JPH07228858A - Washable pressure-sensitive adhesive and tacky product - Google Patents

Abstract

PURPOSE:To obtain the subject adhesive, applicable without using a solvent or a solvent medium, readily washable with water and recovering the tack after drying even when washed with water by reacting a radiation curing resin with a specific polyglycol compound according to exposure to radiation. CONSTITUTION:This adhesive comprises a polymer, composed of (A) a radiation curing resin and (B) a polyethylene glycol compound having a cross-linked structure and obtained by reacting the components according to exposure to radiation. Furthermore, the component (B) is the polyethylene glycol compound, prepared by reacting (i) polyethylene glycol with (ii) any one or more of a polyvalent carboxylic acid (anhydride), a lower alkyl ester of the polyvalent carboxylic acid and a polyvalent isocyanate and finely pulverized to preferably <=100mum particle diameter. The component (B) is used in an amount of preferably 0.5-100 pts.wt. based on 100 pts.wt. component (A) and (C) an organic or an inorganic pigment having 1-20mum average particle diameter is used in an amount of preferably 0.5-100 pts.wt. based on 100 pts.wt. total amount of the components (A) and (B).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a radiation-curable pressure-sensitive adhesive composition which does not require water or a solvent as a solvent or a dispersion medium. More specifically, the present invention relates to a washable pressure-sensitive adhesive which can be peeled off by washing with water and has tackiness after drying, and a pressure-sensitive adhesive product thereof.

[0002]

2. Description of the Related Art Conventionally, pressure-sensitive adhesives (adhesives) have been used as industrial tapes, masking tapes, packing tapes, packing tapes, distribution labels, product price labels, display labels, medical tapes, stickers, toys, and other stationery. It is used in many fields such as tapes. In recent years, it has also been used in the fields of sole mats placed at the entrance of clean rooms, adhesive rolls for cleaning carpets and carpets, and simple adhesive rolls for removing dust from clothes and OA equipment. The adhesiveness or tackiness required for pressure-sensitive adhesives is almost the same level as adhesives,
Wide range of temporary adhesive properties such as those found on adhesive sticky notes.

Generally, conventional adhesive products are rarely peeled off after being used for adhesion once, and such applications are limited to a limited field such as masking tape and adhesive sticky notes. . Even these pressure-sensitive adhesive products for peeling are generally disposable, and the pressure-sensitive adhesive products once adhered and peeled are rarely reused again.
For this reason, a pressure-sensitive adhesive or a pressure-sensitive adhesive composition made for the purpose of repeated reuse has not been obtained by a conventional method.

Conventional pressure-sensitive adhesives are mainly composed of natural or synthetic polymers to which tackifiers, cross-linking agents, softening agents and fillers are added, and these are used in water, alcohol, ethyl acetate, toluene and the like. It is dissolved or dispersed in an organic solvent to form a liquid, coated on a support such as paper or film, dried and used as a pressure-sensitive adhesive layer. In addition to this, there is a hot-melt type pressure-sensitive adhesive in which a polymer which is originally solid is melted at a high temperature, directly applied to a support, cooled and solidified to form a pressure-sensitive adhesive layer. In the former method, when a porous support such as paper is used, it is essential to provide a barrier layer or an undercoat layer in order to prevent the pressure sensitive adhesive from penetrating into the support. Not only a great amount of energy is used for drying the solvent and melting the pressure-sensitive adhesive, but also for the synthetic resin sheet having a low softening point due to the heating step for the support, or the heat-sensitive paper that develops heat-sensitive color. Direct processing was impossible. Further, as the product is gradually crosslinked due to the influence of the crosslinking agent contained in the pressure sensitive adhesive, or the solvent remaining in the pressure sensitive adhesive layer or the adhesive property is changed due to the solvent being gradually lost. There was a problem that the stability over time was not sufficient.

In addition to conventional pressure-sensitive adhesives using solvents, pressure-sensitive adhesives that are polymerized and crosslinked by irradiation with radiation such as ultraviolet rays or electron beams have also been researched and developed. If the radiation dose is excessive, polymerization of the pressure-sensitive adhesive will proceed too much and the adhesive performance will be extremely reduced. If the polymerization is carried out to the extent that it has an appropriate adhesive performance, it is prepared. There has been a problem that the change with time after that is remarkable, and that the adhesive performance is deteriorated after a certain period of time has elapsed since the preparation. Generally, radiation-curable resins include hydroquinone monomethyl ether and phenothiazine-based compounds as polymerization inhibitors, but the compounds already present before irradiation lose their polymerization preventing function by irradiation with radiation,
Alternatively, it has a problem that it is colored over time, which is insufficient for solving the above-mentioned problems.

