JPH0272902A - Noncombustible ligneous material - Google Patents

Abstract

PURPOSE:To obtain a noncombustible ligneous material which is superior in adhesive capacity and does not spoil ligneous feeling, by a method wherein an impregnated lumber veneer obtained by impregnating the same with an aqueous solution of a flame retarder consisting effectively of a specific reactant and an untreated ligneous material are stuck to each other. CONSTITUTION:An impregnated lumber veneer obtained by impregnating a lumber veneer of 2-8mm thick with an aqueous solution of a flame retarder consisting effectively of a reactant of alkali salt of phosphoric acid or polyphosphoric acid, or formaldehyde or dicyanodiamide and an untreated ligneous material are stuck to each other. After either the formaldehyde or dicyanodiamide reacts or the phosphoric acid or the polyphosphoric acid reacts on the dicyanodiamide after the phosphoric acid or the polyphosphoric acid is caused to react on an alkaline substance, the above-mentioned reactant is prepared through reaction of the formaldehyde or the alkaline substance. Thus the polyphosphoric acid whose content of P2O5 exceeds 67.4wt.% and less than 88.8wt.% is preferable as the polyphosphoric acid. A urea resin-vinyl acetate resin series or melamine resin-vinyl acetate resin series adhesive agent can be used to stick a dried veneer and ligneous material together.

Description

Detailed Description of the Invention "Field of Industrial Use" The present invention relates to wood materials with flame retardant properties, and particularly to wood materials that are used as building materials such as ceilings, walls, columns, and floors of houses, furniture, and fittings. Regarding the nature of wood materials.

"Prior Art" Flame-retardant wood materials impregnated with flame retardants such as ammonium phosphate and guanidine phosphate have been known.

However, wood materials impregnated with an aqueous ammonium phosphate solution and dried have excellent flame retardant properties, but coarse crystals precipitate on the surface, giving it a rough feel and causing efflorescence, a phenomenon known as powdering. The wood grain becomes dull and the wood texture is noticeably impaired. Furthermore, due to the formation of efflorescence, the adhesion performance with other wood materials is poor.

When wood materials are impregnated with an aqueous solution of guanidine phosphate and dried, guanidine phosphate is water-soluble and has no reactivity, so it easily oozes out on contact with water or moisture, making the surface of the wood material sticky. It also has the disadvantage that it easily leaks out, reducing flame retardant performance, and that it seeps out and is highly hygroscopic, reducing adhesive performance with other wood materials.

``Problems to be Solved by the Invention'' In view of the above circumstances, the present invention provides excellent adhesive performance when laminating a wood veneer impregnated with a flame retardant and an untreated wood material.
The aim is to provide a flame-retardant wood material that does not impair the wood texture.

``Means for Solving the Problems J'' The present inventors first impregnated various wood materials with an aqueous flame retardant solution containing an alkali salt of phosphoric acid or polyphosphoric acid, formaldehyde, and a dicyandiamide reactant as active ingredients, and then dried the materials. We have found that it is possible to obtain a flame-retardant wood material that has resistance to water, does not impair the wood texture, and passes grade 3 of flame retardancy according to JIS A-1321.
If you impregnate a 1m wood veneer with the above flame retardant aqueous solution, and after drying, use adhesive to laminate it to untreated wood material, it will be a good flame retardant without damaging the wood texture. They discovered that a wood material with excellent flame retardancy can be obtained, and arrived at the present invention.

That is, the present invention relates to an impregnated wood veneer in which a wood veneer with a thickness of 2 to 8 mm is impregnated with an aqueous flame retardant solution containing a reaction product of an alkali salt of phosphoric acid or polyphosphoric acid, formaldehyde, and dicyandiamide as an active ingredient, and an untreated wood veneer. It is a flame-retardant wood material made by bonding other materials.

