JP2002294187A - Pressure-sensitive adhesive sheet for tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent peeling, e.g. during tire transport. SOLUTION: The pressure-sensitive adhesive sheet for a tire is prepared by forming an anchor coat 3, a vinylidene chloride-vinyl chloride copolymer layer 4, and a pressure-sensitive adhesive layer 5 in this order on one side of a substrate sheet 2 mainly comprising polypropylene and containing a white pigment. The tackiness of the pressure-sensitive adhesive sheet to a polyethylene plate according to JIS Z 0237 is 1,000-2,700 g/25 mm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive adhesive sheet for a tire used for a display label of a rubber tire such as an automobile tire.

[0002]

2. Description of the Related Art Conventionally, pressure-sensitive adhesive sheets have a pressure-sensitive adhesive layer on at least one of the front and back surfaces, and are widely used for various label applications and seal products. One of such pressure-sensitive adhesive sheets is a pressure-sensitive adhesive sheet for tires. On the pressure-sensitive adhesive sheet for tires, information such as a tire name, a manufacturer name, and a price is printed on one surface, and a pressure-sensitive adhesive layer is provided on the other surface, and the pressure-sensitive adhesive layer is attached to the tire via the pressure-sensitive adhesive layer. Is used for quality control or for a purchaser to know tire characteristics and the like.

In general, the pressure-sensitive adhesive sheet for tires is often attached to a tread surface having a curved surface and an uneven tread pattern formed for the purpose of enhancing drainage or preventing slippage. It is required to have a certain degree of flexibility along the tread surface and adhesiveness that does not peel off even when attached to the rough tread surface. Moreover, on the other hand, if the adhesive strength is excessively high or the affinity between the adhesive layer and the rubber is high, the adhesive remains on the tread surface after peeling, and garbage and the like adhere to the tread surface, and the appearance deteriorates. When using the adhesive, the adhesive sheet must be peeled off so that no adhesive remains on the tread surface.

Conventionally, in a pressure-sensitive adhesive sheet for a tire, a black pigment, an amine-based antioxidant, an aromatic-based content, and the like contained in a rubber tire are leached into a support sheet via an adhesive surface.
In order to prevent the support sheet from being blackened in a short period of time due to so-called bleeding, a PET-based support sheet having relatively high stability to a solvent and having a certain degree of flexibility has been generally used.

[0005]

SUMMARY OF THE INVENTION However, PET
Is relatively hard, and therefore, a conventional pressure-sensitive adhesive sheet for a tire mainly comprising the same often lacks flexibility and is often unintentionally peeled off from the tire during storage or transportation. In addition, when affixed to a tire for a long period of 6 months or more, the tire sometimes became black due to bleeding.

[0006] In order to improve the releasability, it is conceivable to reduce the thickness of the support sheet to make it flexible, or to increase the thickness of the adhesive layer to increase the adhesiveness. However, when the thickness of the support sheet is excessively reduced, the concealing property and the bleeding resistance deteriorate. The concealing property is improved by the aluminum vapor deposition treatment, but the bleeding resistance is not improved. In addition, the aluminum deposition process is not preferable because it is a very expensive process and increases the cost. When the thickness of the pressure-sensitive adhesive layer is increased as in the latter case, the pressure-sensitive adhesive tends to protrude during recording of printing or the like, and adhesive residue is liable to occur, which is not preferable.

[0007] Therefore, a main object of the present invention is to provide a flexible and suitably affixable to a tread surface of a tire to prevent unintended peeling, and to be easily peeled at the time of use so that there is no adhesive residue. An object of the present invention is to provide an inexpensive pressure-sensitive adhesive sheet for a tire, which does not cause blackening of a support sheet due to bleeding even when attached to a tire.

[0008]

According to a first aspect of the present invention, there is provided a support sheet mainly made of polypropylene, comprising an adhesive layer made of an anchor coating agent, a vinylidene chloride vinyl chloride film and a vinyl chloride layer. A pressure-sensitive adhesive sheet for a tire, wherein a polymer layer and a pressure-sensitive adhesive layer are provided in this order.

