JP3506467B2 - Double-sided adhesive tape and object to be regenerated - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-sided adhesive tape, and more particularly to a double-sided adhesive tape capable of recovering and reusing a styrene component.

[0002]

2. Description of the Related Art In recent years, recycling of materials has been progressing in the fields of office automation equipment and home appliances. For example, since the main body of a TV or the like is made of polystyrene, by making external accessories such as a nameplate from polystyrene, the main body of a used TV or the like can be attached with the external accessories.
After crushing and melting by heating to a temperature higher than the melting point of polystyrene, molding by a general method such as extrusion molding,
Attempts have been made to cut this and recover and reuse pelletized polystyrene.

[0003]

However, the external accessories such as the above-mentioned nameplates are used for the main body of a TV or the like by a double-sided adhesive tape in which an adhesive layer such as an acrylic adhesive is formed on a substrate made of non-woven fabric or polyester. Is glued to. In the regeneration of the polystyrene, the non-woven fabric or the substrate such as polyester does not melt when the polystyrene melts, and
Since the particles are not dispersed uniformly, the surrounding polystyrene is entrained during molding to become a solidified foreign matter, which hinders the production of the regenerated pellet polystyrene. Therefore, it has been attempted to remove the above-mentioned double-sided adhesive tape together with an adhesive and to regenerate only the main body, but it takes time to remove the base material, and it is impossible to completely remove the base material due to damage or the like. Have difficulty. Also, for example, there is a double-sided adhesive tape that is configured so that the adhesive strength of each adhesive layer is adjusted so that the double-sided adhesive tape remains on the external accessory side. There is a problem that adhesion reliability is poor when bonding to a TV or the like.

It is an object of the present invention to solve the above problems and provide a double-sided adhesive tape capable of recovering and reusing a styrene component even if the base material of the double-sided adhesive tape remains on the object to be reproduced. And

[0005]

The double-sided adhesive tape of the present invention comprises an adhesive layer formed on both sides of a polystyrene base material, and the total styrene content in the base material and the adhesive layer is 15% by weight or more. Is characterized in that. In the present invention, the adhesive layer preferably contains a styrene component, and more preferably the adhesive layer is formed of a pressure-sensitive adhesive at room temperature, or heat. It is formed of an adhesive agent.
The present invention is listed below. (1) Styrene while attached to the polystyrene playback object
A double-sided adhesive tape that is used for the recovery or reuse of
The styrene component is contained on both sides of the polystyrene base material.
An adhesive layer for forming the base material and the adhesive layer
Content of all styrene components in is 15% by weight or more
Double-sided adhesive tape. (2) The adhesive layer is made of pressure sensitive adhesive at room temperature.
The double-sided adhesive tape according to (1) above, which is produced. (3) Adhesive layer formed of a heat-adhesive adhesive
The double-sided adhesive tape according to (1) or (2) above, which is (4) With the double-sided adhesive tape attached, turn the styrene component
It is a regenerated material made of polystyrene to be collected or reused.
The double-sided adhesive tape is a
The adhesive layer containing the styrene component
The total styrene component content in the base material and adhesive layer.
A polystyrene regenerated material having an amount of 15% by weight or more. (5) In addition to the object to be reproduced being an OA device or a home electric appliance
The regenerated body made of polystyrene according to item (4). (6) The object to be reproduced is an accessory for OA equipment or home electric appliances
The regenerated object made of polystyrene according to (4) above.

The double-sided adhesive tape of the present invention will be described in more detail below. The double-sided adhesive tape of the present invention,
Use of polystyrene as the base material, and the total styrene component of the base material and the adhesive layers formed on both surfaces of the base material is 15% by weight or more, preferably 30% by weight or more of the double-sided adhesive tape, More preferably, the content is 40% by weight or more. As the polystyrene base material, a film-shaped body, a sheet-shaped body or the like can be preferably used, and the thickness thereof is usually 10 to 75 μm, preferably 2
It is 5 to 50 μm.

As an adhesive for forming an adhesive layer on both surfaces of the polystyrene base material, for example, an acrylic adhesive, a natural rubber adhesive, a synthetic rubber adhesive, or a polyester adhesive used for a double-sided adhesive tape is used. Although such known adhesives can be used as they are, synthetic rubber adhesives containing a styrene component, especially styrene-isoprene-styrene rubber (SIS), styrene-butadiene-styrene rubber (SBS), styrene-ethylene- Adhesives based on styrene-rich polymers such as butylene-styrene rubber (SEBS) are preferred as they allow the recovery of high quality pelleted polystyrene. In the present invention, the above adhesive may be blended with conventional additives such as tackifier, anti-aging agent and crosslinking agent, if necessary.

