JPS6018982B2 - How to draw on objects with smooth surfaces - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for quickly, uniformly and faithfully drawing a pattern on the surface of an object having a smooth surface, particularly a film.

Traditionally, in the manufacturing process of textile printing screens, the original design image is separated into colors on a film, and then each part is filled in with light-blocking paint. A manual method is used to avoid overflowing or leaving unpainted areas.

However, this method not only requires skill and time to draw, but it is also difficult to paint uniformly, so it is necessary to repeatedly paint with safety in mind in order to completely provide light-shielding properties. When the coating film becomes thicker and a large number of drawing films are overlapped to make a copy, the gaps between the films also become larger, resulting in distortion of the pattern. In recent years, a method has been proposed for streamlining the drawing of such designs using machines that use equipment mainly consisting of color separation devices, but this method is inaccurate to the original drawings and has not yet been put to practical use.

As a result of intensive research into a quick and uniform drawing method that does not have the above-mentioned drawbacks, the present inventors have arrived at the method of the present invention by focusing on the interfacial characteristics between the object to be drawn and the ink.

That is, the present invention provides a surface of an object having a smooth surface,
After drawing the contour of the pattern with a substance having a critical surface tension smaller than the critical surface tension of the object, the inner surface surrounded by the contour has a smooth surface that has a critical surface tension smaller than the critical surface tension of the object and the critical surface tension of the contour-forming material. A pattern is drawn on an object having a smooth surface by supplying ink having a surface tension greater than the surface tension. When using the method of the present invention, the outline of the design is drawn by defining the surface tension of the object having a smooth surface, the outline-forming substance, and the ink, and then the ink is simply dropped or applied onto the inner surface of the outline. Since the ink is rapidly spread and applied onto a smooth surface, it is significantly simpler and the coating time can be significantly reduced compared to conventional manual application.

In addition, since the coating is based on interfacial characteristics, the coating is extremely uniform, and since the spread of ink completely stops at the contour, it is possible to draw designs that are faithful to the contour, making it suitable for use on original copies or mask films. It also has the feature that sufficient light-shielding properties can be obtained with a thin coating film, and therefore, even if a large number of drawing films are overlapped and copied, the pattern will not be distorted. Another great advantage is that no skill is required for painting. To explain the method of the present invention in more detail, objects with smooth surfaces include films, plates, and other smooth surfaces made of synthetic resins such as polyethylene, polypropylene, polypynychloride, polyvinylidene chloride, polyester, and polyamide. In addition to organic objects such as molded products, films made from cellulose derivatives such as cellophane, celluloid, and cellulose acetate, plates, and other molded products with smooth surfaces, and boards such as plywood and particle board, metal plates, Examples include organic objects such as magnetic chest plates.

It also includes sheets with smooth surfaces obtained by pressing green fabric, nonwoven fabric, or synthetic paper using a thermal calendar, or by coating, laminating, or impregnating with a resin or glue. The surfaces of these objects may be coated with a resin to adjust the surface tension, if necessary, or subjected to hydrophilic or hydrophobic treatment by corona treatment, plasma treatment, or the like. However, it is particularly effective to apply the method of the present invention to films, plates, etc. made of synthetic resins or cellulose derivatives. In addition, the contour forming material used in the present invention is a material having a critical surface tension smaller than the critical surface tension of the object having a smooth surface to which it is applied, and also a material having a critical surface tension smaller than the surface tension of the ink used. Selected substances, specifically in relation to the main solvent of the ink, the dissolution promoter of the colorant, the stabilizer to improve the adhesion of the colorant to objects with smooth surfaces, etc. However, fluorine-containing polymers, perfluorinated alkyl-containing twill water repellents, silicone resins, metal salt type twill water repellents, as well as waxes such as waxes, solid paraffins, and polyolefin waxes are preferred. Among these, fluorine-containing polymers, perfluorinated alkyl group-containing water-repellent oils, silicone resins, and the like are particularly preferred. When using ink that uses water as a colorant dissolution promoter for painting, if the contour-forming substance is highly liquid-repellent such as paraffin, once the ink has spread to the contour, it will spread due to the liquid-repellent action of the contour-forming substance. In some cases, it may recede and make it impossible to obtain an even coating, but in such cases, it is necessary to use a contour-forming material that has an appropriate critical surface tension, or to mix and match contour-forming materials with different critical surface tensions, or to use an ink. This problem can be solved by appropriately selecting the composition, and the object of the present invention can be achieved. Critical surface tension of typical synthetic resins used as objects with smooth surfaces to which the present invention is applied, typical fluorine-containing polymers used as contour-forming substances, perfluorinated alkyl-based water-repellent agents, etc. are shown in Table-1. Table-1 Critical surface tension of substances 1) 2) 1) Polymers Vol. 17, p. 680, 1968 2) Journal of Applied Polymer Science Vol. 12, p. 719, 1968 3) Surface tension of melt polymer at 150°C The surface tension of the solid polymer obtained by extrapolating to the value at 20°C from A solution or dispersion consisting of a pigment, a vehicle, an auxiliary agent, etc., with a liquid having tension as the main solvent*
*It is.

