JPH11166161A - Adhesive film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive film which, when a flat film on which a plurality of coated wires are mounted is heat-sealed, can arrange and hold the coated wires flatly without detriment to the necessary adhesiveness and flexibility. SOLUTION: An adhesive film is formed from a 60-400 μm thick flexible polyvinyl chloride resin film made from a mixture of 100 pts.wt. polyvinyl chloride resin and 25-65 pts.wt. (in terms of DOP) plasticizer and a 15-150 μm thick adhesive layer 2 comprising a hot melt adhesive and laid on either surface of the base material layer 1, and the adhesive film together with coated wires 3 is heat-sealed to arrange and hold the wires 3 flatly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive film obtained by applying a hot-melt type adhesive to a polyvinyl chloride resin film, and more particularly to a method in which a flat film on which a plurality of coated conductors are placed is heat-sealed. The present invention relates to an adhesive film for arranging and holding the covered conductors flat while having the required adhesive strength and flexibility.

[0002]

2. Description of the Related Art Conventionally, when binding a covered wire used for electric wiring of an automobile, an electric device or the like, an adhesive tape is wound around the covered wire by hand.

However, winding with an adhesive tape has the problem that the larger the number of covered conductors, the larger the diameter of the covered conductor bundle and the more difficult it is to wire to narrow locations.

[0004]

Here, in order to reduce the thickness of the bundle, as shown in FIG. 1, there is considered a means for reducing the thickness by sticking the covered conductor 3 on an adhesive film having a square of several centimeters. Can be

[0005] However, such means does not provide the coated conductor 3
The required high adhesive strength could not be obtained because the pressure-sensitive adhesive layer 2 holds only a part of the outer periphery of the substrate to be adhered.

[0006]

Means for Solving the Problems Accordingly, the present inventors have:
As a result of intensive studies to solve the above-mentioned problems, in an adhesive film having a film-shaped base layer and an adhesive layer on one side of the base layer, the base layer is made of polyvinyl chloride resin 10
A soft polyvinyl chloride resin film having a thickness of 60 to 400 μm is prepared by mixing 25 to 65 parts by weight (in terms of DOP) of a plasticizer with respect to 0 parts by weight.
By using a 0 μm hot-melt adhesive, it has been found that the coated conductors can be arranged and held flat while having the required adhesive strength and flexibility, and the above-mentioned problem has been solved.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The use of the above-mentioned polyvinyl chloride resin as a base material of the adhesive film according to the present invention is such that the base material layer itself fits the outer shape of the above-mentioned coated conductive wire when the adhesive layer is heat-sealed. This is to give them the flexibility to work.
If the thickness of the polyvinyl chloride resin is too small, the strength of the base material itself and the force for holding the adhesive are weakened and the adhesive strength is reduced, and if the thickness is too large, the adhesive film itself does not enter the gaps between the coated conductive wires. Therefore, preferably 6
0 to 400 μm, more preferably 150 to 250 μm
Is good.

The reason why the plasticizer is added to the polyvinyl chloride resin is to impart flexibility to the entire film. If the amount is too small, the effect of the plasticizer (softening) does not appear. If the amount is too large, the film becomes too soft at the beginning. Since the modulus is low, the compounding ratio is preferably 25 to 65 parts by weight, more preferably 40 to 55 parts by weight in terms of DOP. In addition, a stabilizer, a lubricant, a filler, a pigment and the like can be added to the polyvinyl chloride resin in addition to the plasticizer as long as the essence of the composition is maintained.

As the plasticizer, conventionally known plasticizers can be appropriately selected and employed, for example, DOP (di-2-ethylhexyl phthalate), DBP (dibutyl phthalate), DOA (di-2-ethylhexyl adipate),
DIDP (diisodecyl phthalate), epoxidized soybean oil, polyester plasticizer, trimellitate, and the like.

The reason why the adhesive layer is a hot-melt adhesive is that the adhesive strength can be exerted in a short time with a small amount of work (heating). For other adhesives, for example, a water-based adhesive requires a water supply step and a drying step for this water, and a solvent-based adhesive requires a step of volatilizing the solvent,
These are not worth adopting. Also, the thickness of the hot melt type adhesive is preferably 15 to 150 μm, more preferably 60 to 60 μm, because if it is too thin, the adhesive strength is weak, and if it is too thick, the unit price of the product becomes abnormally high.
１２０120 μm is preferred.

