JPH0359751B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to marking on the surface of metal, glass, plastic, wood, or a non-liquid-absorbing substrate on which a water-resistant coating is applied to the surface thereof. The present invention relates to an easily removable marking method which allows marking to be simply and easily removed (erased) and which can be repeatedly performed.

<Prior art> Temporary display means, such as welcome signs for inns, temporary advertising signs for shops, and window decorations have conventionally used water-based paints,
Marking was performed using a marking agent consisting of a colored pigment, water, and, if necessary, a small amount of a water-soluble resin.

In addition, signposts, wreaths, name plates attached to flowers, etc. used at funerals were usually made of solid wood with brushstrokes written in ink or other ink.

<Problems to be Solved by the Invention> However, since the water-based paints, marking agents, or ink described above are water-soluble, the markings are likely to smear or disappear when wet due to rain, etc., and the strength of the film may be reduced. In addition, there were various drawbacks such as the fact that if the marking film was touched, it would contaminate what it touched.

In addition, if the surface of the substrate used is rough, the marking agent may remain in the minute recesses even after the marking film is removed.
(In other words) it had the disadvantage of being difficult to remove.

Furthermore, if a liquid-absorbent wooden board is used as a substrate, the marking agent used will seep into the interior, so after use, it will be necessary to scrape off the surface layer with a plane etc. (for reuse). Therefore, in addition to the disadvantage that it was very time-consuming, it also had the disadvantage that the thickness of the board became thinner after repeated use.

Therefore, conventionally, after the board is used, the surface of the board is painted over.
A method of erasing the markings has also been used, but this method also requires a coating agent to erase the markings, making it uneconomical. This method has the disadvantage that it cannot be applied in such cases.

The present invention was made in view of the current situation, and aims to eliminate or improve the various drawbacks mentioned above.

In other words, the present invention makes it difficult for the marking to disappear even if it gets wet with rain, etc., does not cause contamination even if the marking film is touched, and in addition, the marking can be easily and completely removed after use, and there is no possibility of repeating. It provides a certain marking method.

<Means for solving the problems> That is, the present invention provides (i) an average degree of polymerization of about 700 to 2400, a degree of butyralization of about 700 to 2,400;
75% by weight or more polyvinyl butyral emulsion resin...100 parts by weight, (ii) Plasticizer...20-50 parts by weight, (iii) Color pigment...5-120 parts by weight, (iv) Water... ...100 to 1000 parts by weight of a water-swellable colored peelable paint is used to mark the surface of a non-liquid-absorbing substrate for use.
The present invention also relates to an easily removable marking method characterized in that, after the marking film is used, the marking film is washed and removed with an aqueous removal liquid.

The present invention will be explained in more detail below.

First, in the present invention, a "non-liquid-absorbing substrate" to which a peelable paint is applied is a substrate that does not substantially absorb water-swellable colored peelable paint, which will be described later, when marked with the paint. It can be used without any particular restrictions. For example, aluminum, iron,
Typical examples include metal plates such as stainless steel, plated plates; plastic plates such as polyvinyl chloride, acrylic resin, and polycarbonate; rubber plates; ceramic plates; glass plates, laminates of these, and coated substrates. It is mentioned as a thing.

It can also be used as a marking agent for liquid-absorbing wood boards, such as veneer decorative boards made by gluing sliced veneers onto veneer boards made from natural wood, plywood, particle boards, fiber boards, etc. A wooden board coated with a water-resistant coating or the like to prevent absorption of water is also applicable to the present invention.

In the present invention, desired characters, symbols, figures, etc. are marked on the surface of such a substrate using a "marking agent" described below.

As will be described later, the marking agent used in the present invention is one that swells when water or an aqueous removal solution containing water as its main component is applied, resulting in a decrease in adhesion to the substrate (water-swellable). Any colored peelable paint can be used. For example, it consists of a polyvinyl butyral emulsion resin, a plasticizer, a color pigment, and water.

The polyvinyl butyral emulsion resin preferably has an average degree of polymerization of about 700 to 2,400, particularly preferably 900 to 2,000, and a degree of butyralization of about 75% by weight or more.