Table 2 shows the surface tension of various solvents and especially the spreadability of these solutions on polyethylene terephthalate films suitable for application of the present invention. Table 2 Surface tension of liquid and spreadability on polyethylene terephthalate film 1
) According to the Chemical Handbook (edited by the Chemical Society of Japan, 1952 edition) 2)
Drop 0.1 of the solution Z onto the spreadable horizontal film,
It is expressed as the average diameter of the expanded portion after 0 and 30 seconds.

sp: Complete spreadability NO: No spreadability observed.

Generally, the spread of a solution on the surface of an object is determined by the tension of each interface, and in order for the solution to spread on the surface of the object, the surface tension of the solution must be smaller than the critical surface tension of the object.

However, the main solvent of the ink used in the present invention needs to be determined by taking into account the spreading speed, coloring, solubility of inscriptions, drying speed, stopping of spreading at the contour part due to the contour forming substance, etc. The solvent having a boiling point of 60 to 100 qo is preferable, and ethanol, isopropanol, ethyl chloride, etc. are particularly preferable. To explain the coating method of the present invention, after drawing the outline of an arbitrary design or character using an outline-forming substance on the surface of an object having a smooth surface, ink is poured onto the inner surface of the outline, dripping, etc. It can be supplied by any means.

The outline can be formed by drawing with a molten solution of the contour-forming substance or a suitable solvent solution or dispersion, by heating and pressing thin pieces of the substance, or by directly drawing with wax, paraffin, etc. in solid form. be done. When the contouring material is used in solution form, it is generally preferred that the ink be applied after the material has solidified or dried. According to the method of the present invention, coating can be done evenly with extremely simple operations, so it can be widely applied to coloring a large number of sheets when creating a picture, drawing designs on the surface of a plastic board, etc.

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

Note that parts in the examples are parts by weight. Example 1 After drawing the outline of a pattern on the surface of a polyester film using solid paraffin, ink having the following composition was dropped onto the center of the inner surface of the discussion area at a ratio of 0.01 to 0.02.

Ink Ethyl acetate 9 parts oil-based ink 1 part vehicle obtained from ceramic resin/linoleic acid polymer/pentaesthritol 1 part base and black basic dye/5 parts lake dye obtained from alum 85 parts toluene The ink dissolved in the ink instantly spread and reached the outline, creating a pattern that was faithful to the outline.

As a result, since the painted surface was excellent in uniformity, it was possible to obtain a copy original with sufficient light-shielding properties with a thinner coating film than in conventional manual painting methods.

Example 2 Oil-based ink 7 used in Example 1 was applied to the surface of the photographic film, Asahi Guard AG-630 (produced by dissolving an organic oil repellent in Kixylol, manufactured by Meisei Kagaku Kogyo Co., Ltd.) 3
After drawing the outline of the design using the mixed liquid consisting of the base, the ink used in Example 1 was dropped onto the center of the inner surface of the outline at a ratio of 0.02'/carp using a graduated dropper.

The ink spread instantly and evenly coated the inner surface of the contour, forming a pattern. Example 3 A pattern was drawn in the same manner as in Example 2 on the surface of a polypropylene film whose wettability had been improved by corona discharge treatment.

Claims (1)

[Claims] 1. After drawing the outline of a pattern on the surface of an object with a smooth surface using a substance that has a critical surface tension smaller than the critical surface tension of the object, the critical surface of the object with a smooth surface is drawn on the inner surface surrounded by the outline. A method of drawing on an object having a smooth surface, characterized in that an ink having a surface tension smaller than the surface tension and larger than the critical surface tension of a contour forming substance is supplied.