KR102099538B1 - Dual curing type adhesive tape - Google Patents

Abstract

The present invention relates to a double-curable adhesive tape and, more specifically, to an adhesive tape for protecting and fixing surfaces of various materials. During the first curing before attachment, stable surface protection of an adherend is possible due to the high adhesion. The adhesive force is rapidly reduced when the adhesion is completed and secondarily curing after completion of use, thereby precisely adjust the adhesive force to be easily removed from the adherend.

Description

Dual curing type adhesive tape

The present invention relates to a double-curable adhesive tape. Specifically, the present invention is a pressure-sensitive adhesive tape for protecting and fixing the surfaces of various materials, and during the first curing before attachment, it is possible to secure the surface of the adherend due to high adhesion, and when attached and used, after the second curing The present invention relates to a double-curable adhesive tape capable of precisely adjusting the adhesive force so that the adhesive force is rapidly reduced and is easily removed from the adherend.

The adhesive tape enables adhesion in a short period of time without pressure such as water, solvent, light, heat, etc., even at a pressure such as acupressure, and functions to protect and adhere to the surfaces of various materials such as plastic, wood, and glass.

In order to stably protect the surface of the material, the adhesive tape not only requires physical properties such as adhesion, heat resistance, and chemical resistance, but also needs to control adhesion because it must be removed from the adherend.

If the adhesive strength of the adhesive tape to be removed from the adherend is still maintained, even if the adhesive tape is not easily removed and removed, the adhesive may remain on the surface of the adherend and damage or contaminate the surface of the adherend.

Conventional double-curing adhesive tapes, i.e., adhesive tapes that improve adhesive strength through primary curing prior to attachment to an adherend, and can rapidly decrease adhesive strength through secondary curing after being attached and used, have been used for these purposes, Conventional double-curing adhesive tape has a problem that it is difficult to precisely control the adhesive strength by primary curing and secondary curing.

Therefore, in the adhesive tape that protects and secures the surfaces of various materials, stable adhesion of the adherend is possible due to the high adhesion during the first curing before attachment, and the adhesion rapidly increases during the second curing after being attached and used. There is an urgent need for a double-curable adhesive tape capable of precisely controlling the adhesive force so that it is degraded and easily removed from the adherend.

The present invention is an adhesive tape for protecting and fixing the surface of a material during processing of various materials. In the first curing before attachment, stable surface protection of the adherend is possible due to high adhesion, and is attached and secondary after completion of use. It is an object of the present invention to provide a double-curable adhesive tape capable of precisely controlling the adhesive force so that the adhesive force is rapidly lowered during curing to facilitate removal from the adherend.

In order to solve the above problems, the present invention,

Base layer; And an adhesive layer formed by applying or coating an adhesive composition on one or both surfaces of the base layer, wherein the adhesive composition includes an acrylic adhesive, a curing agent, a UV curable oligomer, and a UV photoinitiator, and based on 100 parts by weight of the acrylic adhesive As, the content of the curing agent is 0.1 to 10 parts by weight, the content of the UV curable oligomer is 2 to 7 parts by weight, the content of the UV photoinitiator is 0.1 to 5 parts by weight, provides a double-curable adhesive tape.

Here, the acrylic pressure-sensitive adhesive includes an acrylic pressure-sensitive adhesive having a weight average molecular weight of 200,000 to 1 million and having a hydroxy (OH) or carboxyl group (COOH) structure, and the curing agent is an isocyanate-based curing agent, an aziridine-based curing agent, and an epoxy-based curing agent. It provides a double-curing adhesive tape, characterized in that it comprises at least one selected from the group consisting of.

In addition, the UV curable oligomer includes an epoxy acrylate-based resin or a polyurethane acrylate-based resin, and the UV photoinitiator comprises at least one UV photoinitiator selected from the group consisting of azo-based photoinitiators, peroxide-based photoinitiators, and acetal-based photoinitiators. It provides a double-curing adhesive tape, characterized in that it comprises.

Furthermore, the UV photoinitiator provides a double-curable adhesive tape, characterized in that it comprises 2,2'-azo-bis-isobutyrylnitrile (AIBN) or benzoyl peroxide (BPO).

On the other hand, the adhesive composition is characterized in that it comprises metal particles of one or more or alloys thereof selected from the group consisting of iron (Fe), silver (Ag), nickel (Ni), copper (Cu) and cobalt (Co) A double curable adhesive tape is provided.

Here, the metal particles, characterized in that it comprises nickel particles having a size of 0.1 to 1 μm, provides a double-curable adhesive tape.

