JPS5939391B2 - Flame retardant synthetic building materials - Google Patents

Description

[Detailed description of the invention] FIELD OF THE INVENTION This invention relates to flame retardant synthetic building materials.

BACKGROUND ART Conventionally, wood is a typical organic material, and Portland cement is a typical inorganic material, which have been widely used as building materials, and each has advantages and disadvantages.

That is, wood has excellent strength, light weight, and workability, but is vulnerable to fire, and inorganic wood materials, although strong against fire, are heavy and have extremely poor workability.

Perlite board, gypsum board, silicon board, and pulp cement board are known as flame-retardant and highly workable materials that compensate for the shortcomings of these art materials, but some However, it has the disadvantage that it has poor impact resistance and its nail retention strength is close to zero.

Composite materials using fibrous substances to improve processability are also known.

Fibrous substances are usually used as reinforcing materials, and there is a positive correlation between the amount of fiber and the strength within a certain range.

This varies depending on the type, diameter, length, specific gravity, etc. of the fibers, but normally in the case of asbestos, if the total amount of matrix and fibrous material is taken as 100 parts, a linear relationship is shown for the fiber content from 0 to 25 parts. , 50 to 60, the bending strength shows an increase, but beyond this, the strength tends to gradually decrease.

Furthermore, results showing almost the same tendency were obtained when pulp was blended as a reinforcing material.

In addition, the strength varies depending on the type of fiber used.
It is generally known that when organic fibers are used, the processability of the composite material is significantly improved.

On the other hand, when inorganic fibers are used, they are several steps inferior to those using organic fibers in terms of processability and nail retention, but when using inorganic fibers with large diameters, such as glass fibers and rock wool, on the micron order, Things like asbestos are inferior, but things like asbestos, which are on the millimicron order, are improved to some extent.

Incidentally, a pulp cement board is known as a typical example of a composite material formed using organic fibers as a reinforcing material.

This uses Portland cement as a matrix and a small amount of inorganic additives such as serpentine powder or cabbage, and also has a pulp content of 10 to 15%, and has a combustibility equivalent to class 2 flame retardant.

In addition, by using a large amount of pulp and other long fibers, impact resistance that could not be obtained with conventionally commercially available inorganic flame-retardant building materials, asbestos-cement building materials, silicon boards, pulp cement boards, gypsum boards, etc. The impact strength is about 2 to 4 times higher, and flame retardancy and other properties can be maintained by inserting cheesecloth or the like in a layered or net-like manner and adjusting the amount of mixed organic matter so that the total amount of organic matter is 25 parts or less. It has been found that the impact strength can be improved by 4 to 10 times compared to conventional materials, that is, to the same level as wood.

The present invention was made in view of the above circumstances,
The purpose of the present invention is to provide a building material that has properties similar to those of wood and can maintain flame retardancy.

Hereinafter, the present invention will be explained in detail with reference to figures and tables.

In general, endothermic reactants are known as substances added to obtain flame retardant or non-combustible properties.
As a result of various experiments, the inventor found that the endothermic reaction was 200'C~6.
Select a substance that occurs at 00°C, such as magnesium hydroxide, ferrous hydroxide, ferric hydroxide, aluminum hydroxide, zinc hydroxide, magnesium carbonate, aluminum carbonate, iron carbonate, zinc carbonate, silicon hydroxide, etc. is.

Any one type or a mixture of two or more types of these endothermic reactants can be used.

In addition, there are fibrous substances that provide reinforcing properties, light weight, and nail retention strength, and specific examples of these fibrous substances include inorganic fibers such as asbestos, glass fiber, rock wool, carbon fiber, and whiskers. Examples of organic fibers include natural cellulose fibers, which are collectively referred to as pulp, nylon fibers, polypropylene fibers, vinylon fibers, ataryl fibers, and ester fibers.

Of course, one type of these fibrous substances may be used or two or more types may be used in combination.

The flame-retardant synthetic building material of the present invention is formed by blending the above-mentioned endothermic reaction substance and fibrous material.

According to the inventor's experiments, an endothermic reaction substance was used as a matrix, and the total amount of the matrix and fibrous material was 100%.
%, the blended amount of fibrous substance is 0 as mentioned above.
A linear relationship is shown from 50% to 25%, and an improvement in bending strength is shown from 50 to 60%, so the blending ratio within the above range was adopted depending on the purpose.

The endothermic reactant and fibrous material as described above were blended and stirred, put into a mold and pressed, and then removed from the mold and dried to obtain a building material in the desired shape as a plate.

The building material obtained in this way has a flame retardancy test (JIS A 1321) that is equivalent to class 1 flame retardancy even when pulp is added up to 25 parts, and the texture and feel of the surface shows that it is Gives a softness similar to that of wood, and a sweet taste.

In addition, in terms of workability, it was found that the feel of the material is extremely similar to that of wood when nailing, sawing, planing, carving with a knife, or drilling with a chisel.

This effect is due to the use of the various endothermic reactants mentioned above as a matrix.

Specific examples will be described below.

