JPH0694550B2 - Composite adhesive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is capable of firmly adhering to an adherend having an extremely small adhesive area, and has many curved surfaces and irregularities. The present invention relates to a composite pressure-sensitive adhesive body that can be adhered to the surface of the substrate in a state of being in close contact with the surface of the substrate and that can be adhered to the surface of an extremely soft adherend without any damage.

[Prior Art] Conventionally, generally used pressure-sensitive adhesive tapes usually have a pressure-sensitive adhesive layer on the surface of paper, cloth, plastic film or the like. Therefore, such an adhesive tape, when used, is limited in its use depending on the characteristics of the base material, or causes problems due to the characteristics. For example,
When sticking an adhesive tape to an adherend having a net-like structure such as a sieve, since the contact area between the adherend and the adhesive tape is very small, the mutual bonding force becomes weaker, As a result, the adhesive tape is easily peeled off from the adherend.

In addition, when the surface of the adherend is a curved surface or has a complicated shape with many irregularities, there is a problem that it is difficult to adhere the adhesive tape in a close contact state. This problem is prominently exhibited when the adhesive tape is attached to the surface of a small sphere such as a pachinko ball or the surface of an adherend having many irregularities such as a concrete block. This problem can be solved to some extent by using an adhesive tape having a highly stretchable base material, but it is still insufficient, and in this case, it can be applied only to a hard adherend. There is a problem. That is, when the adhesive tape with high elasticity is attached to the adherend in a stretched state, stress is applied in the direction opposite to the stretched direction. A problem that wrinkles and twists occur occurs.

[Problems to be Solved by the Invention] As described above, according to the present invention, in the conventional adhesive tape, when the contact area between the adhesive tape and the adherend is small, the surface of the adherend is curved or uneven. If there are many faces,
Further, the present invention aims to solve the problem that it is difficult to apply the film to the surface of the adherend in a sufficiently soft manner.

[Means for Solving Problems] That is, in the composite pressure-sensitive adhesive body of the present invention, a plastic layer and a pressure-sensitive adhesive layer are laminated in this order on a support, and the plastic layer has plasticity at room temperature. , A layer comprising a monomer, an oligomer, or a polymer which can be cured by irradiation with active energy rays or heating and a mixture thereof and a filler.

The support constituting the composite pressure-sensitive adhesive body of the present invention is for holding the plastic layer and the pressure-sensitive adhesive layer during production and storage of the composite pressure-sensitive adhesive body. Therefore, the material of the support is not particularly limited, and examples thereof include fibrous base materials such as paper, cloth and non-woven fabric, polyethylene, polypropylene, polyester, polyvinyl chloride, cellulose acetate, polycarbonate, cellophane and polyvinylidene fluoride. Alternatively, a sheet or a composite material in which these are combined can be used.

The plastic layer constituting the composite pressure-sensitive adhesive body of the present invention is a layer which has plasticity at room temperature and can be cured by irradiation with active energy rays or by heating, and the plastic layer is essential for achieving the object of the present invention. In addition, after curing, it has the same function as the base material in an ordinary adhesive tape. Such a plastic layer may include active energy rays such as electron beams and X-rays.
It is composed of a monomer, an oligomer or a polymer which can be cured by irradiation with rays such as rays, α rays, β rays, γ rays and ultraviolet rays or by heating, or a mixture thereof, and a filler.

Among the components that can be cured by active energy rays, which are the constituent materials of the plastic layer, the monomer is a monofunctional monomer, such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate. Examples thereof include acrylates such as ethylhexyl (meth) acrylate, and examples of the bifunctional or higher functional monomer include 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate and tetraethylene glycol diacrylate. And triacrylates such as trimethylolpropane tri (meth) acrylate and pentaerythritol tri (meth) acrylate.
More than one species can be used. As the oligomer, for example, one or more oligomers of the above monomers (average molecular weight: 500 to 4000) can be used. As the polymer, for example, a solvent-less, relatively high viscosity (5000 to 50000 cP
s) polyurethane (meth) acrylate resin, specifically, for example, XP-7000B, XP-2000B or XP-4200 (trade name, all manufactured by Nippon Synthetic Chemical Industry Co., Ltd.); diazo group-containing resin, for example , Lithoresin X (manufactured by American Hoechst) epoxy (meth) acrylate resin, for example, epoxy ester M-600A, epoxy ester 80MFA, epoxy ester 40EM and epoxy ester 70PA (all manufactured by Kyoeisha Oil and Fat Chemical Co., Ltd.) You can When ultraviolet rays are used as a means for curing each component, it is preferable to add a catalyst such as a photopolymerization initiator, a photosensitizer or a photoaccelerator.

