JPH02235704A - Flame-retarded timber - Google Patents

Abstract

PURPOSE:To provide flame-retarded timer having enough flame retardance by a method wherein timbers in araucaria family are impregnated with the predetermined amount of partial reactional product of dicyandiamide, phosphoric acid, boric acid and water. CONSTITUTION:Timbers in araucaria family are impregnated with 100kg or more solid per one cubic meters of the timber of partial reactional product of dicyandiamide, phosphoric acid, boric acid and water. Araucaria is the general name of timbers in araucaria family such as agathis or the like and agathis is preferable for flame-retarded timber. The partial reactional product contains guanylurea phosphate, which is produced by reacting dicyanamide with phosphoric acid, guanylurea phosphate, which is produced by reacting said guanylurea phosphate with boric acid, un-reacted dicyandiamide and the like. Since the partial reactional product can evenly impregnate to the timber, the preferable amount of impregnation is 500kg or more by solution per one cubic meters of the timber. If said amount is below 100kg, enough improvement effect of flame retardance is not obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to flame-retardant wood, and in particular, by using wood from the Araucaceae family, it is possible to impregnate a large amount of flame retardant, and the flame retardance is significantly improved. It was designed to improve the performance.

[Prior Art] Traditionally, wood has been made flame retardant by impregnating various flame retardants into the wood. Examples include phosphorus-based flame retardants. However, the above-mentioned halogen-based flame retardants generate toxic gases during combustion, which poses an unfavorable problem in terms of health and safety, and the inorganic phosphorus-based flame retardants have the disadvantage of having a small flame retardant effect.

Therefore, in place of these flame retardants, it has recently become known that partial reaction products of dicyanamide, phosphoric acid, boric acid, and water are effective as flame retardants that impart flame retardancy to wood. (JP-A-57-70-178, JP-A-61-179242, etc.). This has the effect of preventing the wood from igniting, and also forms a hard carbonized layer on the surface layer of the wood during combustion, thereby slowing down the burning rate of the wood.

[Problems to be Solved by the Invention] However, the above-mentioned flame retardant is difficult to dissolve in water, so it has a drawback that it is difficult to impregnate wood. For this reason, it has not been possible to obtain flame-retardant wood that can be impregnated with a large amount of flame retardant and has high flame retardancy, and there is still no flame-retardant wood that has passed the Ministry of Construction's grade 1 non-combustible or semi-non-combustible. has not been realized.

Therefore, an object of the present invention is to solve the above-mentioned problems and provide a flame-retardant wood having sufficient flame retardancy.

[Means for Solving the Problems] The present invention involves impregnating wood of the Araucaceae family with a partial reaction product of dicyandiamide, phosphoric acid, boric acid, and water in a solid content of 100 kg or more per 1.3 wood. This was the solution.

[Effect] By using the wood of the Araucaceae family as the wood, the amount of the partial reaction products of dicyandiamide, phosphoric acid, boric acid and water impregnated with the wood is 1.3 in terms of solid content.
This significantly increases the weight to over 100 kg per unit, which significantly improves the flame retardancy and makes it possible to obtain flame-retardant wood that satisfies the Ministry of Construction's "semi-incombustible" grade.

The present invention will be explained in detail below.

The Araucifera used in the present invention includes Agathis alba Foxy, Agathis;
A. philippinensis ga
It is a general term for wood belonging to the Araucaceae family such as Araucaceae, and agathis is particularly preferred because it can be impregnated with a large amount of flame retardant and there is no local variation in impregnated state or impregnated concentration.

In addition, Araucifera is preferred because it has a low ignitability because it contains a small amount of resin in its wood, but there are rare cases where it contains resin, so it must be sorted out before being impregnated with a flame retardant. It is desirable to leave it there. In addition, the wood of the Araucaceae family has relatively few abnormal tissues and often has a regularly arranged and undisturbed structure, so it is suitable for preventing or suppressing the destruction of the carbonized layer of the wood during combustion. used. This wood may be either heartwood or sapwood.

