JPS61271366A - Waterproof emulsion adhesive - Google Patents

Abstract

PURPOSE:To improve initial bond performance, waterproofing bond performance and shelf stability, by blending a previously emulsified amino resin and an org. amine and/or a basic salt with a resin emulsion mainly composed of vinyl acetate and adjusting the pH to a value within a specified range. CONSTITUTION:A previously emulsified amino resin is mixed with a resin emulsion mainly composed of vinyl acetate. An org. amine and/or a basic salt are/is blended with the mixture to adjust the ph to 7.0 or above, thus obtaining the titled adhesive. The pH of the mixture is adjusted by the org. amine in place of conventional alkaline substance (e.g., NaOH) to thereby improve shelf stability. Examples of the org. amines are ethylenediamine and diethylenetriamine. Examples of the basic salts are sodium carbonate, ammonium carbonate, disodium hydrogen-phosphate and sodium phosphate.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a water-resistant resin emulsion mainly composed of vinyl acetate, and contains 1% of an emulsion seal suitable for bonding wood, paper, etc. It is in the interest of providing.

[Conventional technology]

Conventionally, vinyl acetate resin emulsion carbon has been widely used as an adhesive for wood, paper, etc. because it has excellent characteristics such as good adhesive strength development (initial adhesion) and ease of use. However, they have drawbacks such as poor water resistance, and to compensate for these drawbacks, it is common practice to mix and use amino resin liquid adhesives such as area resins and melamine resins.

[Problem that the invention seeks to solve]

However, such a method requires a lot of work for preparing the size liquid and the size, and the excellent initial adhesion performance required by the characteristics of the vinyl acetate resin resin Maruji M is achieved by mixing the amino resin liquid adhesive T-. During the process of lowering the

[Means and actions to solve the problem]

In order to solve these problems, the inventors of the present invention have conducted extensive research and have developed an emulsion bottle of vinyl acetate resin by emulsifying amino resins such as urea resin and Melacin resin in advance. By mixing, the water-resistant adhesion performance, which is a drawback of vinyl acetate resin emulsions, can be improved without reducing the initial adhesion performance.Moreover, interestingly, it is possible to improve the water-resistant adhesion performance, which is a drawback of vinyl acetate resin emulsions. Organic amine and/or
Or add a basic salt t- to adjust the Pkl of the mixture to 7. lJ
By carrying out the above steps, a mixture of amino thread resin emulsion to vinyl acetate resin emulsion can be obtained without separation regardless of the mixing ratio, and has excellent storage stability. He discovered that the mixed liquid could withstand long-term storage, and completed the invention.

That is, in the present invention, a resin pore suspension containing acetic acid and di-A- is pre-emulsionized with a nine-amino resin,
By blending an organic amine and/f or a basic salt, PHt
This is a water-resistant emulsion adhesive with an IA rating of -7.0 or higher.

Adding aguno-based resin water study fluid to vinyl acetate resin emulsion.
Even if the pn of the mixed liquid is adjusted to #I4 to be 10 or more when the mixture is mixed, if the mixing ratio of the anno-resin water mortar is as low as 5 Ω% or less, separation will occur during storage.

On the other hand, the amino resin resin used in the present invention can be mixed in any ratio, and this difference is a new finding that cannot be predicted.

In addition, if a normal alkaline substance such as caustic soda is used to make the mixed solution put-7.0 or higher, the PH will be affected by the acid liberated from the vinyl acetate resin.
quickly decreases, resulting in decreased storage stability. However, if an alkaline substance is used when an organic amine and/or a basic salt is used, it becomes possible to suppress changes in the pH of the mixture over time.

Examples of the organic azole herein include ethylenecyane, diethyltriabane, hextemethylenetetraban, triethanolamine, and ammonia. Further, basic salts include potassium carbonate, sodium sulfate, ammonium dibasic acid, dibasic and triphosphate, and the like.

It is a resin made by reacting formaldehyde with one or more selected from the group consisting of seven togeanain, benzoguanami, etc., and depending on these, phenol, resorcinol, yvyl, def/phosphorus, The effect of the present invention remains unchanged even when one or more woodcutter selected from alkylresorcinol, xylenol, baratoluene sulfonide, acetone, methyl ethyl lactone, cyclohexteno7, etc. are co-condensed.

Mana, vinyl acetate resin emulsion is a homopoly! - as well as vinyl acetate and acrylic acid and its derivatives, methacrylic eIR and its derivatives, ethylene,
Vinyl chloride, vinylidene chloride, malein! ! , N-methylol acrylamide, allyl alcohol, allyl glycidyl ether, allyl aldehyde, crotonic acid, and copolymerizable materials such as is used.

