JP2002177876A - Method for removing coating film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for removing a coating film, by which a coating film can be peeled off easily in a short time while suppressing the damage and deterioration of an object-to-be-coated. SOLUTION: This method for removing a coating film 1 from the surface of an object-to-be-coated 5 comprises a process for supplying a polishing agent 2 to the surface of the coating film 1, pressing the polishing agent 2 against the surface of the coating film 1 by the pushing face 77 of a pressure body 7, and crushing the coating film 1 to form a crushed coating film 15, and a process for removing the polishing agent 2 and the crushed coating film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing a coating film applied to a floor material or the like.

[0002]

2. Description of the Related Art Many methods for removing a coating film have been studied.
For example, as a method of physically removing the coating film, there is a method of shaving using a polishing paper or a grinder. In this method, when the thickness of the coating is uneven or the surface of the coating is uneven, the coating and the coating are also cut at the same time as the coating. In many cases, the substrate is scratched. If the surface of the coating is gradually scraped so as not to damage it, it takes an extremely long time to completely remove the coating.

Further, there is a sand blast method as a coating film removing method. This method fires powder such as sand at high speed,
It removes the coating film by giving an impact. This method
If the object to be coated is soft, such as plastic or wood, the impact often causes defects such as dents and scratches. This method can only impact a small area at a time. Therefore, if the coating is performed little by little so as not to dent or damage the coating, it takes an extremely long time to completely remove the coating.
In addition, there is a method of removing the coating film by hitting it with a hammer. This method is used to remove a coating film that has accumulated on a coating jig, but often deforms an object to be coated.

[0004] As a method of chemically removing a coating film, there is a method of decomposing and dissolving a coating film with a chemical called a release agent. With this method, if you want to completely remove the coating,
It is necessary to use a strong release agent. In this case, an object to be coated such as plastic, wood, or marble is often swelled or dissolved.

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention provides a method for removing a coating film which can easily and easily peel off a coating film in a short time while suppressing damage and deterioration of an object to be coated. It is something to offer.

[0006]

According to a first aspect of the present invention, there is provided a method for removing a coating film from the surface of an object to be coated, wherein an abrasive is supplied to the surface of the coating film, and the abrasive is applied to the coating surface by a pressing surface of a pressing body. A method for removing a coating film, comprising: pressing the coating film on the film surface to crush the coating film to form a crushed coating film; and removing the abrasive and the crushed coating film.

In the method for removing a coating film according to the present invention, an abrasive is supplied to the surface of the coating film, and the abrasive is pressed from above by a pressing body. By pressing the abrasive,
Normally, the coating film is crushed within a few seconds to form a crushed coating film having crushed pieces of the coating film. The crushed pieces can be easily collected in a short time by suction or the like. In addition, the coating film is crushed only by pressing the abrasive, but the coating object under the coating is scarcely damaged. In addition, since the coating film is crushed by physical action, it can deform, swell, dissolve,
Does not cause degradation such as decomposition. Therefore, according to the present invention, it is possible to easily remove the coating film in a short time while suppressing damage to the object to be coated.

It is preferable that a release agent is applied to the surface of the crushed coating film. This gives
The coating is dissolved by the release agent, and the adhesion of the coating to the surface of the object to be coated is significantly reduced. For this reason, the coating film is more easily removed. Crushed coatings are preferred over uncrushed coatings. When the coating film is crushed, the contact area with the release agent increases, so that the release agent works more effectively.

The release agent used in the present invention is a chemical intended to peel off a coating film, and is used after being applied to the coating film. The release agent must be one that does not deform, swell, dissolve or decompose the object to be coated. As such a release agent, for example, a coating film release agent or a wax release agent can be used, as well as JP-B-7-78240.
Japanese Patent Publication No. 6-70201, Japanese Patent Publication No. 6-33
429, JP-A-9-132739, and JP-A-9-241687 can be used. The release agent may be organic solvent-based or water-based.
Its form may be anything. When used in on-site construction, a water-based type with low odor and no danger of ignition is preferred.