The wood species of the impregnated wood veneer and untreated wood material used in the present invention include, for example, coniferous trees such as cedar, red pine, larch, cypress, toga, hihaheihi, Japanese pine, Japanese hemlock, Japanese spruce, Japanese fir, Japanese cedar, etc. , Macamba beech, Japanese maple, oak, Quercus oak, Katsura, Sakushi, Zelkova, Shiitsuki, Kiri, Shinatsuki, Japanese elm, Lauan,
Hardwoods such as avitone, teak, and rosewood can be used. In addition, the shape and structure of the untreated wood material to be laminated with the impregnated wood veneer include sawn timber such as veneer, square lumber, and board, processed wood such as plywood and laminated wood, particle mate, and Phino 4-y. %”-code etc. can also be used.

The reaction product of phosphoric acid or polyphosphoric acid alkali salt, formaldehyde and dicyandiamide, which is the active ingredient of the present invention, can be obtained by reacting phosphoric acid or polyphosphoric acid with an alkaline substance and then reacting formaldehyde or dicyandiamide, or It is created by reacting phosphoric acid with dicyandiamide, followed by formaldehyde and an alkaline substance.

Here, the polyphosphoric acid preferably has a P2O5 content of more than 67.4% by weight and less than 88.8% by weight.

Further, as the alkaline substance, ammonia, hydrazine, hydroxylamine, lower alkylamine, lower alkanolamine, guanidine, lower alkylguanidine, guanylurea, polyalkylene polyamine, caustic potash, etc. can be used.

The reaction ratio of phosphoric acid or polyphosphoric acid, dicyandiamide, formaldehyde and alkaline substance is 0.2 to 3 dicyandiamide per mole of phosphorus #IR or glyphosphoric acid.
The ratio of formaldehyde is preferably 0.2 to 4 mol, and the alkaline substance is preferably 0.5 to 2 mol per ml.

Known flame retardants such as ammonium phosphate, oxalic acid, ammonium oxalate, silt, ammonium sulfate, sodium sulfate, halodane compounds such as ammonium bromide, and the like can be added to the flame retardant of the present invention. The amount added is O, 1 to 20X based on 100 parts by weight of the solid content of the flame retardant of the present invention.
A lid is preferred.

Furthermore, 7-minoplast resins such as area resins and melamine resins can be added. The addition amount is preferably 1 to 20 parts by weight (solid content) per 100]ii parts of the solid content of the flame retardant of the present invention. Addition of these aminoplast resins can increase durability such as water resistance.

As a method for impregnating a veneer with the flame retardant aqueous solution of the present invention, known vacuum injection methods, pressurized injection methods, and reduced pressure pressurized injection methods can be used.

The veneer impregnated with the flame retardant aqueous solution of the present invention is dried naturally, and then using drying equipment, it is heated by steam, hot air, high frequency, etc., or vacuum heated.

Area resin-vinyl acetate resin is also used as an adhesive for bonding a wood material to a veneer that has been impregnated with an aqueous flame retardant solution containing a reaction product of phosphoric acid or an alkali salt of phosphoric acid, formaldehyde, and dicyandiamide and dried. system,
Melamine resin-vinyl acetate resin systems, aqueous vinyl urethane resin systems, urethane resin systems, acrylic resin systems, resorcinol resin threads, synthetic leather rubber systems, rubber adhesives, etc. can be used.

These adhesives are applied to wood veneers coated with an aqueous flame retardant solution, untreated wood materials, or both, by methods such as brushing or roll coating.

The flame retardant-impregnated wood veneer is laminated to at least one untreated wood material via an adhesive under cold or hot pressure.

An untreated wood material is laminated with an adhesive to an impregnated wood veneer obtained by impregnating with a flame retardant containing a reaction product of phosphoric acid or polyphosphoric acid alkali salt, formaldehyde, and dicyandiamide as active ingredients and drying it according to the present invention. The flame-retardant wood material does not dull the wood grain or impair the wood feel, and even though the wood material is laminated without flame-retardant treatment, it is JIS A- compliant on the impregnated wood veneer surface. It has the performance to pass grade 3 flame retardancy according to the 1321 method.

