JP4807269B2 - Raw material for foam wallpaper and foam wallpaper - Google Patents

Description

  The present invention relates to a foam fabric and a foam wallpaper.

  The raw material for foam wallpaper (material) and the foam wallpaper (product) have the following relationship. That is, the raw material for foam wallpaper is a material for producing foam wallpaper, and has a foaming agent-containing resin layer in an unfoamed state. The raw fabric is made into a foamed wallpaper (product) by foaming the foaming agent-containing resin layer to form a foamed resin layer and, if necessary, decorated or embossed.

  Conventionally, as foam wallpaper, a paper base (backing paper) in which a foam resin layer made of a vinyl chloride resin (vinyl chloride resin) is formed is known. However, in recent years, a so-called non-vinyl chloride resin wallpaper using, for example, a polyolefin-based resin without using a vinyl resin for the foamed resin layer in consideration of the environment has been proposed (Patent Documents 1 to 3, etc.).

  The foamed wallpaper is desired to have a high surface strength. As a method for increasing the surface strength, for example, a method using an ethylene-unsaturated carboxylic acid copolymer as a resin constituting the foamed resin layer is known. In this case, the ethylene-unsaturated carboxylic acid copolymer is included in the resin component of the foaming agent-containing resin layer of the original foam wallpaper, and the foaming resin layer is formed by foaming the foaming agent-containing resin layer. It is formed.

However, since the ethylene-unsaturated carboxylic acid copolymer contains carboxylic acid in the molecule, hydrogen bonding occurs between the molecules, resulting in heating at a higher temperature for a longer time than when using other ethylene copolymers. Otherwise, there is a problem that desired foaming characteristics (foaming ratio, surface condition, etc.) cannot be obtained. Thus, heating at a high temperature for a long time causes burning of the paper-based substrate and also causes discoloration of the resin layer, so there is room for improvement.
Japanese Patent Laid-Open No. 6-47875 JP 2000-255011 A JP 2001-347611 A

  An object of the present invention is to provide a raw material for foamed wallpaper that can exhibit good foaming characteristics without causing burning of a paper-based substrate and is suitable for producing a foamed wallpaper having high surface strength.

  As a result of intensive studies, the present inventors have found that the above object can be achieved when a specific resin component is contained in the foaming agent-containing resin layer, and have completed the present invention.

  That is, the present invention relates to the following foam fabric and foam wallpaper.

1. A raw material for foam wallpaper having at least a paper-based substrate and a foaming agent-containing resin layer,
(1) The foaming agent-containing resin layer contains an ethylene-unsaturated carboxylic acid copolymer in the resin component,
(2) The unsaturated carboxylic acid content in the resin component is 2 to 10% by weight.
An original fabric for foam wallpaper.

  2. Item 2. The raw material for foamed wallpaper according to Item 1, wherein the resin component further contains an ethylene-vinyl acetate copolymer.

  3. Item 3. The raw material for foamed wallpaper according to Item 1 or 2, wherein the unsaturated carboxylic acid is acrylic acid or methacrylic acid.

  4). The non-foamed resin layer is further provided, and the non-foamed resin layer is formed so as to be a foaming agent-containing resin layer and a non-foamed resin layer in order from the paper-based substrate. Raw material for foam wallpaper.

  5. Item 5. The raw material for foamed wallpaper according to Item 4, wherein a non-foamed resin layer is further formed between the paper-based substrate and the foaming agent-containing resin layer.

  6). A foamed wallpaper obtained by foaming the foaming agent-containing resin layer of the raw fabric for foamed wallpaper according to any one of Items 1 to 5.

7). Item 7. The foamed wallpaper according to Item 6, wherein embossing is performed on the outermost surface layer.

Hereinafter, the raw fabric for foamed wallpaper and the foamed wallpaper of the present invention will be described.

The raw material for foamed wallpaper of the present invention has at least a paper-based substrate and a foaming agent-containing resin layer,
(1) The foaming agent-containing resin layer contains an ethylene-unsaturated carboxylic acid copolymer in the resin component,
(2) The unsaturated carboxylic acid content in the resin component is 2 to 10% by weight.
It is characterized by that.

