JPS5834883A - Remoistening adhesive structure - Google Patents

Abstract

PURPOSE:The titled structure with excellent strength suitable for connecting and repairing veneers and exhibiting sufficient adhesive force, which is prepd. by laminating a water-sol. polymer film and a polymer film having a lowest dissolution temp. higher than that of the former film. CONSTITUTION:A polymer film (A) such as a polyvinyl alcohol film sol. both in cold and hot water, and a polymer film (B) such as a polyvinyl alcohol film having a lowest dissolution temp. >=30 deg.C which is at least 10 deg.C higher than that of the film A are laminated to form a remoistening adhesive structure 1 in the form of a tape, film, sheet or label. When veneers 2 and 2 are moistened and connected to each other by sticking said structures 1 and 1 and laminated by using other veneers 3 and 3' and a thermosetting resin adhesive, the structures disappear by being incorporated in said adhesive, to obtain a decorative laminate or plywood without failure in adhesion or unevenness in thickness. EFFECT:The structure is capable of being wound without blocking.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides structures such as tapes, films, sheets, etc. that have rewet adhesive properties.

Traditionally, Kukut paper re-aming tape and Kukut paper adhesive tape have been used as veneer connection tapes and veneer repair tapes. When trying to manufacture a decorative plywood board using a curable resin as an adhesive, the area where the tape was attached swelled by the thickness of the kraft paper compared to other areas, making it impossible to obtain a product with uniform thickness.) However, there were problems such as the adhesive strength at the location where the tape was attached was weaker than at other locations.

The present invention solves these problems.

As shown in the cross-sectional view in FIG. 1, the rewetting adhesive structure of the present invention is a polymeric film (4
) and the minimum melting temperature is 50℃ or higher than that of the shiny one.
It has a structure in which a high-polymer film (8) is laminated with a temperature higher than .degree.

The rewetting adhesive structure of the present invention has the following excellent effects.

(1) The structure consisting of (A)/(II) of the present invention can be wound up, without causing blocking.
When a structure comprising (4)/(B) of the present invention, such as tape, is used to connect or repair veneers (when the veneer is damp, see 11. When the veneer is not moist enough) veneer f
! - Moisten (A)/@1 (moisten side A before use)
(Al is dissolved and exhibits sufficient adhesive strength, and the strength of the tape itself is maintained by the film (6) that does not dissolve.

ts+ The strength of the tape is greater than that of Kukuft paper recycle adhesive tape, and the thickness can be reduced by 4° (4°).
) If plywood or decorative board is manufactured by connecting or repairing veneers and then laminating them with other veneers using thermosetting resin and hot pressing them as described in (ii) above, the above tape can be used with thermosetting resin. It fuses and disappears, and does not cause adhesion failure or thickness irregularities.

The polymer film (4) in the present invention is one that is soluble in both cold water and hot water), such as a soluble starch film in a polyvinyl alcohol film. Particularly preferred is a polyvinyl alcohol or modified polyvinyl alcohol film having a minimum melting temperature of less than 50°C, especially less than 20°C. The original of (4) is not particularly limited, but is usually FiIO to 40 voices, preferably 10 to 5011. (A) may be embossed or foamed.

Next, the polymer film in the present invention has a minimum melting temperature of 50°C or more, preferably riSO°C or more, and is higher than that of (4) by 910°C or more, preferably 20°C or more, and is usually polyvinyl alcohol-based. A film is used. There is no limit to the thickness of (2) 441, but it is usually 1j10
~6011, preferably tilO~SOμ in many cases. (2) It may be subjected to durothermal, -axial or biaxial stretching treatment.

The shape M of the laminated structure made of (B) is obtained by RIIing the wheat WJ (film) with water or steam and then forming the film (
4) A method of laminating the film holder and the film @ using a water-methanol mixture, an aqueous inorganic salt solution, a water-soluble glue, etc.
Any method can be used, such as applying and drying a polymer dope of 41IwL.

The shape of the structure made of the material can be a tape, film, sheet, label, etc., but the shape of the tape is particularly important.

The rewet adhesive JII3tIIkJ of the present invention is particularly important as edge tape for veneers, tape for connecting veneers, tape for repairing veneers, and tape for connecting veneers during the manufacture of decorative laminates. It can be used for various purposes.

Next, an example will be given to explain the present invention! The adhesive JI artifact will be further explained.

