JPH04360949A - Incombustible lightweight plaster board - Google Patents

Abstract

PURPOSE:To obtain an incombustible lightweight plaster board without spoiling fire-proof performance, by covering the core material of plaster for a main body, with plaster board sheet paper with mixed flame-retarding disposal pulp, to be bonded to each other. CONSTITUTION:The core material of plaster for a main body is covered with plaster board paper-sheets to be respectively bonded as a front side paper sheet and a rear side paper sheet, and a lightweight plaster board is composed. As the front side paper sheet, in place of a normal plaster board paper-sheet, a paper sheet with a specified quantity of mixed flame-retarding disposal pulp with ammonium polyphosphate or the like is used.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to noncombustible, lightweight gypsum board.

0002

BACKGROUND OF THE INVENTION In recent years, gypsum board has been widely used as an interior base material due to its fire retardant properties, sound insulation properties, workability, etc. The gypsum board consists of a core material consisting of gypsum, the main material, and a small amount of one or more types of auxiliary materials such as fiber reinforcing materials, foaming agents, adhesion aids, gypsum hardening regulators, lightweight aggregates, etc., and a core material that is bonded together. It is composed of covered gypsum board paperboard and is relatively lightweight compared to other building materials, but as buildings become taller, further weight reduction is required in terms of transportability, workability, etc. It is requested.

0003

[Problem to be solved by the invention] The fire resistance of gypsum board is usually affected by the amount of gypsum in the core material that makes up the gypsum board. If the volume is maintained and the weight of the gypsum board is made lighter, a problem arises in that the fire protection performance decreases. This is due to the fact that the fire resistance of gypsum board is such that in the event of a fire, the approximately 21% crystallized water contained in gypsum absorbs latent heat at 100-200°C and releases the crystallized water, and until the crystallized water disappears, gypsum board This is because it exhibits a heat shielding effect that keeps the back surface temperature below the crystal water release temperature.

[0004] Therefore, commercially available gypsum boards containing a large amount of gypsum and having a high specific gravity can be used in the event of a fire, even if the gypsum board paperboard that adhesively coats the gypsum-based core material is made of combustible pulp. The gypsum core material suppresses combustion and maintains the fireproof performance of the gypsum board, but in the case of lightweight gypsum boards made by reducing the amount of gypsum, the ability to suppress combustion is reduced due to the small amount of gypsum in the core material. will decrease.

[0005] Incidentally, the noncombustible gypsum board that is certified by the Ministry of Construction as noncombustible No. 1003 and is commercially available to the general public is
The front and back surfaces of a gypsum core material that does not contain organic fillers are adhesively coated with gypsum board paperboard made of combustible pulp.
The specifications include a thickness of 12 mm and a specific gravity of 0.8 or more. In addition, noncombustible gypsum board, which is certified as noncombustible gypsum board No. 1004 by the Ministry of Construction as a noncombustible gypsum board with a low specific gravity, uses noncombustible fibers such as rock wool in the gypsum board paperboard that adhesively covers the surface of the gypsum core material. 40% or more of paper is used, and the back side is adhesively coated with paperboard for gypsum board made of ordinary combustible pulp, with a thickness of 9 mm and a specific gravity of 0.7.
The above specifications are as follows.

[0006] In all of the above cases, non-combustible lightweight gypsum boards with a specific gravity of 0.7 or more and 0.7 or less are not commercially available. The object of the present invention was made in view of the above, and it is an object of the present invention to provide a non-combustible, lightweight gypsum board with a specific gravity of 0.7 or less, which does not impair fire protection.

[0007]

[Means and operations for solving the problems] In order to achieve the above object, the present invention provides a gypsum board consisting of a core material mainly made of gypsum and a paperboard for gypsum board covering the core material with adhesive. To provide a noncombustible lightweight gypsum board characterized by having flame-retardant treated pulp mixed into the paperboard for the gypsum board.