It is preferable that at least the lowermost layer in the coating film has a property of dissolving in the release agent. Since the upper layer of the coating film has been crushed by the release agent, the lowermost layer has appeared on the surface or cracks have reached. Therefore, the release agent reaches the lowermost layer in a short time, and dissolves the coating film. As a result, removal of the coating film becomes easier.

In examining whether at least the lowermost layer of the coating film can be dissolved in the release agent, the following method can be used. The lowermost coating film is formed on a smooth and chemically stable substrate such as a glass plate. A predetermined release agent is spotted thereon, and after 30 minutes, the release agent is removed. At this time, at least the lowermost layer of the coating film can be said to have dissolved if the coating film is swollen or softened as it is at the time of formation, or is easily removed together with the release agent. On the other hand, when the coating film remains as formed, does not swell or soften, and is difficult to remove, it can be said that at least the lowermost layer of the coating film did not dissolve.

The pressing body is a jig for pressing the abrasive against the surface of the coating film. It is preferable that the pressing surface of the pressing body is a curved surface. If the pressing surface is flat, the abrasive cannot be pressed uniformly onto the coating film surface, and the efficiency of removing the coating film may be reduced. This tendency is particularly high when the surface of the article to be coated has irregularities. If the pressing surface is sharp, the surface of the object to be coated may be damaged when the pressing body is moved.
Therefore, it is preferable that the pressing surface be a smooth curved surface as described above.

According to a fifth aspect of the present invention, the pressure body is
Preferably, it is a rotating wheel that rotates freely. As a result, the abrasive uniformly penetrates the coating film surface regardless of the unevenness of the coating film surface. For this reason, when the coating film is removed, the coating object is less likely to be damaged. Further, a pressurized body composed of a rotating wheel is particularly preferable for an object to be coated having severe irregularities. The rotating wheel has, for example, a cylindrical or spherical shape capable of moving in all directions without any trouble. The rotating wheel includes, for example, metals such as steel, stainless steel, and brass, ceramic, plastic, and rubber. Among these, metals and ceramics are preferred from the viewpoint of wear resistance.

According to a sixth aspect of the present invention, the rotating wheel includes:
It is preferably mounted on a rotating pedestal that rotates. Thereby, the abrasive can be uniformly penetrated into the coating film, and the coating film removal efficiency is further improved. Therefore, the coating film can be easily removed in a short time without shaving or damaging the convex portion of the object to be coated. The number of rotating wheels fixed to the rotating pedestal may be any number, but is preferably three or more in order to stably drive the rotating pedestal on the abrasive. Furthermore, to suppress vibration during driving,
The rotating wheel may be fixed to the rotating pedestal with a cushion material such as rubber, plastic, or metal interposed therebetween.

According to a seventh aspect of the present invention, it is preferable that the pressing surface of the pressing body is a curved surface that is curved in the moving direction. As a result, the abrasive can be uniformly penetrated into the coating film without damaging the object to be coated.

According to the present invention, it is preferable that the pressing surface of the pressing body is pressed a plurality of times against the surface of the coating film to which the abrasive has been supplied. As a result, the abrasive material sufficiently penetrates the coating film, so that the coating film is easily crushed, and the coating film removal efficiency is improved. The movement of the pressure body is
It may be performed manually or automatically by a machine.

As the above abrasive, for example, an abrasive,
There is abrasive paper. The abrasive is a powder composed of particles having relatively high hardness, and has a particle size (JIS R60).
10) is not particularly limited, and may be selected according to the thickness of the coating film. The particle size of the abrasive is preferably larger than the thickness of the coating film. As a result, the crushing force of the coating film increases, and the efficiency of removing the coating film increases. For example, if the coating thickness is 5
In the case of ３０30 μm, the particle size of the abrasive is P50〜400.
It is preferred that If it is less than P50, the distance between the abrasives on the surface of the coating film will be widened, and there will be places where it cannot be pressed against the coating film, which may reduce the efficiency of removing the coating film. Becomes smaller,
Only the shallow part of the coating film surface is crushed, and the efficiency of removing the coating film may be reduced.