  The raw material for foamed wallpaper of the present invention having the above characteristics has an unsaturated carboxylic acid content in the resin component of the foaming agent-containing resin layer of 2 to 10% by weight. The desired foaming characteristics can be expressed while preventing deterioration (discoloration), and the surface condition is good (the foamed cells are uniform and the foamed surface is smooth). Moreover, the foamed wallpaper obtained from the raw material for foamed wallpaper has good surface strength.

(Paper base material)
The material of the paper base is not particularly limited as long as it has mechanical strength, heat resistance and the like suitable as a wallpaper base, and a fibrous sheet can be generally used.

  Specifically, among fiber sheets, flame retardant paper (pulp-based sheets treated with flame retardants such as guanidine sulfamate and guanidine phosphate); inorganic additives such as aluminum hydroxide and magnesium hydroxide Inorganic paper including; fine paper; thin paper and the like.

The basis weight of the paper quality substrate is not limited, but preferably about 50 to 300 g / ^{m 2,} about 50 to 80 g / ^{m 2} is more preferable.

(Non-foamed resin layer B)
The non-foamed resin layer B may be formed between the paper-based substrate and the foaming agent-containing resin layer in the foamed wallpaper raw material of the present invention. In particular, when the non-foamed resin layer B is formed as an adhesive layer, excellent adhesion between the resin layer and the paper-based substrate can be obtained. As the non-foamed resin layer B, for example, ethylene-vinyl acetate copolymer (EVA) or the like can be suitably used.

  The non-foamed resin layer B may be substantially only a resin component, but may contain a known additive as necessary. The content of the resin component in the non-foamed resin layer B is preferably set in the range of 70 to 100% by weight.

  The thickness of the non-foamed resin layer B is not limited, but is preferably about 5 to 50 μm.

(Foaming agent-containing resin layer)
The foaming agent-containing resin layer contains a resin component and a pyrolytic foaming agent, and may further contain additives such as an inorganic filler, a pigment, and a cell conditioner as necessary.

  The resin component contains an ethylene-unsaturated carboxylic acid copolymer as an essential component, and the unsaturated carboxylic acid content in the resin component is 2 to 10% by weight.

Examples of the ethylene-unsaturated carboxylic acid copolymer include ethylene-methacrylic acid (CH ₂ ═C (CH ₃ ) COOH) copolymer (EMAA) and ethylene-acrylic acid (CH ₂ ═CHCOOH) copolymer. (EAA) etc. are mentioned. The unsaturated carboxylic acid content in the resin component may be 2 to 10% by weight.

  The method for adjusting the content of the unsaturated carboxylic acid is not limited. The method for adjusting the copolymerization ratio of the unsaturated carboxylic acid, by further copolymerizing an unsaturated ester or the like with the ethylene-unsaturated carboxylic acid copolymer. Examples thereof include a method for adjusting the unsaturated carboxylic acid content and a method for further mixing a resin component not containing the unsaturated carboxylic acid. For example, EVA is suitable as the resin component not containing the unsaturated carboxylic acid.

  The pyrolytic foaming agent is not limited, and examples thereof include azo series such as azodicarbonamide (ADCA) and azobisformamide; and birazide series such as oxybenzenesulfonyl hydrazide (OBSH) and paratoluenesulfonyl hydrazide.

  The content of the thermally decomposable foaming agent can be appropriately set according to the type of foaming agent, the foaming ratio (the thickness of the foamed resin layer with respect to the foaming agent-containing resin layer), and the like. The expansion ratio is preferably 1.5 times or more, and more preferably about 3 to 7 times. From this viewpoint, the content of the pyrolytic foaming agent is preferably about 1 to 20 parts by weight with respect to 100 parts by weight of the resin component.

  Examples of the inorganic filler include calcium carbonate, aluminum hydroxide, magnesium hydroxide, antimony trioxide, zinc borate, and a molybdenum compound. By including an inorganic filler, an effect of suppressing see-through, an effect of improving surface characteristics, and the like are obtained. About 0-100 weight part is preferable with respect to 100 weight part of resin components, and, as for content of an inorganic filler, about 20-70 weight part is more preferable.

