JPH02132173A - Water stopping tacky tape - Google Patents

Abstract

PURPOSE:To obtain the title tacky tape maintaining tack for a long period of time, having excellent water stopping properties, by setting a polymer substance layer having water swelling properties and tack at least on one side of flexible substrate layer having water resistance. CONSTITUTION:For example, a treated face of nonseparable type of substrate film such as polyethylene having one side subjected to release treatment is coated with a coating solution comprising a monomer of a polymer substance such as partially crosslinked polyvinylmethyl ether and irradiated with electron rays so that formation of polymer substance and integration of the polymer substance with the substrate are simultaneously carried out to give the aimed tacky tape. The tape is wound in such a way that the tacky face is brought into contact with one side subjected to release treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a water-stop adhesive tape, and more particularly to a water-stop adhesive tape that maintains adhesiveness for a long time and has excellent water-stop properties.

2. Description of the Related Art When connecting water distribution pipes, etc., adhesive tape is often wrapped around the connection part for the purpose of water stopping.

However, various types of troubles have occurred during such connections. That is, if the adhesive was not wrapped properly, water would leak out, and if the adhesive got wet, it would often become less sticky and peel off.

In order to avoid these problems, it has been considered to mix highly absorbent substances into the rubber sheet, but the response to swelling with water was slow and no effect was found on rapid water leakage.

PROBLEMS TO BE SOLVED BY THE INVENTION As mentioned above, it has been desired that water-stopping adhesive tapes used for connecting water distribution pipes, etc. be prevented from decreasing in adhesiveness and improved in water-stopping properties.

Means for Solving the Problems The present invention was made under such circumstances, and was completed as a result of focusing on the combination of a polymer substance having specific properties with a base material.

That is, the present invention provides a water-stopping adhesive tape characterized in that a polymer material layer having both water-swellability and adhesiveness is provided on at least one side of a flexible base layer having water resistance. It is. The present invention is characterized in that the adhesive used itself has water absorbing properties and swells immediately with water. This solves the problems mentioned in r.

The present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view schematically showing one specific example of the water-stop adhesive tape of the present invention. The second factor is a cross-sectional view schematically showing another specific example of the water-stop adhesive tape of the present invention. FIG. 3 is a sectional view schematically showing yet another specific example of the water-stopping adhesive tape of the present invention. In the drawings, A means a layer of a polymer material having both water-swellability and adhesiveness (hereinafter, such a polymer material is simply referred to as a polymer material), B means a flexible base layer, and C means a release paper layer. .

The waterproof adhesive tape of the present invention basically has a layered structure. That is, Figures 1 to 3 illustrate layered structures, and Figure 1 shows a two-layer structure consisting of one flexible base material layer (B) and one polymer material layer (A). , FIG. 2 shows a flexible base material layer (B) of 1 and 2 polymer material layers (B) provided on both sides thereof.
Figure 3 shows a three-layer structure consisting of A) and a flexible base material layer (
B) shows a three-layer structure consisting of one polymer material layer (A) and one release paper (C).

The polymeric substances to be used in these layered structures have both adhesiveness and water-swellability. In the past, the focus on adhesives in water-stop tapes was focused only on their tackiness, but
This time, the water-stopping effect has been improved by selectively using a polymeric material that also has water-swelling properties. That is, the gaps between the coils are tightly closed by swelling due to water.

Examples of polymeric substances having both adhesiveness and water-swellability include partially crosslinked polyvinyl methyl ether and partially crosslinked partially saponified polyvinyl acetate.

Alternatively, instead of a polymeric material that possesses both properties,
Compositions consisting of water-swellable superabsorbent polymeric materials and adhesives can also be used. Here, the adhesive may be a water-soluble substance such as gum arabic that becomes sticky when exposed to a small amount of moisture, or it may be a so-called sticky polymer substance such as acrylic or rubber. . In short, any material can be used as long as it is miscible with the highly water-absorbing substance and has tackiness as a mixture. Therefore, unless otherwise specified, the term "polymer material" in the present invention is intended to include such mixed compositions.

Examples of superabsorbent polymers to be used in the mixed composition include partially crosslinked acrylates, partially crosslinked copolymers of acrylates and polyvinyl alcohol, partially crosslinked polyethylene oxides and polyvinyl alcohol, etc. can be mentioned.

Next, the flexible base material used in the present invention may be any material that is generally used as a base material for adhesives, such as polyethylene, polypropylene, polyester, cellulose acetate, polyamide, polycarbonate, etc. Examples include so-called plastic sheets or films, paper made of natural fibers or synthetic fibers, fiber aggregate sheets such as woven fabrics, nonwoven fabrics, and the like.