In addition, the adhesive composition is at least one selected from the group consisting of co-marone indene resin (coμmarone indene resin), telpen phenol resin (Terpene phenolic resin), polybutene (polybutene) and hydrogenated rosin ester (Hydrogenated ester of resin) It provides a double-curing adhesive tape, characterized in that it further comprises a tackifier.

In addition, the base layer includes at least one film selected from the group consisting of polyolefin (PO), polyvinyl chloride (PVC) and polyethylene terephthalate (PET) and a UV stabilizer, and the UV stabilizer is the total weight of the base layer Characterized in that it comprises a content of 0.1 to 3% by weight based on, provides a double-curable adhesive tape.

On the other hand, it provides a double-curable adhesive tape, characterized in that the adhesive strength after heat curing and photocuring of the double-curable adhesive tape is reduced to 70% or more based on the adhesive strength after thermal curing.

The double-curable adhesive tape according to the present invention has a high adhesive strength during primary heat curing, so that it is possible to stably protect and fix the surface of the adherend, and after the completion of use, the adhesive strength rapidly decreases during secondary photocuring, so that the adherend It is possible to easily remove from the surface, and by minimizing or avoiding the residual adhesive on the adherend surface after removal, the remaining adhesive exhibits an excellent effect of effectively solving the problem of damaging or contaminating the adherend surface.

Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the embodiments described herein, and may be embodied in other forms. Rather, the embodiments introduced herein can be thoroughly and completely disclosed, and sufficiently convey the spirit of the invention to those skilled in the art. It is provided to make it possible.

The present invention is a pressure-sensitive adhesive tape for protecting and fixing the surface of a material during processing. It is attached while having a high adhesive strength during the first curing before attachment, and the adhesive strength rapidly decreases during secondary curing after use, so it can be easily removed. Accordingly, an object of the present invention is to provide a double-curable pressure-sensitive adhesive tape that can effectively prevent damage or contamination of the adherend surface due to the residual pressure-sensitive adhesive by suppressing the presence of the pressure-sensitive adhesive on the adherend surface.

The double-curable adhesive tape has a thickness of 0.3 to 3 mm and 100 to 700 g in various materials, for example, plastic injection doors, high glossy, stainless steel plates, pre-coated metal, etc. It can be used for the purpose of being easily removed after being attached to the surface of the adherend for a short period of time within 2 months.

Here, the pressure-sensitive adhesive tape attached to the object so that the object does not escape during molding, such as press processing and bending processing, needs to have a high adhesive strength, but after the work is completed, the adhesive strength must be lowered again to be easily removed from the object.

Accordingly, the double-curable adhesive tape according to the present invention includes a film formed of a material such as polyethylene (PE), polypropylene (PP), polyolefin (PO), polyvinyl chloride (PVC), polyethylene terephthalate (PET), etc. It may include a substrate layer, and an adhesive layer formed by applying or coating an adhesive composition on one or both sides of the substrate layer.

In addition, it is preferable to select a color such as transparent color or transparent blue so that the substrate layer can easily undergo photo-curing by ultraviolet irradiation in the adhesive layer. Additionally, an ultraviolet stabilizer is added to prevent photolysis of the base layer from ultraviolet rays. This prevents discoloration of the substrate, surface cracking, deterioration of mechanical properties, etc. by first absorbing ultraviolet rays reaching the substrate layer.

The UV stabilizer may be selected from the group consisting of an UV absorber, a quencher, a peroxide decomposing agent, a radical scavernger, and a HALS (Hindered amine light stabilizer), and the total weight of the base layer Based on, it may be added in an amount of 0.1 to 3% by weight.

The adhesive composition is a component for primary heat curing, and the acrylic adhesive and isocyanate-based, aziridine-based, and epoxy-based adhesives having a weight average molecular weight of 200,000 to 1,000,000 and having a hydroxy (OH) or carboxyl group (COOH) structure A UV photoinitiator that may include a curing agent and has excellent compatibility with the curing agent, such as epoxy acrylate-based resins such as bisphenol A type, polyurethane acrylate-based resins, and the like, as components for secondary photocuring. As a 2,2'- azo-bis-isobutyryl nitrile (AIBN), azo-based, benzoyl peroxide (BPO), such as peroxide-based, acetal-based UV photoinitiators may be included.

Here, based on 100 parts by weight of the acrylic adhesive, the content of the curing agent may be 0.1 to 10 parts by weight, the content of the UV curable oligomer is 2 to 7 parts by weight, the content of the UV photoinitiator may be 0.1 to 5 parts by weight.

