JPH078857A - Coating masking film roll using tubular film inner surface of which is treated with corona discharge - Google Patents

Abstract

PURPOSE:To produce a roll with ease and at low cost and also to improve the handling and quality of it by applying corona discharge treatment to the inner surface of a film and cutting open the film to fold it down before sticking an adhesive tape on the corona discharge treated surface and winding the film around a tubular body. CONSTITUTION:When a roll is produced, first a tubular film 2 is produced from a polyolefin based resin by an inflation. Next, a space of 1-7mm is left without the inner surfaces of the film 2 which seals in gas in a travelling state being stuck on each other, and an electrode is brought into contact with the outer surface of the film 2 in a state in which gas exists between the inner surfaces of the film 2, and corona discharge treatment is applied between the inner surfaces of the films 2 to improve the wet tension. Successively, a slit is made in the film 2 in the longitudinal direction, and the film 2 is folded in the longitudinal direction, and also the film 2 is rotated to expose the inner surface of the film 2. And after an adhesive tape 3 is stuck on the corona discharge treated surface (a), the film 2 is wound around a tubular body 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a masking film roll body for painting and a method for producing the same. Specifically, the coating masking film roll body of the present invention uses a film obtained by subjecting the inner surface of a tubular film to corona discharge treatment, and is used for buildings, roads, airfields, playgrounds, floors,
It is widely used for painting walls, automobiles, ships, airplanes, vehicles, machines, office supplies, sports equipment, amusement goods, leisure goods, various displays, toys, woodworking goods, household goods, etc.

[0002]

