KR890003617B1 - Production of chemical mat film for drawing - Google Patents

Abstract

A film having tough surface is prepd. by coating a mixt. of melamine resin, cellulose acetate resin, nitro cellulose resin, glass powder and silica powder to one or both surfaces of polyester film. Thus, 600 wt.parts melamine resin, 200 wt. parts cellulose acetate, 300 wt. parts nitro cellulose, 200 wt. parts mat agent such as silica, 100 wt. parts starch, 25 wt. parts antistatic agent and 25 wt. parts wax are mixed with ball mill for 48hr to give a base material for film treatment. The base material is dissolved in toluene and isopropyl alcohol and coated 75 μm thick on the polyester film and dried at 180≰C for 2.5-30 sec to give transluscent drawing film.

Description

Manufacturing Method of Chemical Matte Film for Drawing

1. The present invention relates to a manufacturing method of a chemical mat film for drawing, more specifically, based on a polyester film having a suitable thickness, the surface of the melamine resin, fibrous resin-based cellulose acetate resin and nitro The manufacturing method of the mating film for drawing into which the roughening layer (synthetic resin layer which has a hard surface) was formed by mixing and apply | coating glass powder, a silica powder, etc. uniformly to the mixture which consists of three types of synthetic resins of a cellulose resin.

Conventionally, drawing paper or transparent processing paper (tracing paper) is used, but this type has a disadvantage in that it is inferior in physical strength and dimensional stability and cannot be stored for a long time. Accordingly, in order to eliminate these disadvantages, a roughening layer is formed on the surface of the polyamide, polycarbonate, or polyester film as a base, and the writing is possible with a pencil or ink. In particular, the polyester film is widely used as the base of the drawing film because it has a strong physical strength (heat resistance, tensile strength, burst strength), excellent dimensional stability, and excellent in heat resistance, moisture resistance, and chemical resistance. However, the polyester film cannot obtain sufficient adhesion between the film and the roughening layer when the roughening layer is formed on the surface due to its chemical resistance, i.e., stability to acids, alkalis and organic solvents. Therefore, various methods for improving the adhesion thereof have been proposed. As an example, a method of roughening the surface of a film by physically or chemically pretreating the surface of the film or forming a primer layer with a binder of a mat layer on the surface of the film to increase the adhesion between the mat layer and the polyester film is disclosed. (Japanese Patent Application Publication No. 34-9167, US Patent No. 2627088), but this method has a problem of high manufacturing cost because of the pretreatment process.

There has also been disclosed a method of adding a curing agent by mixing a resin such as a thermosetting acrylic resin, an amino resin, an epoxy resin, a vinyl chloride copolymer resin, and firmly adhering the mat layer to the surface of the film without pretreatment (Japan). National Patent Application Publication 49-37585).

However, this method must accurately adjust the amount of hardener. If the amount of hardening agent is too large, the curing reaction is too much and the change of adhesive strength and roughening layer occurs, and if it decreases, the roughening layer changes, and if it decreases, the roughening does not become hard and soft, and when used as a drawing pencil, the roughening layer This is disturbed. Also, even when the amount of curing agent is appropriate, the curing time for heat is long (5-7 minutes at 150 ° C. or 7-10 minutes at 140 ° C.), and the forming agent is added as time passes after mixing the roughening agent with the curing agent. There are many losses because they harden, which also raises the cost increase rate.

Film suitable for drafting should not be dried with improvement, tear strength, resistance to fracture, should be stable against high intensity UV and heat, should not be peeled off, should not have dimensional change due to changes in temperature and relative temperature, and should be kept short in heat shrinkage. There should be no dimensional change and discoloration and good handwriting as drawing ink and pencil. In addition, after writing, it has excellent erase performance, the matte layer should not fall, and the copy should be well.

MEANS TO SOLVE THE PROBLEM The present inventor has carried out research to solve the above-mentioned shortcomings and to obtain a film which can satisfy the above requirements, and has mixed melamine resin, cellulose acetate resin, which is a fibrous resin, and nitrocellulose resin, and a silica powder, etc. It was used to obtain the braking chemical mat film excellent in dimensional stability, heat resistance, chemical resistance and water resistance by making the roughening layer on the surface of the polyester film using the composition which disperse | distributed.

Therefore, the drafting chemical mat film according to the present invention is mixed melamine resin, cellulose acetate resin and nitrocellulose resin in a weight ratio of 100 to 800: 100 to 600: 100 to 600 each by weight and the mat for 1000 parts of the mixture 100 to 200 parts by weight, 100 to 150 parts by weight of a water-soluble substance, 10 to 50 parts by weight of an antistatic agent, and 10 to 50 parts by weight of a wax forming solution, wherein the polyester is applied to one or both sides of the film at 180 ° C. Obtained by heat treatment at 25 to 30 seconds.