[0006]

Therefore, the problem to be solved by the present invention is that it can be applied without solvent and without solvent, and it is cured by irradiation with radiation to develop the necessary tackiness,
Even if the obtained pressure-sensitive adhesive layer is exposed to the air, it does not dry for a long period of time and is excellent in stability over time without deterioration.
The present invention relates to a pressure-sensitive adhesive which is a raw material for a pressure-sensitive adhesive product which is easy to wash adherends and contaminants adhering to the surface with water, and has tackiness again after drying even if washed with water. Furthermore, by inactivating the unreacted radical species trapped in the resin composition after curing by irradiation with radiation,
The present invention relates to a pressure-sensitive adhesive and a pressure-sensitive adhesive which is a raw material for the pressure-sensitive adhesive product, in which deterioration of the pressure-sensitive adhesive performance with time is significantly improved by preventing the progress of polymerization of the radiation curable resin with time.

[0007]

As a result of intensive studies on means for solving the above problems, the inventors of the present invention have invented the washable pressure-sensitive adhesive and tacky product of the present invention.
That is, a pressure-sensitive adhesive characterized in that (1) a radiation-curable resin and (2) a polyethylene glycol compound having a cross-linking structure are contained as a main component of a polymer obtained by reaction by irradiation with radiation. It is an invention.

The polyethylene glycol compound having the crosslinked structure is one or more compounds selected from the group consisting of polyethylene glycol, polyvalent carboxylic acid, polyvalent carboxylic acid anhydride, polyvalent carboxylic acid lower alkyl ester, and polyvalent isocyanate. It is preferably a polyethylene glycol compound obtained by reacting with. Furthermore, the polyethylene glycol compound having the crosslinked structure has a particle size of 10
It is preferably finely pulverized to 0 μm or less.

In the pressure sensitive adhesive, the weight ratio of the radiation curable resin to the polyethylene glycol compound having a crosslinked structure is 0.5 to 100 parts by weight of the polyethylene glycol compound with respect to 100 parts by weight of the radiation curable resin.
It is preferably a part by weight ratio.

Further, 0.5 to 100 parts by weight of an organic or inorganic pigment having an average particle size of 1 to 20 μm may be contained with respect to 100 parts by weight of the total amount of the radiation curable resin and the polyethylene glycol compound having a crosslinked structure. preferable.

In the pressure-sensitive adhesive, a resin composition comprising a radiation curable resin and a polyethylene glycol compound having a crosslinked structure is polymerized by irradiation with radiation, and then the resin composition is treated with a radical polymerization inhibitor. Is desirable.

Furthermore, in a pressure-sensitive adhesive product having a pressure-sensitive adhesive layer on at least one surface of a support, the pressure-sensitive adhesive layer comprises (1) 100 parts by weight of a radiation-curable resin and (2) a polyethylene glycol having a crosslinked structure. Compound 0.5-
The invention is an invention of an adhesive product obtained by curing a pressure-sensitive adhesive composition containing 100 parts by weight as a main component by irradiation with radiation, wherein the pressure-sensitive adhesive composition is polymerized by irradiation with radiation, and then the pressure-sensitive adhesive is polymerized. The adhesive composition is preferably treated with a radical polymerization inhibitor.

In the present invention, it is preferable to use an electron beam or an ultraviolet ray as the radiation.

Hereinafter, the washable pressure-sensitive adhesive obtained by the present invention will be referred to as "washable pressure-sensitive adhesive" and will be described in detail. The present invention relates to an electron beam-curable pressure-sensitive adhesive composition that does not require water or a solvent as a solvent or a dispersion medium, and a pressure-sensitive adhesive obtained by curing by electron beam irradiation is required at the time of curing. It has excellent adhesiveness, and even if the pressure-sensitive adhesive layer is exposed to the air, it does not dry and deteriorate for a long period of time, and it is possible to peel off the adherend by washing with water,
Alternatively, the present invention relates to a pressure-sensitive adhesive which can be cleaned of contaminants adhering to its surface and has tackiness after drying, and a pressure-sensitive adhesive composition as a raw material thereof.

The washable pressure-sensitive adhesive of the present invention is characterized by being cured by irradiation with radiation, and the main part of its composition is composed of a radiation-curable resin and a polyethylene glycol compound having a crosslinked structure.

Examples of the radiation curable resin used in the present invention include compounds having an ethylenically unsaturated bond, which can be roughly classified as follows regardless of the number of polymerizable functional groups. (1) Aliphatic, alicyclic, aromatic, araliphatic polyhydric alcohol and (meth) acrylate of (poly) alkylene glycol (2) Aliphatic, alicyclic, aromatic, araliphatic polyhydric (Meth) acrylate of polyhydric alcohol obtained by adding alkylene oxide to alcohol (3) (Poly) ester (meth) acrylate (4) (Poly) urethane (meth) acrylate (5) Epoxy (meth) acrylate (6) ( Poly) amide (meth) acrylate (7) (meth) acryloyloxyalkyl phosphate and its salt (8) Vinyl- or diene-based compound having a (meth) acryloyloxy group at the side chain or terminal (9) Monofunctional (Meth) acrylate, N-vinylpyrrolidone, N-vinylformamide, (meth) acryloyl compound (10 Cyano compound having ethylenically unsaturated bond (11) Mono- or polycarboxylic acid having ethylenically unsaturated bond, and their alkali metal salts, ammonium salts, amine salts, etc. (12) Vinyl lactam and polyvinyl lactam compound (13) Acrylamide compound (14) (Poly) ether having ethylenically unsaturated bond and its ester (15) Alcohol ester having ethylenically unsaturated bond (16) Polyalcohol having ethylenically unsaturated bond and its ester (17) Aromatic compounds having one or more ethylenically unsaturated bonds such as styrene and divinylbenzene (18) (Poly) organosiloxane compounds having a (meth) acryloyloxy group at the side chain or terminal (19) Ethylenically unsaturated Having a bond Corn Compound (20) amino modified, or carbamate-modified (meth) acrylate (21) (1) to (20) multimeric or oligoester (meth) acrylate modified compounds of the compounds described