2. Description of the Related Art Various buildings, roads, playgrounds, parking lots, automobiles, vehicles, various articles and the like are coated with various paints in order to give them a beautiful appearance and to display marks, rules and explanations. In this case, in order to easily separate the painted part and the unpainted part, the unpainted part is covered with paper, synthetic paper, non-woven fabric, plastic film, etc., and the paint directly adheres to the surface or the paint moves from the painted part. Even if it adheres, it does not come into direct contact with the unpainted part, but it is received on the surface of paper, synthetic paper, non-woven fabric, plastic film, etc., and the unpainted part is shielded and protected from the paint. The film of paper or the like that fulfills this function is called a masking film for painting. There are various types of masking films for coating, depending on the shape of the object to be coated, the coating area, the performance of the coating material used, the baking temperature of the coating material, the drying temperature, etc. The coating masking film to be provided in the present invention is intended for coating with a relatively large coating area or non-coating area (that is, masking area),
The non-painted part (masking part) does not need to have a function of adhering or temporarily adhering the film to the non-painted part. When paint adheres to the film surface, the paint is likely to adhere, it is difficult to flow, and the adhered paint dries. Even when it is done, it is necessary to have the property of not peeling from the film surface. Paper, polyolefin, etc. have conventionally been used as the most masking material of this type in terms of price and performance, but paper is flexible, water resistant, solvent resistant, easy to handle, transparent, and mechanical. Since it lacks sufficient mechanical strength, the proportion of polyolefin films that do not have defects such as paper is increasing. A typical method for producing a conventional masking film for painting using a polyolefin film has a density of 0.94, for example.
~ 0.97 g / ml, melt index 0.05 ~
0.8 g / 10 min, high-density polyethylene having a melt tension of 5 g or more, extrusion temperature 170 to 210 ° C., frost line 20
A film is formed by an inflation method with a blow ratio of 0 to 800 mm and a draw ratio of 1 to 5 and is taken at a take-up speed of 10 to 200 m / min to obtain a tubular film having a thickness of 5 to 20 μm.
During sequential conveyance in the longitudinal direction, a thin blade metal cutter is applied to one location of the film to make a cut in the longitudinal direction of the film, and then the film is flattened by a roll, and the cut portion of the film is placed at the right end of the film or Rotate 180 degrees with the longitudinal direction of the left end as the axis of rotation so that the inner surface of the film is the front side, and stick the adhesive tape in the longitudinal direction of the film end so that part of it overlaps, and roll it around a paper tube. Consists of. However, since the coating masking film produced in this way has an inactive surface, it is difficult for the paint components to adhere to the surface, and especially when it is used by sticking it on a vertical surface, the paint component flows on the film surface and falls. However, the floor surface is polluted and the working environment is deteriorated.In addition, the paint components adhering to the film surface are easily peeled off from the film surface after drying, and they are detached from the film, and the dry paint is scattered on the surrounding floor surface. Undesirably worsens. On the other hand, as a conventional masking film for coating, if a flat polyolefin film is subjected to corona discharge treatment, the affinity of the treated surface with the paint will increase, and the paint components will easily adhere to the film surface and will not fall off easily. This is disclosed in Japanese Patent Laid-Open No. 3-42066. Since the corona discharge treatment is applied to the above-mentioned coating masking film made of only the polyolefin tubular film, it has the above-mentioned effects and is commercialized. However, as described in Example 1 of the above publication, "the tubular film is flattened with a pinch roll,
Immediately before being wound by a take-up roll, corona discharge treatment was performed in air from both sides, and the roll was taken up. The corona discharge treatment conditions are as follows. Corona discharger: H by Kasuga Denki
FSS-101, electrode-film gap: 2-3 mm ”, which is a conventional method of corona discharge treatment on a polyolefin tubular film, and only the outer surface of the tubular film is corona discharge treated. Indicates that the inner surface has not been treated at all. Then, the present inventor manufactured the masking film for coating by the method disclosed in the above-mentioned Japanese Patent Laid-Open No. 3-42066, and obtained the following knowledge about the problems in the manufacturing and the problems concerning the product. First, in the method of the above invention,
The tubular film is made flat, and the corona discharge treatment is performed on the outer surface of the tubular film, and the tubular film is cut open to form a flat film. A part of the pressure-sensitive adhesive layer of the adhesive tape with a width of 15 mm (width about 4 mm) Adhesive tape is laminated between the rolls so that it overlaps with the corona discharge treated surface.The product form is not folded in the width direction.In the case of a narrow coating masking film, roll it as it is. However, there are no bulky drawbacks, but there is little demand for such narrow width products, and there is a large width of 20 to 2 for those with large demand.
It is a masking film for painting of 50 cm. Further, when a wide product is manufactured by the method disclosed in Japanese Patent Laid-Open No. 3-42066, since the roll is wound in a wide width as it is, the width of the product is wide, the storage space of the product is large, and the coated surface is covered with a masking film. It is also difficult to attach the pressure-sensitive adhesive layer portion, and it is also difficult to manually tear off the masking film except the required area after the attachment. In order to solve this problem, it is possible to fold the films in parallel to the longitudinal direction and stack the films in multiple layers instead of keeping the wide width, so that the wide defects were solved. , The adhesive surface side of the adhesive tape and the corona discharge treated surface side of the masking film located at the end portion in the width direction when viewed from the adhered portion of the adhesive tape are located on the same plane, although they are displaced by several centimeters. Because
When the coating masking film is pulled out from the roll and attached to an object to be coated, the corona discharge-treated film edge is caught in the adhesive surface of the adhesive tape, which makes the above operation very difficult. In order to avoid this, after the corona discharge treatment on the outer surface of the tubular film, the tubular film is cut open, the inside and outside of the film are reversed, the inside is the corona discharge treated surface, and the outside is the non-corona discharge treated. As a surface, by folding the film in the same manner as the above in the longitudinal direction and sticking the adhesive tape to the end of the film on the corona discharge surface, the adhesive layer surface of the adhesive tape and the opposite end of the masking film Since the non-corona discharge surface of the film can be located on the opposite side of the adhesive tape from the adhesive layer surface without the non-corona discharge surface being located close to the same plane, a masking film can be applied. When applied to a surface, the edges of the film are not rolled up at all.

[0003]

DISCLOSURE OF THE INVENTION As described above, a compact masking film roll body for painting, which is made of polyolefin, forms a tubular film, corona discharges it on its surface, and cuts the tubular film open. , Reverse the inside and the outside, fold the film in multiple layers parallel to the longitudinal direction of the tubular film, parallel to the longitudinal direction at one end of the film, and so that the adhesive layer faces the corona discharge treated surface, Although it has been developed to the point where it can be manufactured by applying an adhesive tape, the product obtained by the above method has sufficient performance, but it is very difficult to manufacture, and the product for painting manufactured by such a method is used. Masking film rolls have not been commercialized. In view of the above circumstances, the present invention provides a method for producing a masking film roll body for painting, which does not take up space and is easy to attach to a coated surface, at a reasonable cost, and a method thereof. An object is to provide a masking film roll body for painting that is manufactured.

