JPS645522B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing plywood having antiseptic properties. More specifically, iodine or iodine and at least one of an aluminum salt of N-nitroso-N-cyclohexylhydroxylamine (hereinafter referred to as NCH Al), a trialkyltin compound, or a triaryltin compound is mixed into the adhesive. The present invention relates to a method of manufacturing plywood having antiseptic properties by manufacturing plywood using a conventional method. In recent years, as the demand for wood in Japan has increased rapidly, resources have decreased and there are concerns that they will be depleted, and foreign trees that have not been used much in the past, such as South Sea wood and African wood, are being imported and used. It is. By the way, recently, in order to solve the housing shortage, streamlined construction methods aiming at lower costs have been introduced and widely used, such as prefabricated construction methods that increase factory production rates, and two-by-four construction methods that have high work efficiency. With the advent of these new construction methods, the demand for plywood is increasing. These plywoods are mainly made of South Sea wood, which has not been used much in the past. Many have drawbacks such as being susceptible to insects. This drawback is a very troubling problem for plywood in general, and for structural plywood in particular, and must be solved urgently. In fact, recently there has been damage such as rotting plywood and damage caused by wood beetles. Therefore, in order to improve the durability of the house, it is necessary to prevent the plywood from rotting,
Insect control treatment is essential. In order to impart antiseptic and insect repellent properties to plywood, it is necessary to perform these chemical treatments, and methods include: (1) impregnating the veneer with chemicals and then gluing them together to create plywood; 2) A method in which a chemical is infiltrated into the finished plywood; or (3) a method in which a chemical is mixed into an adhesive to create plywood.
However, method (1) requires processing and drying equipment, workers, and time in addition to the existing plywood manufacturing equipment;
In method (2), the manufacturing cost is high; the drug must be injected under pressure;
Method (3) is undesirable because it requires drying equipment, workers, and time, which increases costs and leaves negative effects such as deformation and reduced strength of the plywood.Method (3) can be implemented as is without changing the plywood manufacturing process, and the manufacturing cost is reduced. This is the most desirable method as it requires only chemical costs, but compared to methods (1) and (2), it is difficult for the chemicals to fully penetrate into the wood, and therefore the antiseptic and insect repellent effects cannot be fully demonstrated, and the adhesive strength is poor. There are drawbacks such as having a negative impact on The present inventors have found that with method (3), that is, a method in which a preservative is mixed into the adhesive, the drug sufficiently penetrates into the wood and exhibits a preservative effect without substantially reducing adhesive strength. As a result of various studies on pharmaceutical compositions, we added iodine as an active ingredient, or iodine and one or more of NCH/Al, trialkyltin compounds, or triaryltin compounds to an adhesive, and produced plywood using a conventional method. In this case, the present invention was completed based on the new finding that plywood with excellent antiseptic properties can be obtained. The trialkyltin compound or triaryltin compound used in the present invention includes bistributyltin oxide, tributyltin laurate, tributyltin palmitate, tributyltin stearate, tributyltin oleate, tributyltin phthalate, tributyltin sulfamate, bistrimethyl tin oxide, bistriethyltin oxide,
Examples include, but are not limited to, bistripropyltin oxide and triphenyltin hydroxide. These organotin compounds, which have traditionally been used as wood preservatives, are combined with iodine and added to the adhesive.
When plywood is made using a conventional method, the chemical agent has excellent permeability into the wood, and a far superior antiseptic effect can be exhibited without reducing adhesive strength. The mixing ratio of the drugs used in the present invention can be varied at any desired ratio. As a method for adding the agent of the present invention to an adhesive,
It may be added after being dissolved in a solvent, or it may be linearly added to the adhesive as it is and mixed. Also,
It is also possible to incorporate iodine into the molecule of a carrier such as β-cyclodextrin, and add and mix it in the form of an iodine-β-cyclodextrin clathrate. As adhesives, adhesives that condense with formaldehyde are used, such as phenol/formalin resin, melamine/formalin resin, urea/formalin resin, urea/melamine/formalin resin, and resorcinol/formalin resin.
Add and mix 0.5 to 50 parts of the composition of the present invention to 100 parts, and apply adhesive - lamination - cold pressing - according to a conventional method.
If plywood is made by standing-heat-pressing, it will be possible to produce plywood with excellent antiseptic properties in which the chemicals have sufficiently penetrated into the wood without reducing adhesive strength. Furthermore, there is no problem in mixing other preservatives, fungicides, insect repellents, penetrants, etc., and it is not only a preservative but also an anti-mold,
It also enhances the insect repellent effect. Next, the effects of the present invention will be explained with reference to Examples. In addition, all numbers indicating proportions in the examples are parts by weight. Example 1 The chemicals listed in Table 1 were added to and mixed with 100 parts of phenol-formalin resin and 5 parts of wheat flour, and applied to a lauan veneer at a rate of 35 g per square meter (both sides).
5-ply plywood with a thickness of 1.5-3-3-3-1.5 m/m was cold pressed at 10 kg/ ^cm2 for 10 minutes, hot pressed at 140°C,
It was produced under a pressure of 10 Kg/cm ² and a heat-pressing time of 9 minutes. The adhesive strength and wood breakage rate of the intermediate 2nd, 3rd, and 4th layers of this plywood were measured, and the results are shown in Table 1. Furthermore, this plywood was cut into test pieces of 3 x 3 cm, and a preservative test was conducted in accordance with the "Testing Method for Preservative Efficacy of Wood Preservatives" stipulated in JIS-A-9302. The test bacteria used were two types of wood-decaying fungi, Ophthalmia nigra and C. versicolor, which were cultured in a sea sand culture medium. Place the test piece on the test bacteria at a temperature of 26±
It was left to rot for 90 days at 2°C and a relative humidity of 70% or higher. After decay, the test specimen was taken out, mycelia and other deposits on the surface were removed, dried, and weighed to determine the weight loss rate and efficacy was determined by comparison with the untreated test specimen. The results are shown in Table 1.

[Table] Example 2 The drugs listed in Table 2 were added and mixed to 100 parts of urea/melamine/formalin resin, 12 parts of wheat flour, 10 parts of water, and 0.6 parts of ammonium chloride, and 35 g per square meter was mixed.
Apply to lauan veneer (both sides) at a rate of 1.5
-3-3-3-1.5m/m configuration, 5 ply plywood with cold pressure 10Kg/ ^cm2 for 10 minutes, hot pressure temperature 120℃, pressure 10
Kg/cm ² , and the heat-pressing time was 10 minutes. Using this plywood, the adhesive strength and wood breakage rate of the three middle layers were measured in the same manner as in Example 1. moreover,
A preservative efficacy test was conducted. These results are shown in Table 2.

【table】

[Table] As shown in the examples above, iodine, which is the pharmaceutical composition of the present invention, or an aluminum salt of N-nitroso-N-cyclohexylhydroxylamine or one or more of the above-mentioned organotin compounds is added to the adhesive. However, it is clear that by producing plywood using a conventional method, the chemical agent can sufficiently penetrate into the wood without reducing adhesive strength, and plywood with excellent antiseptic properties can be produced.

Claims (1)

[Claims] 1. Bonding the veneer with an adhesive that condenses with formaldehyde mixed with iodine or one or more of aluminum salts of N-nitroso-N-cyclohexylhydroxylamine, trialkyltin compounds, or triaryltin compounds. A unique method of manufacturing preservative-treated plywood.