Incidentally, a flame retardant containing a reaction product of phosphoric acid or an alkali salt of polyphosphoric acid, formaldehyde, and dicyanamide as an active ingredient is particularly excellent in impregnating wood veneer, and can be easily impregnated by a known injection method. Even with wood that is difficult to impregnate, such as Japanese larch, a wood veneer with a thickness of 2 to 8 mm can be used for 600 m.
After 30 minutes of decompression treatment at rxHg, the pressure was 15 ky/
cyt" for 15 to 30 minutes.In addition, for sapwood of cypress and cedar, etc., immerse it in the flame retardant water bath solution for 30 minutes under a reduced pressure of 600N+Hg. You can obtain a wood veneer with a lid simply by keeping it impregnated.

The predetermined impregnated lid here means that the flame retardant impregnation f (solid content) per 1000 wood veneer lids is usually 5 to 150 parts by weight, preferably 15 to 100 parts by weight. If the amount of impregnation is less than 5 parts by weight, the wood texture can be maintained, but the flame retardant performance is insufficient and it will not pass the grade 3 flame retardant, and if it is more than 1503 (i part), it will pass the grade 3 flame retardant. However, since the wood is hard, it tends to break when nailed, making it impractical.

Further, the flame-retardant wood material of the present invention can be easily made by laminating the above-mentioned ant retardant-impregnated wood veneer with an untreated wood material using a known adhesive and a known method.
It also has excellent adhesion performance as determined by the embossment test method of ASTM D 2339-70, and is highly practical.

"Example" Next, the present invention will be further explained by reference examples, examples, and comparative examples. Incidentally, the combustion test was conducted according to the flame retardant class 3 test method of JIS A-1321.

Reference Example 1 A four-bottle flask equipped with a thermometer and a cooling tube was charged with 89% by weight phosphoric acid 330y and water 1001g and heated to 70°C.

Next, dicyandiamide 252I was added and reacted at 100°C for 1 hour. Then 25% by weight ammonia water 224I
After neutralization by adding 37Mk% formalin 486J
1 and reacted at 70°C for 3 hours. This was diluted with water to obtain a transparent aqueous flame retardant solution with a concentration of 50% by weight.

ε Example 2 Put 136 y of 25 wt% ammonia water into a four-roof flask equipped with a thermometer, cooling tube, and dropping funnel, and add 186 y of polyphosphoric acid (P205 content 76 wt %) dropwise at 30°C or below to add ammonium polyphosphate. Synthesized. Next, 37% by weight formalin 162.2F was added, the temperature was raised to 70°C, and after holding at this temperature for 1 hour, dicyandiamide 168.
2. F was added and reacted at 70°C for 2 hours. This was diluted with water to obtain a transparent ammonium polyphosphate, formaldehyde, and dicyandiamide reactant water bath solution having a concentration of 40%.

Reference Example 3 238 25% by weight ammonia water in a four-loop flask equipped with a thermometer, cooling tube, and dropping funnel! Polyphosphoric acid (P205 content 76% by weight) 1861t-
The mixture was added dropwise to synthesize ammonium polyphosphate. Next 1c37
Weight % formalin 81. ．． ll1t- was added, the temperature was raised to 70°C, and after holding at this temperature for 1 hour, 84.1 II″ft of dicyandiamide was added and reacted at 70°C for 2 hours. This was diluted with water to give a concentration of 45% by weight. A transparent aqueous solution of ammonium polyphosphate, formaldehyde, and dicyandiamide reactants was obtained.

Example 1 An impregnation container equipped with a pressure reduction device had a length of 40 crrL and a width of 2
2 crIL, 6 parrot thick cypress veneer for 5 shepherds. Next, the flame retardant aqueous solution of Reference Example 1 was diluted with water to make a 35% by weight aqueous solution, and the treatment liquid was put into the impregnating container and the board was completely immersed. Next, operate the decompression device to reduce the pressure inside the impregnation container to 6
The pressure was reduced to 0 mHH and maintained for 30 minutes. Next, the pressure was returned to normal and held for 30 minutes, and then the treated wood was taken out and the treatment liquid on the surface was thoroughly wiped off.