[0004]

That is, the present invention is a process 1 for producing a tubular film from a polyolefin resin by an inflation method, without adhering the inner surface of the running tubular film in which gas is enclosed. With a gap of 1 to 7 mm, in the presence of gas between the films, at least a pair of electrodes to which a high-voltage current is applied is brought into contact with the outer surface of the film, and corona discharge treatment is applied between the inner surfaces of the film. Step 2 of improving the wetting tension, Step 3 of sequentially conveying the tubular film after corona discharge treatment in the longitudinal direction, and making Step 3 of the film in the longitudinal direction of the film, Parallel to the longitudinal direction of the tubular film Folding the film into the lengthwise direction of the film cut in Steps 4 and 3 Step 5 of exposing the inner surface of the film by rotating it 180 degrees about the longitudinal direction at the end of the film as a rotation axis, and at the left end or the right end of the corona discharge treated surface, an adhesive tape and an adhesive layer of the adhesive tape and a corona discharge treated surface. A tubular film comprising steps 6 and 7 in which the adhesive tape-bonded film obtained in step 6 is wound around a tubular body, The present invention relates to a method for producing a masking film roll body for painting, which comprises using a film having an inner surface subjected to corona discharge treatment. In a preferred embodiment of the above-mentioned production method of the present invention, step 6 comprises a width of 3 to 20 on the surface having a width of 1 to 10 mm from the left end or the right end in the longitudinal direction of the film.
2 to 15 mm in width on the right or left side of the adhesive tape of 2 mm, and the width 2 to 19 on the left or right end.
mm adhesive tape is left unbonded. Further, the present invention is produced by the above method, one end in the longitudinal direction of the wide film is positioned with the corona discharge treated surface as the front side, and the one end of the adhesive tape has a part of the adhesive layer surface corona. The film that has been pasted to face the discharge-treated surface and is continuously present at one end of the film is corona-discharge-treated and is folded back around the longitudinal center in the longitudinal direction as a rotation axis, and the folded back film portion. Has the corona discharge treated surface as the back side, one end of the above film and the film portion existing continuously therewith, and the corona discharge treated surface faces each other, and the overlapped film portion is gusseted at least once. Or, it is subjected to rotational folding with the longitudinal direction as the axis of rotation, and the pressure-sensitive adhesive layer surface of the pressure-sensitive adhesive tape and the non-corona discharge treated surface of the folded film are in mutual contact. A thick single that is located toward the back on,
The present invention relates to a masking film roll body for painting, which comprises a film wound on a tubular body in a direction perpendicular to the longitudinal direction of the film and whose inner surface is subjected to corona discharge treatment. A preferred embodiment of the masking film roll body for coating of the present invention is such that a film portion having a width of 2 to 20 mm on the left side, which is a part of a wide film, is positioned with the corona discharge treated surface on the front side, and the left side thereof is adhesive. The tape is attached such that a part of the right side of the pressure-sensitive adhesive layer surface faces the corona discharge treated surface, and the width is 2 to 20.
a corona discharge treated width of 10 to 1 which is present as a part of a wide film on the right side of the film portion of mm.
A film of 00 cm was folded back in the vicinity of the center in the width direction with the longitudinal direction as a rotation axis, and the folded back portion of the film having a width of 5 to 70 cm had the corona discharge treated surface as the back side, which was one of the width of the film portion having a width of 2 to 20 mm. Part and a film part which is continuous to the right side of the film part and are present as a part of the wide film, and the corona discharge treated surfaces are overlapped with each other, and the overlapped film parts are gusseted or elongated at least once. The rotation is performed with the direction of rotation as a rotation axis, and the pressure-sensitive adhesive layer surface of the pressure-sensitive adhesive tape and the non-corona discharge treated surface of the folded back film having a width of 5 to 70 cm are arranged with their backs facing each other. Is wound around a tubular body in a direction perpendicular to the longitudinal direction of the film. In the above preferred embodiment, the tubular film is cleaved, and only the case where the film is rotated to the left side is described, but this is so as not to misunderstand the technical content, and of course, it is, of course, It goes without saying that when the film is rotated to the right, a product having the same effect as when rotating the film to the left can be obtained.

In the present invention, the polyolefin resin means high-density polyethylene, medium-density polyethylene, high-pressure low-density polyethylene, linear low-density ethylene-α-olefin copolymer, ethylene-vinyl acetate copolymer, ethylene- Examples include acrylic acid ester copolymers,
High-density polyethylene is particularly preferable because of its strength, cross-cutting property, handleability, workability, heat resistance and the like.

In the process 1 for producing a tubular film by the inflation method in the present invention, a polyolefin resin is extruded from a circular die at a temperature above its melting temperature, air is introduced into the tubular film, and air cooling or water cooling is performed. Done. The conditions of the above operation are appropriately selected, but the resulting tubular film preferably has a thickness of 5 to 20 μm.

