JPS60250079A - Adhesive composition - Google Patents

Abstract

PURPOSE:To provide an adhesive compsn. suitable for bonding paper to paper or to cloth, prepd. by dissolving and dispersing polyvinyl acetate emulsion, sodium carboxymethylcellulose and microfibrillated cellulose in water. CONSTITUTION:The adhesive compsn. consists of a viscous liquid obtained by blending (A) polyvinyl acetate emulsion, (B) aqueous soln. of sodium carboxymethylcellulose and (C) aqueous dispersion of microfibrillated cellulose. Solid contents should pref. be about 0.5-5pts. sodium carboxymethylcellulose, about 5-30pts. polyvinyl acetate and about 0.3-4pts. microfibrillated cellulose per 100pts. of the compsn. The adhesive compsn. is esp. suitable as backing material and binder in the preparation of hanging wall picture, hanging scroll, calligraphic scroll, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an adhesive composition used for adhering paper to paper or paper to cloth, and is particularly used in the process of making hanging items, hanging scrolls, scrolls, etc. The present invention relates to an adhesive composition suitable for bonding to a substrate.

The mounting of calligraphy and paintings must endure viewing and preservation for many years, and for this purpose they are manufactured using traditional materials and work processes, but the contribution of adhesives is extremely important. .

The mounting process will be briefly explained using a hanging scroll as an example. First, the materials to be mounted such as calligraphy and paintings, as well as the mounting materials such as cloth and paper, are lined with thin Japanese paper coated with mounting glue as evenly as possible. Once this has air-dried, add some moisture to the backing surface, and while it is in a sufficiently damp state, apply a small amount of glue to the four corners of the back side and board it up (several sheets of washi paper on a base with a pattern of sturdy combinations of thin pieces of wood). Lay them on top of each other to create a flat, ventilated surface. At this time, considering the elasticity of the material, apply appropriate tension to the material, paste it, and let it dry. The above is the preparation process.

Peel off the board using a bamboo tube, cut the prepared mounting object and mounting material into the required shape and size, and paste and connect them together using mounting glue (the attachment is called mawashi). Arrange. The entire surface of this material is lined with thin Japanese paper.

If necessary, line it with more thin Japanese paper. At this time, it is desirable to complete the adhesion by repeatedly tapping from the back side with a brush. Next, apply it to a board using the same method as in the preparation process and leave it for about a month to air dry. This process takes advantage of the difference in elasticity of the material due to humidity to reduce distortion of the covering. The dried covering is removed from the board using a bamboo tube, spread face down on a smooth board, and the back is rubbed with a beads-sized glass bead.

This is to soften the roughness caused by the dried glue.

The above-mentioned mounting is completed by gluing the specimen (upper shaft) and the shaft to the upper and lower ends, respectively, driving a chain into a predetermined position of the specimen, and tying the string to the chain to create a hanging scroll.

The adhesive used in these processes does not dry too quickly, has adhesive strength, is easy to apply evenly, does not cause twitching, wrinkles, or distortion when drying, and does not cause mold or stains. etc. must not occur. However, nothing is known that satisfies all the conditions.

Starch-based glue, such as raw glue, which is a classic mounting glue, has the property of hardening after drying, so it tends to cause folds and cracks in hanging scrolls, scrolls, etc. In order to reduce the degree of hardening, septic paste (starch paste stored in a cool, dark place for several years after manufacture) or diluted paste may be used, but the adhesive strength is poor, so it is necessary to use a hammering brush a lot. However, it is difficult to obtain a satisfactory finish despite the skill and labor involved and the risk of damaging the calligraphy or painting. Another disadvantage of starch-based glues is that they tend to produce stains, which are thought to be caused by mold and microbial metabolic products.

On the other hand, carboxycellulose sodium (hereinafter referred to as C
(abbreviated as MC) type glue and polyvinyl acetate type glue have also been frequently used recently. Since these materials have excellent flexibility even after drying, they are less prone to bending or cracking, and have a relatively low rate of shrinkage over time, so that the entire covering is less likely to be distorted. Furthermore, the adhesive strength is superior to starch-based glues, and mold and stains are less likely to occur.