[0008] According to this configuration, the volume is maintained by reducing the amount of gypsum and using foam agents, lightweight aggregates, etc., and the gypsum board paperboard mixed with flame-retardant pulp is adhesively coated on the lightweight gypsum-based core material. As a result, combustion of the paperboard for gypsum board is suppressed in the event of a fire, and the fire protection performance of the lightweight gypsum board obtained by reducing the amount of gypsum can be maintained without deterioration. Flame-retardant treated pulp is cellulose fiber that has been flame-retardant treated with a phosphorus compound, a halogen compound, an antimony compound, a boric acid compound, etc. using a commonly used method. It is 20% or more in paperboard for plasterboard, preferably 40 to 70%. 2
If the amount of mixed paper is less than 0%, the flame retardant treatment effect will be small, and if it is more than 70%, it will be uneconomical.

[0009] The grammage weight of the paperboard for plasterboard used is 1
It is 50-350 gr. If it is less than 150 gr/m2, the strength required for a lightweight gypsum board will not be achieved, which is undesirable, and if it is more than 350 gr/m2, it will be uneconomical. Further, the surface of the paperboard for gypsum board mixed with flame retardant treated pulp to be adhesively coated with a core material mainly composed of gypsum is not limited to one surface of the core material, but other surfaces may also be adhesively coated.

Furthermore, the thickness of the lightweight gypsum board is 9 mm or more, and its apparent specific gravity is 0.4 to 0.7. If the thickness is 9 mm or less and the specific gravity is 0.4 or less, there will be difficulties in the nail retention force, strength, etc. required of the gypsum board, and furthermore, there will be problems such as a decrease in fire protection.

[0011]

[Embodiment] An embodiment of the present invention will be described below. (Comparative Example 1) Each of the cover and back paper weighs 230 g
A gypsum board paperboard made of a conventional combustible pulp of A calcined gypsum slurry kneaded with the weight part of water is poured and formed into a plate shape, and after hardening, it is dried to produce a lightweight gypsum board (weight 6.6 kg/m2) with a thickness of 12 mm and a specific gravity of 0.55. Ministry Notice No. 18
Flame retardancy tests were carried out including the base material test and surface test specified in No. 28. Table 1 shows the results. (Example 1) The cover of Comparative Example 1 was the same as Comparative Example 1, except that instead of ordinary gypsum board paperboard, a 230-gram paper mixed with 30% flame-retardant pulp treated with ammonium polyphosphate was used. The above flame retardancy test was conducted in exactly the same manner. Table 1 shows the results.

0012
Table-1
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Base material test Surface test
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Comparative example 1 Fail
Fail ━━━━
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Example 1 Pass Pass
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━━ Note: The criteria for determining non-flammability are:
According to Ministry of Construction Notification No. 1828.

The surface of the gypsum core material is adhesively coated with a gypsum board paperboard mixed with the flame-retardant pulp of the present invention, and the back side is adhesively coated with a gypsum board paperboard made of a conventional combustible pulp, and the specific gravity is 0. 55 lightweight gypsum board was tested as a base material,
Although it passed the surface test, a lightweight gypsum board with a specific gravity of 0.55, in which the front and back surfaces of the gypsum core material were adhesively coated with conventional gypsum board paperboard made of combustible pulp, was also made by reducing the amount of gypsum to reduce weight. As shown in Table 1, both tests failed.

[0014]

[Effects of the Invention] According to the above structure of the present invention, fire retardancy is not impaired by adhesively covering the core material mainly made of gypsum with paperboard for gypsum board mixed with flame-retardant pulp. It becomes possible to provide non-combustible lightweight gypsum board.

Claims (1)

[Claims] Claim 1: In a gypsum board consisting of a core material mainly made of gypsum and a gypsum board paperboard adhesively covering the core material, a flame retardant treated pulp is mixed into the gypsum board paperboard. Lightweight, non-combustible gypsum board.