JP2000096008A - Masking tape for coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a masking tape for coating capable of finishing parting lines attractively and beautifully and releasable without tape torn and easily when detaching the masking tape from a coating matter at a low temperature. SOLUTION: This masking tape for coating comprises a substrate 1 and an adhesive layer 3, the substrate consists of a synthetic resin and having at least one layer of substrate auxiliary layer 2 at one or both sides of the substrate consisting of the same or another synthetic resin material of the substrate. The elastic modulus of the synthetic resin material composing the substrate auxiliary layer is preferably smaller than that of the substrate at 0-40 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a masking tape for coating which is used for concealing an area of the object to be coated which does not require coating in a coating operation. More specifically, the coating masking tape of the present invention reduces the step (also referred to as "parting step") at the boundary between the painted part and the unpainted part when the masking tape is peeled off after completion of painting, and looks good at the parting line. It can be finished well and beautifully, and when the masking tape is peeled off from the object to be coated in a state where the temperature of the coating film has been lowered a little after the completion of painting, it can be easily peeled without causing tape breakage Is possible. The masking tape of the present invention can therefore be advantageously used in various painting operations.

[0002]

2. Description of the Related Art Conventionally, various kinds of masking tapes have been used in coating an automobile body or the like in order to temporarily cover an area of the object to be coated which does not require coating. The coating masking tape is usually composed of a base material and an adhesive layer applied to one surface (to be coated) of the base material. The base material of the masking tape has good follow-up properties to coated objects with various shapes such as curved surfaces, no adhesive residue when peeling, no tape breakage, contamination to coated objects Many requirements are imposed, such as lack of properties, and that the cured paint does not peel off from the masking tape.Therefore, at present, papers such as crepe paper, kraft paper, Japanese paper, and olefin-based synthetic resins Synthetic resin films of vinyl chloride, polyester, nylon and the like are frequently used. Masking tapes using these materials as a base material have good follow-up properties to the object to be coated, but when peeled off from the object after the curing of the paint is complete, a partial However, there is a problem that the tape may be broken due to high stress concentration.

In order to avoid the problem of tape breakage, there is a method of increasing the mechanical strength by increasing the thickness of the tape, or a method of drying the coated object in a drying device (heat oven, etc.) after coating is completed. At the stage of providing the curing step, when the coating film is still in a high temperature state immediately after taking out the object to be coated from the drying device, that is, while the coating film is still soft, a method of manually peeling off the masking tape is known. Has been adopted. However, in the method of increasing the thickness of the tape, especially in the metallic coating, mica coating, etc., which are often introduced recently for the purpose of improving the appearance, due to the adoption of a coating method of applying several kinds of paints repeatedly, The step between the painted part and the unpainted part becomes large, and it is easy to damage the step (the end of the painted part) during the work of peeling off the masking tape. Also, the painted part becomes thicker, so that a good-looking appearance can be obtained. Can not. Further, in this method, since the stiffness of the tape is increased, the followability is particularly poor in the curved surface portion, and a small gap is generated between the object to be coated and the tape, so that the unpainted portion cannot be concealed sufficiently.

In the method in which the masking tape is manually peeled off immediately after the object to be coated is taken out of the drying apparatus, the coating film is extremely hot, so that the operator is not burned. Safety considerations, such as Nikko, are indispensable. In addition, if there is a noticeable step at the end of the obtained coating film, it is necessary to fill or grind the compound in order to make the step inconspicuous, which increases the man-hour and the cost. The increase cannot be avoided. In addition, when cleaning the object to be coated, there is a problem that a cleaning tool such as a brush is caught on a step portion and the painted surface is easily damaged.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to separate the boundary between a painted portion and a non-painted portion when the masking tape is peeled off after the painting is completed. The steps can be reduced to make the parting line look good and beautiful.Also, after a while after the completion of coating, when the masking tape is peeled off from the workpiece with the temperature of the coating film lowered, and others A masking tape for coating that can be easily peeled off from the object to be coated without causing tape breakage in a low temperature environment.

[0006]

According to the present invention, there is provided a masking tape for coating including a substrate and an adhesive layer, wherein the substrate is made of a synthetic resin material,
At least one layer of a base material auxiliary layer made of the same or different synthetic resin material as the base material is laminated on one or both surfaces of the base material, which can be achieved by a coating masking tape. .