By using a support sheet mainly composed of polypropylene, it becomes supple and can be suitably attached to a tread surface of a tire, and unintended peeling is prevented. Further, since the vinylidene chloride vinyl chloride copolymer layer for protecting the support sheet from the tire-containing substance is provided, bleeding does not occur.

In addition, since the vinylidene chloride vinyl chloride copolymer layer can be easily formed by coating with a conventionally known coating machine, it can be manufactured at low cost.

The pressure-sensitive adhesive sheet for a tire is JIS Z
Adhesion to polyethylene plate according to 0237 is 1
It is preferably from 000 to 2700 g / 25 mm.

When the adhesive strength is within such a range, the adhesive can be peeled very easily during use, and the adhesive does not remain on the tire tread surface after peeling. Here, JIS Z
The adhesive strength to a polyethylene plate according to 0237 is
It is the adhesive force measured by changing the test plate in JIS Z 0237 from a stainless plate to a polyethylene plate. In addition, what wash | cleans polyethylene is not used for washing | cleaning of a test plate.

On the other hand, the pressure-sensitive adhesive sheet for a tire is provided with an ink-receiving layer such as an easy-adhesion coat on the exposed surface of the support sheet, or the exposed surface of the support sheet is subjected to corona discharge treatment to improve printability. In addition, recording performance can be improved.

On the other hand, it is preferable to use the support sheet containing a white pigment for the pressure-sensitive adhesive sheet for a tire. When a white pigment is contained in the support sheet, the whiteness is increased and the recorded information can be printed clearly, and the appearance is improved and the sense of quality is increased.

[0015]

Embodiments of the present invention will be described in detail below. FIG. 1 shows a sectional view of the pressure-sensitive adhesive sheet for a tire of the present invention.

The pressure-sensitive adhesive sheet S for a tire according to the present invention comprises, on one surface of a support sheet 1 mainly composed of polypropylene, an adhesive layer composed of an anchor coating agent 2, a vinylidene chloride-vinyl chloride copolymer layer 3, and a pressure-sensitive adhesive. The pressure-sensitive adhesive sheet for a tire, wherein the layers 4 are provided in this order. In the illustrated example, an ink receiving layer 5 is provided on the opposite surface of the support sheet by an easy-adhesion coat.

The vinylidene chloride-vinyl chloride copolymer is generally applied as a moisture-absorbing agent to release paper or the like. The present inventors have paid attention to this vinylidene chloride-vinyl chloride copolymer. As a result of repeated studies, they have found that they have almost the same bleeding prevention ability as the aluminum vapor deposition layer. The present invention is based on this finding. Further, in the present invention, a support sheet mainly composed of polypropylene is used in order to impart flexibility to the support sheet. Although there is generally difficulty in adhesion between a support sheet mainly composed of polypropylene and a vinylidene chloride-vinyl chloride copolymer, in the present invention, by providing an anchor coat layer, such adhesion is improved. I have.
In the present invention, the anchor coat layer refers to a portion existing between the support sheet and the vinylidene chloride-vinyl chloride copolymer and adhering both layers by an anchoring effect, and is not necessarily a uniform layer.

The thickness of the support sheet is from 40 to
It is preferably 90 μm. When it is less than 40 μm,
The concealment property deteriorates. If it exceeds 90 μm, it will lack flexibility, and it will be difficult to adhere along a curved surface, and unintended peeling will easily occur.

Light calcium carbonate, heavy calcium carbonate, kaolin, clay, talc,
Calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic silica, aluminum hydroxide, alumina, lithopone, zeolite, magnesium carbonate, water It preferably contains a known white pigment such as magnesium oxide.

In the base material of the present invention, other additives such as a pigment dispersant, a thickener, a flow improver, an antifoaming agent, a foam inhibitor, a release agent, a foaming agent, a penetrant, A coloring dye, a coloring pigment, a fluorescent whitening agent, an ultraviolet absorber, an antioxidant, a preservative, an antibacterial agent and the like may be blended.