The abrasive may be an inorganic compound such as a metal compound or ceramic, or may be a powder made of an organic compound obtained by pulverizing plastic particles or cellulose.
Abrasives suitable for the method of removing the coating film include diamond, alumina, corundum, emery, garnet, gold sand, silicon carbide, boron nitride, diatomaceous earth, silica sand, silicon oxide, iron oxide, chromium (III) oxide, and oxide. Cerium (I
V). Of these, alumina, corundum, and silica sand are preferred because they are inexpensive.

The above-mentioned abrasive paper is paper or cloth to which powder has been adhered, and is used for scraping or sharpening the surface of a coating film. This powder often uses the above abrasive.
Examples of abrasive paper include Kovacs, Sumitomo 3
M, Japan Coated Abrasive Co., Ltd. and Fuji Tombo Co., Ltd.

The above-mentioned coating film is a film formed by curing a coating liquid after application of an object to be coated. The coating film is formed from an organic compound or an inorganic compound or a mixture thereof. When the object to be coated is a floor, the coating film is formed, for example, by applying a paint or floor polish and curing.
Further, the coating film may be a coating agent for forming a coated floor material by being applied to an object to be coated.

Examples of the paint include polyurethane resin paint, acrylic resin paint, unsaturated polyester resin paint, epoxy resin paint, nitrocellulose lacquer, acrylic lacquer, acrylic silicone resin paint, fluorine-containing resin paint, and sake varnish. The paint may be any of an organic solvent type, a non-solvent type, an aqueous solution type, an aqueous emulsion type, an aqueous dispersion type and the like. Among them, as the organic solvent-based paint, for example, organic solvents such as ethyl acetate, butyl acetate, methanol, ethanol, isopropyl alcohol, and mineral spirit can be used. The form of the paint may be liquid or powder. In addition, room temperature curable paint, heat curable paint or UV curable paint, EB
Any of the cured paints may be used.

The floor polish includes a polymer type using a polymer as a main raw material and a wax type using a wax as a main raw material. The form may be any of aqueous, emulsifying and oily. Commonly used flooring materials can be used, and examples thereof include epoxy resin systems, urethane resin systems, acrylic resin systems, MMA resin systems, and polyester resin systems.

The object to be coated refers to an object on which a coating film is formed, and is not particularly limited, and may be an organic compound, an inorganic compound, or a mixture thereof. Examples of the coating object of the organic compound include plastics such as polyvinyl chloride, polyethylene, polypropylene, PET, polystyrene, polyurethane, polyester, polycarbonate, ABS resin, and wood such as cedar, oak, toga, plug, rubber, and agathis. And their plywood and glulam. Examples of the inorganic compound to be coated include iron, stainless steel,
Metals such as brass and aluminum, ceramics such as porcelain and ceramics, stones such as marble and granite, glass,
Concrete, stone stone and the like.

Examples of objects to be coated include building materials such as floor materials and wall materials, and furniture members such as tables, chairs and counters. It is preferable that the object to be coated is a flooring material. Since the flooring material has a large area, the effect of the present invention that the coating film can be removed easily and in a short time can be effectively exhibited. The flooring may be in any form and state, and may be of any material commonly used for flooring. For example, i) resin-based material, ii)
Wood-based materials, iii) ceramic-based materials, iv) stones,
v) Applicable to floor materials such as concrete materials.

I) Floor material of resin-based material: Examples of the resin-based material include vinyl chloride. Examples of flooring made of this material include vinyl floor tiles such as composition vinyl floor tiles, homogeneous vinyl floor tiles, foam floor sheets such as cushion floors, woven laminated vinyl floor sheets, and nonwoven laminated vinyl floor sheets. Floor tiles made of natural materials such as sheets, linoleum flooring, cork tiles, and rubber tiles can be used.

