JPH1076587A - Foamed sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the stain-resistance and chemical-resistance by causing a portion printed with foam-suppressing ink to be printed so as to coincide with a recessed portion of a foamed resin layer and curing an ultraviolet-ray curable resin after foaming aqueous paint is foamed. SOLUTION: An inorganic paper is used for a base material 1, and a formulated foaming aqueous paint is coated on this paper and dried. Following this, optional patterns are gravure printed with a foam-suppressing ink 3 and a normal ink 4, respectively and then dried so as to form a printed ink layer 5. Following this, an ultraviolet-ray curable resin is coated by gravure printing and dried. Next, the foaming aqueous paint is foamed, the portion printed with the foam-suppressing ink is restrained from foaming, the portion not printed with the foam-suppressing ink is allowed to be foamed to form a foamed resin layer 2 to obtain a recessed and raised pattern that is tuned to the pattern by the foam-suppressing ink. Following this, ultraviolet rays are irradiated onto the foamed resin surface to cure the ultraviolet-ray curable resin to form an ultraviolet-ray curable resin layer 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foamed sheet used for interior materials of buildings, which is provided with an uneven pattern on the surface, and which is excellent in quality such as stain resistance and surface strength.

[0002]

2. Description of the Related Art A method for producing a foamed sheet having an irregular pattern on the surface used as an interior material such as a wall material or a floor material of a building includes the following steps. , A foaming resin paste is applied and dried to form a foaming resin layer, a pattern is printed thereon with a printing ink, a heat treatment is applied to foam the foaming resin layer, and a foaming resin layer is formed. By a mechanical embossing method in which an embossing machine is used to impart a concavo-convex pattern. There is known, for example, a method using a chemical embossing method in which an uneven pattern is imparted in synchronism with a pattern by foaming under a portion where the foaming suppressing ink is not printed, in which the ink is suppressed. However, the foaming resin paste is mainly composed of a vinyl chloride resin and a plasticizer, and the foamed resin layer is liable to adhere to dust and tobacco tar by bleeding of the plasticizer onto the foam sheet surface over time. There was a problem. Also, when incinerating this foam sheet, the generation of a large amount of black smoke due to the plasticizer is a problem. On the other hand, recently, a foam sheet using a water-based resin paint such as an aqueous emulsion is being developed, and since the water-based resin paint does not use a plasticizer, the foam sheet is not stained by bleed.
In addition, when incinerating the foam sheet, the problem of generating a large amount of black smoke has been eliminated.

[0003]

However, the water-based resin foam sheet has excellent elasticity such as a vinyl chloride foam sheet.
It lacks toughness and is inferior in surface strength such as abrasion. In particular, a foamed sheet produced by a chemical embossing method using a foam-suppressing ink has a problem that the film strength is further weakened because the foamed sheet has a convex portion on the surface and is caught by rubbing. The present invention has been made in view of such problems, and the subject thereof is to form an uneven pattern by a chemical embossing method using an aqueous resin, and to form a surface strength, stain resistance, And a foam sheet excellent in chemical resistance and the like.

[0004]

In order to achieve the above object, according to the present invention, in the first aspect, a base material and a surface provided on one surface of the base material having a concave portion and a convex portion formed by foaming. A foamed resin layer composed of a patterned water-based paint for foaming, a printing ink layer having at least a portion printed with the foaming suppressing ink on the foamed resin layer, and cured by ultraviolet light provided on the printing ink layer A foamed sheet having a laminated structure composed of an ultraviolet curable resin layer made of an ultraviolet curable resin, wherein a portion printed with the foam suppressing ink is printed in accordance with a concave portion of the foam resin layer, and The UV-curable resin is a foamed sheet, wherein the foaming aqueous paint is cured after foaming to form an UV-curable resin layer.

In the method for producing a foamed sheet according to the present invention, a water-based foaming paint is applied to one surface of a substrate and dried to form a printing ink layer having at least a portion printed with a foam-suppressing ink on the water-based foaming paint. By applying an ultraviolet curing resin on the printing ink layer and then heating and foaming, the foaming aqueous resin under the printed portion of the foaming suppression ink is suppressed from foaming and becomes a recess, and the foaming suppression ink is The foamed aqueous resin under the unprinted portion is foamed to form a foamed resin layer provided with a concavo-convex pattern forming a convex portion, and finally, the ultraviolet curable resin is cured.