On the other hand, the viscosity of the anchor coat layer is adjusted by dissolving an anchor coat agent in a conventionally known organic solvent or the like, and a conventional bar coater, blade coater, die coater, roll coater, gravure coater, air knife coater or the like is used. It can be provided by coating the support sheet with a known coating machine. At this time, the thickness of the dried anchor coat layer is 1 to 10 μm
So that

As the anchor coating agent, a conventionally known anchor coating agent can be used without any problem.
Specific examples include Takelac A-310 (manufactured by Takeda Pharmaceutical Company) and Takenate A-3 (manufactured by Takeda Pharmaceutical Company). The anchor coating agent may be used singly or as a mixture of two or more if possible.

On the other hand, the vinylidene chloride vinyl chloride copolymer layer is formed on the anchor coat layer using a conventionally known coating machine such as a comma coater, a bar coater, a blade coater, a die coater, a roll coater, a gravure coater or an air knife coater. Can be provided by coating on a support sheet provided with. At this time, the coating amount of the vinylidene chloride vinyl chloride copolymer is desirably 3 to 15 g / m ² . When it is less than 3 g / m ² , the effect of preventing bleeding of the tire-containing substance is not easily obtained,
On the other hand, if it exceeds 15 g / m ² , coating unevenness is likely to occur, and the pressure-sensitive adhesive sheet as a whole becomes too thick, which is not preferable.

On the other hand, the pressure-sensitive adhesive layer may be formed by coating a conventionally known pressure-sensitive adhesive such as a natural rubber, acrylic, urethane, silicon or the like with a comma coater, bar coater, blade coater, die coater, roll coater, gravure coater, or the like. It can be provided by coating the vinylidene chloride vinyl chloride copolymer layer using a conventionally known coating machine such as an air knife coater. Specific examples of the pressure-sensitive adhesive include, for example, natural rubber, natural rubber latex in which natural rubber is sulfur-free vulcanized and mixed with methyl methacrylate, or natural rubber obtained by graft-polymerizing methyl methacrylate on natural rubber. Rubber latex, acrylic modified rubber latex, adhesives such as a mixture of rubber latex and protective colloidal acrylic copolymer emulsion as a base material, natural resin such as rosin, polyterpene resin,
Examples thereof include those containing a tackifier such as an aliphatic hydrocarbon resin, a cyclopentadiene resin, an aromatic resin, or a phenol resin.

The coating amount of the pressure-sensitive adhesive is 20 to 50 g / m
^It is preferred to be in the range of ² . If it is less than 20 g / m ² , the tackiness is insufficient, and if it is more than 50 g / m ² , uneven coating or protrusion from the support sheet tends to occur. In addition, an accident of adhesive residue remaining on the tire surface is likely to occur.

On the other hand, the pressure-sensitive adhesive sheet for a tire of the present invention
It is desirable that the adhesive force to a polyethylene plate according to ISZ0237 be 1000 to 2700 g / 25 mm. The adhesive strength can be adjusted by the amount of the adhesive applied and the content of various tackifiers. 1000
When it is less than g / 25 mm, the adhesiveness to the tire surface is inferior, and peeling is likely to occur at the time of transporting the tire or during display. 2700
If it exceeds g / 25 mm, the pressure-sensitive adhesive may remain on the tire surface during peeling.

On the other hand, the pressure-sensitive adhesive surface of the tire pressure-sensitive adhesive sheet is desirably protected with a release sheet before use, ie, before the tire is attached, from the viewpoint of operability during handling and recording. As the release sheet, a conventionally known release sheet for an adhesive sheet such as glassine paper, clay coated paper, kraft paper, or laminated paper can be used without any problem.

If the pressure-sensitive adhesive layer is protected by a release sheet, the pressure-sensitive adhesive is applied to the release sheet, and the pressure-sensitive adhesive layer and the vinylidene chloride-vinyl chloride copolymer layer are adhered to the pressure-sensitive adhesive layer of the present invention. Sheets can also be manufactured.