Ii) Flooring of wood-based material: Examples of flooring of wood-based material include flooring, and specifically, single-layer flooring, composite flooring, flooring board, flooring block, mosaic parquet, soundproof floor , Sound insulation double floor, free access floor, etc.

Iii) Floor material of ceramic material: Examples of the floor material of ceramic material include porcelain tiles, ceramic tiles, ceramic blocks, and non-slip tiles.

Iv) Stones: Examples of the stones include marble, granite, and terrazzo. Examples of terrazzo include resin terrazzo and cement terrazzo.

V) Concrete-based flooring material: Concrete-based materials include, for example, mortar.

In particular, in a store, a hospital, a residence, an office, and a gymnasium, the above floor material can be used as it is, but in many cases, a coating film is formed by paint or floor polish. Such floor material maintenance work can prevent floor surface deterioration and improve durability. However, if the paint is applied over a dirty paint film, the stain will penetrate into the paint film, and the stain cannot be removed even by washing. For this reason, the present invention exerts an excellent effect on floor maintenance work since the removal efficiency of the coating film is high.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for removing a coating film according to an embodiment of the present invention will be specifically described with reference to examples.
In this example, various coatings were formed on the flooring material and removed by various methods. The removal rate of each coating film and the deterioration such as damage, swelling, dissolution, and decomposition of the coated object were visually evaluated. The percentages shown in the preparation of the coating solution and the release agent are as follows:
All are% by weight.

Example 1 An aqueous polyurethane resin (Neoletz R972 solid content 34
%: Avisia Co., Ltd.) was diluted with tap water to a solid content of 20% to prepare a coating solution for a coating film. This coating solution forms a coating film that can be dissolved in a vinyl floor release agent (Frontier Z Co., Ltd., Pomy Corporation) diluted twice with tap water. This coating solution was applied to a vinyl floor tile as an object to be coated by a roller (6 inches of blue sky: manufactured by Otsuka Brush) so that the film thickness after curing was 5 μm. Vinyl floor tiles are manufactured by Inlaid Elde (Takiron Co., Ltd.)
Made). The solution was allowed to stand at room temperature for 1 hour to evaporate the solvent and harden to form a coating film soluble in the release agent.

Further, an aqueous UV-curable resin (Lalomer L)
R8895 (50% solids) was diluted to 30% solids with tap water, and 2% of a photoinitiator Darocure 1173 (manufactured by Ciba Specialty Chemicals) was added.
A coating solution was used. This was applied with the same roller as above so that the film thickness after curing became 15 μm, and left at room temperature for 1 hour to evaporate the solvent. Furthermore, a high-pressure mercury lamp (H05-L2
1; manufactured by Eye Graphic Co., Ltd.) using 420 mj / cm
² was irradiated. As a result, as shown in FIG. 1A, a coating film 1 consisting of a surface aqueous UV-curable resin layer and a lower release agent-soluble layer was formed on the surface of the article 5 to be coated.

As shown in FIG. 1 (b), after the abrasive 2 made of alumina having a particle size of P120 is evenly spread on the surface of the coating film 1, as shown in FIG. The abrasive 2 was pressed against the coating film 1 by the pressing surface 77. The pressurizing body 7 is a substantially rod-shaped body having a length of 30 cm and a width of 10 cm.
A part of the side surface is a pressing surface 77. As shown in FIG. 3, the pressing surface 77 of the pressing body 7 is a curved surface that is smoothly curved in the moving direction.

As shown in FIG. 2D, the pressing body 7 was repeatedly moved 40 times at a speed of 30 cm / sec on the abrasive 2 to press the abrasive 2 against the surface of the coating film 1 a plurality of times. As a result, as shown in FIG. 2E, the coating film 1 was crushed into a crushed coating film 15. Most of the crushed paint film 15
Of the crushed pieces 10, and the coating film 1 remained in the lower layer. In the remaining coating film 1, a concave portion 11 was formed along the shape of the granular abrasive 2, and a crack 12 was formed around the concave portion.