In addition, if the average degree of polymerization is lower than the above range, the strength of the marking film obtained will be insufficient, and as a result, the marking agent will become fine when the marking film is removed and will tend to remain in the fine recesses of the substrate, causing contamination.
On the other hand, if it exceeds the above range, emulsification becomes difficult and a stable marking agent cannot be obtained.

Furthermore, if the degree of butyralization is lower than the above range, it becomes water-soluble and tends to remain in minute recesses on the surface of the substrate when the marking film is removed, causing contamination.

In the present invention, a plasticizer is used. Examples of the plasticizers include glycols such as polyethylene glycol and triethylene glycol, phosphates such as tricresyl phosphate, phthalates such as dibutyl phthalate and dioctyl phthalate, and sebacates such as dibutyl sebacate and dioctyl sebacate. Typical examples include fatty acid ester, castor oil, and chlorinated paraffin.

The appropriate amount of the plasticizer is 20 to 50 parts by weight per 100 parts by weight of the polyvinyl butyral emulsion resin. If the blending amount is less than the above range, a sufficient adhesion reducing effect cannot be obtained when removing the marking film with an aqueous removal liquid, and the marking film tends to lack flexibility. On the other hand, if the amount is too large than the above range, the marking film tends to become sticky, and it also becomes difficult to remove the marking film cleanly.

In the present invention, colored pigments are used. As the coloring pigment, common paint pigments such as carbon black, titanium oxide, phthalocyanine blue, and yellow lead can be used. The blending amount varies depending on the oil absorption amount, coloring power, hiding power, etc. of the pigment, but it is usually 5 to 5 parts by weight per 100 parts by weight of polyvinyl butyral emulsion resin.
120 parts by weight is suitable.

Water is used in the present invention. Water is 100 parts by weight for 100 parts by weight of polyvinyl butyral emulsion resin.
~1000 parts by weight is appropriate, and the amount of water may be determined by considering marking workability, film thickness, etc.

The marking agent used in the present invention comprises, in addition to the above-mentioned components, various extender pigments, additives, etc. as required.

The marking agent used in the present invention, the "water-swellable colored peelable paint," consists of the above-mentioned components. Marking is performed in an arbitrary shape by various means such as , spraying, etc.

Note that when the marking agent forms a marking film, if it is water-soluble, the marking film tends to wash out due to rain outdoors, or the pigment in the marking agent tends to remain in minute recesses on the substrate surface. It is not appropriate because of

On the other hand, in the present invention, even if the marking film gets wet due to rain, etc., the marking film only swells at most, so the entire film is integrated. It has the advantage of not leaving any residue in the concave areas.

In the present invention, after marking in this manner and using it for its intended purpose, the marking film is washed and removed using an aqueous removal solution.

The aqueous removal liquid used in the present invention is
When the surface of the marking film is wetted by means such as coating, it penetrates into the marking film, swells the marking film, and reaches the substrate interface, thereby weakening the adhesion between the marking film and the substrate. It has the following.

Note that among the aforementioned aqueous removal liquids, those that substantially dissolve the marking film are not suitable because the pigment tends to remain in the fine recesses on the surface of the substrate.

In the present invention, the aforementioned aqueous removal liquid includes water or water and methyl alcohol, ethyl alcohol,
Propyl alcohol, butyl alcohol, cellosolves, carbitols, ethylene glycol,
A mixture with a solvent such as glycerin, or a mixture of these with various surfactants to increase permeability as necessary, is used.

In the above, for example, the appropriate mixing ratio of water and the alcohol is 100/0 to 70/30.

In the present invention, the marking film is removed by impregnating the marking film with an aqueous removal liquid by means such as coating, leaving the marking film to swell for several tens of seconds to several tens of minutes, and then
A method of rubbing off with a cloth, brush, sponge, etc. is suitable. Other methods include various means such as jetting high-pressure water.

