coating liquid may be colored by adding a pigment or the like as necessary.

FIG. 2 is a sectional view showing a layer structure of a decorative sheet according to a second embodiment of the present invention. The decorative sheet 10 includes a protective layer 1, a picture layer 2, a shielding layer 5, a formaldehyde trapping layer 4, and paper. Substrates 3 'are sequentially stacked. The paper base 3 'has the same configuration as that of the first embodiment except that the paper base 3' is composed of a laminate of a paper base 3, an adhesive layer 6, and a paper base 3. As the adhesive used for the adhesive layer 6, an emulsion-type adhesive such as ethylene-vinyl acetate, vinyl chloride-vinyl acetate, acryl, or rubber can be used. By laminating 3 and 3, the paper substrate 3 'can be formed.

FIG. 3 is a sectional view showing a layer structure of a decorative sheet according to a third embodiment of the present invention. The decorative sheet 10 includes a protective layer 1, a picture layer 2, a paper substrate 3 ", and a formaldehyde capturing layer 4.
Are sequentially stacked. The paper substrate 3 "is composed of a laminate of paper substrate 3 / adhesive layer 6 '/ paper substrate 3, and the adhesive layer 6' also serves as the shielding layer 5. The adhesive used for this is polyethylene. Suitable are hot-melt resins such as olefins such as polyethylene, polypropylene and the like, ionomers, ethylene copolymers such as ethylene-acrylic acid copolymers, ethylene-methyl acrylate copolymers and ethylene-methacrylic acid copolymers. Between the paper substrates 3 and 3
The paper substrate 3 ″ can be formed by coating by a die extrusion lamination method. In this case, the adhesive layer
6 'is suitably 13 to 50 µm. The protective layer 1, the picture layer 2, and the formaldehyde trapping layer 4 may be formed in the same manner as in the first embodiment, and the description thereof will be omitted. In order not to allow the permeation of formaldehyde, the formaldehyde remaining on the paper substrate 3 on the side of the adhesive layer 6 'on which the formaldehyde trapping layer 4 is formed can be reliably trapped, and the emission to the outside can be further reduced.

FIG. 4 is a sectional view showing the layer structure of a decorative sheet according to a fourth embodiment of the present invention. The decorative sheet 10 'includes a protective layer 1, a shielding layer 5, and a picture layer 2 containing a formaldehyde trapping substance. ', Paper substrates 3 are sequentially laminated. The printing ink for forming the picture layer 2 'containing the formaldehyde trapping substance includes nitrified cotton / alkyd, nitrified cotton / polyamide, cellulose, vinyl chloride, vinyl chloride / vinyl acetate, acrylic, and ester resins. It can be obtained by arbitrarily kneading the above-mentioned formaldehyde trapping substance, pigment and additive in a solvent type or emulsion type vehicle. Further, the shielding layer 5 and the protective layer 1 can be formed by the same method as described in the first embodiment, and the description is omitted.

FIG. 5 is a sectional view showing a layer structure of a decorative sheet according to a fifth embodiment of the present invention. The decorative sheet 10 'includes a protective layer 1, a shielding layer 5, and a picture layer 2 containing a formaldehyde trapping substance. ', Paper substrate 3' are sequentially laminated. In the present embodiment, a paper substrate 3 'composed of a laminate of the paper substrate 3 / adhesive layer 6 / paper substrate 3 used in the second embodiment is used instead of the paper substrate 3 of the fourth embodiment. Description is omitted.

FIG. 6 is a sectional view showing a layer structure of a sixth embodiment of the decorative sheet of the present invention. It can be formed by the same method as described in the first to fifth aspects, and the description is omitted.

The first to sixth embodiments of the decorative sheet of the present invention shown in FIGS. 1 to 6 are all composed of a two-component curable polyurethane resin used for a protective layer and an organic amino compound used for a formaldehyde capturing layer. A decorative layer is provided between the protective layer and the formaldehyde-trapping layer in order to prevent direct contact between the decorative sheet and the decorative sheet. In the first to sixth embodiments, the layer and the formaldehyde trapping layer are in direct or indirect contact with each other. To prevent this, the protective layer of the decorative sheet comes in contact with the protective layer in the form of a roll. The resin layer used for the above-described shielding layer may be formed on the opposite surface. In this case, it is preferable to use an emulsion solution of the resin used for the shielding layer. However, in the second embodiment shown in FIG. 2, the same effect as the shielding layer provided on the surface of the paper base 3 'opposite to the protective layer of the decorative sheet can be expected.

In the first to third and sixth embodiments of the present invention, the protective layer and the picture layer are separated by the formaldehyde trapping layer and the shielding layer. In this case, the picture layer is formed. It is also possible to use a two-component curable polyurethane resin as a binder for the printing ink to be used.