  As for pigments, for example, titanium oxide, zinc white, carbon black, black iron oxide, yellow iron oxide, yellow lead, molybdate orange, cadmium yellow, nickel titanium yellow, chrome titanium yellow, iron oxide (valve), cadmium red Inorganic pigments such as ultramarine, bituminous, cobalt blue, chromium oxide, cobalt green, aluminum powder, bronze powder, titanium mica, zinc sulfide; for example, aniline black, perylene black, azo (azo lake, insoluble azo, condensed azo), Polycyclic (isoindolinone, isoindoline, quinophthalone, perinone, flavantron, anthrapyrimidine, anthraquinone, quinacridone, perylene, diketopyrrolopyrrole, dibromoanthanthrone, dioxazine, thioindigo, phthalocyanine, indanthro , And organic pigments halogenated phthalocyanine), or the like. The content of the pigment is preferably about 10 to 50 parts by weight and more preferably about 15 to 30 parts by weight with respect to 100 parts by weight of the resin component.

  As the cell adjusting agent, for example, a metal soap such as zinc stearate can be used. The content of the cell regulator is preferably about 0.3 to 10 parts by weight, and more preferably about 0.5 to 5 parts by weight with respect to 100 parts by weight of the resin component.

  Although the thickness of a foaming agent containing resin layer is not limited, About 50-200 micrometers is preferable.

(Non-foamed resin layer A)
The raw material for foamed wallpaper of the present invention can also be provided with the non-foamed resin layer A on the foaming agent-containing resin layer (on the side opposite to the paper-based substrate). The non-foamed resin layer A serves as, for example, a surface protective layer for the foamed wallpaper that is the final product.

The resin component contained in the non-foamed resin layer A is not limited, but a polymer obtained using at least one of acrylic acid (CH ₂ ═CHCOOH) and methacrylic acid (CH ₂ ═C (CH ₃ ) COOH) as a monomer It is preferable to contain.

  As the resin component, for example, a copolymer obtained by combining at least one of acrylic acid and methacrylic acid with a monomer and ethylene can be suitably used as the resin component. More specifically, at least one of the above EAA, EMAA, and ionomer resin is desirable. When such a resin component is used, a strong layer caused by hydrogen bonds in the resin can be formed, and thus excellent scratch resistance, abrasion resistance, and the like are easily obtained.

  The content of acrylic acid (AA) or methacrylic acid (MAA) in the copolymer is preferably about 4 to 20% by weight.

  The non-foamed resin layer A may be substantially only a resin component, but may contain a known additive as required. The content of the resin component in the non-foamed resin layer A is preferably set in the range of 70 to 100% by weight.

  The thickness of the non-foamed resin layer A is not limited, but is preferably about 5 to 50 μm.

  Although the melt flow rate value of the resin component depends on the type of the resin component used, etc., it is usually preferably 10 to 60 g / 10 min. When the MFR value of the non-foamed resin layer is high, the foamed gas on the surface of the foamed resin layer enters the non-foamed resin layer, and therefore it is particularly preferably in the range of 10 to 35 g / 10 minutes. By using a material having such a numerical range, more excellent scratch resistance, wear resistance and the like can be obtained.

(Manufacturing method of raw material for foam wallpaper)
The method for producing the foam fabric for the wallpaper is not limited. After the resin composition for forming each layer is formed by simultaneous melt extrusion, a resin layer (laminate) is formed, and then the resin layer and the paper substrate are thermally laminated. The method is preferred.

  For simultaneous melt extrusion, for example, co-extrusion by a T-die extruder is suitable. For example, a multi-manifold T-die extruder capable of co-extrusion of a plurality of layers can be suitably used for simultaneous melt extrusion of resin layers. In this case, the resin composition for forming each resin layer may be filled in separate cylinders, and the cylinders may be heated to melt and extrude the resin layers simultaneously.

  Although the heating temperature of each cylinder can be appropriately set according to the type of the resin composition, generally the cylinder temperature is preferably about 100 to 140 ° C, more preferably about 110 to 130 ° C. The die temperature is preferably about 110 to 130 ° C.