<Effects of the Invention> According to the method of the present invention, since a water-swellable colored peelable paint is used as the marking agent, the marking film will not be eluted even if it gets wet with rain or the like.
It just swells and therefore the marking does not disappear. Moreover, even when the marking is removed, the marking film can be cleanly peeled off and removed without any pigment remaining in the minute recesses on the substrate surface.

Therefore, it is possible to repeatedly mark and remove markings without filling the markings or scraping the surface of the substrate.

The present invention will be explained in detail below with reference to Examples. In the examples, "parts" and "%" are expressed on a weight basis.

[Preparation of marking agent A]

Polyvinyl butyral resin (average degree of polymerization 1000,
Butyralization degree 78%), 100 parts of dioctyl phthalate, 30 parts of castor oil, and 5 parts of anionic surfactant were heated to 120°C with stirring to form a homogeneous solution, and then 140 parts of water was gradually added dropwise. An emulsion was prepared.

Add carbon black to 30 parts of the resulting emulsion.
Marking agent A was prepared by mixing and stirring 2.5 parts of calcium carbonate, 20 parts of calcium carbonate, 1 part of polyether ester thickener, and 45 parts of water.

[Preparation of marking agent B]

Polyvinyl butyral resin (average degree of polymerization 920,
Butyralization degree 76) 100 parts, dibutyl sebacate
20 parts of triethylene glycol, 5 parts of triethylene glycol, and 5 parts of anionic surfactant were heated to 120° C. with stirring to form a homogeneous solution, and then 130 parts of water was gradually added dropwise to form an emulsion.

30 parts of the obtained emulsion, 15 parts of titanium oxide,
Marking agent B was prepared by mixing and stirring 3 parts of silica and 50 parts of water.

[Preparation of marking agent C] Polyvinyl butyral resin with a degree of polymerization of 300,
Marking agent C was prepared in the same manner as marking agent A except that a butyralization degree of 73 was used.

Example 1 Characters were written on a hard polyvinyl chloride board (600 x 500 x 3 mm) using a brush, and
It was left undisturbed for a day. The marked polyvinyl chloride plate was stood vertically outdoors and left for 10 days, but no abnormality was observed in the marking film.

Next, spray water on the surface of the left-over polyvinyl chloride board, leave it at room temperature for 5 minutes, and then
While pouring water, rotate (200r.pm) a circular brush (φ120mm) made of nylon (diameter 0.5mm).
The marking film was rubbed off. The marking film could be easily removed without leaving any traces.

Comparative Example 1 Marking was carried out in the same manner as in Example 1 using Marking Agent C instead of Marking Agent A, and the marking film was rubbed off by the same means. However, markings remained in minute recesses on the surface of the polyvinyl chloride, and it took about three times as long as in Example 1 to completely remove them.

Example 2 After lightly sanding an oak veneer (200 x 600 x 10 mm) with abrasive paper, apply a urethane sanding sealer, let it dry, then sand and smooth it, then apply a urethane clear paint. Dry.

Marking agent B was written on the wooden painted board thus prepared using a brush, and the board was allowed to stand at room temperature for one day.

The marked wooden painted board was vertically stood outdoors and no abnormality was observed in the marking film even after it was left for one week.

Next, an aqueous removal solution consisting of 70 parts of water, 20 parts of ethyl alcohol, and 10 parts of butyl carbitol was sprayed onto the surface of the wooden painted board left as described above, and the marking film was rubbed off in the same manner as in Example 1. ,
The marking film could be easily removed without leaving any traces.
After repeating this process 10 times, there was almost no change in the surface of the wooden painted board, and there was no change in the ease of removing the marking film.

Claims (1)

[Scope of Claims] 1 (i) Polyvinyl butyral emulsion resin with an average degree of polymerization of about 700 to 2400 and a degree of butyralization of about 75% by weight or more...100 parts by weight, (ii) Plasticizer...20 to 50 Parts by weight, (iii) Colored pigment: 5 to 120 parts by weight, (iv) Water: 100 to 1000 parts by weight. 1. An easily removable marking method, characterized in that the marking film is removed with an aqueous removal solution after the marking film is used and the marking film is used.