JPS631182B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a panel with excellent fire resistance.

Various types of fire-resistant panels are known that are mainly made of inorganic or organic materials, but the former have the drawbacks of being heavy and difficult to handle, and the latter having poor fire resistance.

The present inventors have conducted repeated research in order to provide a fire-resistant panel that does not have the above-mentioned drawbacks, but they have developed an emulsion made by emulsifying rice husks and/or wheat husks with water and an organic polyisocyanate compound as a binder. The present invention was achieved by discovering that a panel obtained using a mixture of the following as a core material is suitable for this purpose.

The organic polyisocyanate compound used as a binder must be emulsifiable with water, and includes, for example, tolylene diisocyanate, diphenylmethane diisocyanate, polyphenylmethane polyisocyanate, diphenyl ether diisocyanate, naphthylene diisocyanate, hexamethylene diisocyanate, and the like. Polyisocyanate compounds such as isocyanates and modified isocyanate compounds obtained by modifying compounds with polyols, etc., and RO (CH ₂ CH ₂ O) _o H or CH ₂ [COO
Ethylene oxide derivative represented by (CH ₂ CH ₂ O) _o R] ₂ (where R is an alkyl group having 1 to 4 carbon atoms,
n is an isocyanate group-containing product partially reacted with a hydrophilic active hydrogen-containing compound such as (on average 5 to 25). Specifically, a polyisocyanate compound is reacted with a small amount of an ethylene oxide derivative under normal urethanization reaction conditions to obtain an organic polyisocyanate compound that can be emulsified with water. When using a modified isocyanate compound, it can be reacted simultaneously with the polyisocyanate compound to be modified.

This organic polyisocyanate compound is used after being emulsified in advance with an appropriate amount of water. The amount of water varies depending on the water content of the material, molding conditions, etc., but is usually 30 to 500 parts by weight per 100 parts by weight of the organic polyisocyanate compound. Since emulsions react if left standing, they are usually emulsified and mixed immediately before use.

As for the mixing ratio of rice husk and/or wheat husk and organic polyisocyanate compound, it is preferable to use 2 to 50 parts by weight of organic isocyanate per 100 parts by weight of rice husk and/or wheat husk. If it is less than 2 parts by weight, no effect as a binder is observed, and 50
If the amount exceeds the weight part, the product will lose its flexibility and become unsuitable for use.

The rice husks and wheat husks used in the present invention are fibrous materials containing a large amount of inorganic substances, and have appropriate flexibility, water resistance, flame retardancy, and lightness.

In addition, the isocyanate binder used in the present invention has a stronger adhesive strength than other binders, so the amount of binder can be reduced, and therefore a fireproof effect can be achieved in panels mainly made of inorganic materials. Water can be impregnated into the panel after molding, and the fire resistance is superior to non-aqueous systems.

The main materials used in the present invention, rice husks and wheat husks, include wood chips, fiber scraps, buckwheat hulls, wheat flour, plant scraps such as buckwheat flour, inorganic fibers, inorganic granules such as perlite grains, borax, Up to 50 parts by weight, preferably 5 to 30 parts by weight, of an auxiliary material selected from inorganic materials such as gypsum can be mixed with 100 parts by weight of the main material, thereby improving economy, fire resistance, and toughness. You can obtain a panel that is excellent in terms of: At this time, the mixing ratio with the binder is 2 to 50 parts by weight per 100 parts by weight of the mixture of the main material and the auxiliary material.

The binder and the material are mixed by a method such as spraying the emulsified binder with a spray device onto the material stirred with a ribbon mixer, and this mixture is spread on or between the surface materials, and the press temperature is increased.
The panel is molded under molding conditions of 50 to 200°C and a press pressure of 0.1 to 50 Kg/ ^cm2 . As surface materials, all materials normally used for panels can be used, including iron plates, aluminum plates, wood plates such as plywood, kraft paper, asbestos paper, asphalt-impregnated paper, cloth, various nonwoven fabrics, rock wool, glass wool, and various plastic films. etc. are used.

Example 1 10 parts by weight of binder A [diphenylmethane diisocyanate-ethylene oxide type, trade name PBA1042, manufactured by ICI] was added to 100 parts by weight of rice husk with a moisture content of 5 to 6% (weight %, hereinafter expressed as %). Mix the emulsion with 8 parts by weight of water and heat a sandwich panel made of iron plate on one side and kraft paper on the other side to a temperature of 150.
℃, pressure 30Kg/ ^cm2 , thickness 10mm, core material density
It was molded to 0.6 g/cm ³ . The steel plate side of the panel was exposed to flame at 800℃ for 10 minutes, but no smoke or ignition was observed.

Example 2 Mixture of rice husks and buckwheat husks (mixture ratio 100/
20 parts by weight, water content 3-4%), an emulsion of 10 parts by weight of binder A and 10 parts by weight of water was mixed with 100 parts by weight,
Sandwich panels made of iron plate on one side and asbestos paper on the other side were prepared under the same conditions as Example 1, with a thickness of 10 mm and core density.
It was molded to 0.6 g/cm ³ . The iron plate side of the panel was exposed to flame at 800°C for 10 minutes, but no smoke or ignition was observed.

Comparative Example Binder B [polyphenylmethane polyisocyanate (NCO content 31-32%) 550 parts by weight, polypropylene glycol (molecular weight 2000) 250 parts by weight, dioctyl phthalate was added to 100 parts by weight of rice husk with a moisture content of 5 to 6%. A reaction product consisting of 200 parts by weight and 10 parts by weight of a reaction product that cannot be emulsified with water] was mixed, and a sandwich panel made of one side of iron plate and one side of kraft paper was heated to a thickness of 10 mm at a temperature of 150°C and a pressure of 30 kg/ ^cm2 . , and the core material density was 0.6 g/cm ³ . The iron plate side of the panel
As a result of being exposed to flame at 800℃ for 10 minutes, flame irradiation 5
Minutes later, a fire ignited from the gap between the iron plate and the core material.

Claims (1)

[Claims] 1 100 parts by weight of a material made by mixing 100 parts by weight of rice husks and/or wheat husks with 0 to 50 parts by weight of one or more types of vegetable waste and inorganic substances, and 2 to 50 parts by weight of an organic polyisocyanate compound that can be emulsified with water. A fire-resistant panel obtained by sandwiching a mixture of water and an emulsion between surface materials, heating and press-molding the mixture.