JPH0681683B2 - Flameproof plywood and manufacturing method thereof - Google Patents

Description

The present invention relates to a flameproof plywood and a method for manufacturing the same. More specifically, the present invention relates to a flameproof plywood that complies with Japanese Agricultural Standards and has a flameproof performance specified by the Fire Service Construction Ordinance, and a manufacturing method thereof.

[Conventional technology]

In the conventional flameproof plywood, the veneer is dipped in a flameproofing agent solution mixed with ammonium phosphate or the like, dried and then bonded with a urea resin adhesive or the like, or the ordinary plywood is impregnated with the above flameproofing agent solution. The flame-proof plywood such as the one after-dried has been manufactured by the so-called dipping method. Since then, a method of adding a flame retardant to an adhesive has been proposed which has improved the complexity of the dipping method, the high equipment cost, and the problem in terms of quality (Japanese Patent Publication No. 45-17313). However, there are problems such as high cost due to the flame retardant material used still very much.

The present inventors have conducted further research on these,
We proposed a method that further improved flame retardancy and early curing and gelation of the adhesive by adding a mixture of alumina fine particles containing melamine and a melamine isomer to the flameproof adhesive (Japanese Patent Application No. 61-139207). ).

[Problems to be solved by the invention]

However, even in the production of this flameproof plywood, it is still susceptible to the working environment temperature. Therefore, in order to maintain the flameproof performance and adhesive performance, the role of the flameproof adhesive as a curing agent (catalytic action)
And the addition ratio of the primary ammonium phosphate having a flameproofing function and the alumina fine particle mixture containing melamine and melamine isomers (melem, melam), which are flameproofing and have an adhesion enhancing property, are appropriately changed. However, it is necessary to maintain the optimum viscosity required for applying to the veneer for plywood. However, under high temperature working conditions such as summer, signs of early curing of the adhesive appear, and if the flameproof plywood production is continued for a long time, the adhesive tends to thicken, and an unstable coating amount occurs. Along with that, the quality of the product also becomes unstable, and further thickening and solidification and adhesion of gelled substances are observed in the gluing machine (spreader) that evenly applies the adhesive to the veneer for plywood and its accessory equipment, adhesive piping, etc. This makes it difficult to clean the spreader at the end of work, resulting in a large reduction in productivity due to time and time required for cleaning. Therefore, as a countermeasure against this, in the conventional plywood production, the production quantity of one lot is considerably limited so that it is completed within the allowable thickening time of the adhesive, and it is still difficult to improve the productivity.

In addition, ammonium monophosphate, which also functions as a hardening agent (catalyst) and flameproofing function of a flameproof adhesive, when packed in a bag and deposited and stocked, it will block due to the aging solidification phenomenon and uniformly prevent flames. It is difficult to mix it with the adhesive as it is, and it is necessary to pulverize each time to pulverize each time, which requires a great deal of labor and labor. Moreover, when there is unevenness in the pulverization, only the solidified ammonium phosphate monobasic is spotted in the flameproof adhesive and applied as it is to the veneer for plywood. Had a problem in that it partially deteriorated and the quality deteriorated.

[Means for solving problems]

The present inventors have conducted extensive studies to solve the above problems and completed the present invention.

That is, the present invention is a urea resin or urea melamine co-condensation resin 50
~ 80 parts by weight and 20 to 50 parts by weight of phenolmiramine co-condensation resin (total of 100 parts of both), 5 to 30 parts by weight of an alumina fine particle mixture containing 10 to 60% by weight of melamine and / or melamine isomers. A flameproof plywood characterized by containing a flameproof adhesive interposed between veneers for plywood, and urea resin or urea melamine co-condensation resin 50 to 80 parts by weight and phenol melamine co-condensation resin 20 To 50 parts by weight (total of 100 parts of both), 5 to 30 parts of an alumina fine particle mixture containing 10 to 60% by weight of melamine and / or melamine isomers.
A method for producing a flameproof plywood, characterized by interposing a flameproof adhesive, which is contained in parts by weight, between the veneers for plywood and performing pressure bonding.

In the present invention, urea resin or urea melamine co-condensation resin
It is an essential requirement that 50 to 80 parts by weight and 20 to 50 parts by weight of a phenol melamine co-condensation resin be mixed and used. By including an alumina fine particle mixture containing melamine and / or melamine isomers in this, the adhesion and flame resistance are further improved, and the thickening and curing phenomena of the adhesive are hardly affected by the working environment temperature. Can be prevented. Further, in the adhesive of the present invention, ammonium chloride alone is sufficient as a curing catalyst, and there is an advantage in that the amount used can be relatively small.

