JPS5828084B2 - Flame retardant composition for wood - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flame retardant composition for wood comprising borax, boric acid, diammonium phosphate, thiourea and sodium dioctyl sulfosuccinate.

Wood is widely used as a building material because it is easy to work with, has good texture, is lightweight, and has unique strength properties, but it has the disadvantage of being easily ignited and combustible.

In recent years, the demand for fire-resistant buildings has become stronger and stronger, and making wood flame-retardant has become an even bigger issue.

Various flame retardants have been studied to make wood flame retardant, but none of them can be said to be fully satisfactory.

For example, halides such as ammonium chloride, ammonium bromide, and chlorinated paraffin have excellent flame retardant effects, but have the drawback of being highly toxic.

The same goes for the halides, but known flame retardants such as ammonium phosphate, ammonium borate, guanidine phosphate, and antemonium oxide have weak permeability into wood, so when treated with the flame retardant, wood The disadvantage is that although the surface area of the material is made flame retardant, the interior cannot be made flame retardant.

As a result of repeated research in order to develop a composition that imparts excellent flame retardancy to wood, the present inventor discovered that a composition consisting of borax, boric acid, diammonium phosphate, thiourea, and sodium dioctyl sulfosuccinate was developed. The flame-retardant composition has an excellent penetrating effect on wood, and when wood is treated with the flame-retardant composition, the flame-retardant composition quickly penetrates into the interior of the wood, thereby causing the above-mentioned effects. The present invention has been completed based on the remarkable fact that the above object can be easily achieved and the composition has extremely low toxicity.

That is, in the flame retardant composition of the present invention, when it is made into an aqueous liquid and wood is immersed in the aqueous liquid, due to the strong penetrating action of sodium dioctyl sulfosuccinate,
The flame retardant composition quickly penetrates deep into the interior of the wood, making the wood efficiently flame retardant.

Furthermore, the flame retardant composition of the present invention does not contain any halides or heavy metal oxides, so it has extremely low toxicity.

In the above, as an example of wood treatment with a flame-retardant composition, the case where wood is immersed in an aqueous solution of a flame-retardant composition was given as an example, but it is also possible to apply or spray the aqueous solution onto the wood. Even if it is used, the effects of the present invention will not be impaired in any way.

In the flame retardant composition of the present invention, borax improves flame retardancy and imparts insect repellency, and boric acid improves flame retardancy and imparts insect repellency, and improves weather resistance and rot preservative of wood. diammonium phosphate improves fire resistance and improves the adhesion of the composition to wood; thiourea improves fire resistance and improves the adhesion of the composition to wood.

As mentioned above, dioctyl sodium sulfosuccinate has the effect of quickly permeating the flame retardant composition into wood.

The proportion of each component used in the flame retardant composition of the present invention is not particularly limited, but for example, 50 to 100 parts of boric acid to 100 parts (by weight, hereinafter) of borax.
In terms of flame retardancy, insect repellency, weather resistance, antiseptic properties, adhesion to wood, etc., when using proportions of 300 to 500 parts of diammonium phosphate and 150 to 225 parts of thiourea. Particularly remarkable effects are exhibited.

In addition, dioctyl sodium sulfosuccinate is borax,
The proportion is preferably 0.05 to 0.2 parts per 100 parts of the total amount of boric acid, diammonium phosphate and thiourea.

In other words, if the amount of boric acid used exceeds the above range, there is a risk that boric acid will crystallize and precipitate, and even if the amount used is increased, flame retardancy, insect repellency, etc. will not improve much; As a result, the flame retardancy decreases, and even if the amount of diammonium phosphate used exceeds the above range, the fire resistance and adhesion to wood will not improve much, and conversely, if the amount is decreased, the fire resistance will deteriorate. If the amount of thiourea used exceeds the above range, thiourea may crystallize and precipitate, and even if the amount used is increased, the fire resistance and adhesion to wood will not improve much, and on the other hand, if the amount is decreased, This is because fire resistance deteriorates.

Moreover, if the amount of sodium dioctyl sulfosuccinate used is larger than the above range, the solubility of sodium dioctyl sulfosuccinate will deteriorate, and if it is smaller, the rate of penetration of the flame retardant composition into wood will decrease.

To prepare the flame retardant composition of the present invention, borax, boric acid, diammonium phosphate, thiourea, etc., alone or together, are dissolved in water to form an aqueous solution, sodium dioctyl sulfosuccinate, etc. Since it is sparingly soluble in water, it is first dissolved in a water-soluble alcohol such as methanol or ethanol, and an alcoholic solution of sodium dioctyl sulfosuccinate is strained. The composition may be added to an aqueous solution of ammonium diphosphate, thiourea, etc., stirred and mixed to obtain the composition in the form of an aqueous liquid, and if necessary, dried to form a powder.