The polyethylene glycol compound having a crosslinked structure used in the present invention (sometimes referred to as polyethylene oxide compound) is a polyethylene glycol compound, a polyvalent carboxylic acid, a polyvalent carboxylic acid anhydride, and a polyvalent carboxylic acid lower alkyl. It is obtained by reacting with one or more compounds selected from the group of esters and polyisocyanates. Hereinafter, the polyethylene glycol compound having a crosslinked structure is simply referred to as a crosslinked polyethylene glycol compound. When the polyvalent carboxylic acid, polyvalent carboxylic acid anhydride, polyvalent carboxylic acid lower alkyl ester, and polyvalent isocyanate are divalent carboxylic acid, divalent carboxylic acid anhydride, divalent carboxylic acid lower alkyl ester, and divalent isocyanate, respectively In addition, since the polyethylene glycol compound obtained by the reaction may be a linear polymer having a skeleton such as divalent carboxylic acid as a center or a relay, a cross-linking agent may be mixed in the reaction system, Alternatively, it is preferable to use the polyethylene glycol compound after irradiating it with an electron beam or γ-ray to crosslink it.

The polyethylene glycol compound is an organic compound having two active hydrogen groups, for example, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol. , Bisphenol A, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, aniline, butylamine, octylamine, laurylamine, hexylamine and the like are used as raw materials to polymerize ethylene oxide.

The ethylene oxide used for the polymerization may optionally contain other alkylene oxides, namely propylene oxide, 1,2-epoxybutane, 1,2-epoxypentane, 1,2-epoxyheptane, 1,2-.
It is also possible to use a mixture of α-olefin oxide such as epoxy octane and 1,2-epoxy nonane, styrene oxide, glycidyl ether and the like. The amount of ethylene oxide contained in all alkylene oxides is preferably 80% or more in terms of molar ratio.

In the present invention, specific examples of the polyvalent carboxylic acid or its anhydride, or its lower alkyl ester, and the polyvalent isocyanate reacted with the polyethylene glycol compound include, for example, malonic acid, succinic acid, maleic acid, Fumaric acid, adipic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, itaconic acid, trimellitic acid, pyromellitic acid, 7,12-dimethyl-7,11-octadecadiene-1,18-dicarboxylic acid, 7,12-Dimethyl-octadecane-1,18
-Dicarboxylic acids or their dimer acids, etc., or their acid anhydrides, or their mono- or di-methyl esters, mono- or di-ethyl esters, mono- or di-propyl esters, etc., trimethylhexamethylene diisocyanate, Tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, tolidine diisocyanate, isophorone diisocyanate, dicyclohexyl diisocyanate, naphthalene diisocyanate and the like.

The cross-linked polyethylene glycol compound of the present invention means a polyethylene glycol compound, a polyvalent carboxylic acid or its anhydride, or a lower alkyl ester thereof, preferably at a reaction temperature using a commonly used condensation reaction catalyst. It is produced by carrying out esterification or transesterification reaction at 120 to 250 ° C. under normal pressure or reduced pressure.

The degree of crosslinking of the crosslinked polyethylene glycol compound of the present invention can be confirmed by the gel fraction when water is used as the solvent. Disperse in a sufficient amount of water (2000 times as a standard by weight ratio) with respect to the cross-linked polyethylene glycol compound, stir for 48 hours while maintaining the water temperature at 40 ° C, and filter to dry the solid content obtained. Then
If the ratio to the weight of the original polyethylene glycol compound is calculated as a percentage, the gel ratio as a measure of crosslinkability can be calculated. The crosslinked polyethylene glycol compound used for the purpose of the present invention preferably has a gel fraction of 50% or more. In particular, if the washable pressure-sensitive adhesive surface may be attached to the adherend and peeled off, in order to prevent the adhered surface from being contaminated with the washable pressure-sensitive adhesive, a cross-linked polyethylene having a gel fraction of 70% or more. It is preferable to use a glycol compound. These cross-linked polyethylene glycol compounds should not be water-soluble from the viewpoint of repeated tackiness by washing with water, and should be insoluble in water as indicated by the gel fraction.

