JPH09176987A - Production of inorganic sheet for backing vinyl wall paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing an inorganic sheet for backing a vinyl wall paper capable of operating a foaming process of a vinyl layer in the production processes of the vinyl wall paper at a higher speed. SOLUTION: This method for producing an inorganic sheet for backing a vinyl wall paper, obtained by coating a synthetic resin containing an inorganic powdery material consisting of aluminum hydroxide as a major component on both of the surfaces of a substrate paper layer, is to impregnate >=5wt.% and <=7.5wt.% synthetic resin containing a sizing agent to each of both surfaces of the substrate paper.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inorganic sheet for backing vinyl wallpaper, and more particularly to an inorganic sheet for backing vinyl wallpaper that enables the foaming process of the vinyl layer in the vinyl wallpaper manufacturing process to be operated at a higher speed. It relates to a manufacturing method.

[Prior art]

Inorganic sheets are widely used as wall covering materials and the like, and are also used as base materials for backing vinyl wallpaper.

Known as an inorganic sheet is a cellulose pulp containing a flame-retardant inorganic powder by a wet papermaking method. As a typical example, there is an inorganic sheet obtained by mixing aluminum hydroxide as an inorganic powder with pulp to make a paper.

Vinyl wallpaper is produced by applying vinyl chloride paste to the surface of flame-retardant paper or an inorganic sheet, heat-treating it to semi-gel the vinyl chloride paste, and foaming / embossing. The wallpaper processing speed has been increasing year by year, but if a base paper with a slow foaming speed is used, foaming failure will occur, resulting in poor embossing and affecting the product's completion.

As a backing paper with improved vinyl chloride paste processability of vinyl wallpaper backing paper, an inorganic sheet characterized in that a coating layer containing an inorganic pigment and a binder as a main component is provided on one or both sides of a base paper ( JP-A-1-
192900), the content of aluminum hydroxide having an average particle size of 0.5 to 1.0 μm is 8 to 30% by weight,
There is known a backing paper having a filler content of 15% by weight or more on one surface when a web is divided into two in the thickness direction, and a vinyl wallpaper using the backing paper (JP-A-1-266298). All of them are characterized in that swelling is less likely to occur due to heat treatment in the vinyl chloride semi-gelling process of vinyl wallpaper. Also known is a flame-retardant backing paper (Japanese Patent Laid-Open No. 221496/1990) in which a filler having an oil absorption of 45% or more is mixed in a paper in an amount of 2.0% or more. It is characterized by preventing the formation of blisters between the backing paper and the vinyl layer in the semi-gelling process. Further, a flame-retardant paper for backing vinyl wallpaper in which the ratio of aluminum hydroxide to the adhesive in the surface coating agent is in the range of 30:70 to 55:45 per absolute dry weight (JP-A-6-81).
(Japanese Patent Publication No. 298) is also known, but its purpose is to prevent swelling and puncture of the vinyl chloride surface. Furthermore, the particle size of aluminum hydroxide is 1 μm or more and 3 μm or less, the content of the inorganic powder is 75% by weight or more and 85% by weight or less, and the density before machine calendering is 0.85.
g / cm ³ or more 0.90 g / cm ³ or less, the thickness direction of the thermal conductivity of the paper is 0.35W / m · K~0.40W / m ·
Flame-retardant paper for backing K vinyl wallpaper (Japanese Patent Application No. 6-23340)
No. 0) is known, but it is the same for the purpose of improving the foaming rate, but since it is not impregnated with a synthetic resin, the means for achieving it is different from the method for producing the inorganic sheet of the present invention. .

[Problems to be solved by the invention]

Conventionally used vinyl wallpaper backing paper is flame-retardant paper treated with a flame-retardant agent, and an inorganic sheet mainly containing aluminum hydroxide. The former is used in the paper to impart required flame-retardant performance. In the latter case, the aluminum hydroxide releases a large amount of water when the paper burns, so that the synthetic resin or the flame retardant It is not impregnated, and usually only a small amount of synthetic resin is applied to the surface in order to maintain the strength of the paper.

Therefore, since the conventional inorganic sheet retains a large amount of air in the web, the air serves as a heat insulating layer, causing insufficient heat transfer in the foaming step during wallpaper processing, resulting in a slow foaming speed. Become. The above-mentioned Japanese Patent Application No. 6-233400 has been proposed as a means for solving such a foaming defect, but the wallpaper processing speed is increasing year by year, and it is not possible to deal with this method alone. .

[0008] Therefore, an object of the present invention is to develop a backing paper for vinyl wallpaper, in which the vinyl layer has a high foaming speed in the foaming step in the vinyl wallpaper manufacturing process.