In the step 2 of the present invention, a gap of 1 to 7 mm is provided without adhering the inner surface of the running tubular film in which a gas is enclosed, and a gas is present between the films. Is contacted with at least a pair of electrodes to which a high voltage current is applied, and corona discharge treatment is applied between the inner surfaces of the film to improve the wetting tension of the inner surface of the film.
It is performed by the method disclosed in Japanese Patent Publication No. 24412. Although the technology disclosed in the publication relates to a tubular film whose inner surface is corona-discharged, its application is that, when the meat is filled, it only mentions the meat filling effect that the meat adheres to the inner surface of the film. There is no suggestion that it can be used for the application of the masking film for coating as in the invention.

In the step 2, the tubular film after corona discharge is sequentially conveyed in the longitudinal direction, and a slit is made in the longitudinal direction of the film by applying a thin blade metal cutter, a laser beam, a heat spot, etc. to one location of the film. According to 3, the tubular film can be made into a strip-shaped film.

In the present invention, in the step 4 of folding the film (strip-shaped film) cut in the step 3 in parallel with the longitudinal direction, the tubular film is crushed as it is, and when a part of the tubular film is cut into a product, it is widened. This is not desirable because it makes the product unusable, the storage space becomes large, and the masking work for painting becomes difficult. Therefore, it is necessary to make the product compact. The folding method may be any of gusset folding, multiple folding and the like, but it is necessary that the adhesive surface of the adhesive tape and the portion of the masking film on the opposite side of the adhesive tape are not flush with each other. This is because if they are flush with each other, part of the masking film will be wrapped around the adhesive tape and the painted surface when the adhesive tape portion is attached to the painted surface, and the work will have to be redone.
The folding step 4 may be performed immediately after step 3 or after step 5 or 6.

In step 3, the left or right portion of the film cut in the longitudinal direction is rotated 180 degrees about the longitudinal direction at the end of the film as the axis of rotation to expose the inner surface of the film. The inner surface of the processed film is exposed on the front side, and the adhesive tape can be attached to the end of the film.

In the present invention, at the left end or right end of the corona discharge treated surface, an adhesive tape is made to face the adhesive layer of the adhesive tape and the corona discharge treated surface, and an unbonded portion is left or right side of the adhesive tape. The process of bonding with leaving is to fix the adhesive tape for sticking a part of the masking film to the coating object with the corona discharge surface of the film as the front and the non-coated surface of the film as the back. It is necessary, and preferably the right or left side of the adhesive tape having a width of 3 to 20 mm is attached to the surface having a width of 1 to 10 mm from the left edge or the right edge of the film, and the adhesive layer portion having a width of 2 to 15 mm is attached to the left edge or the right edge. The adhesive tape with a width of 2 to 19 mm is left unbonded.

By the step 7 of the present invention in which the adhesive tape-bonded film obtained in step 6 is wrapped around a tubular body, the product can be rolled to make the product form compact. As the tubular body, a paper tube, a plastic tube, a metal tube, a wood tube or the like can be used, but a paper tube is preferable in terms of cost and performance.

[0013]

EXAMPLES Next, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. Production example of masking film for painting Density 0.948 g / ml, melt index 0.06
High-density polyethylene of g / 10 min was extruded from a die at 190 ° C., and a tubular film having a thickness of 10 μm and a folding diameter of 25 cm was obtained by an air cooling inflation method under the conditions of a blow ratio of 4.5 and a winding speed of 50 m / min. . A gap of 2 mm on the inner surface of the film was used, air was used as a gas enclosed in the film, and a corona discharge treatment was performed using a film inner surface corona discharge treatment machine (manufactured by Kasuga Denki) so that the wetting tension of the inner surface of the film was 45 dyne / cm. Nearly the center of the tubular film (as a flat film, the folding diameter is 25 cm,
At a position 10 cm from the left end of the film), make a slit in parallel with the longitudinal direction with a thin razor blade, and then 180 ° to the upper film piece of the flat film existing to the left of the slit with the left end of the flat film as a rotation axis. It was rotated to expose the corona discharge treated surface of the film piece. Affix a part of the adhesive layer (width 5 mm) of the adhesive tape with a width of 15 mm (width 5 mm) along the longitudinal direction of the film on the left end of the corona discharge treated surface of the film piece 5 mm so that it faces the corona discharge treated surface. It was On the other hand, parts other than the above-mentioned film pieces of the flat film were made into a six-layer film by repeating Gazette folding and double folding, and the bottom film layer was folded so as to be located on the side opposite to the pressure-sensitive adhesive layer surface of the pressure-sensitive adhesive film. . The thick piece prepared as above has a diameter of 2 cm and a length of 12 cm.
The paper tube was rolled to a diameter of 7 cm to obtain a masking film roll for painting. The state in which the end of the obtained roll body is pulled out is shown in FIG. In the figure, 1 is a paper tube, 2 is a film, and 3 is an adhesive tape, and a, b and c are a corona discharge treated surface, a non-corona discharge treated surface and an adhesive layer, respectively. Evaluation results a. Handleability: The film was unwound from the roll body, a wooden board was placed vertically, the adhesive tape portion was horizontally attached to a length of 30 cm, and the film was cut by hand. Roll is 12 cm wide
The length of the folded film is 7 cm in the palm of your hand, and the folded film hangs down by gravity on a flat film.
The handleability was very good. b. Adhesion of paint: A red acrylic paint was applied to the surface of the film in an amount of 20 μm (thickness when dried), but it was evenly applied to the surface and did not drip. Further, after the coated surface was dried, the masking film was peeled off, but the dried paint did not peel off from the film. Furthermore, the film to which the paint after drying adhered was touched by hand, but the paint did not come off.