When a crosslinked polyethylene glycol compound and a radiation curable resin are mixed as a washable pressure-sensitive adhesive,
The crosslinked polyethylene glycol compound is insoluble and swells in the radiation curable resin. The radiation-curable resin is incorporated into the network structure formed by the cross-linked molecular chains of the polyethylene glycol compound, and the form of the cross-linked polyethylene glycol compound before mixing swells in a similar shape reaching several tens to several thousand times in volume. Therefore, the viscosity of the washable pressure-sensitive adhesive is greatly affected by the particle size of the crosslinked polyethylene glycol compound, and the coating surface when applied to the support is largely influenced by the form of the crosslinked polyethylene glycol compound. If the glycol compound does not have a uniform shape, it becomes difficult to make the coated surface uniform, and it becomes difficult to control the adhesive strength.

The present invention is characterized by using a crosslinked polyethylene glycol compound finely pulverized to a particle size of 100 μm or less. Since it is finely pulverized as a powder with a particle size of 100 μm or less, the viscosity does not increase so much even if it swells after mixing with a radiation curable resin, and the uniformity of the coated surface is obtained from the uniformity of the particle size. And the adhesive force can be easily controlled. The particle size referred to in the present invention means JIS Z880.
When a standard screen defined by 1 and having a nominal size of 100 μm or less is used for screening according to JIS R5201, the size of particles that can pass through the screen is defined. As the standard sieve, either a mesh sieve or a plate sieve may be used.

The crosslinked polyethylene glycol compound is finely pulverized by using a commonly used pulverizer. Specifically, ball mill, impact fine crusher, jet crusher,
Tower mills, colloid mills, ring roll mills, stamp mills, rod mills, cone mills, roll crushers, screw intermediate crushers, edge runners, etc. are used, and if necessary, jaw crushers, joyrate crushers, hammer mills, etc. were used. A method of performing coarse pulverization and then fine pulverization may be used. Further, as a method for pulverizing, a dry method and a wet method can be mentioned. However, since the crosslinked polyethylene glycol compound of the present invention has a water absorbing property, the dry method is preferably used because the physical properties thereof hardly change during the pulverizing process. Further, a so-called freeze-grinding method may be used in which the crosslinked polyethylene glycol compound is frozen and crushed for crushing.

After the crosslinked polyethylene glycol compound finely pulverized to a particle size of 100 μm or less and the radiation curable resin are mixed and prepared, they may be dispersed using various dispersers before being applied to the support. The dispersion is carried out by simultaneously or individually introducing the crosslinked polyethylene glycol compound and the radiation curable resin into the disperser. Examples of the disperser used include a two-roll, three-roll, ball mill, sand grinder, disper, high-speed impeller disperser, and high-speed mixer homogenizer.

The washable pressure-sensitive adhesive of the present invention may contain a pigment. In the present invention, the pigment component improves the blocking resistance of the washable pressure-sensitive adhesive,
This is an effect that the dust adhering to the surface of the adhesive can be easily washed away by washing with water or the like.

The pigment contained in the washable pressure-sensitive adhesive of the present invention may be either an inorganic pigment or an organic pigment, specifically silica, kaolin, clay, calcium carbonate,
Aluminum hydroxide, titanium oxide, zinc oxide, glass particles, shirasu balloon, melamine resin particles, benzoguanamine resin particles, styrene resin particles, polymethylmethacrylate resin particles, polyolefin resin particles, starch particles and the like can be exemplified, but among them, silica, Glass particles and organic pigment-based resin particles are preferred. The blending ratio of the pigment can be used in the range of 0.5 to 100 parts by weight with respect to the total weight of the radiation curable resin constituting the washable pressure-sensitive adhesive and the polyethylene glycol compound having a crosslinked structure,
It can be preferably used in the range of 3 to 80 parts by weight. If the amount of the pigment component is less than this ratio, the blocking resistance cannot be sufficiently exhibited. On the other hand, if it exceeds this range, not only the adhesive strength and tackiness of the washable pressure-sensitive adhesive are reduced,
It is not preferable because the water resistance may be lowered or it may be difficult to apply it to the support.

The size of the pigment used in the present invention is preferably in the range of 1 to 20 μm in average particle diameter, and particles larger or smaller than this range may be present, but the average particle diameter of the pigment is If it is less than this range, the blocking resistance cannot be sufficiently expressed, and if it is more than this range, the adhesive strength or tackiness of the washable pressure-sensitive adhesive is reduced,
The surface strength may decrease and problems such as falling off from the coated support may occur.

In the washable pressure-sensitive adhesive of the present invention, a tackifier such as a petroleum resin, a terpene resin or a rosin resin can be mixed and used as long as the washability is not hindered.