When the content of the curing agent is less than 0.1 parts by weight, the adhesive strength may be insufficient after the first heat curing of the double-curable adhesive tape, whereas when it exceeds 10 parts by weight, the adhesive force is excessive and the adhesive is transferred to the surface of the adherend, resulting in an adherend surface. It can be damaged or contaminated.

In addition, when the content of the UV-curable oligomer or the content of the UV photoinitiator is less than the standard, the adhesive strength decrease after secondary photocuring is insufficient, and thus the removal of the adhesive tape may be difficult.

The acrylic pressure-sensitive adhesive and curing agent is a heat curing step, that is, the generation of radicals by heat aging at 60 to 150 ° C is initiated and the degree of crosslinking is increased by a crosslinking reaction, resulting in improved adhesion, after which the pressure-sensitive adhesive is attached to the surface of various materials It plays a role of stably protecting and fixing.

In addition, the UV curable oligomer and UV photoinitiator can be cured when irradiated with UV of 254 to 365 nm to the adhesive layer to form a three-dimensional network structure, and consequently, the fluidity of the acrylic polymer chain included in the acrylic adhesive. By being limited, the adhesive strength of the adhesive layer is greatly reduced, so that the adhesive tape can be easily peeled and removed from the adherend.

On the other hand, the pressure-sensitive adhesive composition may be selected from a liquid or solid at room temperature and a thermoplastic resin having a softening point of 70 to 150 ° C., gumarone-dendene resin, terpene phenolic resin, polybutene ( polybutene) and hydrogenated rosin esters (Hydrogenated ester of resin) may further include additives such as tackifiers or anti-aging agents, modified silicone oils, solvents selected from one or more groups.

And, the pressure-sensitive adhesive composition is iron (Fe), silver (Ag), nickel (Ni), copper (Cu), cobalt (Co) or a metal particle containing an alloy thereof, preferably nickel (Ni) particles It may further include, these metal particles improve the durability of the adhesive layer and perform a function of preventing unintentional curing by natural UV light such as sunlight.

In particular, nickel (Ni) particles can be prepared using a carbonyl decomposition process (Carbonyl Decomposition Process) by a liquid precipitation method and a thermal decomposition method, and have excellent oxidation resistance. There is an additional advantage that does not cause problems such as deterioration of physical properties and discoloration.

The metal particles may have a size of 0.1 to 1 μm in consideration of compatibility with the pressure-sensitive adhesive forming the adhesive layer, wherein the size of the metal particles means the diameter of a sphere converted to have the same volume. In addition, the content of the metal particles may be 0.1 to 5 parts by weight based on 100 parts by weight of the acrylic pressure-sensitive adhesive.

Here, when the content of the metal particles is less than 0.1 parts by weight, the durability of the adhesive layer of the adhesive tape is insufficient, and when stored, the adhesive force may be deteriorated unexpectedly by sunlight or the like, and the adhesive strength may be deteriorated before adhesion, whereas 5 weight In the case of excess, the physical properties of the pressure-sensitive adhesive may be significantly reduced.

As a result, the double-curable adhesive tape according to the present invention retains the adhesive force precisely controlled by the first heat curing before attachment and is attached at the same time. Not only is it easy to remove, but also prevents the adhesive from remaining on the surface of the adherend upon removal, thereby suppressing damage and contamination of the surface of the adherend due to the residual adhesive.

Specifically, the double-curable adhesive tape according to the present invention has an adhesive strength of 50 to 1,000 gf / 25mm realized by primary thermal curing before attachment, and an adhesive strength of lowered by secondary photocuring after completion of use is 1 to 350 gf / It may be 25mm, in particular, the adhesive strength lowered by secondary photocuring may be 2 to 35% of the adhesive strength realized by primary thermal curing.

For example, if the adhesive strength after the first heat curing is 800 to 1000 gf / 25mm, it can be adjusted to the level of 50 to 350 gf / 25mm after the second photocuring, and the adhesive strength after the first heat curing is 500 to 800 gf / In the case of 25mm, it can be adjusted to 20 ~ 250 gf / 25mm level after the second photocuring. In addition, if the adhesive strength after the first heat curing is 200 to 500 gf / 25mm level, it can be adjusted to the level of 10 to 150 gf / 25mm after the second photocuring, and the adhesive strength after the first heat curing level is 50 to 200 gf / 25mm In this case, after the second photocuring, it is possible to adjust the level to 1-50 gf / 25mm. In addition, the adhesive strength after the secondary photocuring can be additionally adjusted depending on the UV irradiation time and the content of the photocurable oligomer.

[Example]

[a] Preparation of adhesive tape

In preparing the adhesive tapes of Examples 1 to 8 below, the adhesive layer is coated on a base film using a coating method such as a comma coating or a gravure coater of the adhesive, and is 20 to 20 at a level of 60 to 150 ° C using a hot air flow type drying duct. After drying in a fast time of 60 seconds, the adhesive tape was manufactured through a aging process for about 24 to 60 hours.