The amount of the alumina fine particle mixture is 5 to 30 parts by weight based on 50 to 80 parts by weight of the urea resin or urea melamine co-condensation resin and 20 to 50 parts by weight of the phenol melamine co-condensation resin (total of 100 parts of both). If it is less than 5 parts by weight, the flameproof property is lowered, and if it exceeds 30 parts by weight, the viscosity is increased and the workability is deteriorated. Further, the alumina fine particle mixture contains melamine and / or melamine isomers in an amount of 10 to 60
Although it is contained in an amount of 10% by weight, if it is less than 10%, the flameproof property is insufficient, and if it exceeds 60% by weight, the viscosity increases and the workability deteriorates.

As the alumina fine particle mixture, for example, recovered catalyst fine particles produced as a by-product from the urea-based melamine production plant can also be used preferably. This is obtained by sieving the alumina catalyst recovered in the production of urea melamine, and the amount of melamine and melamine isomers contained is 2 to 15% by weight, melam 5 to 40%, melem. It is about 1 to 10%, but this component ratio does not need to be so strict.

The particle size of the fine particles is preferably 50 μm or less.

The alumina fine particle mixture is sufficiently dispersed and mixed in urea resin or urea melamine co-condensation resin and phenol melamine co-condensation resin to form a flameproof plywood adhesive. Ammonium chloride is added as a curing catalyst.

In the production of plywood, a flameproof adhesive is attached to the plywood veneer and laminated, and a cold pressure of 5 to 12 kg / cm ² is usually applied for 10 minutes to
After 1 hour, at 6 to 13 kg / cm at 80 to 120 ° C
^A flameproof plywood is obtained by allowing the flameproof adhesive to permeate the veneer to a proper extent and sufficiently adhering it while applying the heat pressure of ² for 20 to 120 seconds.

〔The invention's effect〕

In the bonding process of the normal plywood manufacturing process, just add the preparation operation of the flameproof adhesive at the stage of gluing the adhesive,
Flame-resistant plywood with significantly improved adhesive strength and flame-retardant properties is manufactured, and in particular the optimum viscosity of the flame-resistant adhesive is stabilized, and there is no influence of the working environment temperature at all, and there is sufficient time to manufacture plywood. In addition, the workability was ensured and the mass production was possible. Also, as a curing catalyst for the adhesive for plywood, it is sufficient to add powdery ammonium chloride, which is common and inexpensive,
It is extremely advantageous in terms of cost and has great advantages for the industry.

〔Example〕

 The present invention will be specifically described below with reference to examples.

Example 1 Middle plate of each flameproof adhesive composed of 0.6 mm-thick lauan material as a front plate and 1.3 mm-thick lauan material as a middle plate, and having the component amounts shown in Table 1 below. 300 g per 1 square meter of rice was applied on both sides, and the above-mentioned front plate was superposed on and below it to produce a flameproof plywood under the adhesion conditions shown in Table 1 below.

Table 1 shows the performance test results of the 2.5 mm flameproof plywood thus manufactured.

Example 2 A 0.6 mm-thick lauan material was used as a front plate and a 1.3-mm-thick lauan material was used as a middle plate, and each flame-proof adhesive composed of the component amounts shown in Table 2 below was used as a middle plate. 300 g per 1 square meter of rice was applied on both sides, and the above-mentioned front plate was superposed on and below it to produce a flameproof plywood under the adhesion conditions shown in Table 2 below.

The performance test results of the 2.5 mm flameproof plywood thus manufactured are shown in Table 2.

Claims (4)

[Claims] 1. Urea resin or urea melamine co-condensation resin 50-
80 parts by weight and 20 to 50 parts by weight of the phenol-melamine co-condensation resin (total of 100 parts of both), 5 to 30 parts by weight of an alumina fine particle mixture containing 10 to 60% by weight of melamine and / or melamine isomers. A flameproof plywood characterized in that a flameproof adhesive composed of the above is interposed between the veneer for plywood. 2. The flameproof plywood according to claim 1, wherein the alumina fine particle mixture is a fine powdery recovery catalyst which is a by-product in the urea melamine production process. 3. A urea resin or a urea melamine co-condensation resin 50.
-80 parts by weight and 20-50 parts by weight of phenol-melamine co-condensed resin (total of 100 parts of both), 5-30 parts by weight of alumina fine particle mixture containing 10-60% by weight of melamine and / or melamine isomers. A method for producing a flameproof plywood, characterized by interposing a flameproof adhesive as described above between the veneers for plywood and performing pressure bonding. 4. A cold pressure of 5 to 12 kg / cm ² when a flameproof adhesive is interposed between the veneer for plywood, and then 80 to
The method according to claim 3, wherein plywood is produced by applying a heat pressure of 6 to 13 kg / cm ² under a temperature condition of 120 ° C.