The minimum melting temperature of the film is 21 beaker KO℃.
Prepare water 21 and fix it with the specified metal fittings.
This is the temperature when no undissolved matter is visible to the naked eye when the film piece (2) is put in and the water bath temperature is raised at a rate of 1 roe under strong stirring using a magnetic star two. , Example 1 (manufacture of plywood) Hot water soluble polyvinyl alcohol film B with a minimum melting temperature of 65 °C (polymerization of polyvinyl aphrecol & 170
After applying water to one side of G, saponification degree 99 mol%, thickness 20 mol%, AA physical product), cold water soluble polyvinyl 1! with a minimum melting temperature of 0 ° C. Recol Film A (Polyvinyl alcohol polymerization degree 1400, saponification degree 88 mol%
, 20 μm thick, embossed product) were stacked and pressed together and dried to produce a laminate film, which was then cut into 20 μm pieces to create a tape.

Divide into two 15a * x 15- size wet friend veneer t,
The split parts were lined up in contact with each other, joined together (11KjI), and the tape was attached in the right angle direction while pressing with the palm of the hand so that it was in contact with the veneer. The veneers joined and connected in this way could be lifted by holding one piece between one's fingers.

Next, a melamine-modified urea resin adhesive was applied to both sides of the above-mentioned bonded and connected veneers as intermediate plates, and the veneers with 15 scratches and 15 oa were stacked one on top of the other. A 3-ply plywood was obtained by cold pressing and then hot pressing.

The situation is shown in Figure t11g2. In Figure 2, IFi tape, 2Fi connected veneer, 3. S' is another veneer.

The thus obtained plywood had no blisters due to the interposition of the tape, and there was no decrease in adhesive strength. Also clamping m
When I broke it down and examined it, I found that the tape had fused with the melamine-modified urea resin adhesive and disappeared, leaving no trace of the tape.

Example 2 (Plywood manufacturing method) Hot water soluble polyvinyl alcohol film B with a minimum melting temperature of 85°C (polymerization degree of polyvinyl alcohol 1700,
A cold water soluble polyvinyl alcohol film with a degree of saponification of 99 mol%, a thickness of 14 tones, a two-wheel stretching amount of 5 times x 3 times) and a minimum dissolution humidity of 10°C (degree of polymerization of polyvinyl alcohol 1).
400 and KEN (TL, 90 mol%, thickness 20 tones, embossed product) were laminated using a 5096 methanol solution of lyticum chloride, and then cut into 20-inch widths to prepare tapes.

Plywood was produced in the same manner as in Example 1 using the tape, but the resulting plywood had no cracks due to the interposition of the tape, and there was no decrease in adhesive strength. When the adhesive amount was destroyed, the tape was fused with the melamine-modified IIIt fat adhesive and a large portion of the adhesive had disappeared.

Example 3 (manufacture of decorative board 8) Arrange six thin veneer boards with a medium width of 10 to 50 m so that they are in contact with each other at 7 points, and apply A1 of the tape made in Example 1 along the joint gK.
Warm it with 1 liter of water, press it with your fingers and stick it on, and use it as a wide plywood board. This was layered on a plywood base material so that the tape adhesion direction was in contact with the plywood, and the decorative board was manufactured by thermocompression bonding via a melamine resin adhesive. In Fig. 3, there are 12ti connected veneer boards and 15tlj apricot board base materials. FIG. 4 shows the back side of the connected plywood boards 12 shown in FIG. 3), and 11 is a tape.

The obtained decorative board had no cracks due to the presence of the tape, and there was no decrease in adhesive strength.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the backing adhesive structure of the present invention, and FIG. 2 is a cross-sectional view showing the backing adhesive structure of the present invention, and FIG. Figure 6 is an explanatory diagram showing the manner in which a decorative board is produced by joining and connecting veneers using rewetting adhesive tape, and Figure 4 is an explanatory diagram showing the manner in which a decorative board is manufactured. It is a sketch when the veneer board in FIG. 3 is viewed from the back side. A, B...Polymer film 1...Tape 2...Connected veneer 5.5'...Other veneer 11...・Tape 12...Connected veneer board 13...Plywood base patent applicant Nichisuego Chemical Industry Co., Ltd.'JJ? )l
Diagram No. 2.1A

Claims (1)

[Claims] 1. A polymer film (2) that is soluble in both cold water and hot water, and a minimum dissolution temperature of 50°C or higher and 10% higher than that of (g).
A rewetting adhesive structure having a laminated structure with polymer 74lum (6) having a temperature higher than ℃. The structure according to claim 4s1, wherein the polymer film (i) is a polyvinyl alcohol film.