On the other hand, on the opposite surface of the support sheet of the present invention, that is, the surface on which the vinylidene chloride vinyl chloride copolymer layer is not provided, it is desirable to form an ink receiving layer by an easy adhesion coat or the like. The opposite surface may be subjected to corona discharge treatment. Various information is recorded on the surface of the pressure-sensitive adhesive sheet for tires that is opposite to the surface of the pressure-sensitive adhesive layer. I do.

Specifically, the ink receiving layer is formed by coating a coating agent containing an ink fixing agent or the like with a known coating agent such as a comma coater, a bar coater, a blade coater, a die coater, a roll coater, a gravure coater, or an air knife coater. The support sheet can be provided by coating using a machine. The characteristics of the ink receiving layer can be appropriately selected in consideration of various printing methods of recording information.
For example, if recording information is to be recorded by an inkjet recording method, an inkjet printing method is performed by applying a coating agent containing a binder, a white pigment such as calcium carbonate or kaolin, an ink fixing agent such as a cationic surfactant, and the like. An ink receiving layer suitable for a recording method is formed.

In the present invention, the application of the tire to be stuck is not limited. Suitable for automobiles, aircrafts, bicycle tires, trolleys, and various other tires.
The effects of the present invention are achieved. In addition, the present invention can be suitably affixed to various rubber products having the same characteristics as tires in addition to tires, and has the same effects as the effects of the present invention.

<Experimental Examples> Examples of the present invention and comparative examples are shown below.

[Example 1] An anchor coating agent (Takelac A-310 and Takenate A-3) was coated on a support sheet mainly composed of polypropylene (PP) having a thickness of 60 µm.
Both are manufactured by Takeda Pharmaceutical Co., Ltd.) and solvent (ethyl acetate)
And a mass ratio of 10: 1: 42.4 (Takerac A31
0: Takenate A-3: ethyl acetate) was applied by a comma coater to provide an anchor coat layer 5 g / m ² on the support sheet. Then
On the anchor coat layer, vinylidene chloride vinyl chloride copolymer (Saran latex: manufactured by Asahi Kasei Corporation)
Coating was performed with a comma coater to provide a vinylidene chloride vinyl chloride copolymer layer 9 g / m ² . Thereafter, an acrylic pressure-sensitive adhesive was applied on the vinylidene chloride vinyl chloride copolymer layer with a comma coater to provide a pressure-sensitive adhesive layer of 40 g / m ² , and a pressure-sensitive adhesive sheet for tires as Example 1 was obtained. Was.

Example 2 An anchor coat agent (Takelac A-310 and Takenate A-3) was applied to a support sheet mainly composed of polypropylene (PP) having a thickness of 40 μm.
Both are manufactured by Takeda Pharmaceutical Co., Ltd.) and solvent (ethyl acetate)
And a mass ratio of 10: 1: 42.4 (Takerac A31
0: Takenate A-3: ethyl acetate) was applied using a comma coater to provide an anchor coat layer 1 g / m ² on the support sheet. Then
On the anchor coat layer, vinylidene chloride vinyl chloride copolymer (Saran latex: manufactured by Asahi Kasei Corporation)
Coating was performed with a comma coater to provide a vinylidene chloride vinyl chloride copolymer layer of 3 g / m ² . Thereafter, an acrylic pressure-sensitive adhesive was applied on the vinylidene chloride-vinyl chloride copolymer layer with a comma coater to provide a pressure-sensitive adhesive layer of 20 g / m ² , thereby obtaining a pressure-sensitive adhesive sheet for tire according to Example 2. Was.

Example 3 An anchor coating agent (Takelac A-310 and Takenate A-3) was applied to a support sheet mainly composed of polypropylene (PP) having a thickness of 90 μm.
Both are manufactured by Takeda Pharmaceutical Co., Ltd.) and solvent (ethyl acetate)
And a mass ratio of 10: 1: 42.4 (Takerac A31
0: Takenate A-3: ethyl acetate) was applied using a comma coater to provide an anchor coat layer of 10 g / m ² on the support sheet. Next, a vinylidene chloride vinyl chloride copolymer (Saran latex: manufactured by Asahi Kasei Corporation) is formed on the anchor coat layer.
Was applied with a comma coater to provide a vinylidene chloride vinyl chloride copolymer layer of 15 g / m ² . Thereafter, an acrylic pressure-sensitive adhesive was applied on the vinylidene chloride vinyl chloride copolymer layer with a comma coater,
A pressure-sensitive adhesive sheet for tires as Example 3 was obtained by providing a pressure-sensitive adhesive layer of 40 g / m ² .