  In thermal lamination, a resin sheet may be laminated on a heated paper base material and laminated. The heating temperature of the paper-based substrate is not limited, but is preferably about 80 to 120 ° C, more preferably about 90 to 100 ° C.

The raw material for foamed wallpaper can be made into a foamed wallpaper by further foaming a foaming agent-containing resin layer into a foamed resin layer. Specifically, the foamed resin layer is formed by thermally decomposing and foaming the foaming agent by heating the raw material for foamed wallpaper. A gear oven or the like can be used for heating.

  Although heating conditions are not limited, about 200-235 degreeC is preferable and about 220-230 degreeC is more preferable. The heating time is not limited, but is preferably about 20 to 60 seconds, more preferably about 30 to 40 seconds. Under such heating conditions, desired foaming characteristics can be obtained without burning the paper-based substrate and changing the color of the resin layer. The expansion ratio is 1.5 times or more, preferably about 3 to 7 times, and the surface state is good (the foamed cells are uniform and the foamed surface is smooth).

  Further, the resin layer may be irradiated with an electron beam before the heat treatment. For example, the electron beam may be irradiated from the foamed resin layer A side. The resin component (especially EVA) can be cross-linked by electron beam irradiation to control the surface strength, foaming degree, etc. of the foam wallpaper. The energy of the electron beam is preferably about 150 to 250 kV. The irradiation amount is preferably about 10 to 100 kGy. A known electron beam irradiation apparatus can be used as the electron beam source.

  When performing electron beam irradiation, you may contain a crosslinking adjuvant in the said resin composition. Any crosslinking aid may be used as long as it promotes crosslinking by electron beam irradiation. Examples thereof include polyfunctional monomers such as neopentyl glycol dimethacrylate and trimethylolpropane trimethacrylate, oligomers, and the like. The crosslinking aid is preferably about 0 to 10 parts by weight and more preferably about 1 to 4 parts by weight with respect to 100 parts by weight of the resin component.

  The foamed wallpaper may have a pattern layer (texture pattern or the like) on the outermost surface layer.

  Examples of the design pattern include a wood grain pattern, a stone pattern, a grain pattern, a tiled pattern, a brickwork pattern, a cloth pattern, a leather pattern, a geometric figure, a character, a symbol, and an abstract pattern. The pattern can be selected according to the type of foam wallpaper.

  The pattern pattern layer is formed by printing a pattern pattern on the front surface of the non-foamed resin layer A. The pattern layer is preferably formed before the heat treatment. Examples of printing methods include gravure printing, flexographic printing, silk screen printing, and offset printing. As the printing ink, a printing ink containing a colorant, a vehicle, and a solvent can be used. These inks may be known or commercially available.

  The colorant may be the same as the pigment that can be used in the foaming agent-containing resin layer, for example.

  The resin component contained in printing ink can be set according to the kind of base material sheet. For example, acrylic resin, styrene resin, polyester resin, urethane resin, chlorinated polyolefin resin, vinyl chloride-vinyl acetate copolymer resin, polyvinyl butyral resin, alkyd resin, petroleum resin, ketone resin, epoxy Resin, melamine resin, fluorine resin, silicone resin, fiber derivative, rubber resin and the like.

  Examples of the solvent (or dispersion medium) contained in the printing ink include petroleum-based organic solvents such as hexane, heptane, octane, toluene, xylene, ethylbenzene, cyclohexane, and methylcyclohexane; ethyl acetate, butyl acetate, and 2-methoxyacetate. Ester-based organic solvents such as ethyl and 2-ethoxyethyl acetate; alcohol-based organic solvents such as methyl alcohol, ethyl alcohol, normal propyl alcohol, isopropyl alcohol, isobutyl alcohol, ethylene glycol, propylene glycol; acetone, methyl ethyl ketone, methyl isobutyl ketone Ketone organic solvents such as cyclohexanone; ether organic solvents such as diethyl ether, dioxane and tetrahydrofuran; dichloromethane, carbon tetrachloride, trichloroethylene, Chlorinated organic solvents such as tiger chloroethylene; and water.