[0011] The hot melt type adhesive may be used in an amount of 80 to 120 to exhibit its adhesive force in a short time and comfortably.
C. Preferably, it has a melting point of.degree.
(Ethylene-vinyl acetate) type, polyester type, polyamide type, urethane type and the like. When the covering material of the covered conductor is soft polyvinyl chloride, EVA-based and urethane-based materials are preferable. When using the EVA system for a long time,
Since the EVA adhesive becomes too soft due to the transfer of the plasticizer, it is preferable to mix a polyamide resin. If the compounding ratio of this polyamide resin is too small, the effect is not exhibited, and if it is too large, the adhesive strength is reduced. Therefore, it is preferable to mix 3 to 20 parts by weight with respect to 100 parts by weight of the EVA resin.

In order to make the adhesive film according to the present invention flame-retardant, the oxygen index (JIS K 7201) of the soft polyvinyl chloride resin may be limited to 24-35. In adjusting the oxygen index, a flame retardant such as antimony trioxide may be added to a polyvinyl chloride resin as a base material. If the compounding ratio of the flame retardant is too small, the flame retarding effect is not exhibited, and if it is too large, the flame retarding effect reaches a plateau. Therefore, the mixing ratio is preferably 3 to 12 parts by weight with respect to 100 parts by weight of the polyvinyl chloride resin.

Although the term "adhesive film" is used in the present invention, it is needless to say that a tape-shaped or sheet-shaped film may be used as long as it has the above-mentioned thickness and other structures.

In the present invention, the film-like base material layer is formed by adding a plasticizer 25 to 100 parts by weight of the polyvinyl chloride resin.
Thickness 60-400 with 65 parts by weight (DOP conversion)
μm soft polyvinyl chloride resin film, and the adhesive layer is a hot melt type adhesive having a thickness of 15 to 150 μm,
Thus, the coated conductors can be arranged and held flat while having the adhesive strength and flexibility required as an adhesive film.

[0015]

EXAMPLES Comparative examples of an adhesive film according to an example of the present invention are shown in Tables 1 and 2 which disclose the materials and characteristic values thereof, and FIG. 1 and FIG. This will be described in detail with reference to FIG.

FIG. 1 is an explanatory view schematically showing a state in which a coated conductor is placed on an adhesive film of each embodiment and comparative example.
FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1 in each example. In the table, parts by weight of the plasticizer are DOP-converted values, and the unit N of the coated lead wire peeling force (the measuring method is described below) is It is Yuton, and the criteria of × for flexibility and cost will be described later.

[0017]

[Table 1]

[0018]

[Table 2]

The term "stripping force of the coated conductor" in the table refers to the peeling force when the heat-sealed coated conductor 3 is peeled off from the state of being placed on the adhesive film (see FIG. 1) in each of the examples and comparative examples. . A specific measuring method is to arrange 10 coated conductors made of a soft polyvinyl chloride resin having a diameter of 2.0 mm on the surface of the adhesive film coated with the adhesive, and to weigh 3 kg at 110 ° C. for 2 minutes using a heat sealer.
/ Cm ² under pressure and then allowed to stand at room temperature for 2 hours.
It was peeled off at a speed of minutes. As this value, 5.0 N or more is required, and 7.0 N or more is more preferable.

In the table, the flexibility was evaluated as ○ when the adhesive film itself was deformed according to the shape of the coated conductor after heat sealing, and as x when the adhesive film was not deformed. Further, the cost in the table is indicated by x when the cost is not satisfied as a product, and ○ when not.

Next, the adhesive film of the first embodiment will be described. Base film layer 1 of adhesive film in this embodiment
Is a plasticizer 5 per 100 parts by weight of polyvinyl chloride resin.
0 parts by weight (in terms of DOP) were blended and formed to a thickness of 150 μm. The adhesive layer 2 is formed by applying an EVA hot-melt adhesive of 80 μm in which 10 parts by weight of a polyamide resin is blended with 100 parts by weight of an ethylene vinyl acetate resin to the base layer 1 by extrusion lamination. Unless otherwise described, other examples and comparative examples described below are manufactured by the same manufacturing method as this example and have the same configuration.