In the masking tape for coating of the present invention, the base material auxiliary layer may be composed of a single layer, or may be composed of two or more layers. When the base material auxiliary layer is composed of a single layer, the base material auxiliary layer can be preferably laminated on one side of the base material having no pressure-sensitive adhesive layer. When the base material auxiliary layer is composed of two or more layers, those base material auxiliary layers are
It may be laminated on one side of the base material that does not have the adhesive layer, otherwise, some of the base material auxiliary layers are laminated in the middle of the base material and the adhesive layer. It may be.

[0008] The synthetic resin material constituting the base material auxiliary layer is 0
At -40 ° C, it is preferable to have a lower elastic modulus than the synthetic resin material constituting the base material, and more preferably, at 10 ° C, 1.0 × 10 ^{5 to} 1.0 × 10 ¹⁰ dy.
It has an elastic modulus of n / cm ² . Further, the thickness of the base material auxiliary layer is preferably about 1 to 100 μm. The thickness of the coating masking tape can be widely varied depending on the application site of the tape, the purpose of use, and the like, but is usually about 140 μm or less. The masking tape is preferably made as thin as possible in consideration of the finishing effect of the parting line.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION As described above, the masking tape for coating of the present invention comprises a base material and a pressure-sensitive adhesive layer, wherein the base material is made of a synthetic resin material and one side of the base material Alternatively, at least one base material auxiliary layer made of the same or different synthetic resin material as the base material is laminated on both surfaces. At a temperature of 0 to 40 ° C., the elastic modulus of the substrate auxiliary layer is smaller than the elastic modulus of the substrate.

In the masking tape for coating of the present invention, taking the case where the base material auxiliary layer is a single layer as an example, preferably, the base material 1 is coated on one side as shown in FIG. The pressure-sensitive adhesive layer 3, the base material auxiliary layer 2 laminated on one side of the base material having no pressure-sensitive adhesive layer, and the release treatment agent layer 4 further provided on the base material auxiliary layer Be composed.
Although not shown, the coating masking tape 10 may have additional layers that are common in the art, if necessary. Examples of the additional layer include an ink layer for coloring and an anchor coat layer for improving the adhesive strength between the layers. Hereinafter, each tape component will be described with reference to the masking tape of FIG.

The substrate 1 can be formed from any synthetic resin material. However, the synthetic resin material used here, however, has a wide range of shapes of the object to be coated, so that it has good followability to a curved surface portion, and high temperature conditions are applied to the drying and curing of the coating film. It is desirable to satisfy requirements such as being excellent, having an appropriate mechanical strength, and preventing the paint from penetrating. Suitable synthetic resin materials include:
Although not limited to those listed below, mention may be made of polyester resins, nylon resins, polyvinyl chloride resins, polyolefin resins such as polypropylene, and others.

The thickness of the substrate 1 is usually about 10 to 120 μm.
m, more preferably about 15 m.
It is in the range of ~ 100. If the thickness of the base material 1 is less than about 10 μm, the strength of the base material is too weak, so that the masking tape 10 may be torn. About 120
When the thickness exceeds μm, the total thickness of the tape becomes about 150 μm or more, and various inconveniences due to the increase in the level difference tend to occur.

The base material auxiliary layer 2 functions to eliminate the necessity of increasing the thickness of the base material in the masking tape 10 of the present invention by making the base material multi-layered and compounded, and particularly as a stress buffer layer. Can be achieved. That is, the presence of the base material auxiliary layer 2 adjacent to the base material 1 can prevent stress from concentrating on the base material and preventing tape breakage. The base material auxiliary layer 2 can be made of the same or different synthetic resin material as that of the base material 1, and preferably can be made of a different synthetic resin material in anticipation of a synergistic effect of the two. The synthetic resin material used here is soft,
It is desirable that the adhesiveness be excellent.

The synthetic resin material constituting the base material auxiliary layer 2 is as follows:
Preferably, 1.0 × 10 at 10 ° C. ^Five~ 1.0 × 10^Ten
dyn / cm^TwoHas the following elastic modulus. Elasticity of synthetic resin material
The rate is 1.0 × 10^Fivedyn / cm^TwoBelow the tape back
Slippage is worse, and the workability of tape application is reduced.
You. Also, when formed into a roll, the soft resin protrudes.
This increases the risk of the roll side sticking. Opposition
1.0 × 10^Tendyn / cm^TwoAbove, stress buffering
Is not enough and slivering occurs. What
Contact, "slivering" means the tape breaks when peeling
Therefore, the “slivering resistance effect”
This is an effect that can prevent cut-out.

