JPH0368913B2 - - Google Patents

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 adhesives make a huge contribution. be.

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. After letting it dry naturally, add some moisture from 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 temporarily paste it (wash paper is placed on a sliding door-like stand made of sturdy thin wood pieces). Paste several sheets on top of each other and place them on 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.

Using a bamboo spatula, peel off the temporary covering, cut the prepared mounting object and mounting material into the required shape and size, and paste and connect them together using mounting glue (called tsuke mawashi). Adjust the form. 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 hitting the adhesive from the back side using a hammer brush. Next, apply it to the temporary paste in the same way as the preparation process,
Leave it for about a month and let it dry naturally. 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 peeled off from the temporary cover using a bamboo spatula, spread face down on a smooth board, and the back side 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 a marker (upper shaft) and a scroll to the upper and lower ends, respectively, driving a chime into a predetermined position on the marker, and tying a string to create a hanging scroll.

The adhesive used in these processes should not dry too quickly, have adhesive strength, be easy to apply evenly, and not cause twitching, wrinkles, or distortion when drying, and should 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 you have 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 abbreviated as CMC) based glue and polyvinyl acetate based glue have recently been widely used. Since these materials have excellent flexibility even after drying, they are less prone to bending or cracking, and have a relatively low shrinkage rate 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, CMC glue has too high permeability to the material, and the glue oozes out to the surface of the calligraphy and painting.
There is a risk of staining the covering. Additionally, CMC/polyvinyl acetate glue has poor brush slippage during application.
Also, the glue dries too quickly, requiring advanced techniques to apply it evenly over a large area.

Furthermore, when CMC-based or polyvinyl acetate-based glue is used on Japanese paper, the paper tends to become translucent.
The whiteness and texture unique to washi paper are lost, and the patterns and calligraphy of the cover cloth can be seen through the back side. 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 becomes worse, the flexibility of the glue is lost, and it gives a strange feeling. occurs.

As a result of intensive studies to compensate for the drawbacks of conventional glues as described above, we found that CMC/polyvinyl acetate emulsion with an aqueous dispersion of microfibrillated cellulose added is an excellent adhesive for mounting. Heading, we arrived at the present invention.

The microfibrillated cellulose used in the present invention is made from purified wood pulp according to Japanese Patent Application Laid-Open No. 56-100801.
It is obtained by beating according to the method shown in the specification, and is defined in the specification as "microfibrous cellulose". In other words, when pulp is suspended in water and repeatedly passed through a special homogenizer under high pressure, the pulp fibers are loosened into microfibrils, which dramatically increase the surface area and water holding capacity, resulting in the formation of an aqueous dispersion. It can be obtained with That is, the adhesive composition of the present invention has CMC
In a composition formed by mixing an aqueous solution, a polyvinyl acetate emulsion, and an aqueous dispersion of microfibrillated cellulose, the preferred range of solid content per 100 parts of the composition is 0.5 to 5 parts of CMC, polyacetic acid 5 to 30 parts of vinyl 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 much better than that of raw glue. Furthermore, when applying the adhesive to paper with a brush, the operability is very good, as the brush glides well and can be applied easily and evenly, and even during dry summer months, microfibrillated cellulose has a large water-holding capacity. Therefore, the adhesive applied to the paper surface does not dry easily, and it is extremely easy to uniformly apply the adhesive over a wide area. Furthermore, the permeability of the adhesive is relatively low due to the high water retention capacity of microfibrillated cellulose, so there is no risk of the adhesive penetrating the surface of the facing and staining it during backing.
Another great feature when using this adhesive is that after the backing dries, the washi paper coated with a large amount of this adhesive is opaque, and the whiteness and texture of the washi are not lost, and the paper can be easily attached to the surface from the back side. The design, calligraphy, and paintings are hardly visible through the cover, and the finish on the back of the cover is extremely beautiful.

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 further explained by giving examples below.

Example CMC (Daicel Chemical Industries, CMC Daicel 1130)
315g of 8% aqueous solution and polyvinyl acetate emulsion (Hoechst Synthesis, Abretan HA-10, solid content
50%, viscosity 110,000 cps) and 300 g of microfibrillated cellulose aqueous dispersion (solid content 6%) were mixed and sufficiently stirred to obtain 1000 g of viscous paste.

When I used this glue to cover a hanging scroll, it was found to have excellent flexibility, no distortion, and the back side was beautifully finished without damaging the texture of the paper. Also, during the mounting process, gluing work could be done very easily.

Claims (1)

[Claims] 1. An adhesive composition comprising water, polyvinyl acetate emulsion, sodium carboxymethyl cellulose, and microfibrillated cellulose.