JPS5852828B2 - What's going on? - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing fiberboard with good flame retardancy.

Fiber boards are widely used as interior materials, wall materials, etc. of buildings, but there is a strong desire to make them flame retardant from the standpoint of safety against fires, and various methods have been tried.

First, there are three proposed methods for applying flame retardants, which can be roughly divided into: (a) dipping method, (p) coating method and spray method.

Although the dipping method has advantages such as uniform application to the fiber laminate and excellent permeability, there is a limit to the amount of application due to squeezing with a mangle, so it is difficult to obtain the sufficient flame retardancy and hardness required for the product. It has disadvantages such as not having a large size, and requiring large equipment such as an immersion bath and a mangle.

Since the coating method is applied at a very high viscosity, it has drawbacks such as very poor permeability and the need for relatively expensive equipment.

The spray method is the cheapest in terms of equipment, does not take up much space, is easy to operate, and has a high processing speed.However, the only drawback is that the spray method Examples of such problems include insufficient or uneven penetration of the processing agent into the laminate.

In particular, when the fiber laminate is made of hydrophobic synthetic fibers such as polyester, polyamide, polyolefin, etc., and the treatment bath contains an inorganic flame retardant in addition to the binder as in the method of the present invention, poor or uneven penetration may occur. Because it is difficult to uniformly diffuse the flame retardant into the body, a major problem arises in that the desired flame retardant properties cannot be achieved.

The present inventors conducted intensive studies to obtain a fiber board with excellent flame retardancy and excellent uniform permeability of the treatment agent into the interior of the fiber laminate, while employing the spray method. It has become clear that the permeability and uniformity of the treatment agent can be significantly improved by applying an appropriate amount of an aqueous solution containing the treatment agent in advance, and the present invention has been achieved.

That is, the present invention first applies water or an aqueous solution containing a penetrant to the fiber laminate at a weight of 20 to 120 g to a synthetic fiber laminate having a weight per square meter of 200 to 800 g to sufficiently penetrate the fiber laminate. After this, an aqueous dispersion consisting of a polymeric binder, aluminum hydroxide, ammonium polyphosphate and/or ammonium polyphosphate is sprayed to the fiber laminate in a solid amount of 50 to 200% by weight. This is a method for manufacturing a flame-retardant fiber board.

According to the present invention, an inexpensive and hard flame-retardant fiber board can be manufactured with simple operations.

The fiber laminate referred to in the present invention is made of hydrophobic synthetic fibers such as polyester, polyamide, polyvinyl alcohol, polyolefin, etc., and is preferably in the form of a nonwoven fabric.

The fiber laminate has a basis weight of 200 to 800.9/m, preferably 300 to 650.9/m.

2oog/, (below is not strong enough, while 800g/rr
If it is more than 1, the weight will increase unnecessarily, which is unfavorable from the viewpoint of workability and economy.

In the present invention, the step of applying water or an aqueous solution containing a penetrant to a synthetic fiber laminate is particularly effective when the fiber laminate is made of hydrophobic synthetic fibers such as polyester, polyamide, polyolefin, etc. This step is essential when an organic substance such as a polymeric binder and an inorganic substance such as aluminum hydroxide, ammonium polyphosphate, or ammonium polyphosphate amide are used simultaneously.

Flame retardants exhibit their full flame retardant effect only when they are all uniformly permeated and dispersed into the fiber laminate.
If water or an aqueous solution containing a penetrant is not applied in the method of the present invention, only the polymeric binder that is highly compatible with hydrophobic fibers will quickly penetrate into the fiber laminate, and aluminum hydroxide, ammonium polyphosphate, and ammonium polyphosphate amide. The penetration of inorganic flame retardants is inevitably delayed, resulting in an unbalanced application of the composition ratio, in other words, local application of the flame retardant, resulting in a significant loss of flame retardant effect.

That is, in the method of the present invention, by pre-wetting the inside of the fiber laminate with water or an aqueous solution containing a penetrant, the inorganic flame retardant, which is less compatible with hydrophobic fibers, can easily penetrate into the fiber laminate. This is something that we are trying to encourage.

In the present invention, the effect is naturally greater when the penetrant is included than when water is used alone.

The types of penetrants used in this case are nonionic ones, sulfuric esters of higher alcohols having 8 to 20 carbon atoms, anionic ones such as sodium alkylbenzenesulfonate, and alkyl trimethyl ammonium having 8 to 20 carbon atoms. Any cationic type such as chloride or alkyldimethylbenzyl ammonium chloride may be used, but
It is desirable to use a surfactant that has good compatibility with the aqueous dispersion applied afterwards, and from that point of view, nonionic surfactants are preferred, such as polyoxyethylene alkyl ether, polyoxyethylene alkylphenol ether, and the like.