Next, it was air-dried at room temperature for one day, and then dried with hot air at 40°C for one day and at 80°C for 30 minutes to obtain a flame-retardant wood veneer with an appearance similar to that of untreated wood. Next, the length of 5 pieces is 4
0 cm, width 22 cm, and thickness 10 mm of untreated rice hemlock, resorcinol-based resin Plyophen 60 was applied to each.
00 (Dainippon Ink & Chemicals Co., Ltd. M product) and 100 parts by weight of a catalyst) TD-473 (Dainippon Ink & Chemicals Co., Ltd. M product) 15 parts by weight of an adhesive prepared by mixing 2
5,017 m'' was coated, and each flame retardant wood veneer was placed on top of it and pressed under a pressure of 10 Kli 7 cm'' at room temperature for 16 hours. After 16 hours, the pressure was decompressed to obtain five pieces of flame-retardant wood that had the same appearance as untreated wood. A 18 cm x 22 cm area from the end of each flame-retardant wood obtained was subjected to a shear tensile test according to the ASTM D-2339-70 method to examine adhesive performance, and the remaining area was subjected to a combustion test, and the results are listed. Shown in 1.

Comparative Example 1 A flame-retardant wood veneer was obtained in the same manner as in Example 1 except that commercially available ammonium phosphate was used as a flame retardant. Crystals were deposited on the surface of each wood veneer, and efflorescence was observed. Five pieces of flame-retardant wood were obtained in the same manner as in Example 1 using five treated wood veneers, and a shear tensile test and a combustion test were conducted. The results are shown in Table 1.

Example 2 Five oak veneers measuring 402 cm in length, 22 cm in width, and 2 cm in thickness were placed in an impregnating container equipped with a pressure reducing device and a pressurizing device. A treatment solution obtained by diluting the flame retardant aqueous solution of Reference Example 2 with water to obtain a 36-fold i4 aqueous solution was placed in a container and the veneer was completely immersed. Next, operate the decompression device to reduce the pressure inside the immersion container to 50 degrees.
The pressure was reduced to 171 Hg and maintained for 30 minutes. Next, after returning to normal pressure, the pressurizing device was operated to increase the pressure to 181 v/crrL'' and maintain it for 30 minutes.

After returning to normal pressure and taking out the treated wood veneer, wiping off the treatment liquid on the surface, it was air-dried at room temperature for 2 days, and then dried at 40℃ for 1 hour.
The wood veneer was heat-dried for 2 hours at 80° C. for 2 hours to obtain a flame-retardant wood veneer with an appearance similar to that of untreated wood.

Next, the length of 5 pieces is 40c! IL, 22cIrL width, 10n thickness untreated rice hemlock, each with urea resin Primamine TD-2924 (Dainippon Ink & Chemicals ■ product) 80 771 parts by weight, vinyl acetate emulsion Noyon Bonco) W-2530 (Dainippon Ink Chemical Industry ■Product)
An adhesive prepared by mixing 20 parts by weight of flour, 10 parts by weight of wheat flour, 10 parts by weight of water, and 5 parts by weight of a wounded ammonium chloride aqueous solution was applied at 260 g/m'', and a flame-retardant wood veneer was applied on top of the adhesive. 110℃, 15 kg/cm”
It was pressed for 8 minutes. After depressurization and cooling, a flame-retardant wood with an appearance no different from untreated wood was obtained. A shear tensile test was performed on a portion of 187y x 22clrL from the end of each flame-retardant wood obtained according to the ASTM D-2339-70 method, and a combustion test was performed on the remaining portion, and the results are shown in Table 2.

Comparative Example 2 A flame-retardant wood veneer was obtained in the same manner as in Example 2, except that commercially available ammonium phosphate was used as the flame retardant. Crystals were precipitated on the surface of each veneer, and sunlight was observed. Five treated wood veneers were replaced with five untreated rice hemlock veneers in the same manner as in Example 2.
A shear tensile test and a combustion test were conducted on each flame-retardant wood obtained. The results are shown in Table 2.