〔Effect of the invention〕

The adhesive obtained by the method of the present invention has initial adhesion performance,
Due to its excellent water-resistant adhesion performance and storage stability, it is suitable for adhering printed paper and decorative veneer to plywood, and is suitable for adhesion of wall panels, flush panels, laminated wood, finger sillboard, furniture assembly, etc., and paperboard. It is also suitable for adhering paper tubes, cardboard, etc.

〔Example〕

The present invention will be explained in detail below by way of examples.

Example 1 37% tIk degree formalin 210? , Urea 50? , put a lid on melamine 481 in a 500-capacity Mitsuro flask, add 71 g to 5th phosphate powder 1, and adjust the pH to 9.6.
The temperature was raised to 90°C while stirring. After reacting at 90°C for 50 minutes, 20% formic acid water bath liquid gold was added to adjust the pH of the reaction solution to 5.0, and the condensation reaction was continued. When the reaction solution is cooled to 20°C and becomes cloudy, add a third phosphorus agent to bring the PHt of the reaction solution to -9.0.At the same time, 1ltlI of the reaction solution is
Cooled to 0°C. Next, acetone 10? and polyvinyl alcohol (Chidari Rare ◆205) Lot and nonionic surfactant (Lion KKIa, +) Bo, t
tyx) 0.7ftm1.React for 20 minutes
The temperature was raised to 0° C., and the mixture was reacted for another 30 minutes, and when the emulsion was complete, 6th phosphate was added to adjust the pH to 7.5, and the mixture was cooled.

The thus obtained Azuno m finger emulsion W/ and the commercially available stationary vinyl resin emulsion w y (Hounen oil pot good: vw-
415) in various ratios.

Add triethanolamine to these mixed resins and adjust the pH.
#I4 was plated on t-a5 to obtain a water-resistant emulsion adhesive of the present invention.

In order to clarify the properties of this adhesive,
Storage stability was investigated by storing in a constant temperature chamber maintained at 0° C. and measuring changes in viscosity over time.

Well, 100 parts by weight of this adhesive contains 53% paratoluene sulfone #! 7 to 1% [t-6m violet] to prepare a paste solution T-, then apply it to both sides of a lauan veneer with a thickness of 2.0~ at a ratio of 5509/1rl (both sides) to the same thickness. The lauan veneers were stacked one on top of the other so that their fiber directions were perpendicular to each other, and a pressure of 8 m/- was applied for 1 hour.

After that, it was left for one week and then tested according to the JAS General Compatibility Board Class 2 Test Method #)I! The firmness was measured. Avoid the same mff1
Jl length 2.5X, 1m 25%, length 75%'
) On one side of the lauan plywood, add 160mm to the 25x length part.
/A, and lauan plywood of the same shape was stacked so as to overlap 25% of the length, and pressed together with a pressure of 10 kg/-.

The test piece thus obtained was taken out at predetermined time intervals at room temperature, and the tensile adhesive strength was immediately measured to examine adhesive strength development.

Control M 1゜In place of the 9Azuno resin emulsion used in the F11 test, a commercially available area resin adhesive (Honen Oil Press 217W-0) was used.
A control adhesive was obtained in the same manner as in Example 1 except that 62) was used.◎ This adhesive was examined for storage stability, water resistant adhesion, and N contact strength development in the same manner as in Actual Example 1. Ta.

These test results 2 of Example 1 and Control Example 1 and vinyl acetate resin emulsion (Honen Oil KKm: vw-415)
The following table shows the comparison of the test results for the following cases using only one of these.

Formalin 120C1 at 37% concentration, urea 2502, Melan 400F, water 4502, h-? Thimethylenetetrain 2f and water-bathable copolymer of acrylamide and acrylic acid 502 were placed in a Mitsuro flask and heated to 80° C. with stirring. After reacting at 80°C for 250 minutes, 5ft of 25X caustic solution was added, the mixture was cooled to 50°C, and the azuno resin emulsion was added.

Using this amino resin emulsion, a vinyl acetate resin emulsion (Honen Oil Ic
(manufactured by K: VW-415), and then @3 Rinbanda was added to the mixed mixture to make the pH 7.5, m! iL
, a water-resistant emulsion adhesive of the present invention was obtained.

In order to clarify the characteristics of this adhesive, we will use 71! ii
In the same way as Meat 1, storage stability, water resistance and adhesion, and strength development of the membrane layer were examined.

The results are shown in the table below.

The above 5A examples show that the uninvented method has excellent effects.
-It is obvious that it has.

Patent author: Hoenen Oil Co., Ltd.

Claims (1)

[Claims] A water-resistant emulsion adhesive prepared by blending a pre-emulsified amino resin with an organic amine and/or a basic salt into a resin emulsion containing vinyl acetate as a main component, and adjusting the pH to 7.0 or higher.