The adhesive layer of the double-sided adhesive tape is formed by sticking an adhesive film separately prepared with the above-mentioned adhesive to the base material or by applying the above-mentioned adhesive. At this time, the same adhesive layer may be formed on both surfaces of the base material, or two different adhesive layers may be formed on each surface of the base material. The thickness of the adhesive layer is 10 to 100 μm.
m, preferably about 20 to 80 μm, and both surfaces may have the same thickness or different thicknesses in the present invention.

In the present invention, as the kind of the above-mentioned adhesive, either a pressure-sensitive type adhesive or a heat-adhesive type adhesive can be used. In consideration of the fact that polystyrene is used as the base material and the heat resistance of the adhesive itself, the pressure sensitive type of the adhesive is preferable.

In the present invention, when the adhesive is a pressure sensitive type, the styrene content in the adhesive is 40% by weight.
If it exceeds, even if various additives are used together, sufficient adhesive strength cannot be obtained at room temperature. Therefore, the styrene content is about 10 to 40% by weight, preferably 10 to 30% by weight. In the case of this pressure-sensitive type adhesive, the content of all styrene components of the double-sided adhesive tape is 15 to 90% by weight of all components in consideration of the thickness of the base material and the thickness of the adhesive layer.
Therefore, the regenerated pellet polystyrene can be preferably produced by directly regenerating it.

On the other hand, when the adhesive is a heat-adhesive type,
Unlike the pressure-sensitive type, there is no particular problem if the polystyrene content in the adhesive exceeds 40% by weight, and the polystyrene content is 10-70% by weight, preferably 30%.
About 60% by weight is suitable. Therefore, this heat-bonding type adhesive has a higher content of total styrene components in the double-sided adhesive tape than the pressure-sensitive type adhesive, so that a higher quality regenerated pelletized polystyrene can be produced.

As described above, regeneration of polystyrene is carried out by a general method such as extrusion molding after crushing a material to be regenerated and heating and melting it at a temperature higher than the melting point of polystyrene. In the present invention, the double-sided adhesive tape is used. It is preferable to use a polystyrene film or sheet as the base material of
At that time, the content of the insoluble component is greatly reduced at the melting temperature of the polystyrene, and the dispersibility of the insoluble component is improved. Therefore, even if insoluble components are present,
It does not affect the regeneration of polystyrene. Incidentally, the polystyrene film or sheet,
Usually, SBS, an antioxidant, an ultraviolet absorber, a stabilizer and the like are added to impart flexibility and prevent deterioration, so that the polystyrene content is about 90 to 97% by weight.

In the present invention, for example, polystyrene 9
Even a double-sided adhesive tape in which an acrylic adhesive layer is formed on a substrate composed of a film or sheet of 5% by weight,
From the relationship between the thickness of the adhesive layer and the thickness of the base material, it is effective if the content of all polystyrene components is 15% by weight or more. Specifically, when a polystyrene film having a thickness of 10 μm is used and an acrylic adhesive layer having a thickness of about 30 μm is formed on both surfaces thereof, the polystyrene content of the double-sided adhesive tape has a specific gravity of 1.0.
5. If the specific gravity of the adhesive is 0.9, the total polystyrene content in the double-sided adhesive tape will be 18.3% by weight, so that recycled polystyrene can be suitably produced even if this double-sided adhesive tape is recycled as it is. is there.

[0014]

With the above double-sided adhesive tape, since the polystyrene film or sheet is used as the base material of the double-sided adhesive tape and the total styrene content of the double-sided adhesive tape is 15% by weight or more, When polystyrene is regenerated from the adhesive tape, the base material melts at the melting temperature of the polystyrene. Therefore, the content of the insoluble component is significantly reduced, and the dispersibility of the insoluble component is improved.Therefore, even if the insoluble component is present, the proportion thereof is a trace amount and affects the production of the regenerated pelletized polystyrene. There will be nothing. Therefore, a double-sided adhesive tape having an acrylic adhesive layer is used for adhesion of external accessories, and even if the double-sided adhesive tape remains on the object to be reproduced, it does not hinder the production of regenerated pellet polystyrene, The regenerated pellet polystyrene is preferably recovered from the regenerated body and can be reused.

[0015]

EXAMPLES Hereinafter, the present invention will be described more specifically by showing examples. The present invention is not limited to these examples. [Preparation of adhesive (a)] 100 parts by weight of SIS (trade name JSR-5500 manufactured by Japan Synthetic Rubber; styrene content 14% by weight), petroleum-based resin (trade name: Quinton N-190 manufactured by Nippon Zeon Co., Ltd.) 90 parts by weight , 10 parts by weight of a terpene-based softening agent (trade name YS resin TOL manufactured by Yasuhara Chemical Co., Ltd.) and 1 part by weight of an anti-aging agent (trade name Irganox 1010 manufactured by Ciba Geigy Co., Ltd.) were sufficiently mixed to prepare an adhesive (a). did.