Example 1 The raw materials used are 470 parts by weight of magnesium hydroxide, 400 parts by weight of ferrous sulfate, and 130 parts by weight of pulp.

First, use a commercially available mortar mixer to mix magnesium hydroxide and p.
After stirring the ulp for 2 minutes, ferrous sulfate was added to generate ferrous hydroxide, and the mixture was stirred for another 3 minutes, then put into a mold, pressed at a pressure of 50 kg/ffl, and then removed from the mold and dried. Obtained building materials.

The final composition of the product using the raw materials used above is 60% magnesium hydroxide (the same applies below), 20% ferrous hydroxide (part of the magnesium hydroxide in the raw materials used reacts with ferrous sulfate). and generate.

In addition, magnesium sulfate is produced as a reaction product, which is dissolved in water during stirring of the raw materials and discharged out of the product together with the water during press pressurization.
% composition.

Example 2 Raw materials used: 470 parts by weight of magnesium hydroxide, 400 parts by weight of ferrous sulfate, 97 parts by weight of Pulp, and 33 parts by weight of cheesecloth.
50k as in Example 1 by mixing part by weight as a long fiber material.
After pressing at a pressure of g/crj, the mold was removed and dried to obtain a building material.

The final composition of the product is 60% magnesium hydroxide and 20% ferrous hydroxide as a matrix.
%, other fiber materials include pulp 15%, cheesecloth 5%
The composition is as follows.

Table 1 shows a comparison of the building materials of Examples 1 and 2 with other existing building materials.

Note that in Examples 1 and 2 above, no resin was added.

By the way, the existing pulp cement board (JISA5414
) (containing pulp of 15%) and the product of Example 1 according to the present invention. The results of a heating test are shown in FIGS. 1 and 2.

As is clear from Table 1 and Figures 1 and 2, the building material of the present invention is a durable building material with excellent workability and sufficient strength and thermal properties comparable to pulp cement boards. I can do it.

By the way, as mentioned above, in order to pass the 1st class flame retardant test, the amount of pulp blended must be up to 25% by weight, but this is not limited to cellulose pulp; organic fibers, such as polypropylene fibers,
Synthetic fibers such as vinylon fibers may be used, and organic substances such as latex and emulsions may be mixed with the above-mentioned suitable fibers.

In short, it is sufficient if the total amount of organic matter is 25 parts or less.

In addition, if a building material that passes JIS flame retardancy test grade 2 is acceptable, the blending ratio of organic fibers can be up to 45%, and for flame retardant grade 3, the blending ratio of organic fibers is 63%. Persons in charge are allowed.

At this time, magnesium hydroxide is substituted for the pulp.

In addition, in the JIS flame retardant test class 2, the condition is that the area tdθ of the part beyond the standard temperature curve is 100°C or less, but as is clear from Figure 3, Example 1
t when the pulp content is set to 45% in the product of
dθ is 85° C., which fully satisfies this condition.

Furthermore, in the JIS flame retardancy test grade 3, the area tdθ of the part beyond the standard temperature curve must be 350°C or less, but as is clear from Figure 4, the product of Example 1 Even when it is set to 63%, tdθ is 340℃
, and fully satisfies that condition.

Also in this case, G and magnesium hydroxide are substituted for the pulp.

On the other hand, since the building materials of Examples 1 and 2 have relatively high water absorption rates,
The rate of dimensional change from bone dry to saturated is large.

In order to reduce the rate of dimensional change, it depends on the type of matrix used, but by mixing various emulsions or latex in several coefficients, it is possible to create a product that can withstand use even in areas where water is used. It will be done.

Particularly when using even a portion of an iron-based matrix, there are restrictions on the mixed use of these resins, but in this case, organic solvent type neoprene phenol resin is most effective.

Table 2 shows the dimensional change rate and water absorption rate when resin was added.

Example 3 438 parts by weight of magnesium hydroxide, 400 parts by weight of ferrous sulfate, and 130 parts by weight of pulp were used as raw materials, and 32 parts by weight of neoprene phenol resin was added as a resin.

The resin is added by mixing and stirring the main raw materials after a predetermined time has elapsed, as in Example 1, and then stirring for an additional 3 minutes.

The final composition of the building material obtained as described above is 55% magnesium hydroxide, 20% ferrous hydroxide, 20% pulp as fiber material, and 5% resin.

As is clear from the above explanation, according to the present invention, building materials are obtained by mixing a substance that undergoes an endothermic reaction at 200°C to 600°C with a fibrous material, so the obtained building materials have characteristics similar to those of wood. It is an extremely excellent flame-retardant synthetic building material that has properties that allow it to maintain flame retardancy.

[Brief explanation of drawings]

Figure 1 is a diagram of the heating characteristics of the pulp cement board, Figure 2 is a diagram of the heating characteristics of the building material of Example 1, and Figures 3 and 4 are diagrams of the heating characteristics when the content of pulp is changed. It is a line diagram.

Claims (1)

[Claims] 1. A flame-retardant synthetic building material made by press-molding a mixture of magnesium hydroxide, ferrous sulfate, and fibrous material.