Further, the component curable by heating is similar to the monomer, oligomer or polymer curable by the above-mentioned active energy ray, or a mixture thereof by adding a thermal polymerization initiator, a thermal sensitizer or a thermal accelerator. Can be used. Whether the plastic layer is an active energy ray-curable type or a thermosetting type can be appropriately determined according to the application of the composite pressure-sensitive adhesive body.

The filler, which is a constituent material of the plastic layer, is a component that contributes to impart plasticity to the thermoplastic layer at room temperature. Such fillers include inorganic extender pigments such as clay, talc, mica, serinite, barium sulfate, silicic acid anhydride, glass beads, glass flakes, abrasive powder, calcium carbonate, calcium sulfate, wollastonite and aluminum hydroxide. Plastic powders such as polyurethane resin fine powder, polyethylene resin fine powder, polyamide resin fine powder and polyvinyl alcohol resin fine powder;
These may be used, and any one of them may be appropriately selected and used.

The mixing ratio of the component curable by active energy rays or heat constituting the plastic layer and the filler is such that the curable component 10
The filler is 10 to 250 parts by weight with respect to 0 parts by weight, preferably
30 to 200 parts by weight. When the amount of the filler is too small, fluidity remains at room temperature, sufficient plasticity cannot be obtained, and a threading phenomenon may occur when the substrate is peeled from the plastic layer. On the other hand, if the amount is too large, when an external force is applied, the plastic layer is cracked, so that the adhesion to the substrate is reduced, or the cured plastic layer is significantly embrittled.

The pressure-sensitive adhesive layer that constitutes the composite pressure-sensitive adhesive body of the present invention is a layer that adheres to an adherend during use. Although such a layer is made of a pressure-sensitive adhesive, any adhesive may be used in this case, and can be appropriately selected according to the purpose. Examples of such an adhesive include known adhesives such as natural rubber, isoprene rubber, styrene-butadiene rubber, styrene-isoprene block polymer, polyisobutylene rubber, and other tackifiers that are rosin-based resins, terpene-based resins, and terpene-phenol-based adhesives. Examples thereof include rubber-based pressure-sensitive adhesives containing resins such as resins and petroleum-based resins; acrylic-based pressure-sensitive adhesives such as (meth) acrylic acid esters.

The composite pressure-sensitive adhesive body of the present invention is composed of the above layers,
The composite pressure-sensitive adhesive body can be produced, for example, by the following method.

First, a predetermined amount of active energy rays or a thermosetting component, a filler and, if necessary, various catalysts are mixed so as to be uniform to prepare a constituent material for the filler layer. The filler layer material is then deposited on a suitable support to a thickness of about 50 .mu.m.
Apply it to about 1 mm. In addition, in this case, the coating material may be dispersed in an organic solvent. Further, the support is not particularly necessary after the composite adhesive is adhered to the adherend, and therefore the support and the plastic layer are bonded with a bonding force that does not cause peeling due to normal storage or movement. It is enough if you do.

As the method for forming the constituent material of the plastic layer on the substrate, in addition to the method of extruding the constituent material of the plastic layer from the fine slits, a usual method, for example, surface coating by a gravure coater, a meer bar, a roll coater, an air knife coater or the like. The method can be applied.

After the plastic layer is formed in this manner, the pressure-sensitive adhesive layer is formed thereon. The pressure-sensitive adhesive layer is formed by a method in which the pressure-sensitive adhesive is applied onto the plastic layer using a knife coater, a reverse roll coater, a gravure coater, a die coater, etc., and then dried. Further, a transfer method may be applied in which an adhesive is applied to release paper, dried, and then bonded to a plastic layer.