[Preparation of adhesive (b)] SBS (trade name TR
1101 Zeon Corporation; styrene content 30% by weight) 10
0 parts by weight, styrene resin (trade name Picolastic-D1
25 Adhesive (b) was prepared by sufficiently mixing 80 parts by weight of Rika Hercules Co., Ltd.) and 1 part by weight of an antioxidant (trade name Irganox 1010 manufactured by Ciba Geigy).

[Preparation of adhesive (c)] SBS (trade name TR
1101 Zeon Corporation; styrene content 30% by weight) 10
0 parts by weight, 100 parts by weight of a petroleum resin (trade name Alcon M-100 manufactured by Arakawa Chemical Co., Ltd.) and 1 part by weight of an antiaging agent (trade name Irganox 1010 manufactured by Ciba Geigy) are thoroughly mixed to obtain an adhesive (c ) Was prepared.

Examples 1 to 3 Each of the above adhesives (a) to (c) was bar-coated on a release paper and dried at 110 ° C. for 3 minutes to give a dry film thickness of 4 respectively.
A 0 μm adhesive film was prepared. The above adhesive film was laminated on both surfaces of a 40 μm-thick polystyrene film (95%) with a lamination heating roll to prepare three types of double-sided adhesive tape.

Comparative Example 1 A commercially available acrylic pressure-sensitive adhesive having a thickness of 40 μm was formed on both sides of the same 40 μm-thick polystyrene film as in the above-mentioned Example by a roll coater.

Comparative Example 2 The same acrylic adhesive as in Comparative Example 1 was formed on both surfaces of a 40 μm thick non-woven fabric by a roll coater to a thickness of 40 μm.

Using the double-sided adhesive tapes prepared in Examples 1 to 3 and Comparative Examples 1 and 2 , the following adhesion test and recycling test were conducted. As a result, the results are shown in Table 1. The styrene content in Table 1 was calculated with the specific gravity of polystyrene being 1.05 and the specific gravity of the adhesive being 0.9. In the 180 ° C peeling test, PET film # 25 was lined on each of the above-mentioned double-sided adhesive tapes, adhered to a stainless steel plate, and then the adhesive force was measured when peeling at 180 ° C at a pulling speed of 300 mm / min. The recyclability test is
Each of the above double-sided adhesive tapes was adhered to a polystyrene plate in a weight ratio of polystyrene plate / double-sided adhesive tape = 100: 3, which was crushed and melted, then extruded by an extruder and further biaxially stretched. A film having a width of 100 μm was produced and the recyclability was evaluated by the presence of foreign matter in the film.

[0022]

[Table 1]

[0023]

The double-sided adhesive tape of the present invention uses a polystyrene film or sheet as the base material of the double-sided adhesive tape, and the total styrene content of the double-sided adhesive tape is 15% by weight or more. When polystyrene is regenerated from the adhesive tape, the content of the insoluble component is significantly reduced and the dispersibility of the insoluble component is improved. Therefore, even if the insoluble component is present, the proportion thereof is so small that it does not affect the production of the polystyrene pellet. Thus, the double-sided adhesive tape of the present invention does not hinder the production of regenerated pellet polystyrene, even when the double-sided adhesive tape remains on the regenerated body, and is preferably regenerated pelletized polystyrene from the regenerated body. Are collected and can be reused.

─────────────────────────────────────────────────── ─── Continuation of front page (72) Yoshikazu Soeda, 1-2, Shimohozumi, Ibaraki City, Osaka Prefecture Nitto Denko Corporation (72) Naoki Matsuoka, 1-2-1, Shimohozumi, Ibaraki City, Osaka Prefecture No. Nitto Denko Corporation (56) Reference JP-A-4-314776 (JP, A) JP-A-5-179218 (JP, A) JP-A-62-181378 (JP, A) JP-A-52-1 132044 (JP, A) Actual development Sho 53-160464 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) C09J 7/02 C07C 15/46

Claims (4)

(57) [Claims] 1. A polystyrene object to be recovered for reuse or recovery of a styrene component with the double-sided adhesive tape attached, wherein the double-sided adhesive tape comprises a styrene component on both sides of a polystyrene substrate. A material to be regenerated made of polystyrene, in which an agent layer is formed, and the content of all styrene components in the base material and the adhesive layer is 15% by weight or more. Wherein該被regeneration body, polystyrene of the reproduction of claim 1, wherein the OA equipment or home appliances. Wherein該被regeneration body, polystyrene of the reproduction of claim 1, wherein the OA equipment or home appliances accessories. 4. A synthesis wherein the adhesive layer of the double-sided adhesive tape is based on styrene-isoprene-styrene rubber (SIS), styrene-butadiene-styrene rubber (SBS) or styrene-ethylene-butylene-styrene rubber (SEBS). It is formed of a rubber adhesive.
1. The regenerated object made of polystyrene according to 1 .