Example 3 An impregnating container equipped with a pressure reducing device and a pressurizing device has a length of 40 mm and an I
[223, 5 shepherds of steamed larch veneer 5m thick were made. Next, dilute the flame retardant aqueous solution of Reference Example 3 with water and
A treatment solution made into a 5 weight aqueous solution was placed in a container and the veneer was completely immersed. Next, the pressure reduction device was operated to reduce the pressure inside the impregnation container to a degree of vacuum of 60+mHg, which was maintained for 40 minutes. Next, after returning to normal pressure, operate the pressurization device to increase the pressure to 15 kg.
/cm" and maintained for 30 minutes. After returning to normal pressure, the treated wood veneer was taken out, and the treated wood veneer was wiped off from the surface, then air-dried at room temperature for 2 days, and then heated at 40°C for 1 day. 80℃
By heating and drying the wood for 5 hours, a wood veneer was obtained that had the same laminar flammability as untreated wood.

Next, the water-based vinyl urethane resin DIC BOND V-505 (Dainippon Ink & Chemicals Co., Ltd. product) was applied to both sides of 5 untreated boards of steamed larch, 22α in length, 40CTL in width, and 6 plates in thickness. A piece of adhesive prepared by mixing 100 parts by weight with 15 parts by weight of a hardening agent Dickbon l'M-3 (product of Dainippon Ink & Chemicals) was used to make a piece of Ufi1501/m2.
40cm in length, 22cm in width, and 22cm in thickness with flame-retardant wood veneer on one side and steamed on the other side.
5 m long larch boards were stacked in the same manner as the 3 mm plywood and pressed together at room temperature under a pressure of 10 kg/α2 for 16 hours. After depressurization, a flame-retardant wood with an appearance no different from untreated wood was obtained. 18 from the end of each flame retardant wood obtained
ASTM D-23 for cnLX22cm part
A shear tensile test was conducted using the 39-70 method, and a combustion test was conducted on the remaining portion, and the results are shown in Table 3.

Comparative Example 3 A flame-retardant wood veneer was obtained in the same manner as in Example 3, except that commercially available guanidine phosphate was used as the flame retardant. The surface of each veneer remained damp even after drying, and felt sticky on rainy days. Five treated wood veneers were adhered to each of five untreated larch boards in the same manner as in Example 3, and a shear tensile test and a phosphorous burning test were conducted on each of the resulting flame-retardant woods.Results are shown in Table 3.

/ / / / / / / / / / Evaluation of each test result in Table 1 was based on the following criteria.

The flame retardant test was conducted on a wood veneer impregnated with a flame retardant7.
'L7'C, and the following evaluation criteria are the same for other tables.

Tc: Pass when the exhaust temperature curve exceeds the standard temperature curve for 3 minutes or more during the heating test T-dθ; The exhaust flow rate curve and the standard temperature curve in the part where the exhaust temperature curve exceeds the standard temperature curve The area of the enclosed part (°C/min), 350 or less is a passing CA; the smoke emission coefficient per unit time, 120 or less is a passing afterflame time; there must be no afterflame for 30 seconds or more after the end of heating; backside cracking; significant deformation No cracks with a thickness of 1710 or more An untreated wood material is bonded to the back side of a thin flame-retardant wood veneer obtained by impregnating and drying an aqueous flame retardant solution containing an alkali salt of phosphoric acid or haphophosphoric acid, formaldehyde, and a dicyandiamide reaction product as active ingredients. Even though it is only bonded with an adhesive, the veneer has the excellent effect of passing grade 3 flame retardancy in JIS A-1321.

In addition, the flame retardant wood material of the present invention has good impregnability with the flame retardant used in the present invention, and the thickness of the veneer impregnated with the flame retardant is as thin as 2 to 8 wg, so even wood that is difficult to impregnate is difficult to impregnate. It is possible to sufficiently impregnate the flame retardant, and the amount of flame retardant can be reduced because only the surface veneer is impregnated, and it is also cheaper to impregnate the entire wood material, making it extremely practical. It is rich in sexuality.

Agent Patent Attorney Katsutoshi Takahashi

Claims (1)

[Claims] It is made by adhering an impregnated wood veneer with an aqueous flame retardant solution containing a reaction product of phosphoric acid or polyphosphoric acid alkali salt, formaldehyde, and dicyanryamide as active ingredients to an untreated wood material. Flame retardant wood material.