The synthetic resin materials capable of satisfying the above requirements for the elastic modulus are not limited to those listed below, but include polyacrylate resin, SBR (styrene-butadiene rubber). Resin, NBR (acrylonitrile-butadiene rubber) resin, MBR (methacrylate-butadiene rubber) resin, urethane resin, polyolefin resin and the like. In addition, these materials may contain an organic filler such as organic glass beads and an inorganic filler such as a pigment for coloring, and can be crosslinked to improve solvent resistance.

Further, the thickness of the base material auxiliary layer 2 composed of the above-mentioned synthetic resin material is preferably about 1 to 5.
100 μm. The thickness of the base material auxiliary layer 2 is about 1 μm
When the thickness is less than about 100 mm, the slivering effect is lost, and when the thickness exceeds about 100 μm, the total thickness of the tape is about 150 μm.
It becomes about μm or more, which causes various inconveniences due to the increase in the level difference.

The lamination of the base material auxiliary layer 2 to the base material 1 can be carried out arbitrarily by using a technique commonly used in the field of film formation. Suitable lamination methods include, but are not limited to, those listed below:-a solution of the selected synthetic resin material in an organic solvent,
A method of applying to a film a method of applying an aqueous dispersion of a synthetic resin material synthesized by an emulsion polymerization method or the like; a method of liquefying a 100% solid resin by heat melting or the like to form a film. Coating method-a method in which a synthetic resin material as a base material is extruded at the same time as being formed into a film by extrusion or the like.

The pressure-sensitive adhesive layer 3 applied to one side of the substrate 1 for attaching a tape to an object to be coated can be satisfactorily adhered to a steel plate or the like which is a typical example of the object to be coated. It can be easily peeled off. Although not limited to this, it is preferable that the adhesive is selected from those which can be used several times by re-applying even after the tape is peeled off from the surface of the object to be coated. Such an adhesive may be referred to as a reposable adhesive. Further, the pressure-sensitive adhesive layer 3 can be formed of a pressure-sensitive adhesive that does not cause contamination of the object to be coated. The pressure-sensitive adhesive used here is not particularly limited, but is preferably one that is not attacked by the solvent in the paint.As a suitable pressure-sensitive adhesive, for example, an acrylic-based, natural rubber-based, synthetic rubber-based, urethane-based pressure-sensitive adhesive is used. Can be mentioned.

The pressure-sensitive adhesive layer 3 has a thickness of about 100 to 2 like the pressure-sensitive adhesive layer of a masking tape generally used in this technical field.
It preferably has an adhesive strength of 000 g / 25 mm, more preferably has an adhesive strength of about 200-1500 g / 25 mm, and most preferably has an adhesive strength of about 300-1000 g / 2.
Has an adhesive strength of 5 mm. The adhesive strength of the adhesive layer 3 is about 100
g / 25 mm, the masking tape cannot be strongly adhered to the object during the coating process. Conversely, if it exceeds about 2000 g / 25 mm, the bonding strength of the tape to the object is strong. Too much tape breakage during peeling.

The pressure-sensitive adhesive layer 3 has a thickness of about 4 to 4 in the same manner as the pressure-sensitive adhesive layer of a masking tape generally used in this technical field.
It may have a layer thickness of 70 μm, more preferably about 10 to 50 μm. If the pressure-sensitive adhesive layer 3 is thinner than about 4 μm, the desired adhesive effect cannot be obtained. Conversely, if the pressure-sensitive adhesive layer 3 is thicker than about 70 μm, the bonding strength of the tape to the object to be coated is too strong,
Tape breakage occurs during peeling.

The pressure-sensitive adhesive layer 3 is formed, for example, by using the same method as that used in the production of a general pressure-sensitive adhesive tape.
By using a knife coating method, a roll coating method, a gravure coating method, or the like, a film can be formed with the above-mentioned layer thickness. The masking tape 10 can have the release treatment agent layer 4 as its uppermost layer. The release treatment agent layer 4
As described above, this is for easily processing the masking tape 10 into a roll shape, and is arbitrarily formed from a common release agent such as a urethane-based release agent or a polyethylimine-based release agent. can do. The release agent used in the practice of the present invention is not particularly limited, but a non-silicone-based agent is preferably used.