[0023]

The present invention will be described in more detail with reference to the following examples. Example 1 A well-known gravure printing method using a nitrified cotton-based coating liquid in which 10% of a clay supporting piperidine of a 6-membered saturated cyclic secondary amine which is a formaldehyde trapping substance was added to one surface of a thin paper having a basis weight of 30 g / m ² , To form a formaldehyde-trapping layer, and print and shield an emulsion solution of an ethylene-acrylic acid copolymer on the formaldehyde-trapping layer by a well-known gravure printing method so as to form a layer of 1 g / m ² when dry. A colored solid ink layer is formed on the shielding layer using an acrylic printing ink, and a wood-grained pattern layer is formed thereon with an acrylic ink. forming a protective layer such that the 5 g / m ² dry when a well-known gravure printing method using a coating liquid of the liquid curable polyurethane resin, the present invention It was obtained 粧 sheet A. Example 2 Thin paper having a basis weight of 30 g / m ² was extruded from low-density polyethylene by 15 μm to form a laminate of thin paper / low-density polyethylene / thin paper, and one side of the laminate was patterned with a nitrifying cotton-based ink. A layer is formed by a well-known gravure printing method, and a protective layer is formed on the entire surface of the picture layer by a gravure printing method using a coating liquid of a two-component curable polyurethane resin so as to be 5 g / m ² when dry. Then, a nitrified cotton-based coating liquid containing 10% of a clay supporting a piperidine of a 6-membered saturated cyclic secondary amine as a formaldehyde capturing substance is continuously added to the other surface of the laminate by well-known gravure printing. A decorative sheet B of the present invention was obtained by forming a formaldehyde-trapping layer by printing by a method. Comparative Example 1 A wood-grained pattern layer was formed on one surface of thin paper having a basis weight of 30 g / m ^{2 with} a nitrocellulose-based ink by a well-known gravure printing method, and a two-component curable polyurethane resin was formed on the entire surface of the pattern layer. 5g when dry by gravure printing method using coating liquid
/ M ^2, and 10% of clay carrying a piperidine of a 6-membered saturated cyclic secondary amine as a formaldehyde scavenger was continuously added to the other surface of the thin paper. A nitrifying cotton-based coating solution was printed by a well-known gravure printing method to obtain a decorative sheet C to be compared.

Each of the decorative sheets A, B, and C of the above Examples 1 and 2 and Comparative Example 1 was laminated on a single piece of rawan wood with a urea resin-based adhesive. Decorative boards were attached to each other using a system adhesive. These decorative panels were carried out in accordance with the formaldehyde quantitative test specified in Japanese Agricultural Standards, and the results are shown in Table 1.

[0025]

[Table 1] As is clear from Table 1, the decorative sheet of the present invention is effective as a decorative sheet having a function of capturing formaldehyde by providing a shielding layer so that the two-component curable polyurethane resin and the formaldehyde capturing layer are not in direct contact. It was confirmed that it was.

[0026]

As described above, the decorative sheet of the present invention is made of a material such as a resin used for the protective layer and the like, for example, a two-component curable polyurethane resin and a material such as a formaldehyde capturing substance used for the formaldehyde capturing layer. For example, in a decorative sheet having a formaldehyde capturing function having a configuration using an organic amino compound, by providing a shielding layer, the protective layer and the formaldehyde capturing layer are prevented from reacting with each other, and the decorative sheet has a formaldehyde capturing function. A decorative sheet having excellent surface friction and chemical properties can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a layer configuration of a first embodiment of a decorative sheet of the present invention.

FIG. 2 is a sectional view showing a layer configuration of a decorative sheet according to a second embodiment of the present invention.

FIG. 3 is a sectional view showing a layer configuration of a decorative sheet according to a third embodiment of the present invention.

FIG. 4 is a sectional view showing a layer structure of a decorative sheet according to a fourth embodiment of the present invention.

FIG. 5 is a cross-sectional view illustrating a layer configuration of a decorative sheet according to a fifth embodiment of the present invention.

FIG. 6 is a sectional view showing a layer structure of a decorative sheet according to a sixth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Protective layer 2, 2 'Picture layer 3, 3', 3 "Paper base 4 Formaldehyde trapping layer 5 Shielding layer 6, 6 'Adhesive layer 10, 10' Decorative sheet

Claims (2)

[Claims] 1. A laminate comprising a protective layer, a picture layer, a formaldehyde trapping layer, a shielding layer and a paper substrate, wherein the outermost surface layer of the laminate comprises the protective layer, and a laminate is formed between the protective layer and the formaldehyde trapping layer. A decorative sheet, wherein the shielding layer is formed. 2. A laminate comprising a protective layer, a picture layer, a paper substrate and a shielding layer, wherein the outermost surface layer of the laminate comprises the protective layer, and the picture layer contains a formaldehyde-trapping substance; A decorative sheet, wherein the shielding layer is formed between a protective layer and the picture layer.