Next, as shown in FIG.
The crushed pieces 10 of the coating film 1 were removed by suction with a vacuum cleaner. At this stage, it was confirmed visually that a part of the coating film 1 was removed. Thereafter, as shown in FIG. 2 (g), the above-mentioned release agent 3 for vinyl floor was applied to the surface of
After an hour, the release agent 3 and the coating film 1 were washed away with water and removed. The release agent 3 has a property of not damaging or dissolving the vinyl floor tile to be coated.

In this case, as shown in Table 1, the removal rate of the coating film was 100%, and no deterioration of the object was observed.
No damage such as abrasion was observed on the surface of the object 5 to be coated. The release agent used in this example is different from the conventional one in that it does not damage or dissolve the vinyl floor tiles to be coated. Such release agents have relatively weak intrinsic dissolving power of the coating film. However, as shown in FIG.
After pressing the coating 1, the thickness of the crushed pieces decreases,
Moreover, since the cracks 12 are formed in the surface, the release agent 3 is in a state of easily penetrating into the inside of the coating film. Therefore, it is considered that the remaining coating film could be easily and completely removed even when the relatively weak release agent 1 was used.

Example 2 The aqueous polyurethane resin used in Example 1 was used at a solid content of 20%.
% And diluted with tap water to prepare a coating solution.
The coating solution was applied to the same vinyl floor tile as in Example 1 so that the thickness after curing became 5 μm. The solution was left at room temperature for 1 hour to evaporate the solvent to form a release agent-soluble layer. Furthermore, an organic solvent-based acrylic resin paint (KC-10: manufactured by Gengen Chemical Industry Co., Ltd.) was applied by the same roller so that the thickness after curing was 15 μm. It was left at room temperature for 24 hours. Abrasive paper (F sheet, particle size: P120, manufactured by Kovacs Co., Ltd.) having an alumina abrasive having a particle size of P120 adhered to the coating film. From above, the abrasive paper was pressed against the coating film by a pressing body.

As shown in FIG. 4, the pressurizing body 70 has a rotating base 6 attached to the bottom 72 of a polisher body 71. A polisher is a machine that rotates a brush or a plastic scourer to clean the floor, and is generally used by building maintenance companies and cleaning companies.
Commercial products sold by Pomy Corporation, Zao Sangyo Co., Ltd., Penguin Wax Co., Ltd., Konishi Co., Ltd., etc. are used. The pressurizing body 70 of this example utilizes the polisher body 71. A steering handle 75 is attached to the polisher body 71.

As shown in FIG. 5, the rotary pedestal 6 is disk-shaped and has a mounting hole 61 at the center thereof. The rotating pedestal 6 has four casters 66 having rotating wheels 65 fixed thereto. The rotating wheel 65 is a sphere and is attached to a caster 66 so as to rotate in all directions without any trouble. The lowermost part of the rotating wheel 65 is a pressing surface 67 for pressing the abrasive. A mounting bracket 62 is provided on the rotating pedestal 6. Drive disk 73 of polisher body 71
The mounting hole 61 is inserted and fitted into the mounting bracket 62. The drive disk 73 is rotated by a motor provided inside the polisher body 71. The rotation of the driving disk 73 causes the rotating pedestal 6 to rotate.

The rotary pedestal 6 is formed by processing a plywood having a thickness of 18 mm. A caster 66 having a rotating wheel 65 whose rotating base 6 has a diameter of 30 cm is provided with a fixing screw 661.
To fix to the rotating base 6. The diameter of the rotating wheel 65 is 2.
5 cm. The rotation speed of the rotating base 6 is 200 rpm
It is. The moving speed of the pressing body 70 was 1 m ² per 2 minutes.

As described above, a part of the coating film was crushed to form crushed pieces. The remaining coating film had a recess along the shape of the abrasive and had cracks. Next, the abrasive paper was removed, and the crushed pieces of the coating film were removed by suction with a vacuum cleaner. Next, on the surface of the remaining coating,
The same release agent as in Example 1 was applied. In this case, as shown in Table 1, the removal rate of the coating film was 100%. No scratches, deterioration, or dissolution of the coated object were observed.