[0006] As described above, by applying the ultraviolet-curing resin and heating and foaming the foaming aqueous resin before curing the ultraviolet-curing resin, the ultraviolet-curing resin on the foamed portion of the foaming aqueous resin is heated. Can be foamed while being stretched. As a result, while having an uneven pattern,
It is possible to obtain a foamed sheet utilizing the excellent surface strength, stain resistance and the like of the ultraviolet curable resin.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The base material of the present invention is paper or the like, and among the papers, pulp paper-based flame-retardant paper impregnated with a water-soluble flame retardant such as guanazine sulfanilate and guanazine phosphate, calcium carbonate, aluminum hydroxide, water Inorganic paper obtained by mixing pulp with an inorganic agent such as magnesium oxide is preferable. Other than paper, a metal sheet such as a woven fabric, a nonwoven fabric, a plastic film, and a metal foil can be used, but the substrate is not particularly limited.

[0008] The aqueous foaming paint used in the foamed resin layer of the present invention comprises an aqueous resin, a foaming agent, a foaming accelerator, a filler and the like.

Examples of the aqueous resin include acrylic resins, aqueous urethane resins, polyolefin resins, vinyl chlorides, vinylidene chlorides, SBRs, vinyl acetates, ethylene vinyl acetate copolymers, silicones, polyurethanes and polybutenes. It is an aqueous emulsion or a water-soluble resin, and at least one or a mixture of two or more of these resins can be used.

Examples of the foaming agent include azo compounds such as azodicarbonamide (ADCA), azobisformamide (ABFA), and barium azodicarboxylate;
Dinitrosopentamethylenetetramine (DPT);
P'-oxybisbenzenesulfonyl hydrazide (O
Thermal decomposition type chemical blowing agents such as nitroso compounds such as BSH) can be used. The amount of the foaming agent to be added is as follows.
It is preferable to add 1 to 8 parts by weight, more preferably 2 to 6 parts by weight, per 100 parts by weight. If the amount is less than 2 parts, the expansion ratio is low, and the design properties of the foam sheet such as the suppression effect are inferior. If the amount is more than 8 parts by weight, the foamed cells are extremely rough, and the surface strength of the sheet is weak.

The foaming accelerator (foaming catalyst compound) is sometimes used to lower the decomposition temperature of the thermal decomposition type chemical foaming agent.
Fatty acid salts of Zn, Pd, Cd or their metal oxides are effective. For example, dibasic lead phosphite, dibasic lead stearate, a lead compound such as dibasic lead phthalite, zinc oxide, zinc laurate, zinc stearate, zinc carbonate, zinc salts such as zinc octoate, and Octoate cadmium and the like. The addition amount of the foaming accelerator is preferably 1 to 6 parts by weight.

As the filler, generally used inorganic agents such as calcium carbonate, aluminum hydroxide and magnesium hydroxide can be used, and among them, aluminum hydroxide having self-digestibility is preferable. The inorganic filler to be used preferably has an average particle size of 1 to 10 μm, more preferably 2 to 5 μm. If the particle size is larger than 10 μm, the surface of the applied water-based foaming foam becomes rough, and the printability deteriorates. When the particle size is less than 1 μm, agglomeration tends to occur in the water-based coating composition for foaming, and the cost is disadvantageous. The amount of the inorganic filler to be added is preferably 30 to 150 parts by weight, more preferably 50 to 100 parts by weight based on 100 parts by weight of the aqueous resin solids. If the addition amount is more than 150 parts by weight, the sheet strength becomes poor and 3
If the amount is less than 0 parts by weight, the flame-retardant effect cannot be obtained so much.

The water-based foam coating composition of the present invention may contain, as additives, a titanium pigment, a dispersant, an antifoaming agent, a wetting agent, an anti-blocking agent and a thickener.

As a method of mixing the aqueous paint for foaming, a Henschel mixer, a dissolver, a homomixer or the like is used.