Further, esters such as phthalic acid ester, phosphoric acid ester, adipic acid ester, sebacic acid ester, linoleic acid ester and the like used in general pressure-sensitive adhesives, paraffin, animal / vegetable oil, mineral oil, silicone oil, etc. A softening agent, an antioxidant, a filler, an ultraviolet absorber, a vulcanizing agent, a cross-linking agent, a stabilizer, a colorant and the like can be added and used.

The support used in the present invention is particularly restricted in materials such as paper, synthetic paper, wood surface, fiber, woven cloth, non-woven cloth, synthetic resin surface, synthetic resin laminated paper, release paper, metal surface and glass surface. Not a thing. The synthetic resin is not particularly limited, such as polyethylene, polypropylene, polyester, polyvinyl chloride, polyvinylidene chloride, polyurethane, polymethacrylate, polystyrene, polyamide, polyimide, polymethylpentene, foam synthetic resin, vinylon and nylon. The thickness also depends on the application and is not particularly limited. Corona treatment,
There is no problem in controlling the wettability of the support in the form of flame treatment, ozone treatment, anchor layer coating, or the like.

The adhesive product having the washable pressure-sensitive adhesive of the present invention is provided in the form provided, in a form in which the washable pressure-sensitive adhesive surface is exposed, or if necessary, release paper,
It may have a form in which the washable pressure-sensitive adhesive surface is covered with a release film or the like, or may have a form in which the pressure-sensitive adhesive is laminated in multiple layers such as an adhesive tape. Also in the manufacturing method, a method in which a washable pressure-sensitive adhesive is directly applied to and immobilized on a support, a washable pressure-sensitive adhesive is applied to a peelable support, and the peelable support is superposed on the support after irradiation with radiation. Any method such as a method of peeling the body and fixing it on the support, or a method of applying a washable pressure-sensitive adhesive to the peelable support, superimposing it on the support, polymerizing by irradiation with radiation, and fixing on the support The method may be used.

The washable pressure-sensitive adhesive of the present invention can be applied to the entire surface of the support or can be applied in a pattern to only a part of the support. The amount of the washable pressure-sensitive adhesive applied is preferably 1 to 50 g / m ² in terms of dry weight, from the viewpoint of tackiness. For the method of applying washable pressure-sensitive adhesive, gravure coater, comma coater,
Any coater such as a U comma coater, a multi-roll coater, an air knife coater, a blade coater, a curtain coater, a rod coater, a die coater, a micro gravure coater may be used.

In the present invention, in order to carry the washable pressure-sensitive adhesive on the support, polymerization and immobilization are carried out by irradiating with radiation after coating the support.

Among the radiations, as the electron beam accelerator used for electron beam irradiation, a curtain system, a scan system or a double scan system can be adopted, but a curtain system is preferable because it is relatively inexpensive and can easily obtain a large output. The acceleration voltage of the electron beam is 100 to 1000 kV, preferably 150 to
It is 300 kV, and the irradiation dose is 0.5 in absorbed dose.
~ 30 Mrad. If the accelerating voltage is less than 100 kV, the amount of energy transmitted is insufficient, and if it exceeds 1000 kV, the energy efficiency is reduced, which is not economical. On the other hand, if the irradiation dose is smaller than this range, the effect of residual monomers may appear, and problems such as washability and residual pressure-sensitive adhesive on the adherend may occur. On the other hand, if the irradiation dose is higher than this range, not only the energy efficiency may be lowered, but also the support may be deteriorated or the crosslinking may be excessively advanced to lower the tackiness.

In the radiation, when the washable pressure-sensitive adhesive is polymerized by irradiation with ultraviolet rays, a polymerization initiator may be added to the washable pressure-sensitive adhesive, if necessary. There are discharge lamp method, flash method, laser method, electrodeless lamp method, etc.
Further, as a generation source, there are a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, a pulse xenon lamp, an electrodeless discharge lamp, and the like, and the mercury discharge lamp is preferably used.

The polymerization initiator to be used in combination when polymerized by irradiation with ultraviolet rays (also called a photoinitiator) is
It is a substance that absorbs ultraviolet rays and is excited to generate radicals to start radical reaction.Unlike when using an electron beam, the radical reaction does not occur even if ultraviolet rays are irradiated using only a radiation curable resin. Does not happen and does not polymerize. As the polymerization initiator, chloroacetophenones, diethoxyacetophenones, hydroxyacetophenones, α-
In addition to acetophenone compounds such as aminoacetophenones, benzoin compounds such as benzoin ethers, benzophenone compounds, thioxanthone compounds, α-acyl oxime ester compounds, acylphosphine oxide compounds, glyoxy ester compounds, azo compounds, and benzyl dimethyl ketal , Methyl-O-benzoylbenzoate, 3-ketocoumarin, 2-ethylanthraquinone, camphorquinone, benzyl, Michler's ketone, tetramethylthiuram monosulfide, 3,3 ', 4,4'-tetra (t
There are compounds such as -butylperoxycarbonyl) benzophenone.