Comparative Example 1 A strong solvent-type release agent (manufactured by Skeleton Natco) was applied to the surface of the floor tile prepared in Example 1 at a rate of 100 g / m ² and left at room temperature for 2 hours. The surface was rinsed with water. In this case, as shown in Table 1, the removal rate of the coating film was 100%, but the surface of the object was dissolved.

Comparative Example 2 The release agent (Frontier Z) for vinyl floors used in Example 1 was directly applied to the surface of the floor tile prepared in Example 1 and left for 2 hours. Thereafter, the surface was rinsed with water.
In this case, as shown in Table 1, the surface of the object to be coated was not deteriorated, but the removal rate of the coating film was 0%.

Comparative Example 3 The surface of the floor tile prepared in Example 1 was shaved using abrasive paper (F sheet particle size: P120, manufactured by Kovacs Co., Ltd.). As a result, grinding fragments of the coating film were generated, and a part of the coating film remained below. Next, the abrasive paper was removed, and the crushed pieces of the coating film were removed with a vacuum cleaner. Tap water on the surface of the remaining coating film 2
A double-dilution vinyl floor release agent (Frontier Z) was applied to the surface of the polishing paper as it was. After leaving for 2 hours, the abrasive paper was removed. In this case, as shown in Table 1, the removal rate of the coating film was 80%, and many polishing scratches remained on the surface of the object to be coated.

[0046]

[Table 1]

[0047]

According to the present invention, it is possible to provide a method for removing a coating film in which a coating film can be easily peeled off in a short time while suppressing damage and deterioration of an object to be coated.

[Brief description of the drawings]

FIGS. 1A to 1C are diagrams illustrating a method of removing a coating film in Example 1. FIG.

FIGS. 2 (d) to 2 (g) show a method of removing a coating film following FIG.

FIG. 3 is a perspective view of a pressing body according to the first embodiment.

FIG. 4A is a front view of a pressing body and FIG. 4B is a plan view of a pedestal mounting portion in a second embodiment.

5A and 5B are a plan view and a side view, respectively, of a rotary base according to a second embodiment.

[Explanation of symbols]

 1. . . Coating film, 10. . . Crushed pieces, 2. . . Abrasive, 3. . . Release agent, 5. . . Coating object, 6. . . Rotating pedestal, 61. . . Mounting holes, 62. . . Mounting bracket, 65. . . Rotating wheel, 66. . . Casters, 67, 77. . . Pressing surface, 7, 70. . . Pressurized body, 71. . . Polisher body, 72. . . Bottom, 73. . . Drive disk, 75. . . handle,

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) C09D 9/02 C09D 9/02

Claims (9)

[Claims] In a method for removing a coating film from the surface of a coating object, an abrasive is supplied to the surface of the coating film, and the abrasive is pressed against the surface of the coating film by a pressing surface of a pressing body. A method for removing a coating film, comprising: crushing a film to form a crushed coating film; and removing the abrasive and the crushed coating film. 2. A method according to claim 1, wherein a release agent is applied to the surface of the crushed coating film. 3. The method according to claim 2, wherein at least the lowermost layer in the coating has a property of dissolving in the release agent. 4. The method according to claim 1, wherein:
The method for removing a coating film, wherein the pressing surface of the pressing body is a curved surface. 5. The method according to claim 1, wherein:
The method for removing a coating film, wherein the pressing body is a rotating wheel that rotates freely. 6. The method according to claim 5, wherein the rotating wheel is mounted on a rotating base that rotates. 7. The method according to claim 1, wherein:
The method for removing a coating film, wherein the pressing surface of the pressing body is a curved surface curved in a moving direction. 8. The method according to claim 1, wherein:
The method of removing a coating film, wherein the pressing surface of the pressing body is pressed a plurality of times against the surface of the coating film to which the abrasive has been supplied. 9. The method according to claim 1, wherein:
The method for removing a coating film, wherein the object to be coated is a floor material.