However, the permeability of CMC-based glue to the material is too high, and there is a risk that the glue will ooze out to the surface of the calligraphy and painting, staining the mounting. Furthermore, CMC/polyvinyl acetate glue has poor brush slippage during application, and the glue dries too quickly, requiring advanced techniques to uniformly apply it over a wide area.

Furthermore, when CMC-based or polyvinyl acetate-based glue is used for washi paper, it tends to become translucent, which impairs the whiteness and texture unique to washi paper, and also allows the patterns and calligraphy of the cover fabric to be seen through the back side. I can see it. As a result, the finish of the mounting material is not beautiful.

In order to prevent Japanese paper from becoming translucent due to glue, it may be possible to add a white pigment such as titanium white, but in this case, the workability of the application will be even worse, the flexibility of the glue will be lost, and the paper will feel strange. disadvantages arise.

It has been discovered that a paste containing an aqueous dispersion of fibrillated cellulose is excellent as a mounting paste, and the present invention has been achieved.

The microfibrillated cellulose used in the present invention is
It is obtained by beating purified wood pulp according to the method described in JP-A-56-100801, and is defined in the same specification as "fine fibrous hexako-su". In other words, when pulp is suspended in water and passed through a special homogenizer repeatedly under high pressure, the pulp fibers are loosened into microfibrils, which dramatically increase the surface area and water holding capacity. Obtained in form. That is, the adhesive composition of the present invention is a composition formed by mixing a CMC aqueous solution, a polyvinyl acetate emulsion, and an aqueous dispersion of microfibrillated cellulose,
The preferred range of solids content per 100 parts of the composition is:
Al with 0.5 to 5 parts of CMC, 5 to 30 parts of polyvinyl acetate, and 0.3 to 4 parts of microfibrillated cellulose.

When a hanging scroll or scroll is mounted using the adhesive, the mounted material has excellent flexibility and is therefore less prone to bending or cracking.

In addition, the rate of shrinkage over time is relatively low, and therefore the overall packaging is less likely to be distorted. The adhesive strength is also far superior to that of raw glue. Furthermore, when applying the adhesive to paper with a brush, the operability is very good, the brush glides well, and it can be applied easily and evenly.
Due to the large water-holding capacity of microfibrillated cellulose, the adhesive applied to the paper surface does not dry easily, and it is extremely easy to apply the adhesive uniformly over a wide area. In addition, the permeability of the adhesive is relatively low due to the large water-holding capacity of microfibrillated cellulose, so there is no need to worry about the adhesive penetrating the surface of the surface and staining it during lining. Another great feature is that after the backing dries, the washi paper coated with a large amount of adhesive is opaque, and the whiteness and texture of the washi characteristics are not impaired.
The finish on the back side of the cover is extremely beautiful, with almost no pattern, calligraphy, or drawings showing through from the back side of the cover.

As mentioned above, the moderately slow drying properties of the glue compositions of the present invention are favorable for operation, but this property is extremely stable under climatic conditions.

In addition, the composition of the present invention and the coverings using the same have very little occurrence of mold and stains. Furthermore, even if a preservative or a fungicide is added, the properties are hardly impaired.

The present invention will be explained below with reference to Examples.

Example CMC (Daicel Chemical Industries, CMC Daicel 1130
) 315 g of 8% aqueous solution and polyvinyl acetate emulsion (Hoechst Synthesis, Afurethane HA-10, solid content 5
0%, viscosity 110,000 cps) and aoog microfibrillated cellulose aqueous dispersion (solid content 6%) were mixed and thoroughly stirred to obtain 10'OOg of viscous glue.

When a hanging scroll was mounted using this glue, it was found to have excellent flexibility, no distortion, and the back side was beautifully finished without compromising the texture of the paper. Also, during the mounting process, gluing was extremely easy to do.

patent applicant Daicel Chemical Industries, Ltd. Hiroji Sato

Claims (1)

[Claims] An adhesive composition comprising water, a polyvinyl acetate emulsion, sodium carboxymethyl cellulose, and microfibrillated cellulose.