As a method for manufacturing the LL water adhesive tape of the present invention from the above-described visible base material and a polymeric substance, for example, a heptanomer of a polymeric substance is applied to the non-release-treated side of a base film whose one side has been subjected to a release treatment. An example of this method is to apply a coating liquid consisting of the following and then irradiate it with an electron beam, thereby simultaneously producing the desired polymeric substance and integrating the polymeric substance into the base material. This is a specific manufacturing method shown in FIG. During manufacturing, the tape is wound up so that the adhesive surface is in contact with the release-treated surface.

As an alternative method, there is a method of manufacturing the water-stopping adhesive tape of the present invention by integrating a separately manufactured polymeric substance with a base material. For example, there is a method of kneading an adhesive and a highly absorbent substance, making it into a seal shape using an extruder, and laminating it on a base material at the same time, as shown in Figure 2. If objects to be adhered exist on both sides, a double-sided adhesive structure can be used. Furthermore, if the non-adhesive side of the base material has not been subjected to mold release treatment, the third
As shown in the figure, a structure in which a layer of release paper is provided can also be used. These can be produced in a single step or in a multistep process using conventional methods.

Thus, the water-stopping adhesive tape of the present invention obtained in the above-described manner can of course be applied to homes, factories, etc., but it can be particularly suitably used for welding plumbing pipes at construction sites and other special locations.

The present invention will be explained in more detail with reference to Examples below.

Example 1 A composition comprising the following components was applied to a thickness of 0.12 mm on the non-release treated surface of a 25 μm thick polyester release film (MR Release Film 25 μm, manufactured by Diafoil Co., Ltd.).

Ingredients Parts by weight Polyvinyl methyl ether 10050% aqueous solution (manufactured by BASF, Lutonal 1M40W) Polyethylene glycol 0.5 diacrylate (molecular weight 600) Immediately after application, use an area beam electron beam irradiation device manufactured by Nissin High Voltage Co., Ltd. In a nitrogen atmosphere, acceleration voltage was 200 KV, dose was 7 Mrad, and dose rate was 2 2 . 4
Electron beam irradiation was performed under the conditions of M rad/see, followed by heating and drying at 105° C. for 2 minutes, cooling, and winding to obtain a water-stop adhesive tape of the present invention.

In order to evaluate the performance of this adhesive tape, two pipes were fixed with their ends slightly separated, the ends were connected by wrapping adhesive tape, and water was flowed in this state for observation. It was confirmed that a small amount of water that leaked through the gaps between the layers was absorbed by the adhesive layer and swelled, and that this swelling served as a water stopper.

Example 2 The same composition as in Example 1 was applied to a partially fused nonwoven fabric with a basis weight of 40 g/m2 at a coating amount of 95 g/m'', and immediately using a scanning electron beam irradiation device manufactured by Nissin High Voltage Co., Ltd., Acceleration voltage 500KV, dose 5Mrad in nitrogen atmosphere
, dose rate 8. Electron beam irradiation was performed under the conditions of I Mrad/see, and the coated surface after irradiation was immediately bonded to one side of the film, which had been subjected to release treatment on both sides, and incubated at 105°C for 5 minutes.
It was dried for a minute, allowed to cool, and wound up to obtain a water-stop adhesive tape of the present invention.

This tape was tested in the same manner as in Example I.
It was confirmed that the tape had excellent water-stopping effects, just like the tape shown in the previous article.

Effects of the Invention The present invention provides a water-stopping adhesive tape that maintains adhesiveness for a long period of time, has excellent water-stopping properties, and can sufficiently cope with sudden water leakage.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a water-stopping adhesive tape of the present invention having a two-layer structure consisting of l flexible base material layer and l polymer material layer, and FIG. FIG. 3 is a cross-sectional view of a water-stopping adhesive tape of the present invention having a three-layer structure consisting of a material layer and two polymer material layers provided on both sides of the material layer, and FIG.
1 is a cross-sectional view of a water-stopping adhesive tape of the present invention having a three-layer structure consisting of a polymer material layer and a release paper layer. The symbols in the drawings have the following meanings. A; Polymer material layer B; Flexible base material layer C; Release paper layer Patent applicant Dynic Co., Ltd.

Claims (3)

[Claims] (1) A water-stopping pressure-sensitive adhesive tape, characterized in that a polymer material layer having both water-swellability and adhesiveness is provided on at least one side of a flexible base material layer having water resistance. (2) The water-stop adhesive tape according to claim (1), wherein the polymeric substance is a partially crosslinked polyvinyl methyl ether. (3) The water-stop adhesive tape according to claim (1), wherein the polymeric substance is a mixture of a superabsorbent polymer and a water-soluble adhesive substance.