JP3111439B2 - Adhesive fixing members for molded products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molded article bonding / fixing member capable of stably adhering and fixing a molded article such as a resin molded article or a metal molded article to an adherend for a long period of time.

[0002]

2. Description of the Related Art There is a method in which a resin molded product such as an emblem or a protect molding is forcibly followed and adhered and fixed to a cubic curved surface of an automobile body or a single vehicle using an adhesive fixing member having a foam as a core. Generally known. However, when these molded products are fixed to a complicated cubic curved surface, they are peeled off for a long time due to the resilience of the molded products and the elasticity of the foam. In addition, dust and the like may enter and degrade the pressure-sensitive adhesive layer of the adhesive fixing member, and eventually, the molded product may fall off. In order to solve such a problem, Japanese Patent Application Laid-Open No.
In the publication, a 25% compression hardness having an apparent density of 0.05 to 0.8 g / cm ² is 0.5 to 1.7 kgf / c.
It proposes that used in the central core of the polyolefin foam of m ^2. However, the three-dimensional body, the complexity of the molded article, and the reduction in the size of the molded article have reduced the bonding area of the resin molded article. Furthermore, in the poly olefin foam in JP-A-57-10671, because that increases the flexibility of the foam for the purpose of lowering the 25% compressive hardness, tensile foam TsuyoShin As a result,
When an operator attaches an adhesive fixing member to a molded product, the member is stretched and the attaching workability is reduced, and there is also a drawback that the original performance is hardly exhibited.

[0003]

DISCLOSURE OF THE INVENTION The present inventors have conducted research on a molded product adhesive fixing member which can firmly adhere and fix a molded product to an adherend and has a sufficient tensile strength and elongation. As a result, they have found that the above object can be achieved by changing the closed cells in the core from a true sphere to an elliptical cross section, and have reached the present invention.

[0004]

According to the present invention, there is provided a member for fixing and fixing a molded article having a foam as a core and a pressure-sensitive adhesive layer formed on both surfaces thereof, wherein the major axis is the core. Characterized in that closed cells having an elliptical cross section extending in parallel with the length direction of the molded article are provided.

[0005] The molded article in the present invention is an object to be adhered to an adherend, and there is no particular limitation on the material and the shape. Examples thereof include resin products such as an automobile side protect mall and an emblem. Examples of the adherend include, but are not limited to, a resin substrate, a painted bumper, and a painted surface of an automobile.

[0006] The foamed structure of the core used in the present invention has an average length of 1 in the major axis direction elongated in the length direction of the core.
0 μm to 200 μm, average length in the minor axis direction is 8.3
It is a closed-cell structure having an elliptical cross section having a size of from 16 μm to 166.7 μm, and the ratio of the average length of the major axis to the average length of the minor axis (major axis length / minor axis length) is 1.2 or more. Is preferred. When the ratio is less than 1.2, flexibility in the thickness direction cannot be obtained, shape followability with respect to irregularities on the surface of a molded product, an adherend, or the like is reduced, and the bonding area and strength are reduced. Further, the expansion ratio of the foam used in the present invention is preferably from 5 to 15 times, and more preferably from 8 to 13 times. If it is less than 5 times, sufficient flexibility cannot be obtained, and if it exceeds 15 times, both the foam tensile strength and the interlaminar strength decrease, resulting in a decrease in the workability of application and interlaminar fracture after adhesion and fixing. Further, the foam structure may be mixed with the spherical closed cells and open cells.

The foam used in the present invention has a thickness of 0.1
To 1.5 mm, preferably 0.2 mm to 1.0 m
m, the tensile strength is 1 to 100 kgf / cm ² , preferably 10 to 50 kgf / cm ² , and the elongation at break is 100% or more, preferably 200% or more. Foam used in the present invention, cold resistance required for the molded product adhesive fixing member,
It is desirable that the material has properties such as heat resistance, water resistance, oil resistance, chemical resistance, weather resistance, vibration resistance, and shock resistance. As the foam having such characteristics, specifically, a polyolefin-based foam sheet made of polyethylene, polypropylene, an ethylene-propylene copolymer, an ethylene-vinyl acetate copolymer, and the like, an acrylic rubber and other elastomers And the like.

[0008] Such a foam is obtained, for example, by subjecting polyethylene containing a chemical foaming agent to irradiation with an electron beam to continuously heat a crosslinked sheet to form a highly foamed sheet, and then slicing the foamed sheet in the thickness direction. Is stretched in the length direction with a hot roll and skinned. Commercially available products include Toray Pef 10010-NM0 manufactured by Toray Industries, Inc.
0 (foaming ratio: 10 times, thickness: 1.0 mm), Torrefef 1
0008-NM00 (expansion ratio 10 times, thickness 0.8m
m), Torrefef 07008-NM00 (expansion ratio 7)
Times, thickness 0.8 mm) and the like, but is not limited thereto.

The pressure-sensitive adhesive used in the present invention includes:
Although not particularly limited, in terms of weather resistance and the like,
It is desirable to use a (meth) acrylic polymer.
The thickness of the pressure-sensitive adhesive layer is generally from 5 to 500 μm, preferably from 10 to 300 μm. When the pressure-sensitive adhesive layer is applied to a thickness of 200 μm or more, it is desirable to use an ultraviolet-curable pressure-sensitive adhesive from the viewpoint of coating workability.