The release agent layer 4 can have a layer thickness of about 0.001 to 0.1 μm, more preferably about 0 to 0.1 μm, like the release agent layer of a masking tape generally used in this technical field. It can have a layer thickness of from 0.01 to 0.05 μm. Release treatment agent layer 4 is about 0.001 μm
If the thickness is too thin, the intended peeling effect cannot be obtained, and handling of the tape becomes inconvenient.

The release agent layer 4 is formed by using a method similar to that used in the production of general adhesive tapes, for example, by using a spray coating method, a roll coating method, a gravure coating method, or the like. The film can be formed with the above-mentioned layer thickness. In addition, the release treatment agent layer 4 is not necessarily the substrate 1
It is not necessary to laminate to the base material auxiliary layer 2 or, for example,
A release treatment agent may be mixed into the base material auxiliary layer 2, or the base material support layer 2 itself may have a release treatment function.

A masking tape 10 comprising a base material 1, a base material auxiliary layer 2, an adhesive layer 3, and a release agent layer 4.
The thickness of the tape can vary widely depending on the application site of the tape, the purpose of use, etc.
20 μm or less. When the base material 1 is made of a polyester resin, the thickness of the base material can be reduced.
The range is 0 μm. The masking tape 10 is preferably made as thin as possible in consideration of the finishing effect of the parting line.

By using the coating masking tape of the present invention, various paints can be selectively applied to a substrate having various forms. For reference, liquid paints such as acrylic resin paints, urethane resin paints, alkyd resin paints, polyester resin paints, vinyl chloride paints, etc. Powder coatings corresponding to coatings are often used.

[0026]

The present invention will be described below in detail with reference to examples and comparative examples. In addition, Table 1 below describes the materials used as the base material of the masking tape in each example together with the trade name, product number, manufacturer, and thickness. In each of the examples, the material used as the base material auxiliary layer of the masking tape is described together with the trade name, product number, manufacturer, thickness, and elastic modulus. Here, the elastic modulus is
Rheometrics measuring device, Viscoelas Tic Mete
r Using RSA-II, deposit a sample on a liner
5. A sample having a thickness of 100 μm, a width of 8 mm, and a length of 35 mm was prepared.
It was determined by measuring the dynamic viscoelastic modulus at 28 rad / s. Example 1 A 25 μm-thick double-sided corona-discharged PET film, “Embret ^™ S” (trade name) manufactured by Unitika Ltd. was coated on one surface so that the thickness after drying was 5 μm.
An SBR latex resin having a modulus of elasticity of 2.2 × 10 ⁹ dyn / cm ² was coated with “Nipol ^™ ” manufactured by ZEON CORPORATION.
Dry at 00 ° C. for 3 minutes. SB formed
A urethane release agent was further thinly applied on the R latex resin layer and dried. Then, on the surface opposite to the surface coated with the SBR latex resin of the PET film, a pressure-sensitive adhesive obtained by blending a tackifier resin with natural rubber in a heptane solvent so that the thickness after drying becomes 25 μm. Coated. The obtained adhesive sheet was cut into strips having a width of 18 mm and a length of 30 mm to prepare test tapes.

