JPS59199585A - Incombustible gypsum board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a gypsum hoard with excellent nonflammability.

Gypsum ports have been widely used as interior materials because of their various features such as flame retardancy, easy workability, and low cost.

In particular, flame retardancy is the most outstanding feature of gypsum board, and in recent years, fire prevention requirements have led to a demand for gypsum board with even higher flame retardancy.

However, gypsum board can be roughly divided into the gypsum core and the layer/layer.
'i,: Consists of a port base paper that covers the control section. Among these, the core material of the gypsum is stone/Yl, which is originally nonflammable;
is the main component, so the non-combustibility of gypsum board depends exclusively on Hoard Kawara Paper.

Conventional base paper for gypsum board is made from combustible waste newspapers and waste Danhole paper, so when manufacturing non-combustible gypsum board, conventional base paper for gypsum board was replaced with ordinary base paper for board as described in -. and asbestos paper have been used. However, these are not only expensive, but also have fatal flaws such as insufficient adhesion with the IiI plaster core and a decrease in the strength of the stone/niihod itself. It didn't work out.

For this reason, a noncombustible gypsum board has also been proposed using a board base paper made of ordinary Hoard Kawahara paper with an asbestos layer. However, asbestos is a substance that is harmful to the human body, and due to its nature, the manufacturing process that handles such substances requires extreme care, resulting in very high production costs.11. I have no choice but to do so.

As a result of intensive studies to solve these problems, the present inventors discovered that port base paper containing Ta acid has excellent nonflammability, and completed the present invention.

Accordingly, the present invention provides a noncombustible gypsum board in which a gypsum core is covered with board base paper containing boric acid and/or borate.

The present invention will be explained below.

The gypsum board of the present invention is no different from a normal gypsum board except that the hoard base paper contains boric acid and/or a borate (hereinafter referred to as boric acid, etc.).

The boric acid used in the present invention may be in any form such as orthoboric acid, meta-octacid, tetraboric acid, pentaboric acid, and heboric acid.

Further, as the boric acid, salts of the various boric acids mentioned above can be used. Zunawajigaru salts include alkali metal salts such as lithium salts, sodium salts, potassium salts, rubidium salts, and cesium salts; helium salts, magnesium salts,
Salts of alkaline earth metals such as calcium salts, strontium salts, barium salts; titanium salts, vanadium salts, chromium salts,
Examples include salts of transition metals such as molybdenum salts, manganese salts, iron salts, cobalt salts, nickel salts, palladium salts, copper salts, zinc salts, and aluminum salts; and ammonium salts.

The port base paper containing boric acid, etc. used in the present invention can be produced by any method. For example, one method is to use an aqueous solution of boric acid or the like during paper production. In other words, waste paper is used as the main raw material, and a small amount of pulp, etc. is added to it, which is disintegrated in a halver, and then beaten in a refiner, etc., and then an appropriate amount of the above-mentioned boric acid, etc. is added along with additives such as sizing agents and pigments to form a circular mesh. The paper can be made and dried using a paper machine such as a paper machine.

In addition, as another method, it is of course possible to manufacture this by coating, penetrating, impregnating, drying and tightening an aqueous solution such as boric acid on the surface of a general base paper for ports.

As another method, the boric acid impregnation operation can be carried out at the same time as the production of the stone/t-board 1 without preparing the boric acid-containing base paper in advance as described above.

In other words, gypsum board is usually made by adding various additives such as fillers, curing time regulators, strength reinforcing agents, adhesive reinforcing agents, waterproofing agents, dispersants, etc. to hemihydrate gypsum powder, which is the main raw material, and water, and then thoroughly kneading the mixture. The obtained gypsum slurry is poured out between the top and bottom sheets of gypsum port base paper, which are continuously fed out, and is pressed with rolls to form a hoard. However, in order to manufacture the gypsum board of the present invention, when preparing the gypsum slurry as described above, boric acid or the like may be added to the slurry together with the other additives mentioned above (it is better to knead it in advance. The slurry of boric acid, etc. (which is naturally thought to be in the form of an aqueous solution) is poured out between the gypsum hoard base paper as described above and comes into contact with the board Kawahara 1flE, and the board is immediately removed. It penetrates into the base paper, and as a result, a noncombustible gypsum board equivalent to using gypsum port base paper pre-contained with @acid or the like is obtained.

In addition, as another method, the non-combustible gypsum of the present invention can be obtained by applying, penetrating, and impregnating an aqueous solution such as boric acid on the surface of a normal gypsum hoard prepared by using general gypsum board base paper and then drying it. Of course you can get a board.