Example 1

100 parts by weight of acrylic adhesive, 1 part by weight of aziridine-based curing agent are mixed, 3 parts by weight of UV oligomer (Bisphenol A epoxy diacrylate), and 1 part by weight of UV initiator AIBN are mixed, and then 0.5 parts by weight of 1 μm nickel powder is diluted in EA to apply the adhesive. The adhesive tape was prepared by coating the adhesive to a 50 μm PE film using a gravure coating method to a dry thickness of 5 μm.

Example 2

After mixing 3 parts by weight of an aziridine-based curing agent with 100 parts by weight of an acrylic adhesive, mixing 5 parts by weight of UV oligomer (Bisphenol A epoxy diacrylate) and 1 part by weight of UV initiator AIBN, and diluting 0.3 parts by weight of 1 μm nickel powder to EA to apply the adhesive. The adhesive tape is prepared by coating the adhesive to a 50 μm PE film using a gravure coating method to a dry thickness of 3 μm.

Example 3

After mixing 0.5 parts by weight of aziridine-based curing agent with 100 parts by weight of acrylic adhesive, mixing 3 parts by weight of UV oligomer (Bisphenol A epoxy diacrylate), and 0.5 parts by weight of UV initiator AIBN, dilute 0.1 parts by weight of 0.5 μm nickel powder to EA and apply adhesive To prepare, the adhesive is coated on a 150 μm PE film using a comma coating method to a dry thickness of 20 μm to prepare an adhesive tape.

Example 4

Mix 0.5 parts by weight of aziridine-based curing agent with 100 parts by weight of acrylic adhesive, mix 5 parts by weight of UV oligomer (Bisphenol A epoxy diacrylate), and 0.5 parts by weight of UV initiator AIBN, and then mix 0.2 parts by weight of 0.5 μm nickel powder to obtain an adhesive. The adhesive tape is prepared by coating the adhesive to a 50 μm PE film using a gravure coating method to a dry thickness of 7 μm.

Example 5

0.3 parts by weight after mixing 5 parts by weight of isocyanate curing agent with 100 parts by weight of acrylic adhesive, 3 parts by weight of UV oligomer (Bisphenol A epoxy diacrylate), 10 parts by weight of tackifier (telpenphenol), and 0.5 parts by weight of UV initiator AIBN To prepare a pressure-sensitive adhesive by mixing 0.5 parts by weight of nickel powder. A tape is prepared by coating a 70 μm PE film with a dry thickness of 5 μm using a gravure coating method.

Example 6

After mixing 3 parts by weight of isocyanate curing agent with 100 parts by weight of acrylic adhesive, 5 parts by weight of UV oligomer (Bisphenol A epoxy diacrylate), 15 parts by weight of tackifier (telfenphenol), 0.3 parts by weight of UV initiator AIBN, and 0.3 To prepare an adhesive by mixing 0.5 parts by weight of nickel powder of μm, and apply the adhesive to a 50 μm PE film using a gravure coating method to prepare a pressure-sensitive adhesive tape with a dry thickness of 5 μm.

Example 7

Mix 100 parts by weight of acrylic adhesive with 3 parts by weight of isocyanate curing agent, 3 parts by weight of UV oligomer (Bisphenol A epoxy diacrylate), 15 parts by weight of tackifier (Telpenphenol), and 0.3 parts by weight of UV initiator AIBN. Prepared, and coated with the adhesive to a 50 μm PE film using a gravure coating method to a dry thickness of 5 μm to prepare an adhesive tape.

Example 8

0.3 parts by weight after mixing 3 parts by weight of isocyanate curing agent with 100 parts by weight of acrylic adhesive, 5 parts by weight of UV oligomer (Bisphenol A epoxy diacrylate), 15 parts by weight of tackifier (Telpenphenol), and 0.3 parts by weight of UV initiator BPO To prepare a pressure-sensitive adhesive by mixing 0.5 parts by weight of the nickel powder, and coating the pressure-sensitive adhesive to a 50 μm PE film with a dry thickness of 5 μm using a gravure coating method to prepare an adhesive tape.