The resulting test tape was evaluated for slivering, total tape thickness (μm), parting level, and flaking according to the following test guidelines. Slivering: Twenty test tapes were affixed to a melamine-coated plate, a melamine-coated steel plate manufactured by Nippon Tact Co., Ltd. and sufficiently pressed, and then spray-coated with a cross-linking paint used in an automobile coating line. To dry the paint sufficiently, put the melamine coated plate in a hot oven at 140 ° C,
Left for 20 minutes. After leaving the melamine coated plate removed from the heat oven at room temperature for 2 hours, each test tape was quickly pulled at a certain angle (45 °) and peeled off. 2
The number of the tapes that were cut during peeling out of the 0 test tapes was recorded, and this was defined as “slivering (number of tape cuts)”. In the case of this example, occurrence of slivering could not be recognized. The number of slivering is
The less it means the better the result. Total tape thickness: The total tape thickness was measured using a dial thickness gauge manufactured by Mitutoyo Corporation. The measured value in the case of this example was 55 μm, which was the same result under the manufacturing conditions. Parting step: One test tape was adhered to a melamine coated plate in the same manner as in the slivering test, a cross-linked paint was applied by spray coating, dried, and further quickly peeled off. After the tape was peeled off, the stepped portion of the parting line was traced with a finger, and the degree of catching with the finger was determined. "Low" means that there is little snagging and the step is felt sufficiently low.
"Medium" was given when a little bit was felt but the step was felt low, and "High" was given when the finger was strongly felt and the step was felt high. Flaking: The state of the scattered hardened paint shards after peeling off the tape is visually judged. If the paint remains 90% or more on the back of the tape, it is regarded as "good" and 90% on the back of the tape.
Those with the following paints remaining were rated "bad".

The results obtained are summarized in Table 3 below. Examples 2 to 20 Test tapes were prepared by repeating the procedure described in Example 1 above. In this example, the base material and the base material auxiliary layer were changed as shown in Tables 1 and 2 below, respectively.

The obtained test tape was evaluated for the same test items according to the procedure described in Example 1 above. The results summarized in Table 3 below were obtained. Examples 11 and 12 are examples in which the base material is multilayered. However, when the PE layer used in these examples is considered as the base material auxiliary layer, the thickness of the base material auxiliary layer is set to the value in the example. 11 at 5
5 μm, and 80 μm in Example 12. Comparative Examples 1 to 6 A test tape was produced by repeating the method described in Example 1 above. In this example, for comparison, the base material and the base material auxiliary layer were changed as shown in Tables 1 and 2 below, respectively.

The obtained test tape was evaluated for the same test items according to the procedure described in Example 1 above. The results summarized in Table 3 below were obtained.

[0031]

[Table 1]

[0032]

[Table 2]

[0033]

[Table 3]

From the results shown in Table 3 above, the following points are considered. First, a test tape manufactured in accordance with the present invention, that is, a masking tape for coating, has a base material made of a synthetic resin material with an elastic modulus of 1.0 × 10 ⁵ to
The synthetic resin material having a density of 3.3 × 10 ⁹ dyn / cm ² is preferably used as the base material auxiliary layer, and the layer thickness is preferably 5 to 80 μm. By laminating the base material auxiliary layer on the base material, a slivering resistance effect could be exhibited without increasing the total tape thickness.

[0035]

As described above, when the masking tape for coating of the present invention is used, when the masking tape is peeled off after completion of the coating, the parting step between the painted part and the unpainted part is reduced, and the parting line is obtained. When the masking tape is peeled off from the object to be coated in a state where the temperature of the coating film has been reduced, and after a while after the completion of painting, or in other low-temperature environments, the tape can be finished beautifully and beautifully. It is possible to easily peel off without breaking.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a preferred embodiment of a coating masking tape of the present invention according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Substrate auxiliary layer 3 ... Adhesive layer 4 ... Release agent layer 10 ... Masking tape

Continuation of the front page F term (reference) 4D073 AA01 BB03 DB03 DB08 DB14 DB15 DB28 DB32 4J004 AA04 AA05 AA10 AB01 CA03 CA04 CA05 CA06 CA07 CC03 CD01 DA03 DB03 EA01 FA04 FA10

Claims (4)

[Claims] 1. A coating masking tape comprising a base material and an adhesive layer, wherein the base material is made of a synthetic resin material, and on one or both sides of the base material, at least one layer of the same or the same as the base material A masking tape for coating, wherein base material auxiliary layers made of different synthetic resin materials are laminated. 2. The coating masking according to claim 1, wherein the elastic modulus of the synthetic resin material constituting the base material auxiliary layer is smaller than the elastic modulus of the base material at 0 to 40 ° C. tape. 3. The synthetic resin material constituting the base material auxiliary layer is, at 10 ° C., 1.0 × 10 ^{5 to} 1.0 × 10 ¹⁰
3. The coating masking tape according to claim 1, having an elastic modulus of dyn / cm < ² >. 4. A layer thickness of the base material auxiliary layer is 1 to 100 μm.
The masking tape for coating according to any one of claims 1 to 3, wherein