  The thickness of the design pattern layer is different from the type of design pattern, but is generally preferably about 0.1 to 10 μm.

  The foamed wallpaper may be embossed from the top surface layer. Embossing may be performed according to a conventional method. For example, the embossed pattern can be formed by pressing the embossed plate after heat softening the front surface of the non-foamed resin layer A of the foam wallpaper (after forming the foamed resin layer). Examples of the embossed pattern include a wood grain plate conduit groove, a stone plate surface unevenness, a cloth surface texture, a satin texture, a grain texture, a hairline, and a multiline groove.

  Since the unsaturated carboxylic acid content in the resin component of the foaming agent-containing resin layer is 2 to 10% by weight in the raw material for foamed wallpaper of the present invention, the paper substrate and the resin layer are altered (discolored) during the foaming process. ), The desired foaming characteristics can be expressed, and the surface state is good (the foamed cells are uniform and the foamed surface is smooth). Moreover, the foamed wallpaper obtained from the raw material for foamed wallpaper has good surface strength.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited to the examples.

Example 1
Using a three-type three-layer multi-manifold T-die extruder, films were formed in the order of i) non-foamed resin layer / ii) foaming agent-containing resin layer / iii) non-foamed resin layer in the order of 10 μm / 100 μm / 10 μm. The extrusion conditions were as follows: the i) layer resin had a cylinder temperature of 140 ° C., the ii) layer resin had a cylinder temperature of 120 ° C., and the iii) layer resin had a cylinder temperature of 100 ° C. The die temperatures were all 120 ° C.

  Next, a backing paper “NI-65A, made by Nippon Paper Industries” with a surface temperature of 90 ° C. was laminated on the surface of the layer iii). Thereby, the raw material for foam wallpaper was produced.

Next, an electron beam (200 KV, 30 kGy) was irradiated from above the i) layer of the foam wallpaper base material, and the i) layer and the ii) layer were subjected to resin crosslinking, and then the corona discharge treatment was performed on the i) layer. . Furthermore, 2 g / m ² of the EVA emulsion was applied as a primer treatment by a gravure printing machine, and a texture pattern was printed thereon using water-based ink “Hydric, manufactured by Dainichi Seika Kogyo” as a pattern print.

  Next, heating is performed in a gear oven (heating conditions are 1) “220 ° C. × 35 seconds” and 2) “240 ° C. × 35 seconds”), and the foaming agent contained in the foaming agent-containing resin layer is foamed. I let you. Further, a foamed wallpaper was prepared by embossing the embossed pattern of the fabric pattern on the foam.

  Each layer was formed using the following components.

  The non-foamed resin layer i) was formed from an ethylene-methacrylic acid copolymer “Nucleel N1560, manufactured by Mitsui DuPont Polychemical”.

  The foamed resin layer ii) is composed of 100 parts by weight of ethylene-methacrylic acid copolymer “Nucleel N1035 (MAA content = 10% by weight), Mitsui DuPont Polychemical”, calcium carbonate “Whiteon H, Toyo Fine Chemical” 30 Parts by weight, titanium dioxide “R-108, made by DuPont” 25 parts by weight, foaming agent “Vinhole AC # 3, made by Eiwa Chemical Industries” 4 parts by weight, stabilizer “ADK STAB OF-102, made by Asahi Denka Kogyo” 5 parts by weight The resin composition containing 1 part by weight of a crosslinking aid “OPSTA JUA-702: manufactured by JSR” (the unsaturated carboxylic acid content in the resin component is 10% by weight).

  The non-foamed resin layer iii) was formed by EVA “Evaflex EV150 (VA content = 33 wt%), manufactured by Mitsui DuPont Polychemical”.

Example 2
ii) The resin component of the layer is 65 parts by weight of EMAA “Nucrel N1560 (MAA content = 15% by weight), made by Mitsui DuPont Polychemical” and 35 parts by weight of EVA “Evaflex V406, made by Mitsui DuPont Polychemical” A foamed wallpaper was prepared in the same manner as in Example 1 except that the mixture (the unsaturated carboxylic acid content in the resin component was 9.8% by weight) was used.