Further, the partial reaction products of dicyandiamide, phosphoric acid, boric acid and water are as described above in JP-A No. 57-701.
It is a flame retardant described in JP-A No. 78 and JP-A-61-179242. This mainly consists of guanylurea phosphate produced by the reaction of dicyanamide and phosphoric acid, the guanylurea phosphate-boric acid product produced by the reaction of this guanylurea phosphate with boric acid, and the unreacted guanylurea-boric acid product. It contains dicyandiamide, phosphoric acid, boric acid, etc., and for example, it is prepared as an aqueous solution with a concentration of 20% by weight, but the concentration of the partial reaction product of dicyandiamide, phosphoric acid, boric acid, and water is 20% by weight. It is not limited to %.

Here, phosphoric acid is a general term for all phosphorus oxyacids, such as H, IPO. , H 3 P O s, H, P
O. -}110, H+PtO'r, H 4P *O e
, HPOs, polyphosphoric acid, and mixtures thereof. Also, boric acid is B (OH)
,,}IBO,,HB03,H*B40? , B
t 0 3 and mixtures thereof. Furthermore, the term "partial reaction product" as used herein means that not all of the components have undergone chemical change, but at least 50%, preferably about 80 to 95%, have reacted.

In addition, the weight ratio of the total amount of dicyandiamide and phosphoric acid to boric acid (dicyanoamide and phosphoric acid/boric acid) in this flame retardant is about 60/40 to 90/10, but the phosphoric acid guanylurea produced is In terms of having higher solubility, about 6
Approximately 5/35 to 75/25 is preferable.

This partial reaction product of dicyandiamide, phosphoric acid, boric acid, and water is impregnated into the wood of the Araucaceae family in a solid content of 100 k9 or more per 1 m3 of wood, resulting in particularly high flame retardancy and "semi-nonflammable" wood can be achieved,
It is preferable to impregnate with a solution of 500k9 or more per lI3 of wood, since it can be impregnated evenly. If it is less than 100k9, the effect of improving the flame retardance of wood cannot be sufficiently obtained, which is not preferable.

Next, a method of impregnating the above-mentioned wood with this flame retardant will be explained.

First, it is preferable to dry the wood before impregnation.

Drying may be natural or artificial drying, but the moisture content should be 9 to 1.
It is preferable to dry the film until it reaches 5% because impregnation with the flame retardant can be carried out smoothly and a large amount of the flame retardant can be impregnated.

For impregnation, a pressure impregnation method using an autoclave or the like is usually employed. Specifically, wood is placed in an autoclave and once heated to 160*xHg (-600xyr
After depressurizing the autoclave for about 30 minutes under a reduced pressure of approximately Impregnate the wood with a combustion agent. At this time, in order to smoothly impregnate the wood with the flame retardant in the amount in the above range, a pressure of 1.2 to 3.
It is preferable to set the condition to about 0 MPa.

After impregnating the wood with the flame retardant in this manner, the wood is further dried to obtain the desired flame retardant wood. At this time, it is desirable to dry the wood with the end of the wood sealed so that the impregnated flame retardant does not volatilize and only moisture is removed, and the end of the wood is not cracked due to drying. . The end of the end may be sealed by a conventional method, and a method of applying a coating material containing tar or the like to an epoxy resin-based synthetic resin is preferably used. Drying can be carried out so that the moisture content of the wood is about 8 to 12%, and usually at a vacuum degree of 0.1 to 10%.
Vacuum heating drying is performed under conditions of approximately Torr and temperature of approximately 60 to 80°C.

The flame retardant wood obtained in the above manner has the above flame retardant impregnated into the wood of the Araucaceae family, so the amount of flame retardant impregnated is significantly greater than that of conventional flame retardant wood. can be impregnated with several times more flame retardant than conventional methods. Araucous cedar also has the advantage of being less flammable because the wood contains less resin. In addition, the wood of the Araucaceae family is
It has a very regular structure with no disturbances, and therefore it is possible to prevent or suppress the destruction of the carbonized layer even during combustion. In this way, by using wood from the Araucaceae family and impregnating it with a large amount of the above-mentioned flame retardant, it was possible to obtain flame-retardant wood with high flame retardancy, something that could not be achieved with conventional wood. It is also possible to obtain flame-retardant wood that satisfies the "semi-incombustible" grade. If such flame-retardant wood is used as various wooden building materials such as doors, wall materials, flooring materials, etc., it is possible to delay the ignition or spread of fire in the event of a fire, thereby securing time for evacuation and firefighting activities. This will greatly help in life safety and property protection. Furthermore, this flame-retardant wood retains the inherent advantages of wood (texture, beauty, light weight, etc.) and is highly usable as a building material with a rich wood feel. In addition, there are no safety problems such as the generation of toxic gas, and it has good termite and antiseptic properties, and has the same corrosion resistance and moisture absorption properties as other materials. It also has great production advantages, such as being able to be mass-produced.