[Means for Solving the Problems]

[0009] As a result of intensive studies conducted by the present inventors in view of the above situation, in a vinyl wallpaper backing inorganic sheet containing an inorganic powder containing aluminum hydroxide as a main component, a synthetic resin is properly used in a base paper layer. It has been found that the impregnation treatment within the range increases the foaming rate of the vinyl layer. That is, when synthetic resin is impregnated into the base paper layer, the voids in the base paper layer are reduced, so air with low thermal conductivity is replaced with synthetic resin with high thermal conductivity, and the paper layer thickness direction of the backing paper is reduced. It was found that the thermal conductivity of the vinyl chloride was improved and the foaming speed of the vinyl layer was increased.

That is, the present invention relates to an inorganic sheet for backing vinyl wallpaper, comprising a base paper layer containing an inorganic powder containing aluminum hydroxide as a main component, coated with a synthetic resin on both sides. 5% by weight of synthetic resin containing agent
The above is a method for producing an inorganic sheet for backing vinyl wallpaper, which is impregnated with 7.5% by weight or less.

BEST MODE FOR CARRYING OUT THE INVENTION

The inorganic substance used in the present invention is mainly aluminum hydroxide, but depending on other uses, a small amount of inorganic substances such as magnesium hydroxide, talc, titanium oxide, calcium carbonate, kaolin and clay may be used together. good.

As the fiber raw material of the base paper, softwood bleached kraft pulp (NBKP), softwood semi-bleached kraft pulp (N
SBKP), hardwood bleached kraft pulp (LBKP), hardwood semi-bleached kraft pulp (LSBKP), softwood bleached sulfite pulp (NBSP), hardwood bleached sulfite pulp (LBSP), mechanical pulp (MP), thermomechanical pulp (TMP). There are other wood pulps and the like, and one or more kinds of these pulps can be appropriately selected and used. Further, dimensional stability may be improved by blending one or more kinds of synthetic fibers such as polyester fibers and inorganic fibers such as glass fibers into the above fiber raw material.

The inorganic sheet for backing vinyl wallpaper according to the present invention can be easily produced by a conventional wet papermaking method by adding a retention aid or a binder to a mixed slurry of a fiber raw material and an inorganic substance, as appropriate. . The paper machine used may be a cylinder, a short-mesh, a fourdrinier, a birch former, a rotoformer, a hydroformer, etc., and the dryer may be a Yankee type, a multi-cylinder type or a through type.

Examples of the retention aid include cationic polymers such as cationized starch, cationic polyacrylamide, polyethyleneimine, polyamide polyamine epichlorohydrin, cation-modified guar gum, cation-modified polyvinyl alcohol, and other cationic polymers. There is no particular limitation. As the anionic polymer, polyacrylamide, polymethacrylamide,
There is no particular limitation, such as oxidized starch and other anionic polymers. Further, an adhesive such as soluble vinylon fiber or synthetic resin emulsion may be used for the purpose of maintaining the strength of the base paper.

The vinyl wallpaper backing inorganic sheet of the present invention can be obtained by impregnating and applying a synthetic resin to a sheet obtained by mixing fibers and inorganic powder and wet papermaking. As the synthetic resin, for example, one or a combination of two or more of PVA, starch, SBR, melamine, polyacrylic amide, vinyl chloride / ethylene resin, vinyl chloride / ethylene / vinyl acetate resin, etc. can be used. The synthetic resin has a higher thermal conductivity than air, and is not particularly limited. In the impregnation coating treatment, an impregnation method which is usually used for synthetic resins, for example, a size press machine may be used.

In the present invention, the synthetic resin is not particularly limited, but the impregnation rate is 10% by weight or more and 15% by weight or less with respect to the base paper. If the synthetic resin impregnation rate is less than 10% by weight, the desired foaming suitability cannot be obtained, and if it exceeds 15% by weight, the peelability of the base paper is deteriorated.

In the inorganic sheet for backing vinyl wallpaper of the present invention, a sizing agent is added to the coating liquid in order to prevent the paste from penetrating into the base paper when the vinyl wallpaper is applied. If necessary, an internally added sizing agent can be used together at the time of papermaking, but the amount of the internally added sizing agent can be adjusted so that the desired synthetic resin impregnation rate can be obtained by adding the internally added sizing agent, or the surface tension of the impregnating agent or Take measures such as decreasing the viscosity. As the sizing agent to be used, an internally and / or externally added sizing agent such as an alkyl ketene dimer, a styrene acrylic type, a styrene amide type can be appropriately selected and used.

【Example】

The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not of course limited thereto. The percentages shown in the examples and comparative examples all mean% by weight.

Examples 1 and 2 After defibrating bleached softwood kraft pulp (NBKP), it was beaten to a freeness of 300 ml by a conventional method, and aluminum hydroxide ("Hijilite" manufactured by Showa Denko Co., Ltd.) was added as an inorganic powder. To prepare a mixed slurry of pulp fiber and aluminum hydroxide.