[0014]

INDUSTRIAL APPLICABILITY As described in detail above, in the production of the masking film roll body for coating according to the present invention, the inner surface of the polyolefin resin tubular film is first subjected to continuous corona discharge treatment to cut open the tubular film. , Folding in a specific manner in the longitudinal direction, sticking an adhesive tape on one end of the film facing the corona discharge treatment surface, rolling it on a tubular body, and performing these in a continuous line process, Compared with the method, the manufacturing is easier and the manufacturing cost can be reduced. Further, the obtained coating masking film roll body has a structure different from that of the conventional one, and the coating material is easily adhered, does not flow, and the coating material does not peel off after drying. Moreover, it is very excellent in handling and workability, and the storage space can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view of a coating masking film roll body obtained in an example of the present invention.

[Explanation of Codes] 1 Paper tube 2 Film 3 Adhesive tape a Corona discharge treated surface b Non-corona discharge treated surface c Adhesive layer

Claims (2)

[Claims] 1. A process 1 for producing a tubular film from a polyolefin-based resin by an inflation method, wherein a gap of 1 to 7 mm is provided without adhering the inner surface of the running tubular film in which a gas is enclosed, to form a film. Step 2 for improving the wetting tension of the inner surface of the film by contacting at least a pair of electrodes to which high voltage current is applied to the outer surface of the film in the state where gas is present, and performing corona discharge treatment between the inner surfaces of the film, corona discharge While sequentially transporting the treated tubular film in the longitudinal direction, a step 3 is made in which a cut is made in one part of the film in the longitudinal direction, a step 4 in which the tubular film is folded parallel to the longitudinal direction, and a break is made in step 3. Rotate the left or right part in the longitudinal direction of the inserted film at the edge of the film. Step 5 of exposing the inner surface of the film by rotating as 180 degrees, the adhesive tape is placed on the left end or the right end of the corona discharge treated surface so that the adhesive layer of the adhesive tape faces the corona discharge treated surface, and the left side or the right side of the adhesive tape Step 6 in which the unbonded portion is left unbonded, Step 7 in which the adhesive tape-bonded film obtained in Step 6 is wrapped around the tubular body, and a film whose inner surface is treated with corona discharge is used. A method for producing a masking film roll body for painting, characterized by: 2. The wide film produced by the method according to claim 1 has one end in the longitudinal direction positioned with the corona discharge treated surface as the front side, and the one end is provided with an adhesive tape on one side of the adhesive layer surface. The part is laminated facing the corona discharge treated surface, and the corona discharge treated film continuously existing at one end of the film is folded back around the longitudinal center around the longitudinal axis as a rotation axis, and folded back. The corona discharge treated surface is the back side of the film portion, and the corona discharge treated surface is overlapped with one end of the film and the film portion that is present continuously with the film portion. Rolled gusset folds or rotation folds with the longitudinal axis as the axis of rotation, and the adhesive layer surface of the adhesive tape and the non-corona discharge treated surface of the folded back film. Is a coating characterized by using a film whose inner surface is corona-discharge-treated, which is formed by rolling a single piece that is arranged with their backs to each other and is wound around a tubular body in a direction perpendicular to the longitudinal direction of the film. Masking film roll body.