As a coater for applying the foaming water-based paint to the substrate, a knife coater, a nozzle coater, a gravure coater, a rotary screen coater, a reverse coater, a comma coater and the like can be used.
The applied film can be dried by hot air drying or infrared irradiation alone or in combination.

The printing ink layer has a portion printed with the foaming suppressing ink, but may have a portion printed with a general printing ink, if necessary. The part printed with the foam-suppressing ink and the part printed with the general printing ink may be printed separately, or the part printed with the foam-suppressing ink may overlap the part printed with the general printing ink. .

As the foam-suppressing ink, any foam-suppressing ink used in the chemical embossing method of a polyvinyl chloride foam sheet can be used. Particularly, as the inhibitor, tolyltriazole, benzotriazole, aminotriazole, and trimellitic acid are preferable. Since the inhibitory effect of the inhibitor is proportional to the inhibitor concentration in the printing ink, it is usually 5%.
~ 75% is preferred.

As a printing method of the foaming suppressing ink on the foamed resin layer, a usual printing method such as a gravure printing method or a rotary screen printing method can be used.

As the general printing ink, a usual oil-based or water-based ink can be used. A printing method similar to the foaming suppression ink can be used.

The ultraviolet-curable resin layer is obtained by curing an ultraviolet-curable paint. The resin of the ultraviolet-curable paint may be a polyfunctional resin such as polyester acrylate, epoxy acrylate, polyether acrylate, urethane acrylate, and silicon acrylate. Acrylate polymers can be used. Further, blending with an acrylic aqueous emulsion resin is also possible.

The coater for applying the UV-curable paint is similar to the coater for applying the foaming aqueous paint to the substrate. The coating amount is 1 g / m ^{2 to} 20 g depending on the desired physical properties.
/ M ² is preferable, and if it is less than 1 g / m ² , physical properties such as chemical resistance cannot be sufficiently obtained, and if it is more than 20 g / m ² , it is disadvantageous in cost.

When the ultraviolet-curable resin layer of the present invention is made of a clear resin, the obtained foamed sheet becomes glossy and glossy, but titanium, calcium carbonate, aluminum hydroxide, When a matting agent such as magnesium hydroxide is added, a matte feeling can be obtained.

The method for drying the ultraviolet curable resin layer of the present invention can be used in the same manner as the above method. The dried sheet is further passed through a high-temperature foaming furnace, and a portion of the foamable resin layer on which the foaming suppression ink is not printed is heated and foamed to a desired foaming ratio. To cure.

As a method for curing the ultraviolet curable resin layer 5 of the present invention and a curing apparatus, known methods can be used. For example, Japanese Patent Application Laid-Open No. Sho 60-235793,
It is possible to use the curing method and the curing device described in JP-A-158451.

[0025]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
<Example 1> Basal weight 100 g / m as substrate 1^TwoMinerals
Using the paper, on the inorganic paper, the starting material shown in the formulation of Table 1 was used.
Aqueous paint for foam, with a comma coater, about 200g application amount
/ M ^TwoCoated and dried at about 90 ° C. for 3 minutes.
Then, using the foam suppressing ink 3 and the general ink 4 shown in Table 2,
And print with an arbitrary pattern using a gravure plate.
After drying for 1 minute, the printing ink layer 5 was provided. Then,
3g / m of UV curing resin shown in Table 3 in via plate^TwoKo
And dried at about 70 ° C. for 1 minute. Next,
Foamed water paint is foamed in a foaming furnace at about 180 ° C for 1 minute.
Foaming is suppressed in the area printed with the foaming suppression ink.
The part not printed with the foam control ink was foamed.
The foamed resin layer 2 is formed and is synchronized with the pattern of the foam-suppressing ink.
An uneven pattern was obtained. Next, the foam resin of the foam sheet
300mJ / cm on the surface^TwoUV curing by UV irradiation
The UV curing resin layer 6 was formed by curing the resin for use. Done
The raised foam sheet is resistant to contamination, chemicals and surface hardness.
It was excellent.