[0010] The member for bonding and fixing a molded product according to the present invention comprises:
Before affixing to a molded product or an adherend, a separator is provided on at least one surface of the member, and the member is in a tape shape or a sheet shape. Examples of the separator include paper, a plastic film, and the like, on at least one surface of which the release treatment is performed. However, when the separator has a low energy surface, the separator may not be subjected to the release treatment.

[0011]

The molded article bonding and fixing member according to the present invention is characterized in that the core is provided with closed cells having a long axis extending parallel to the length direction of the core and having an elliptical cross section. Demonstrates good shape-following properties on irregularities on the surface of molded products and adherends without lowering the workability of attaching or lowering the tensile strength of the members. Since the flexibility in the thickness direction absorbs the stress, a good adhesion state can be maintained for a long time.

[0012]

EXAMPLES Examples are shown below, but the molded article adhesive fixing member of the present invention is not limited to these examples.

Example 1 A low-density polyethylene foam sheet ( Toray Pef 070 manufactured by Toray Industries, Inc.) having a thickness of 0.8 mm, an expansion ratio of 7 times, and a foam cell having an average long axis distance of 35 μm and an average short axis distance of 10 μm.
08-NM00) is subjected to corona discharge treatment, and an acrylic pressure-sensitive adhesive layer (80 μm) composed of a polymer containing alkyl acrylate as a main component and a cross-linking agent is provided on both surfaces thereof. A member for bonding and fixing the object was obtained.

Example 2 A low-density polyethylene foam sheet ( Toray Pef 10 manufactured by Toray Industries , Ltd.) having a thickness of 0.8 mm, an expansion ratio of 10 times, an average long axis distance of foam cells of 35 μm and an average short axis distance of 10 μm.
008-NM00) was obtained in the same manner as in Example 1 except that the both surfaces of which were subjected to corona discharge treatment were used.

Example 3 A low-density polyethylene foam sheet having a thickness of 0.4 mm, an expansion ratio of 10 times, an average long axis distance of foam cells of 35 μm, and an average short axis distance of 10 μm (Traype 10 made by Toray Industries, Inc.)
004-NM00) was obtained in the same manner as in Example 1, except that the both surfaces of which were subjected to corona discharge treatment were used.

[0016] Comparative Example 1 thickness 0.8 mm, an expansion ratio seven times, having an average diameter of the bubbles in the foam is corona discharge treated on both sides of 25μm low density polyethylene foamed sheet (manufactured by Sekisui Chemical Co., Ltd. Bo Lara IF07008) A molded product adhesive fixing member was obtained in the same manner as in Example 1 except that was used.

[0017] Comparative Example 2 thickness 0.8 mm, an expansion ratio 10 times, corona discharge treatment on both sides of the low-density polyethylene foam sheet the average diameter of 25μm of bubbles in the foam (manufactured by Sekisui Chemical Co., Ltd. Bo Lara IF 1 008) A member for bonding and fixing a molded product was obtained in the same manner as in Example 1 except that the above-mentioned material was used.

Various tests were carried out on the molded product adhesive fixing members obtained in Examples 1 to 3 and Comparative Examples 1 and 2. Table 1 shows the results.

Shape followability A 180 mm long, 25 m wide acrylic plate with a thickness of 3.0 mm
m on one side of the molded product adhesive fixing member, and a 5.0 kg roller one-way pressing a 3.0 mm thick acrylic plate having 100 μm irregularities at 20 mm intervals on the opposite surface of the molded product adhesive fixing member, After 30 days, the retention of the area of adhesion to the recess was measured.

A member for bonding and fixing a molded product having a tensile strength and elongation of 100 mm in length and 10 mm in width is
The tensile tester was installed so that the chuck distance was 50 mm, and 10 mm when pulled at a speed of 300 mm / min.
The strength at the time of 0% stretching (100% modulus), the breaking strength and the breaking elongation were measured.

The adhesive strength moldings adhesive fixing 25mm wide on one side of the lining with 25μm polyester film member, a test piece of length 100 mm, which 2.0kg roller 1 and reciprocation acrylic melamine coated plate, 23 ° C. After standing for 24 hours, the peel resistance was measured when one end of the test piece was peeled in a 180 ° direction at a speed of 50 mm / min.

One side of the high-temperature shear holding force molded product adhesive fixing member was lined with an aluminum foil having a thickness of 100 μm to form a test piece having a width of 25 mm and a length of 100 mm. Has a width of 25 mm and a length of 25
0.5 kg after a 2.0 kg roller reciprocation, a load of 1 kg was applied in the shear direction at 90 ° C., and the time to drop or the displacement distance after 24 hours was measured.

[0023]

[Table 1]

As is evident from Table 1, it can be seen that the molded article bonding and fixing member according to the present invention has excellent shape followability, tensile strength and elongation, adhesive strength and high-temperature shear holding power.

[0025]

According to the present invention, the ability to follow the shape of an uneven surface is greatly improved, and there is no peeling after long-term application.
In addition, it is possible to provide a member for bonding and fixing a molded product with improved adhesive strength.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-91178 (JP, A) JP-A-5-43843 (JP, A) JP-A-64-26692 (JP, A) 15748 (JP, U) Japanese Utility Model Hei 5-46936 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) C09J 7/02

Claims (2)

(57) [Claims] 1. A molded article bonding and fixing member having a foam as a core and pressure-sensitive adhesive layers formed on both surfaces thereof, wherein a major axis extends parallel to the length direction of the core. Characterized in that closed members having a closed elliptical cross section are provided. 2. The member according to claim 1, wherein the ratio of the major axis length to the minor axis length (major axis length / minor axis length) of the closed cells is 1.2 or more.