The polymerization initiator is selected from the viewpoints of compatibility with the radiation curable resin and the crosslinked polyethylene glycol compound, suitability with an ultraviolet irradiation device, and the like. The amount of the polymerization initiator used is usually 0.
It is used in the range of 1 to 5 parts by weight. If the amount of the polymerization initiator used is less than the above range, the radiation-curable resin may undergo a curing reaction by irradiation with ultraviolet rays, but the curing rate is slow, and unreacted substances may remain after the step is completed. Not preferable. On the other hand, if the amount used is larger than the above range, not only the cost will increase because it does not participate in the curing reaction of the radiation curable resin, but also the proportion of impurities contained in the resin composition increases, which is not preferable.

The washable pressure-sensitive adhesive of the present invention may further contain a polymerization initiation auxiliary agent in addition to the polymerization initiator in order to accelerate the reaction by ultraviolet irradiation. The polymerization initiation aid does not generate radicals when it is exposed to ultraviolet rays, but when used in combination with a polymerization initiator, it accelerates the reaction and makes the curing reaction of the UV curable resin efficient. Is a substance having Examples of the polymerization initiation aid include compounds such as aliphatic or aromatic amines, sulfones, and phosphines.

Since the polymerization-crosslinking reaction by irradiation proceeds by a radical reaction, depending on the oxygen concentration in the atmosphere, substitution with an inert gas such as nitrogen, helium, carbon dioxide, etc. is carried out, and the oxygen concentration is 600 ppm or less, preferably. Is preferably irradiated in an atmosphere of 400 ppm or less.

The tackiness of the washable pressure-sensitive adhesive of the present invention can be controlled by the composition of the washable pressure-sensitive adhesive, the coating amount, the degree of radiation irradiation, the additive, the moisture content, etc. If necessary, it can be used in the range of 5 to 3000 gf / 25 mm (180 degree peeling, 300 mm / min peeling speed). If the adhesive strength is less than this range, it will be too lightly peeled even as a sticky note used for the lightest adhesive, and even if the adhesive strength is larger than this range, not only a large amount of energy is required for peeling, but also deterioration and destruction of the support during peeling. May occur.

The ratio of the radiation-curable resin which is the main component of the washable pressure-sensitive adhesive of the present invention to the cross-linked polyethylene glycol compound is 100% by weight of the radiation-curable resin.
0.5 to 0.5 parts of the polyethylene glycol compound
It is a ratio of 100 parts by weight. If the proportion of cross-linked polyethylene glycol compound is less than this range, sufficient adhesive strength,
Washability does not easily appear, and if it exceeds this range, the viscosity sharply increases and the coatability deteriorates.

The washable pressure-sensitive adhesive of the present invention is characterized in that it can be applied and fixed without a solvent. However, it can be applied after diluting it with water or an organic solvent, if necessary. Further, it does not matter to dry after coating.

As described above, the washable pressure-sensitive adhesive polymerized by irradiation of radiation exhibits an adhesive performance that is acceptable for use as a washable pressure-sensitive adhesive as it is, but is left to stand for a long time. If so, the adhesive performance may be deteriorated and sufficient adhesive force may not be exhibited. This deterioration over time is due to the fact that unreacted radical species trapped in the resin composition polymerized by irradiation further promotes the polymerization of the radiation curable resin which is the composition of the washable pressure-sensitive adhesive. Is the cause. In the present invention, it has been found that treatment of a pressure-sensitive washable pressure-sensitive adhesive polymerized by irradiation with a radical polymerization inhibitor can significantly improve the deterioration of the adhesive performance over time. By performing the radical polymerization inhibitor treatment, the unreacted radical species trapped in the resin composition can be inactivated. Such radical polymerization inhibitors include dichlorobenzoquinones, trinitrobenzenes, nitrosobenzenes, butylcatechols, picric acids, nitrobenzoic acids, oxygen and active oxygen, cupric chloride, ferric chloride, halogenated compounds. Generally known radical polymerization inhibitors such as cobalt, diphenylpicrylhydrazyl, tetraethylphenylenediamine, chloranil and iodine can be used.
These radical polymerization inhibitors can be used alone or as a solution, and after the treatment, they can be washed with water or a solvent. There may be a method in which a radical polymerization inhibitor is mixed with a resin composition comprising a radiation curable resin and a polyethylene glycol compound having a crosslinked structure from the beginning at a concentration equal to or higher than the concentration of the polymerization inhibitor for resin storage. Considering the inhibition and the decomposition of the polymerization inhibitor upon irradiation with radiation, it is more effective to treat with the radical polymerization inhibitor again after irradiation with radiation.

The radical polymerization inhibitor may be applied by, for example, blade coating, air doctor coating,
Methods such as squeeze coating, air knife coating, reverse roll coating, gravure roll and transfer roll coating, bar coating, curtain coating, kiss coating, gate roll coating, and tab size are used. In addition, there is no problem in drying after coating.