[0026]

[Table 1]

[0027]

[Table 2]

[0028]

[Table 3]

<Example 2> The substrate 1 had a basis weight of 100 g /
m^TwoThe inorganic paper of Table 1 was used on the inorganic paper.
Apply the water-based paint for foaming indicated with a comma coater.
About 200g / m ^TwoCoating, about 90 ° C for 3 minutes
While drying. Subsequently, the foam suppressing ink 3 shown in Table 2 and the general ink were used.
Use key 4 to print gravure plate with any pattern
After drying at about 70 ° C. for 1 minute, the printing ink layer 5 was provided. Continued
And the UV curable resin shown in Table 4 was
g / m^TwoCoat and dry at about 70 ° C for 1 minute
Was. Next, a foaming water-based paint is applied to a foaming furnace at about 180 ° C. for 1 minute.
Foamed, and the part printed with foaming suppression ink foams
Is suppressed, and parts not printed with the foaming suppression ink
The foamed foamed resin layer 2 is formed, and the pattern of the foaming suppression ink is formed.
A concavo-convex pattern synchronized with the above was obtained. Then, of the foam sheet
300mJ / cm on foam resin surface^TwoIrradiates the ultraviolet rays of purple
Curing the outside line curing resin to form an ultraviolet curing resin layer 6
Was. The resulting foam sheet is resistant to contamination, chemicals and
And excellent surface hardness.

[0030]

[Table 4]

<Comparative Example 1> The substrate 1 had a basis weight of 100 g /
m^TwoThe inorganic paper of Table 1 was used on the inorganic paper.
Apply the water-based paint for foaming indicated with a comma coater.
About 200g / m ^TwoCoating, about 90 ° C for 3 minutes
It was dry. Subsequently, the foam suppressing ink 3 and the general ink shown in Table 2
4, each was printed with an arbitrary pattern on the gravure plate
After that, it is dried at about 70 ° C. for 1 minute to provide a printing ink layer 5.
Was. Next, a foaming water-based paint is applied to a foaming furnace at about 180 ° C. for 1 minute.
Foamed, and the part printed with foaming suppression ink foams
Is suppressed, and parts not printed with the foaming suppression ink
The foamed foamed resin layer 2 is formed, and the pattern of the foaming suppression ink is formed.
A concavo-convex pattern synchronized with the above was obtained. UV curing resin layer
Because it did not, the stain resistance of the finished foam sheet,
Chemical resistance and surface hardness were very weak.

Table 5 shows the results of comparing the physical properties of the above Examples and Comparative Examples.

[0033]

[Table 5]

[0034]

As described above, the present invention has the following effects. (1) A foamed sheet using an aqueous resin such as an aqueous emulsion, which has an uneven pattern created by a chemical embossing method and has excellent surface strength, stain resistance, chemical resistance, etc. possessed by an ultraviolet curable resin. A foam sheet utilizing the performance can be obtained. (2) Since no plasticizer is used, there is no bleeding and no large amount of black smoke is generated during incineration. Therefore, the present invention exhibits excellent practical effects in applications of building materials such as wallpaper and flooring materials.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a foam sheet showing an example of the present invention.

[Description of sign]

 DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Resin layer for foaming 3 ... Foaming suppression ink 4 ... General ink 5 ... Printing ink layer 6 ... UV curable resin layer

Continuation of the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B32B 33/00 B32B 33/00 (72) Inventor Yoshiki Inaba 1-5-1, Taito 1-chome, Taito-ku, Tokyo Letterpress Printing Co., Ltd.

Claims (1)

[Claims] 1. A foamed resin layer comprising a base material, a foamed aqueous paint having a surface provided on one side of the base material provided with a concave and convex pattern having concave portions and convex portions by foaming, and A printing ink layer having at least a portion printed with a foam-suppressing ink, and an ultraviolet-curable resin layer obtained by curing an ultraviolet-curable resin with ultraviolet light provided on the printing ink layer, which is a foamed sheet having a laminated structure. The portion printed with the foaming suppressing ink is printed so as to coincide with the concave portion of the foamed resin layer, and the ultraviolet curable resin is cured after the foaming aqueous paint is foamed to form an ultraviolet curable resin layer. A foam sheet characterized by the above-mentioned.