In addition to silica and glass powder, the mat agent used in the present invention may be any conventional mat agent used in the art, such as titanium oxide, diatom, bentonite or calcium carbonate.

Water-soluble substances used in the present invention include starch, casein, methyl cellosolve, polyvinyl pyrrolidone, polyvinyl alcohol, gelatin, water-soluble alkyd resin, maleic anhydride, fumaric acid and the like.

Hereinafter, the present invention will be described in detail with reference to Examples. As a base film, it is a polyester film produced domestically and abroad, The thickness of 25-150 micrometers is good.

Example 1

1) 200 parts by weight of silica as a mat agent, 100 parts by weight of starch as a water-soluble substance, 25 parts by weight of an antistatic agent, to a resin mixture obtained by mixing 600 parts by weight of a meltin resin, 200 parts by weight of cellulose acetate resin and 300 parts by weight of nitrocellulose. 25 parts by weight of wax is added and mixed with a ball mill for 48 hours to prepare a stock solution. Toluene, isopropyl alcohol, methyl ethyl ketone, methyl isobutyl ketone or acetone was used as the diluting solvent. The roughening liquid obtained as mentioned above was apply | coated smoothly to 74 micrometers polyester film, and it processed and dried at 180 degreeC for 25 to 30 second, and obtained the translucent drafting film which has a roughening layer of 6-10 micrometers in thickness.

The drawing film obtained by the above method has extremely good adhesion between the film and the rough layered layer. Almost no change was observed even in the experiment. In the chemical resistance test, a strong solvent such as methyl ethyl ketone was rubbed with gauze 20 times, but little change was made on the surface of the formation layer. Because Constant ¹⁰ 10 Ω and a surface resistance checks were not contaminated with dust and eraser dust. A hard pencil such as re-coated 5H-9H was enough to withstand the roughening layer thus obtained, and there was no groove-like trace on the forming layer.

Example 2

3 parts by weight of a smoothing agent (dispersant) was added to the stock solution of Example 1 (to prevent agglomeration between silica, a water-soluble substance, and starch, a water-soluble substance), and 20 parts by weight of a fluorescent whitening agent were added. Obtained a drawing paper.

Example 3

As described in Example 1, the test was carried out by replacing 100 parts by weight of silica or less than 200 parts by weight of starch instead of 200 parts by weight of silica made of metme and 100 parts by weight of water-soluble substance. When the pencil was used, such as 5H-9H for drawing, it could not stand enough, and the drawing paper was not practical.

Example 4

The same coating liquid as in Example was applied under the same conditions, followed by heat treatment drying at 150 ° C. for 40 seconds to 50 seconds to test in Example 1, but the hardness of the roughening layer was lowered and the adhesion was weakened, resulting in inferior practicality.

Summarizing the test results for the drafting chemical matte film according to the present invention are as follows.

CONCLUSIONS: The hardness and roughness of the roughening layer, the weakening of adhesion and the aging time are considered to be ineffective and impaired.

As described above, the surface of the (one-component) polyester film is roughened using a composition obtained by mixing melamine resin, cellulose acetate which is a fibrous resin system, and nitrocellulose resin and dispersing it with silica powder or the like. By forming the forming layer, the pretreatment is not required, and the curing time is shorter than the two-component method using hardened paper, and there is no loss of the mixing agent. By mixing at a specific ratio, the process is simple and the obtained roughening layer has the advantage of obtaining excellent effects such as dimensional stability, heat resistance, chemical resistance and water resistance.

Claims (2)

In the drawing chemical mat film having a roughening layer directly on one side or both sides of a polyester film, 100 to 200 weights of mat agent based on 1000 parts by weight of a mixture of melamine resin, cellulose resin of fibrous resin system, and nitrocellulose resin Part 1, 100 to 150 parts by weight of a water-soluble substance, 10 to 50 parts by weight of an antistatic agent and 10 to 50 parts by weight of wax is applied to the film to form a roughening liquid, characterized in that the heat treatment and drying for 25 to 30 seconds at 180 ℃ Method for producing a chemical matte film for drafting. The method of claim 1, wherein the mixing ratio of the melamine resin, the fibrous cellulose acetate resin, and the nitrocellulose resin is 100 to 800: 100 to 600: 100 to 600, respectively, by weight. Manufacturing method.