Example 3
ii) Implementation was performed except that the resin component of the layer was EMAA “Nucleel N035C (MAA content = 10 wt%), made by Mitsui DuPont Polychemical” (the unsaturated carboxylic acid content in the resin component was 10 wt%) A foamed wallpaper was prepared in the same manner as in Example 1.

Example 4
ii) Implementation was performed except that the resin component of the layer was EMAA “Nucrel N0200H (MAA content = 2 wt%), made by Mitsui DuPont Polychemical” (the unsaturated carboxylic acid content in the resin component was 2 wt%) A foamed wallpaper was prepared in the same manner as in Example 1.

Example 5
ii) Other than EAA “Lexpearl AS211S (acrylic acid content = 8.5% by weight), made by Nippon Polyethylene” (unsaturated carboxylic acid content in the resin component is 8.5% by weight) Produced a foamed wallpaper in the same manner as in Example 1.

Comparative Example 1
ii) Implementation was performed except that the resin component of the layer was EMAA “Nucleel N1110H (MAA content = 11% by weight), made by Mitsui DuPont Polychemical” (the unsaturated carboxylic acid content in the resin component was 11% by weight) A foamed wallpaper was prepared in the same manner as in Example 1.

Comparative Example 2
ii) The resin component of the layer is 10 parts by weight of EMAA “Nucleel N1035 (MAA content = 10% by weight), made by Mitsui DuPont Polychemical” and 90 parts by weight of EVA “Evaflex V406, made by Mitsui DuPont Polychemical”. A foam wallpaper was prepared in the same manner as in Example 1 except that the mixture was 1% by weight (unsaturated carboxylic acid content in the resin component).

Test Examples 1-3
The foamed wallpaper produced in Examples and Comparative Examples was evaluated for 1) foam volume, 2) backing paper burn, and 3) surface strength. The results are shown in Table 1.

<< Test Example 1 >>
The foam volume was evaluated by measuring the expansion ratio. The evaluation criteria were as follows.
○: The expansion ratio is 3 times or more and the surface state is good (the foamed cells are uniform and the foamed surface is smooth).
Δ: The expansion ratio is 3 times or more, but the surface condition is poor (the foamed cells are large and uneven, and the foamed surface has a concave).
X: Foaming ratio is less than 3 times

<< Test Example 2 >>
Burns were evaluated from the color difference of the backing paper before and after the foaming process. The color difference “ΔE” was calculated according to JIS Z8730.7 by measuring the values of L ^* , a ^* and b ^* according to JIS Z8730.6.2 using a photoelectric colorimeter. The evaluation criteria were as follows.
○: ΔE is less than 3 ×: ΔE is 3 or more

<< Test Example 3 >>
The surface strength was evaluated in accordance with the “Surface-Enhanced Product Performance Test” established by the Japan Vinyl Industry Association Construction Committee. The evaluation criteria were as follows.
○: Grade 5 ×: Grade 4 or lower

Claims (7)

A raw material for foam wallpaper having at least a paper-based substrate and a foaming agent-containing resin layer,
(1) The foaming agent-containing resin layer contains an ethylene-unsaturated carboxylic acid copolymer in the resin component,
(2) The unsaturated carboxylic acid content in the resin component is 2 to 10% by weight.
An original fabric for foam wallpaper.   The raw material for foamed wallpaper according to claim 1, further comprising an ethylene-vinyl acetate copolymer in the resin component.   The raw fabric for foamed wallpaper according to claim 1 or 2, wherein the unsaturated carboxylic acid is acrylic acid or methacrylic acid.   It further has a non-foaming resin layer, and the non-foaming resin layer is formed so that it may become a foaming agent content resin layer and a non-foaming resin layer in order from a paper-like base material. Raw material for foam wallpaper.   The raw material for foamed wallpaper according to claim 4, wherein a non-foamed resin layer is further formed between the paper-based substrate and the foaming agent-containing resin layer.   A foam wallpaper obtained by foaming the foaming agent-containing resin layer of the raw fabric for foam wallpaper according to any one of claims 1 to 5.   The foamed wallpaper according to claim 6, wherein embossing is performed on the outermost surface layer.