The appropriate concentration range for the penetrant is 1 to 10 g/l.

The amount of water or penetrant aqueous solution applied is 20 to 20% to the fiber laminate.
120 weight ratio, preferably 40 to 80 weight ratio, more preferably 45 to 60 weight ratio.

If the amount applied is more than 120% by weight, a large amount of aqueous solution will remain on the surface of the fiber laminate, which will actually impede the permeability of the aqueous dispersion applied afterwards, so the amount applied must be strictly controlled. Must be protected.

The aqueous solution may be applied simply by a spray method.

A polymeric binder and an aqueous dispersion of aluminum hydroxide and ammonium polyphosphate and/or ammonium polyphosphate amide are spray applied to the fiber laminate pretreated in this way. From the viewpoint of properties and flame retardancy, it must contain a polymeric binder, aluminum hydroxide and at least one of ammonium polyphosphate and ammonium polyphosphate amide.

Polymeric binders include polyvinyl acetate, polyacrylic acid ester, SBR, polyvinyl chloride,
Examples include polyvinylidene chloride, polyacrylamide, polyethylene or copolymers of these, aminoplast resins, etc. Polyvinyl acetate or 70% polyvinyl acetate, which does not particularly impede the flame retardant effect and has high hardness, may be used.
Copolymers containing at least their weight percent are preferred.

Aluminum hydroxide contains 3 moles of water of crystallization in its molecules, and of course works as a flame retardant due to its dehydration and heat absorption effects, but it is also cheap and works as a filler for polymeric binders, making it ideal for use in fiber boards. It also plays a role in exhibiting hardness.

Ammonium phosphate has the general formula (wherein n is an integer in the range of 20 to 400, and rn
/n is a value between 0.7 and (,1, and the maximum value of m is n
+ 2), and the main chain consists of a P-0-P type chain.

What is ammonium polyphosphate amide?
In contrast to ammonium chloride, part of the main chain has a P-NH-P type, and part of the side chain has a P-NH group.

Both ammonium polyphosphate and ammonium polyphosphate amide contain a high content of P and exhibit excellent flame retardant effects, but ammonium polyphosphate amide is particularly superior in terms of water resistance.

The blending ratio of the polymer binder, aluminum hydroxide, and ammonium polyphosphate and/or ammonium polyphosphate amide is 20 to 40 parts by weight of the polymer binder,
Preferably 30-350-35 parts by weight aluminum 40
~70 parts by weight, preferably 55-655-65 parts by weight
The amount of ammonium IJ phosphate and/or ammonium polyphosphate amide is 5 to 20 weight percent, preferably 5 to io weight percent.

It should be noted that coloring agents and other additives may be added to the treatment bath as needed, but it is important not to impair the excellent flame retardant effect that is a feature of the present invention.

These treatment baths are always applied in the form of aqueous dispersions and are always spray applied.

In this case, the appropriate viscosity is 20 to 100 CPS.

The amount of adhesion is 50 to 200 in terms of solid content to the fiber laminate.
The weight range is preferably 90 to 150 weight.

Hardness and flame retardancy are poor under 50 weight, and under 20 weight.
At 0 weight, the drying process and other manufacturing processes become complicated,
This results in the drawback of high raw material costs.

In addition, in the method of the present invention, after the water or penetrant aqueous solution applied in the pretreatment step has sufficiently penetrated into the interior of the fiber laminate, the next spray treatment with a treatment agent containing a flame retardant is performed. The time between and flame retardant treatment is usually 10
The duration is from seconds to 10 minutes, but is not particularly limited thereto.

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

In addition, all parts or parts in the examples mean parts by weight.

Hardness and flame retardancy were determined by the following test method.

(1) Hardness: JIS-6301 spring type hardness tester (JIS Hardness Te5ter manufactured by Shimadzu Corporation)
Measure the back side of the sample (the reaction side of the treated side).

The larger the number, the harder it is.

(2) Flame retardancy: Using an alcohol lamp with a flame length of 2 crrl, apply indirect flame to the bottom of a vertically erected sample for 1 minute.

The results will be evaluated in the categories 1 to 3 below.

Category 1: Completely burnt down.

Category 2: It catches fire, but half of the sample burns and self-extinguishes.