In this way, the composite pressure-sensitive adhesive body of the present invention can be obtained, but the pressure-sensitive adhesive body can also have a structure in which release paper is adhered on the pressure-sensitive adhesive layer. The thickness of each of the plastic layer and the pressure-sensitive adhesive layer constituting the composite pressure-sensitive adhesive body of the present invention can be set appropriately according to the application. Further, the ratio of the thickness of the plastic layer to the thickness of the pressure-sensitive adhesive layer can be appropriately set according to the application, but usually the thickness of the plasticity is 1 of the thickness of the pressure-sensitive adhesive layer.
-15 times, preferably 2-10 times. Hereinafter, a method of using the composite pressure-sensitive adhesive body of the present invention will be described. First, the pressure-sensitive adhesive layer of the composite pressure-sensitive adhesive body is attached to the adherend. Then, the adhered composite pressure-sensitive adhesive body is pressed from above the support with a finger or the like. As a result, the pressure-sensitive adhesive layer and the plastic layer of the composite pressure-sensitive adhesive body are deformed according to the shape of the adhered body, and since they are plastic layers, the state after deformation can be maintained as they are. Therefore, even when the adherend has a net-like structure, a curved surface, in particular, a curved surface having a small radius of curvature and unevenness, for example, FIG. The composite pressure-sensitive adhesive body of the present invention is adhered to an adherend having a concave and convex surface, when the composite pressure-sensitive adhesive body is adhered and pressed, and FIG. The adhesive layer and the plastic layer are deformed into a state as shown in (showing a cross-sectional view of the adherend when attached and pressed), and the state after the deformation is maintained as it is. As a result, the contact area between the adherend and the pressure-sensitive adhesive layer can be increased as shown in FIG. 1, and the pressure-sensitive adhesive layer can be adhered to the adherend as shown in FIG. it can. Next, the plastic layer is cured by irradiating with active energy rays or by heating while the support is peeled off or while being adhered. In the case of curing by irradiation with active energy rays, for example, electron rays, X rays, α rays, β rays, γ rays and ultraviolet rays can be used. Irradiation conditions vary depending on the type of active energy ray used and the composition of the plastic layer, but for example, when using an electron beam, the irradiation intensity is
It is about 1 to 20 Mrad. In addition, for example, when using ultraviolet rays, irradiation time of several seconds is usually sufficient under the condition that the irradiation target is placed at a distance of 15 cm vertically below the 1 kW (80 W / cm) high pressure mercury lamp. Is. When curing by heating, it is usually sufficient to heat at a temperature of 100 ° C. or higher for about 10 minutes.

In this way, for example, by hardening the plastic layer while maintaining the state after pasting and pressing as shown in FIG. 1 or FIG. 2, it is possible to firmly adhere to the adherend. . When peeling, one end of the cured plastic layer may be pulled.

INDUSTRIAL APPLICABILITY The composite pressure-sensitive adhesive body of the present invention can be applied not only as an ordinary pressure-sensitive adhesive body, but also as a masking tape for coating an object having a complicated shape and a molding or reinforcement of an article having a complicated shape. .

[Examples] Hereinafter, the present invention will be described with reference to Examples. In the examples, all "parts" represent "parts by weight".

Example 1 Polyurethane acrylate resin XP-7000B (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) 50 parts 2-hydroxyethyl methacrylate 20 parts Aerosil R-972 (manufactured by Nippon Aerosil Co., Ltd.) 30 parts Irgacure 651 (manufactured by Ciba Geigy) 3 Parts The above components were uniformly mixed to obtain a constituent material for the plastic layer. Then, the constituent material was spread on a 25 μm-thick polyethylene terephthalate film (15 × 20 cm) with a roller to a thickness of about 500 μm to form a plastic layer. Then, on the plastic layer, apply it on release paper,
A dry acrylic pressure-sensitive adhesive (40 μm in thickness after drying) was transferred to obtain a composite pressure-sensitive adhesive sheet.

Then, after sticking the obtained adhesive sheet cut to a width of 12.5 mm to the teeth of the comb, and then pressing it with a finger, the adhesive layer and the plastic layer of the adhesive sheet penetrate into the space between the teeth of the comb. , Fit closely along the tooth mold. Then, in that state, ultraviolet rays were irradiated from above the polyethylene terephthalate film of the pressure-sensitive adhesive sheet for 3 seconds from a distance of 10 cm by a 1 kw high-voltage mercury lamp. As a result, the plastic layer was completely cured and lost its plasticity. In addition, when one end of the cured plastic layer was pulled with a finger, a considerable force (1050 g / 300 mm / min) was required, but the thermoplastic layer did not break, and the adhesive also applied to the comb teeth. Did not remain at all. In addition, a comb tooth pattern was clearly recognized in the plastic layer after peeling.

Comparative Example 1 On a polyethylene terephthalate film having a thickness of 25 μ,
The same pressure-sensitive adhesive as in Example 1 was applied and dried (thickness of the pressure-sensitive adhesive layer after drying was 40 μm) to obtain a pressure-sensitive adhesive tape for comparison. The obtained adhesive tape was attached to the teeth of a comb in the same manner as in Example 1, but the film of the base material hardly penetrated into the teeth of the comb. Further, the force required for peeling the adhesive tape was about 1/4 or less of that in the case of Example 1.