[Example] According to the conditions shown in Table 1, wood was impregnated with a flame retardant. The flame retardant described in JP-A No. 57-70178 was used, and the wood used was a heartwood with a diameter of 50xx. Also included is wood at 160 ixH
g (-600 mml { g) for 30 minutes, then immersed in a flame retardant and heated at a pressure of 1.5 MPa for 40 minutes.
We adopted a method of impregnation by applying pressure for a period of time. The measurement results of the amount of flame retardant impregnated are the average values of the results of several experiments.

(The following is a blank space) As is clear from Table 1, it was found that when agathis, a member of the Araucaceae family, was used as the wood, it was possible to impregnate a very large amount of flame retardant, and moreover, when agathis was used,
There was also little variation due to several experiments. On the other hand,
In Comparative Examples 1 to 8 in which wood from a species other than Araucaceae was used, the amount of flame retardant impregnated was small.

Generally, the impregnation of a flame retardant into wood is influenced by the porosity and permeability of the wood, and it is said that wood with a large porosity can be impregnated with a large amount of a flame retardant. Generally, the porosity is proportional to the specific gravity if the water content is constant. Therefore, Comparative Example 1 has a specific gravity similar to that of Araucaceae.
If there is no difference in the permeability of the flame retardant between the 7 tree species, the amount of impregnation should be about the same as that of Arauciana cedar, but from the experimental results, it is clear that the amount of impregnated wood is about the same as that of Aracoma cedar and this Japanese Patent Application Laid-Open No. 57-7017.
It can be seen that the combination with the flame retardant described in No. 8 exhibits specific behavior.

In addition, in Comparative Example 9 in which a flame retardant other than the agent described in JP-A-57-70178 was used, the amount of impregnated flame retardant was small compared to using agathis in the wood, and sufficient flame retardancy was obtained. I couldn't get it.

Furthermore, according to "Nanyo Wood", page 41 (written by Shoji Sudo, published by Chikyu Publishing), wood of the Araucaceae family, such as agathis, is not classified as having good drug-impregnating properties; It can also be seen that the combination of agathis and the flame retardant disclosed in JP-A-57-70178 is unique.

(Example of Test Piece) In Experimental Example 1, a [quasi-noncombustible] test was conducted using flame-retardant wood obtained by impregnating agathis with a flame retardant described in JP-A-57-70178. This test was conducted according to the method described in Ministry of Construction Notification No. 1231 and No. 1372.

The test results showed that this flame-retardant wood satisfied the "semi-incombustible" grade.

[Effects of the Invention] As explained above, the flame-retardant wood of the present invention contains a partial reaction product of dicyandiamide, phosphoric acid, boric acid, and water in wood of the Araucaceae family in a solid content of 100 k9 or more per wood Is3. Since it is impregnated, it has the advantage of being able to impregnate a large amount of flame retardant and achieve high flame retardancy.

This makes it possible to create flame-retardant wood with a "quasi-incombustible" grade, which has not been possible with conventional wood. In addition, since it retains the inherent advantages of wood (texture, beauty, light weight, etc.), it can be used as a building material with increased flame retardancy without sacrificing its texture. In addition, because we use wood from the Araucaceae family that has a low resin content, it has low ignitability, and because Araucacea has a regularly arranged tissue structure with few abnormal tissues, it prevents tissue destruction during combustion. It also has the advantage of being able to be suppressed. In addition, due to the excellent characteristics of the flame retardant, there are no safety issues, and it has good anti-termite and antiseptic properties, and has the same corrosion resistance and moisture absorption properties as materials, and is suitable for industrial use. It also has the advantage of being mass-producible.

Claims (1)

[Claims] Araucaceae wood contains dicyandiamide, phosphoric acid,
The partial reaction product of boric acid and water was added to the wood in a solids amount of 1
A flame-retardant wood characterized by being impregnated with 100 kg or more per m^3.