Example 4 An anchor coating agent (Takelac A-310 and Takenate A-3) was coated on a support sheet mainly composed of polypropylene (PP) having a thickness of 40 μm.
Both are manufactured by Takeda Pharmaceutical Co., Ltd.) and solvent (ethyl acetate)
And a mass ratio of 10: 1: 42.4 (Takerac A31
0: Takenate A-3: a mixture of ethyl acetate), was coated by a comma coater, an anchor coat layer 10 g / m ² provided on the support sheet. Next, a vinylidene chloride vinyl chloride copolymer (Saran latex: manufactured by Asahi Kasei Corporation) is formed on the anchor coat layer.
Was applied with a comma coater to provide a vinylidene chloride vinyl chloride copolymer layer of 15 g / m ² . Thereafter, an acrylic pressure-sensitive adhesive was applied on the vinylidene chloride vinyl chloride copolymer layer with a comma coater,
A pressure-sensitive adhesive sheet for tires, which was provided with a pressure-sensitive adhesive layer of 50 g / m ^{2 and} was Example 4, was obtained.

Comparative Example 1 A support sheet mainly composed of polypropylene (PP) having a thickness of 75 μm was coated with vinylidene chloride vinyl chloride copolymer (Saran latex: manufactured by Asahi Kasei Corporation) using a comma coater. And a vinylidene chloride vinyl chloride copolymer layer of 9 g / m ² . Thereafter, an acrylic pressure-sensitive adhesive was applied on the vinylidene chloride vinyl chloride copolymer layer with a comma coater to provide a pressure-sensitive adhesive layer of 40 g / m ² , and a pressure-sensitive adhesive sheet for tires as Comparative Example 1 was obtained. Was.

Comparative Example 2 A support sheet mainly composed of polypropylene (PP) having a thickness of 60 μm was subjected to an aluminum vapor deposition treatment to provide a 12 μm aluminum vapor-deposited layer. Next, an acrylic pressure-sensitive adhesive was applied on the aluminum vapor-deposited layer with a comma coater to provide a pressure-sensitive adhesive layer of 40 g / m ² .
A pressure-sensitive adhesive sheet for tires as Comparative Example 2 was obtained.

Comparative Example 3 An anchor coating agent (Takelac A-310 and Takenate A-3: both manufactured by Takeda Pharmaceutical Co., Ltd.) and a solvent (ethyl acetate) were applied to a 60 μm-thick PET-based support sheet. And the mass ratio 1
0: 1: 42.4 (Takelac A310: Takenate A
-3: ethyl acetate) was applied by a comma coater to provide an anchor coat layer 5 g / m ² on the support sheet. Next, a vinylidene chloride vinyl chloride copolymer (Saran Latex: manufactured by Asahi Kasei Corporation) was applied on the anchor coat layer by a comma coater, and a vinylidene chloride vinyl chloride copolymer layer 9 was formed.
g / m ² . Thereafter, an acrylic pressure-sensitive adhesive was applied on the vinylidene chloride vinyl chloride copolymer layer with a comma coater to provide a pressure-sensitive adhesive layer of 40 g / m ² , and a pressure-sensitive adhesive sheet for tires as Comparative Example 3 was obtained. Was.

COMPARATIVE EXAMPLE 4 A 12 μm-thick aluminum-evaporated layer was provided on a 12 μm-thick support sheet mainly composed of PET by subjecting it to aluminum evaporation. Next, an acrylic pressure-sensitive adhesive was applied on the aluminum-deposited layer with a comma coater to provide a pressure-sensitive adhesive layer of 40 g / m ^2.
Was obtained.