Cationizing agent (manufactured by Dick Hercules, "Epinox") 0.1%, anionic polymer compound (manufactured by Allied Colloid, "Percoll 173") 0.01% as a retention aid in the above fiber slurry. Was added to the total weight of the fiber content to prepare a paper stock, and using a laboratory handmade machine, the basis weight was 120 g / m ² , and the density was 1.
A sheet having an aluminum hydroxide compounding ratio of 80% at 0 g / cm ³ was produced.

This sheet was impregnated with SBR type color as a synthetic resin in a solid content of 11% and 14% with respect to the total weight of the paper. The composition of the SBR color is SBR latex ("T-2418C" manufactured by JSR): polyacrylic amide ("PC-305" manufactured by Arakawa Chemical Co., Ltd.): sizing agent ("Hamacoat S-90" manufactured by Misawa Ceramic Chemical).
0G ") = 80:10:10.

By the above method, two kinds of inorganic sheets were prepared: an inorganic sheet having a synthetic resin base paper impregnation rate of 11% (Example 1) and a 14% inorganic sheet (Example 2).

Vinyl chloride paste was applied at 100 g / m ² to these inorganic sheets, half-gelled at 150 ° C. for 30 seconds, and heat-treated at 220 ° C. for 30 seconds to measure the expansion ratio. For the expansion ratio, the thickness (a μm) of the vinyl chloride paste layer after semi-gelling and the thickness (b μm) of the vinyl chloride paste layer after expansion were measured, and the expansion ratio was calculated by b / a. When the expansion ratio was 6 times or more, the evaluation of the foamability was ◯, and when the expansion ratio was less than it, the evaluation was x. The composition of vinyl chloride paste is 70 parts of plasticizer to 100 parts of vinyl chloride.
Parts, calcium carbonate 80 parts, titanium oxide 20 parts, stabilizer 2 parts, foaming agent 12 parts, and diluent 10 parts. Furthermore, in order to evaluate the peelability, the peel strength of the interlaminar peel strength of 60 gf or less was measured according to the method B of the peel strength test method for the lapped layer of paperboard described in JIS-P-8139. , Those less than that were marked x. The results are shown in Table 1.

Comparative Example 1 A vinyl wallpaper was prepared in the same manner as in Example 1 except that the impregnation ratio of synthetic resin was 8% based on the total weight of paper, and the foamability and peelability of this inorganic sheet were evaluated. The results are shown in Table 1.

Comparative Example 2 A vinyl wallpaper was prepared in the same manner as in Example 1 except that the impregnation ratio of synthetic resin was 18% based on the total weight of paper, and the foamability and peelability of this inorganic sheet were evaluated. The results are shown in Table 1.

Comparative Example 3 Fiber slurry containing internally added sizing agent (Arakawa Chemical Co., Ltd., “CS-2”)
80 ") was added in the same manner as in Example 1 except that the synthetic resin-unimpregnated sheet produced in the same manner as in Example 1 was coated with 14% of the synthetic resin based on the weight of the paper. We made vinyl wallpaper by the method, and the foamability of this inorganic sheet,
The peelability was evaluated. The results are shown in Table 1.

[0027]

[Table 1]

As can be seen from Table 1, as shown in Examples 1 and 2, when the synthetic resin content is within the proper range and the impregnation treatment is carried out, both foamability and peelability are good.

On the other hand, as seen in Comparative Example 1, if the synthetic resin impregnation rate is lower than the proper range, the foamability is poor.

Further, as seen in Comparative Example 2, if the synthetic resin impregnation rate exceeds the proper range and a large amount is blended, the peelability is deteriorated.

In Comparative Example 3, the synthetic resin content is within the proper range, but as a result of only applying the conventional surface coating, the amount of synthetic resin permeated into the paper layer is small, and the foamability is poor. .

【The invention's effect】

As can be seen from the above description, according to the present invention, an inorganic sheet for backing vinyl wallpaper is obtained by applying a synthetic resin to both sides of a base paper layer containing an inorganic powder containing aluminum hydroxide as a main component. In the above, by impregnating 10% by weight or more and 15% by weight or less of the synthetic resin applied on both sides into the base paper layer, it is possible to provide a method for producing an inorganic sheet for backing vinyl wallpaper having excellent foamability.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Mina Yoshida, 1-10-6, Shinonome, Koto-ku, Tokyo Shin-Oji Paper Co., Ltd. Shinonome Research Center (72) Inventor, Yoshiaki Kabayama 1-10, Shinonome, Koto-ku, Tokyo No. 6 Shin-Oji Paper Co., Ltd. Shinonome Research Center

Claims (1)

[Claims] 1. An inorganic sheet for backing a vinyl wallpaper, comprising a base paper layer containing an inorganic powder containing aluminum hydroxide as a main component, coated with a synthetic resin on both sides. A method for producing an inorganic sheet for backing vinyl wallpaper, which comprises impregnating a resin in an amount of 5% by weight or more and 7.5% by weight or less.