JPH03220393A - Nonflammable paper - Google Patents

Abstract

PURPOSE:To obtain nonflammable paper capable of satisfying a Japanese industrial standard having excellent softness and processability comprising specific mica powder, polyarylate fiber, fibrillar polyarylate pulp obtained from pulverizing of said polyarylate fiber and fibrous sepiolite. CONSTITUTION:(A) 40-95 pts.wt. mica powder (e.g. golden mica) having <=1000mu weight-average flake diameter and >=10 weight-average aspect ratio is dispersed into water together with (B) 2-10 pts.wt. polyarylate fiber having 1-20mm length, (C) 2-10 pts.wt. fibrillar polyarylate pulp obtained by pulverizing the component B and (D) 3-30 pts.wt. fibrous sepiolite having 0.5-30 mm length, and further 1-20 pts.wt. fibrous hydrated magnesium, etc., and resultant dispersion is combed up on a round net, etc., then dried with dehydration, thus heat-treated at 300-350 deg.C to afford the aimed nonflammable paper.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to non-combustible paper.

(Prior Art) Non-combustible paper has been used as base paper for building materials, wrapping paper, and insulating materials for high-temperature transformers, etc. for the ceilings, walls, and floors of houses. However, the current situation is that combustible organic materials are used as materials for conventional non-combustible paper.

In order to impart non-flammability or flame retardancy to such flammable organic materials, organic phosphorus or the like is usually used in post-processing or internal addition to impart non-flammability or flame retardancy. In addition, some paper products such as fiberboards and wallpapers are impregnated with flame retardants or subjected to surface treatment by spraying.

(Problem to be Solved by the Invention) However, none of the conventional methods for imparting nonflammability or flame retardance to combustible organic materials is sufficient to make the combustible organic materials nonflammable or flame retardant. Moreover, it has the disadvantage that the flame retardant used as a processing agent is harmful to the human body.

Furthermore, methods for imparting nonflammability or flame retardancy to paper processed products have drawbacks such as poor flame retardant performance and the generation of harmful gases.

Therefore, an object of the present invention is to provide a noncombustible paper that overcomes the above-mentioned drawbacks, can pass the flame retardant class 2 of the Japanese Industrial Standard JISA H22, which is defined for flame retardant materials, and is flexible and has excellent workability. .

(Means for solving problems) It is.

40-95 parts by weight of mica powder with a diameter of 10 or more, a length of 1-95 parts by weight
This is achieved by providing a non-combustible paper consisting of 2 to 10 parts by weight of polyarylate fibers having a diameter of 20 mm and 3 to 30 parts by weight of the biolite.

In the present invention, the mica powder includes gold mica, white mica,
Examples include synthetic mica, and its shape has a weight average flake diameter of 1000μ or less, a weight average aspect ratio of 10 or more, and preferably a weight average flake diameter of 75μ.
It is 0μ or less, and the weight average aspect ratio is 20 or more. When mica powder having a coulometric average flake diameter of more than 1000 μm or a weight average aspect ratio of less than 10 is used, it becomes difficult for the obtained noncombustible paper to maintain its shape. The weight average flake diameter and weight average aspect ratio of mica powder can be calculated using the following formula.
“Here, is the average diameter of one mica flake, τ,
denotes the average thickness of the flakes, m, and the total weight of the flake group having the shape of τ1. L+ tt, I*+
■1. τI%+In also has the same meaning. D...
The average diameter of the flakes represented by D, . . . Dfi is determined by the following formula.

π(-)'' = area of 1 flake The blending amount of mica powder is 40 to 95 parts by weight, and 40 to 9
Preferably, it is 0 parts by weight. Japanese Industrial Standards regarding non-flammability if less than 40 parts by weight! @J I S A 13
If the amount exceeds 95 parts by weight, the non-combustible paper will peel off between the eyebrows, and it will be difficult to obtain a good non-combustible paper.

As the polyarylate fiber, for example, the product name E-Pectran J provided by Kuraray Co., Ltd. can be used as is. In order to maintain the form of mica powder having the above shape as paper, the fiber length may be in the range of 1 to 20 ID11, and there is no limit to the fiber diameter, but it is preferably in the range of 5 to 50 microns.

Polyarylate pulp is obtained by fifurlating the above-mentioned polyarylate fibers by crushing or the like.

Although polyarylate fibers and polyarylate pulp have excellent heat resistance, since they are organic substances, their nonflammability is impaired in high heat conditions, so it is preferable to mix them in as little amount as possible; I have no choice but to. The blending amount of polyarylate fiber and polyarylate pulp is such that it cannot be made into paper, and 1
If it exceeds 0 parts by weight, problems will arise in nonflammability.