Example 2 Polyurethane acrylate resin XP-2000B (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) 50 parts Polyurethane resin fine powder having a maximum spherical diameter of 40 μ (manufactured by Ohashi Chemical Industry Co., Ltd.) 60 parts Darocur 1173 (manufactured by Merck) 4 parts The above components were uniformly mixed to obtain a constituent material for the plastic layer. Then, the constituent material was spread on a 40 μm-thick polypropylene film (15 × 20 cm) with a roller to a thickness of about 1 mm to form a plastic layer. Further, an adhesive layer was formed on the plastic layer in the same manner as in Example 1 to obtain a composite adhesive sheet.

The obtained pressure-sensitive adhesive sheet was attached on a wire mesh of 150 mesh and pressed with a finger, and the pressure-sensitive adhesive layer and the plastic layer of the pressure-sensitive adhesive sheet penetrated into the stitches. Then, after peeling off the polypropylene film, ultraviolet rays were irradiated in the same manner as in Example 1. As a result, the plastic layer was changed to a cured product having elasticity and the plasticity was lost. When one end of the thus cured plastic layer was pulled with a finger, a considerable force was required, but the plasticity could be peeled off without breaking, and no adhesive remained on the wire mesh. In addition, a clear mesh pattern was observed in the plastic layer after peeling.

Comparative Example 2 The pressure-sensitive adhesive tape obtained in Comparative Example 1 was adhered to the same 150-mesh wire mesh as in Example 2, but the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape slightly penetrates the mesh and is easily peeled off. I was able to.

Example 3 Polyurethane acrylate A-5 (Kyowa Fermentation Co., Ltd.)
50 parts Talc 100 parts Darocur 1173 (manufactured by Merck & Co., Inc.) 2 parts The above components were uniformly mixed to obtain a constituent material for the plastic layer. Then, the constituent material was spread on a polyethylene film (15 × 20 cm) having a thickness of 40 μ so as to have a thickness of 500 μ by a roller to form a plastic layer. further,
A pressure-sensitive adhesive layer was formed on the plastic layer in the same manner as in Example 1 to obtain a composite pressure-sensitive adhesive sheet.

When the obtained pressure-sensitive adhesive sheet was attached to the surface of a glass sphere having a diameter of 5 cm, it was possible to attach it in a closely adhered state. Then, after peeling off the polyethylene film, Example 1
Ultraviolet rays were irradiated in the same manner as in. As a result, the plastic layer was completely cured and the plasticity was lost. Further, when one end of the thus cured plastic layer was pulled with a finger, a considerable force was required, but the plastic layer could be peeled without breaking, and no adhesive remained. Furthermore, the plastic layer after peeling maintained the curved shape of the glass sphere.

Comparative Example 3 The adhesive tape obtained in Comparative Example 1 was attempted to be adhered to the glass sphere of Example 3, but both ends in the width direction of the tape were left over, and as a result, the adhesive tape was adhered to the spherical surface. I couldn't.

[Effects of the Invention] As described above, the composite pressure-sensitive adhesive body of the present invention has the pressure-sensitive adhesive layer and the plastic layer constituting the composite pressure-sensitive adhesive, which are formed on the surface of the adherend when the composite pressure-sensitive adhesive body is adhered to the adherend and pressed. Deform according to the shape, and can retain the shape after deformation;
Also, by curing the plastic layer, it is possible to firmly bond while maintaining the shape after attachment and pressing, which is excellent.

Therefore, by using the composite pressure-sensitive adhesive body of the present invention,
It was difficult to adhere firmly and closely with the conventional adhesive tape. For example, an adherend having a mesh structure, an adherend having a curved surface, particularly a curved surface having a small radius of curvature, and an adherend having an uneven surface. For example, it is now possible to adhere firmly and firmly. Further, even when the surface of the adherend is soft, the surface of the adherend is not distorted during sticking.

[Brief description of drawings]

FIG. 1 and FIG. 2 are diagrams for explaining examples of use of the composite pressure-sensitive adhesive body of the present invention.

Claims (1)

[Claims] 1. A plastic layer and a pressure-sensitive adhesive layer are laminated in this order on a support, and the plastic layer has plasticity at room temperature and is cured by irradiation with active energy rays or heating. A composite pressure-sensitive adhesive body, which is a layer composed of a possible monomer, oligomer, or polymer, or a mixture thereof and a filler.