In the present invention, the amount of boric acid, etc. that should be contained in the hoarded paper is 100 parts by weight (hereinafter simply referred to as "parts") of the paper.
1 part or more, preferably 2 to 5 parts.

In addition, when using the method of adding to gypsum slurry, the main raw material is gypsum hemihydrate.

08 parts or more, preferably 1.5 to 4.0 parts
Department.

If the amount added is less than the above value, it will not be possible to achieve the effect of the present invention of imparting nonflammability of A':1, and even if it is added in excess of the above value, no further effect can be expected. Not only that, but there is a possibility that the adhesion between the gypsum port and the Hoard Kawahara paper may be deteriorated.

The gypsum hoard coated with the gypsum port base paper containing boric acid, etc. of the present invention not only has extremely excellent nonflammability, but also has excellent non-combustibility as shown in the examples below. There are no disadvantages such as the unavoidable adhesive force with the gypsum core or the decrease in the strength of the gypsum (horde itself).Also, during manufacturing, the base paper for general gypsum board was not used. Of course, there is no difference from the case in which it is used, and it can be easily manufactured.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Comparative Example-1 100 parts of hemihydrate gypsum powder, 80 parts of water, 0.5 part of starch, and 0.1 part of potassium sulfate were quickly and thoroughly mixed to form a slurry. The slurry was weighed on two scales, weighing 250g/
It was poured between base paper for board m' and allowed to solidify. After solidification, dry at 60'C for 24 hours to obtain gypsum board).

Comparative Example 2 In Comparative Example 1, gypsum hoard was obtained in the same manner as in Comparative Example 1, except that one of the two board base papers was replaced with a commercially available asbestos laminated board base paper with a weight of 350 g/'. .

Comparative Example 2 is a non-combustible gypsum laminate (as specified by the Ministry of Construction).
It is commercially available as a certified non-combustible No. 1oo4).

Example 1 In Comparative Example 1, the base paper for boats was soaked in a 2% orthoboric acid (hereinafter simply referred to as boric acid) aqueous solution for about 1 hour to impregnate it with boric acid, and then dried at 60°C for 24 hours. A gypsum board was obtained in the same manner as in Comparative Example 1 except for the above. The amount of boric acid contained in the base paper was approximately 2 parts per 100 parts of the base paper, which was calculated from the amount of water pumped into the base paper.

Example 2 Gypsum board 1 was obtained in the same manner as in Example 1 except that a 5% boric acid aqueous solution was used.

Example 3 A gypsum board was prepared in the same manner as in Comparative Example 1, except that 1.5 parts of powdered boric acid was added to 100 parts of hemihydrate gypsum powder to form a slurry. I got it. It was found that the boric acid added to the slurry material migrated to the board base paper used, and it was found that about 2 parts of rdl acid was contained per 100 parts of the base paper.

Example 4 A gypsum board was obtained in the same manner as in Example 3 except that 4 parts of powdered boric acid was added.

Comparative Example-3 A gypsum board was obtained in the same manner as in Example-3 except that 5 parts of boric acid (powder) was added. After drying, this gypsum board easily peeled off due to poor adhesion between the base paper and the gypsum core.

Comparative Example-4 A moth-eaten pattern was pressed on the surface of the base paper for the asbestos laminated board of gypsum hoard obtained in Comparative Example-2, and then a white paint mainly composed of vinyl acetate emulsion, calcium carbonate, and titanium oxide was applied on top of it. It was applied and dried at 60°C for 24 hours to obtain a decorative gypsum board. In addition, Comparative Example 3 is a non-combustible gypsum laminate (general rule certified non-combustible No. 1004) specified by the Ministry of Construction.
It is commercially available as No.

Example-5 The gypsum hoard obtained in Example-1 was treated in the same manner as in Comparative Example-3 to obtain a decorative gypsum hoard.

For the gypsum hoards and decorative stone π hoards obtained in Comparative Examples-1 to 4 and Examples-1 to 5 above, JISA1
Table 1 shows the results of the base material test and surface test conducted in accordance with the crazy flammability test method.

As is clear from the table, the gypsum hoard of the present invention and the decorative gypsum hoard derived therefrom have the same superiority (1 [It can be seen that it is flammable.

Claims (1)

[Claims] (1) A noncombustible gypsum board in which a gypsum core is covered with board base paper containing boric acid and/or borate.