Category 3: No flaming.

(3) Penetration: The degree of penetration is determined visually and evaluated in categories 1 to 3.

Category 1: Penetrates only into the very surface of the fiber laminate.

Category 2: Penetrates to the middle layer of the fiber laminate.

Category 3: Penetrates to the back side of the fiber laminate.

Example 1, Comparative Examples 1 and 2 A polyester laminate with a weight of 520 g per square meter and a thickness of 5.5 mm - dollar punch nonwoven fabric.

After spraying 500 parts by weight of an aqueous solution containing 3jj/l of a penetrating agent (nonylphenol ether with 12 moles of ethylene oxide) onto a plain woven fabric containing 70 g/m of polypropylene as the base fabric, an aqueous dispersion having the treatment bath composition shown in Table 1 was prepared. 12 after spraying the body with 450 weight and weight type (150 parts)
It was dried at 0°C for 60 minutes.

The results of the hardness, flame retardancy, and permeability of the obtained fiber board are also listed in Table 1.

As a comparative example, when spraying an aqueous solution containing a penetrating agent was omitted (Comparative Example 1), instead of spraying 50 yen, 15
The case of 0% spraying (Comparative Example 2) is also listed in Table 1.

As is clear from Table 1, it is clear that the method of the present invention has excellent permeability, and therefore is also excellent in flame retardancy and hardness of the back surface.

On the other hand, Comparative Examples 1 and 2, which do not satisfy the conditions of the present invention, are inferior in permeability, hardness, and flame retardance.

Example 2, Comparative Example 3 Only the treatment bath composition was changed as shown below, and the other treatments were carried out in the same manner as in Example 1. [Processing bath composition] Polyvinyl acetate ethylene coelectric (copolymerization ratio 80/20) Dispersion ( Active ingredient 50%) 50 parts aluminum hydroxide 35 parts ammonium polyphosphate amide 15 parts water
110 parts (processing bath viscosity)
(80C, P, S) The adhesion amount was 120% in terms of solid content.

The back surface hardness of the obtained fiber board was 90, and both flame retardancy and permeability were good in category 3.

In addition, as Comparative Example 3, the spraying of the aqueous solution containing the penetrant was omitted, and after spraying 450% of the above treatment bath, it was squeezed with a mangle (squeezing pressure 3!?/c1?L), and then treated in the same manner as in Example 1. As a result, the adhesion amount was 85%.

The obtained fiber board had a hardness of 60, and both flame retardancy and permeability were classified as Category 2, which was considerably inferior to Example 2.

Example 3 Polyester laminate with weight per square meter of 500.9 mm and thickness of 5 mm - dollar punch nonwoven fabric, base fabric of polypropylene 7
After spraying 70% by weight of water onto a 0 g/m" plain woven fabric, 400% by weight (140% solids) of an aqueous dispersion having the treatment bath composition shown in Table 2 was sprayed.
It was dried at 200C for 60 minutes.

The results of the hardness, flame retardancy, and permeability of the obtained fiber board are also listed in Table 2.

Example 4 A 1 g/l aqueous solution of sodium sulfosuccinate (anionic penetrant) was sprayed onto the polyester laminate used in Example 3 at 70% by weight, and then an aqueous dispersion having the treatment bath composition shown in Table 2 was applied. 450% by weight (150% solids)
After spraying, it was dried at 120°C for 60 minutes.

The results of the hardness, flame retardance, and permeability of the obtained fiber boards are also listed in Table 2.

Example 5 A 1 g/l aqueous solution of laurylamine phosphate (cationic penetrant) was added to the polyester laminate used in Example 3.
After 0 weight spraying, 450% by weight (150% solids) of an aqueous dispersion having the treatment bath composition shown in Table 2 was sprayed, and the substrate was dried at 120° C. for 60 minutes.

The results of the hardness, flame retardancy, and permeability of the obtained fiber board are also listed in Table 2.

Claims (1)

[Claims] 1. To a synthetic fiber laminate having a weight per square meter in the range of 200 to 800 g, 20 to 120 weight percent of water or a non-solution containing a penetrant is first applied to the fiber laminate to sufficiently penetrate the fiber laminate. After that, a solid content of an aqueous dispersion consisting of at least one flame retardant selected from the group consisting of ammonium polyphosphate and ammonium polyphosphate amide, a polymeric binder, and aluminum hydroxide is applied to the fiber laminate, A method for producing a flame-retardant fiber board, characterized by applying a spray with a weight ratio of 50 to 200.