[b] Evaluation of adhesive strength of adhesive tape

According to the adhesive strength test method according to the standard KS T 1028, the adhesive tapes of Examples 1 to 8 were left in a 60 ° C. bath for aging time 24 to 48 hours, subjected to thermal curing, and then attached to the STS304BA specimen, and then 180 at a rate of 300 mm / min. The adhesive force was measured after the first heat curing by measuring the force required to pull in °, and after attaching to the STS304BA specimen, UV is applied for 5 to 20 seconds by using a mercury UV lamp or iron (Fe) -based metal halide lamp with a wavelength of 365 nm. After the irradiation, the adhesive force was measured after the secondary photocuring by measuring the force required by pulling at 180 ° at a speed of 300 mm / min. Measurements were made three times each to calculate the average value, and the evaluation results are shown in Table 1 below.

Hardening method Adhesion (gf / 25mm) 1 time Episode 2 3rd time medium Example 1 Heat curing 256 277 281 271 Photocuring 80 65 54 66 Example 2 Heat curing 145 154 125 141 Photocuring 5 12 7 8 Example 3 Heat curing 555 613 573 580 Photocuring 120 78 143 113 Example 4 Heat curing 344 356 312 337 Photocuring 122 113 89 108 Example 5 Heat curing 211 145 205 187 Photocuring 45 42 38 41 Example 6 Heat curing 277 286 267 276 Photocuring 56 61 45 54 Example 7 Heat curing 377 345 366 362 Photocuring 122 65 111 99 Example 8 Heat curing 289 311 289 296 Photocuring 77 78 67 74

As shown in Table 1, the double-curable adhesive tape prepared in this example exhibited a high adhesive strength of 140 to 580 fg / 25mm when heat-curing, but the primary adhesive strength after photocuring by ultraviolet light. It was reduced to about 70% or more, especially in the case of Example 2, only about 5% of the adhesive strength was realized compared to the heat curing.

That is, the double-curing agent adhesive tape according to the present invention can be more stably protected when attached to a material due to the improvement of the adhesive force during thermal curing by incorporating a thermal curing agent into the acrylic adhesive, and also due to the rapid drop of the adhesive force during UV curing The effect that it can be more easily removed can be realized.

Although this specification has been described with reference to preferred embodiments of the present invention, those skilled in the art variously modify and change the present invention without departing from the spirit and scope of the present invention as set forth in the claims set forth below. You can do it. Therefore, if the modified implementation basically includes the components of the claims of the present invention, it should be considered that all are included in the technical scope of the present invention.

Claims (9)

A double-curing adhesive tape that is attached to the surface of the adherend after heat curing to protect or fix the surface of the adherend, and is photocured after use and removed from the surface of the adherend,
Base layer; And
It includes an adhesive layer formed by applying or coating an adhesive composition on one or both sides of the base layer,
The adhesive composition includes an acrylic adhesive, a curing agent, a UV curable oligomer, a UV photoinitiator, metal particles and a tackifier,
The UV curable oligomer comprises a bisphenol A type epoxy acrylate-based resin,
The metal particles include nickel particles having a size of 0.1 to 1 μm,
The tackifier comprises a telpen phenol resin,
Based on 100 parts by weight of the acrylic adhesive, the content of the curing agent is 0.1 to 10 parts by weight, the content of the UV curable oligomer is 2 to 7 parts by weight, the content of the UV photoinitiator is 0.1 to 5 parts by weight, the content of the metal particles Silver is 0.1 to 5 parts by weight, the content of the tackifier is 10 to 15 parts by weight,
The heat-curing and photo-curing adhesive strength of the double-curing adhesive tape is reduced to 70% or more based on the adhesive strength before photo-curing after thermal curing, the double-curing adhesive tape. According to claim 1,
The acrylic pressure-sensitive adhesive includes an acrylic pressure-sensitive adhesive having a weight average molecular weight of 200,000 to 1 million, and having a hydroxy (OH) or carboxyl group (COOH) structure,
The curing agent is characterized in that it comprises at least one selected from the group consisting of isocyanate-based curing agent, aziridine-based curing agent and epoxy-based curing agent, a double-curable adhesive tape. According to claim 2,
The UV photoinitiator, characterized in that it comprises at least one UV photoinitiator selected from the group consisting of azo-based photoinitiator, peroxide-based photoinitiator and acetal-based photoinitiator, a double-curable adhesive tape. According to claim 3,
The UV photoinitiator is characterized in that it comprises 2,2'- azo-bis-isobutyrylnitrile (AIBN) or benzoyl peroxide (BPO), a double-curable adhesive tape. delete delete delete The method according to any one of claims 1 to 4,
The base layer includes at least one film selected from the group consisting of polyolefin (PO), polyvinyl chloride (PVC) and polyethylene terephthalate (PET) and a UV stabilizer,
The ultraviolet stabilizer is characterized in that it contains a content of 0.1 to 3% by weight based on the total weight of the base layer, double-curable adhesive tape. delete