In making wood flame retardant with the flame retardant composition of the present invention, the amount of the flame retardant composition (solid content) per 1m8 of wood is about 30 g or more, although it varies depending on the material of the wood.
In particular, if the amount is about 50 to 100 parts, a remarkable flame retardant effect will be exhibited.

It goes without saying that the flame retardant composition of the present invention can be applied not only to natural wood but also to so-called improved wood (for example, plywood) obtained by subjecting natural wood to some kind of mechanical or chemical treatment.

Next, the flame retardant composition of the present invention will be explained with reference to this example.

Example 5 At 10 o'clock in water heated to 0.degree. C., 400 g of borax, 350 g of boric acid, 17 diammonium phosphate, 2 and 800 g of thiourea were sequentially added and stirred to dissolve.

Next, 60 g of sodium dioctyl sulfosuccinate was added to 500 g of methanol, stirred and dissolved, and the obtained methanol solution of sodium dioctyl sulfosuccinate 1
00g was added to the above aqueous solution and thoroughly stirred to obtain an aqueous solution of a flame retardant composition.

Suck up the aqueous liquid of this flame retardant composition with a dropper and
□n lauan plate (25 (l1771X 25CrIL)
One drop (approximately 0.05 cc) of above and below was added to examine the permeability of the aqueous liquid.

The aqueous liquid spread quickly on the lauan plate and stopped spreading after 15 seconds.

From this result, it was confirmed that this flame retardant composition had extremely excellent permeability.

Next, a lauan board (25 (m x 25 □) with a thickness of 1 Qii) was immersed in the aqueous solution of the flame retardant composition, and after being left at room temperature for one day, the lauan board was taken out from the solution and the liquid adhering to the lauan board was removed. After wiping it off, it was dried at room temperature.

After drying, the lauan plate was divided into two equal parts in the thickness direction, and the thickness was 5+n.
I got two lauan boards.

When we analyzed both the front and back sides of this 5n thick lauan board, we found that
The content of the flame retardant composition on the front side (the side that was in contact with the aqueous liquid of the flame retardant composition) and the back side (the side that was not in contact with the aqueous liquid) of the lauan board was almost the same.

Next, the lauan board treated as described above is JIS A
When subjected to the heating test specified in 1321, there was no melting of the specimen and no cracks on the back side of the specimen, the afterflame time was 8 seconds, and the area surrounded by the exhaust temperature curve and the standard temperature curve (unit: 'CX min.) was 245, and the smoke generation coefficient was 113, passing grade 3 flame retardancy.

Comparative Example 400 g of borax, 350 g of boric acid, 1.7 g of diammonium phosphate and 800 g of thiourea were added in sequence to water heated to 50°C at 10 o'clock, and dissolved by stirring.

Suck up this aqueous solution with a dropper and place one drop (approximately 0.05 cc) on a 10 mm thick lauan plate (25 crrL x 251).
dripped.

The aqueous solution gradually spread on the Lauan plate, and even after 20 minutes, σ did not stop spreading.

From this result, it was confirmed that the permeability of this composition was significantly inferior to that of the flame retardant composition of the above example.

Next, add a lauan plate (15 CI) with a thickness of 10 mm to the above aqueous solution.
rL x 5crrL) was immersed and left at room temperature for one day.The lauan plate was taken out from the liquid draining process, and after wiping off the liquid adhering to the lauan plate, it was dried at room temperature.

After drying, the lauan board was divided into two equal parts in the thickness direction to obtain two lauan boards each having a thickness of 5 mm.

When both the front and back sides of this lauan plate were analyzed, the content of chemicals (borax, boric acid, diammonium dibasic phosphate, and thiourea) on the front side (the side that was in contact with the aqueous solution) was 21 g, but on the back side. (The drug content of the aqueous solution (the side that was not in contact) was 8 g.

Next, the lauan board treated as described above is JISA
When subjected to the heating test specified in 1321, the surface side was found to be flame retardant class 3 (passed) as in the case of the above example.
On the back side, the afterflame time was long, and the area and smoke generation coefficient of the part surrounded by the exhaust temperature curve and the standard temperature curve were large, and the flame retardant grade 3 was not passed.

Claims (1)

[Claims] 1. A flame retardant composition for wood comprising borax, boric acid, diammonium phosphate, thiourea and sodium dioctyl sulfosuccinate. 2 The usage ratio of each component of the flame retardant composition is 10 parts of borax
In contrast, boric acid is 50 to 100 parts by weight, diammonium phosphate is 300 to 500 parts by weight, thiourea is 150 to 225 parts by weight, and sodium dioctyl sulfosuccinate is borax, borax, etc. The flame retardant composition for wood according to claim 1, wherein the amount is 0.05 to 0.2 parts by weight based on 100 parts by weight of the total amount of acid, diammonium phosphate and thiourea.