The tacky product using the washable pressure-sensitive adhesive of the present invention not only exhibits sufficient tackiness but also loses its tackiness instantly by washing with water or an organic solvent after use. Washable Pressure-sensitive adhesive Dust adhered to the surface can be washed away. When used for an adhesive label, the label can be instantly peeled off from the adherend by placing it in water. When peeled off, the washable pressure-sensitive adhesive has an excellent function of not remaining on the adherend at all.

The tacky product using the washable pressure-sensitive adhesive of the present invention instantly loses its tackiness due to water or an organic solvent, but after the water or the organic solvent evaporates, the tackiness is exhibited again. Therefore, for example, a dust removing roll,
When used for dust mats and sole mats, after being used for a certain period of time, after the pressure-sensitive adhesive surface has been contaminated with dust, dirt, or dust, these contaminants are removed by simple washing with water and then dried. If so, the tackiness is easily restored, and it can be used repeatedly. The washable pressure-sensitive adhesive does not flow out by simple water washing, and it is possible to obtain almost the same tackiness as before.

[0049]

The washable pressure-sensitive adhesive of the present invention is coated without solvent,
It can be fixed at low temperature by irradiation with radiation, and can exhibit an appropriate adhesive force. As an adhesive product, it exhibits sufficient adhesiveness, and can lose its adhesive force instantly with water or an organic solvent to wash the adhesive surface. After evaporation of water or the organic solvent, the adhesive property is developed again, and the product can be repeatedly used as an adhesive product. The washable pressure-sensitive adhesive layer has a high coating strength, and the washable pressure-sensitive adhesive does not remain on the adherend even when the washable pressure-sensitive adhesive is peeled off from the adherend. The function of the radical polymerization inhibitor can inactivate unreacted radical species after irradiation, and can suppress the excessive progress of polymerization, so that the adhesive performance is excellent over time and the adhesive strength even after being left for a long time. No deterioration is observed, and sufficient tackiness is exhibited.

[0050]

The present invention will be described in detail below with reference to examples, but the contents of the present invention are not limited to the examples.
Unless otherwise specified, parts and% are parts by weight and% by weight, respectively.

Example 1 Molecular weight of 20,000 as polyethylene glycol compound
Of 10000 parts of ethylene oxide was added to 2000 parts of polypropylene glycol, and a transesterification reaction was performed with 194 parts of dimethyl terephthalic acid to obtain a polyethylene glycol compound, which was dried and then subjected to γ-ray irradiation with cobalt 60 to obtain the target crosslinked polyethylene. A glycol compound was obtained. To 100 parts of the obtained cross-linked polyethylene glycol compound, 50 parts of acrylic acid dimer and 50 parts of N-vinylformamide as a radiation curable resin were well mixed to obtain a desired washable pressure-sensitive adhesive. As the support, a laminated paper having a thickness of 100 μm and a polyethylene laminate layer of 20 μm provided on a high-quality paper is used, and after corona treatment, a coating amount of 50 g / m ² is applied, and a 3 Mrad electron beam is applied by an electron beam irradiation device. Irradiation was carried out in a nitrogen atmosphere to obtain an adhesive product.

Example 2 The adhesive product obtained in Example 1 was further coated with a toluene solution of 3% diphenylpicrylhydrazyl and dried to obtain an adhesive product treated with a radical polymerization inhibitor. Obtained.

Example 3 Crosslinked polyethylene glycol compound 10 obtained in Example 1
To 0 parts, 50 parts of acrylic acid dimer and 50 parts of N-vinylformamide as a radiation curable resin, and 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1 as a polymerization initiator Four parts were sequentially mixed, and well dispersed using a high-speed homogenizer to obtain an intended washable pressure-sensitive adhesive. The support used was the same as the laminated paper used in Example 1, and after corona treatment, it was coated at a coating amount of 50 g / m ² and 120 W /
Ultraviolet irradiation was performed in a nitrogen atmosphere by using 4 cm high-pressure mercury ultraviolet irradiation lamps to obtain an adhesive product.

Example 4 The sticky product obtained in Example 3 was further added with 5% tri-P-
After application of an alcohol solution of nitrophenyl and drying, an adhesive product treated with a radical polymerization inhibitor was obtained.

Example 5 Molecular weight of 20,000 as polyethylene glycol compound
Using 20,000 parts of polyethylene glycol of No. 2 above, an esterification reaction was performed with 166 parts of phthalic acid to obtain a polyethylene glycol compound, which was dried and then irradiated with electron beam to obtain a crosslinked polyethylene glycol compound. The obtained crosslinked polyethylene glycol compound was pulverized by a freeze pulverization method, and those having a sieve size of 125, 100, 88 μm, respectively, were made into a crosslinked polyethylene glycol compound powder having a particle size of 125, 100, 88 μm, and The cross-linked polyethylene glycol compound powder and polypropylene glycol diacrylate as a radiation curable resin were thoroughly mixed to obtain the intended washable pressure-sensitive adhesive. The weight ratio of the cross-linked polyethylene glycol compound and the radiation curable resin is 0.3 / 100, 0.5 / 100, 1/100,
There are 6 types, 5/100, 10/100, and 20/100. Corona treatment is applied to 100 μm-thick coated paper as a support, and each washable pressure-sensitive adhesive subjected to dispersion treatment with a high-speed homogenizer is applied with a comma coater at an application amount of 15 g / m ² and then with an electron beam irradiation device. Irradiation with an electron beam of 0.5 Mrad was performed in a nitrogen atmosphere to obtain a target adhesive product.