As the fibrous Seviolite, for example, the trade names "Sepiolite S, M, and L" provided by Nippon Talc Co., Ltd. can be used as they are. In order to maintain the form of mica powder having the above shape as paper, the fiber length may be in the range of 0.5 to 30 IIll, and there is no restriction on the fiber diameter. Fibrous Seviolite acts as a laminated material for mica powder during paper making, and other materials are evenly attached to this fibrous Seviolite to make paper, resulting in non-combustible paper of uniform thickness and material. can get. The blending amount of fibrous Seviolite is 3 to 30 parts by weight, and 5 to 2 parts by weight.
Preferably it is 5 parts by weight. If it is less than 3 parts by weight, it will not be able to maintain its paper form, and if it exceeds 30 parts by weight, the strength of the paper will decrease.

In the present invention, mica powder, polyarylate fibers, polyarylate pulp, and fibrous Seviolite are dispersed in water, and this dispersion is screened onto a round net or fourdrinier,
After dehydration and drying, a portion of the polyarylate fibers is melted by heat treatment at 300 to 350° C., acts as a glue material, and noncombustible paper is obtained.

In addition to the above four materials, fibrous hydrated magnesium compounds and polyvinyl alcohol fibers can be added to improve nonflammability and shape retention. As the fibrous hydrated magnesium compound, for example, the product name "MOSHIDE" provided by Ube Industries, Ltd. can be used as is.

The fibrous hydrated magnesium compound is Mg・5Mg0・8
．． It is represented by the chemical formula FI, 0, and because it is fibrous, it acts as a laminated wood during papermaking and can enhance its nonflammability due to the endothermic action when the crystal water in the molecules is desorbed and evaporated during heating. The blending amount is preferably 1 to 20 parts by weight, particularly preferably 3 to 15 parts by weight. Polyvinyl alcohol fibers are made of polyvinyl alcohol! Examples include fibers made of polyvinyl alcohol modified by acetalization, copolymerization, etc., and there are no particular restrictions on the fiber diameter and fiber length. The blending amount is preferably 2 to IO parts by weight. When polyvinyl alcohol fibers are used, when the paper is dried at 100-150° C. after papermaking, the polyvinyl alcohol fibers melt and act as a glue material.

Furthermore, in the present invention, fibrous or fibrous inorganic substances such as glass fibers, acicular wollastonite, and carbon fibers,
Powdered inorganic substances such as talc, clay, calcium carbonate, and black smoke can be added within a range that does not impair nonflammability.

(Function) According to the present invention, the paper obtained by dispersing specific amounts of banjo powder, polyarylate fiber, polyarylate pulp, and fibrous sepiolite in water and making the paper has excellent nonflammability and flame retardancy. In addition, it has excellent heat insulation, air permeability, electrical insulation, and processability, making it effective for conventional uses such as flame-retardant wallpaper, ceiling materials, sound-absorbing materials, electrical insulation materials, and sound-proofing materials. Can be used.

(Examples) Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples in any way.

Examples I to 7 and Comparative Examples 1 to 7 Muscovite (Kurarite Mica, manufactured by Kuraray Co., Ltd.) or phlogopite (Sujirite Mica, manufactured by (Sister) Kuraray Co., Ltd.), fiber length of 5μ and fiber diameter of 30μ polyarylate fiber, which is
Polyarylate pulp, fibrous sepiolite with a fiber length of II and a wtw diameter of 10μ, a fibrous hydrated magnesium compound, or polyvinyl alcohol fiber with a fiber length of 3+am and a fiber diameter of 5μ (V P B -
105, manufactured by Kuraray Co., Ltd.) in the proportions shown in Table I.
Put LOOG and 1000ml of water into a disintegrator (manufactured by Kumagai Riki Kogyo Co., Ltd.), disperse it in water, and then mix it into 25X 25X 40
cm-sized talapi soba was transferred to a paper-making machine (manufactured by Kumagai Riki Kogyo Co., Ltd.), water was added to make a dispersion of 1512, and the mixture was then subjected to paper-making. Next, the obtained paper product was dehydrated and dried at a temperature of 110°C. For paper products that do not contain polyvinyl alcohol fibers, the temperature is further increased to 320°C.
It was hot pressed for 15 minutes at a temperature of .

The properties of the obtained paper product were as shown in Table 1.

Note that the density was calculated from the dimensions and weight of the sample, and the tensile strength was measured in accordance with JISP8113. The flame retardancy test method was based on the Mezkel burner method of JISA1322, and the heating time was 3 minutes, and the carbonization length, afterflame, and residual dust were measured to determine pass/fail.

The following blank space (effects of the invention) According to the present invention, the Japanese industrial layer IJ I S A 1
A non-combustible paper that can pass the 2nd grade flame retardancy of 322, is flexible and has excellent workability is provided.

Claims (1)

[Claims] 40 to 95 parts by weight of mica powder having a weight average flake diameter of 1000 μ or less and a weight average aspect ratio of 10 or more, and 2 to 1 polyarylate fibers having a length of 1 to 20 mm.
0 parts by weight, 2 to 10 parts by weight of fibril-shaped polyarylate pulp obtained by crushing the polyarylate fibers, and length 0
．． A noncombustible paper comprising 3 to 30 parts by weight of 5 to 301 fibrous sepiolite.