Comparative Example 5 An acrylic pressure-sensitive adhesive was applied to a 30 μm-thick PET-based support sheet with a comma coater to provide a pressure-sensitive adhesive layer of 60 g / m ^2. A pressure-sensitive adhesive sheet for a tire was obtained.

Table 1 shows the results of various evaluations of Examples and Comparative Examples.

[0043]

[Table 1]

<Evaluation method> The evaluation methods described in the table are as follows. The adhesive strength in the table is based on JIS
It is a value measured according to Z0237.

[Curve Surface Followability] A test piece cut into a size of 100 mm × 100 mm was cut from each of the examples and comparative examples, and the test piece was stuck to a tire for 6 months at a temperature of 23 ° C. and a humidity of 50%.
After being left in the environment, the peeling state of the pressure-sensitive adhesive sheet for tires was visually judged. If no peeling occurred,
Those having peeled were evaluated as x.

[Hiding Property] A test piece cut into a size of 100 mm × 100 mm was cut from each of the examples and comparative examples, and was attached to a tire, and the black transmittance of the tire was visually determined. When the black color of the tire was not seen through, it was evaluated as ○, and when it was seen through, it was evaluated as ×.

[Glue residue] A test piece cut into a size of 100 mm x 100 mm was cut from each of the examples and comparative examples, attached to a tire, and left for 2 months in an environment at a temperature of 23 ° C and a humidity of 50%. The state of adhesion of the pressure-sensitive adhesive to the tire when peeled off manually was determined visually. A tire to which no adhesive was attached was evaluated as タ イ ヤ, and an adhesive was evaluated as ×.

[Exfoliation] A test piece cut into a size of 100 mm × 100 mm was cut from each of the examples and comparative examples, attached to a tire, left for 6 months in an environment of a temperature of 23 ° C. and a humidity of 50%, and then manually worked. Judging from the difficulty situation at the time of peeling. Those that could be easily removed were evaluated as ○, and those that were not easily removed were evaluated as x.

[Bleeding] A test piece cut into a size of 100 mm × 100 mm was cut from each of the examples and comparative examples, and attached to a tire.
After leaving in a 0% environment, blackening due to bleeding of the tire pigment on the surface of the pressure-sensitive adhesive sheet for tires was visually judged. Those that were not blackened were evaluated as ○, and those that were blackened were evaluated as x.

[Cost merit] The production cost was compared based on the aluminum deposition layer. A sample whose production cost was lower than that of the aluminum vapor deposition process was evaluated as ○, and a sample whose production cost was equal to or higher than the aluminum vapor deposition process was evaluated as ×.

As can be seen from the table, the results of the embodiment of the present invention are evaluated as ○ in any of the evaluations, while those of the comparative example are evaluated as x. In summary, the embodiment of the present invention has an effect superior to that of the comparative example.

[0052]

As described above in detail, according to the present invention, it can be suitably attached to a tread surface of a tire and the like, and can be easily peeled off at the time of use. An adhesive sheet for a tire is provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a pressure-sensitive adhesive sheet for a tire according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Support sheet, 2 ... Anchor coat layer, 3 ... Vinylidene chloride vinyl chloride copolymer layer, 4 ... Adhesive layer, 5 ... Ink receiving layer, S ... Adhesive sheet for tires,

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J004 AA07 AB01 CA04 CB03 CC02 CE01 EA06 FA01

Claims (3)

[Claims] 1. An adhesive for tires, wherein an anchor coat layer, a vinylidene chloride vinyl chloride copolymer layer and an adhesive layer are provided in this order on one surface of a support sheet mainly composed of polypropylene. Sheet. 2. The pressure-sensitive adhesive sheet for a tire according to JIS Z
Adhesion to polyethylene plate according to 0237 is 1
The pressure-sensitive adhesive sheet for a tire according to claim 1, wherein the weight is 2,000 to 2700 g / 25 mm. 3. The pressure-sensitive adhesive sheet for a tire according to claim 1, wherein the support sheet contains a white pigment.