The third method in which the mixing ratio of the plasticizer in the base material layer is changed
Comparing the comparative example, the first, fourth and fifth examples, and the fourth comparative example (plasticizer compounding ratio 20, 35, 50, 60 and 70), if the amount of the plasticizer is too small, it is too hard. It was easy to be peeled off, and even if it was too much, it was too soft and easily peeled off.

The first comparative example, the first embodiment, and the second comparative example (thicknesses 50, 150 and 50) in which the thickness of the base material layer was changed.
Compared with 0), when the thickness is thin, the coated conductive wire peeling force is poor, and when the thickness is thick, there is a problem in terms of flexibility and cost.

A comparison of the first embodiment, the sixth embodiment, the seventh and the eighth comparative example, in which the material of the hot melt type adhesive was measured, shows that EVA (ethylene-vinyl acetate) resin, urethane-based adhesive However, the polyester resin and the polyamide resin have problems in terms of the peeling force of the coated conductor and the cost.

The fifth comparative example, the second, the first and the third examples, and the sixth example, which were measured by changing the thickness of the hot melt type adhesive.
Comparing the comparative examples, it can be seen that the peeling force of the coated conductor changes according to the thickness. If it is too thin, there is a problem in the peeling force of the coated wire, and if it is too thick, there is a problem in cost.

Next, the case where the compounding ratio of the flame retardant is changed will be described. The oxygen index (JIS K7) of the base material layer when the flame retardant was not blended in the blending of the first embodiment.
201) was 23, 28 when 6 parts by weight of the flame retardant was added, and 30 when 20 parts by weight of the flame retardant was added. As a result, an adhesive film having a high flame retardant effect could be obtained.

[0027]

According to the present invention, there is provided an adhesive film having a film-like substrate layer and an adhesive layer on one surface of the substrate layer.
The base material layer is a soft polyvinyl chloride resin film having a thickness of 60 to 400 μm in which 25 to 65 parts by weight (in terms of DOP) of a plasticizer is blended with respect to 100 parts by weight of the polyvinyl chloride resin. A hot-melt adhesive having a thickness of 15 to 150 μm can be used to arrange and hold the coated conductors flat while having the required adhesive strength and flexibility.

In another invention, since the soft polyvinyl chloride resin has an oxygen index of 24 to 35, an adhesive film having a high flame retardant effect can be obtained.

In another invention, 3-20 parts by weight of a polyamide resin is mixed with 100 parts by weight of an ethylene vinyl acetate resin, and the melting point of the entire adhesive is 80-120 ° C. Thereby, it is possible to obtain an adhesive film having a long-term stable adhesive force.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing a state in which a coated conductive wire is placed on an adhesive film (or an adhesive film) of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base material layer 2 Adhesive layer 3 Coated wire

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kishio Niwayama 2-13-1, Dai, Kamakura-shi, Kanagawa Prefecture Inside Toyo Kagaku Co., Ltd. (72) Inventor Akira Goto 2-13-1, Dai, Kamakura-shi, Kanagawa Toyo Within Chemical Co., Ltd. (72) Inventor Tadashi Ogushi, 2-13-1, Dai, Kamakura-shi, Kanagawa Prefecture, Toyo Chemical Co., Ltd.

Claims (3)

[Claims] 1. An adhesive film having a film-shaped base layer (1) and an adhesive layer (2) on one surface of the base layer (1), wherein the base layer (1) is made of polyvinyl chloride. Resin 100
25 to 65 parts by weight of plasticizer based on parts by weight (DOP equivalent)
Is a soft polyvinyl chloride resin film having a thickness of 60 to 400 μm, wherein the adhesive layer (2) has a thickness of 15 to
An adhesive film comprising a hot-melt adhesive of 150 μm. 2. The adhesive film according to claim 1, wherein said flexible polyvinyl chloride resin has an oxygen index of 24 to 35. 3. The hot-melt adhesive comprises 3 to 20 parts by weight of a polyamide resin with respect to 100 parts by weight of an ethylene vinyl acetate resin.
3. The method according to claim 1, wherein the temperature is 120.degree.
The adhesive film as described.