Example 6 Molecular weight of 10,000 as polyethylene glycol compound
10000 parts of polyethylene glycol was used to perform an esterification reaction with 98 parts of maleic anhydride to obtain a polyethylene glycol compound, which was dried and then irradiated with an electron beam to obtain a crosslinked polyethylene glycol compound. The obtained cross-linked polyethylene glycol compound was pulverized by a freeze pulverization method, and those having a sieve size of 105, 100, and 62 μm, respectively, were passed through a sieve having a particle size of 105, 10 respectively.
A crosslinked polyethylene glycol compound powder having a particle size of 0.62 μm was prepared, and each crosslinked polyethylene glycol compound powder and hydroxy-3-phenoxy acrylate as a radiation curable resin were well mixed to obtain the intended washable pressure-sensitive adhesive. The weight ratios of the crosslinked polyethylene glycol compound and the radiation curable resin are 5/100 and 20 /, respectively.
100, 50/100, 80/100, 100/10
There are 6 types, 0 and 120/100. A 100 μm thick transparent polyester sheet as a support was corona-treated, and each washable pressure-sensitive adhesive that had been dispersed by a high-speed homogenizer was coated with a comma coater at a coating amount of 25 g / m ² , and an electron beam irradiation device was used. Was irradiated with an electron beam of 1 Mrad in a nitrogen atmosphere to obtain the target adhesive product.

Example 7 10000 parts of polyethylene glycol having a molecular weight of 2000 was used as a polyethylene glycol compound, an esterification reaction was carried out with 98 parts of trimellitic acid, and dried to obtain a crosslinked polyethylene glycol compound. The obtained crosslinked polyethylene glycol compound was pulverized by the freeze pulverization method, and the one having a sieve of 44 μm was able to pass through the sieve.
Crosslinked polyethylene glycol compound powder having a particle size of 44 μm was prepared, and hydroxy-3-phenoxy acrylate was well mixed as a radiation curable resin to obtain the intended washable pressure-sensitive adhesive. The weight ratio of the crosslinked polyethylene glycol compound and the radiation curable resin is 10/100. Acrylonitrile fiber as a support (manufactured by Unitika Ltd., 3d x
3 mm) was applied by a wet papermaking process using a non-woven sheet having a basis weight of 120 g / m ² at a coating amount of 25 g / m ² , and electron beam irradiation of 1 Mrad was performed in a nitrogen atmosphere by an electron beam irradiation device to obtain the target adhesion. Got the product.

Example 8 The adhesive product obtained in Example 7 was further coated with a 3% alcohol solution of p-benzoquinone and then dried to obtain an adhesive product treated with a radical polymerization inhibitor. .

Example 9 Molecular weight of 20,000 as polyethylene glycol compound
10000 parts of polyethylene glycol was used to react with 98 parts of diphenylmethane diisocyanate to give a polyethylene glycol compound. After drying, electron beam irradiation was carried out to obtain a crosslinked polyethylene glycol compound. The obtained crosslinked polyethylene glycol compound was pulverized by a freeze pulverization method, and a powder having a sieve size of 62 μm was passed through to obtain a crosslinked polyethylene glycol compound powder having a particle size of 62 μm, which was used as a radiation curable resin and hydroxy-3-phenoxypropyl acrylate. Was thoroughly mixed to obtain the intended washable pressure-sensitive adhesive. The weight ratio of the crosslinked polyethylene glycol compound and the radiation curable resin is 10/10.
It is 0. Furthermore, after mixing 10 parts of synthetic silica (Mizukasil P832, manufactured by Mizusawa Chemical Industry Co., Ltd., average particle size 3 μm) as a pigment with 100 parts of this washable pressure-sensitive adhesive, polyvinyl chloride having a thickness of 1 mm was used as a support. Using, a washable pressure-sensitive adhesive that has been well-dispersed using a high-speed homogenizer is applied at a coating amount of 20 g / m ² , and electron beam irradiation of 1 Mrad is performed in a nitrogen atmosphere by an electron beam irradiation device. The desired sticky product was obtained.

Example 10 The adhesive product obtained in Example 9 was further supplemented with 2% of copper chloride (I
I) The solution was applied and then dried to obtain an adhesive product treated with a radical polymerization inhibitor.

Example 11 Hydroxyl-3-phenoxyacrylate as a radiation curable resin and methylphenylglyoxylate as a polymerization initiator were added to the crosslinked polyethylene glycol compound powder having a particle size of 100 μm obtained in Example 6. Each of them was mixed well at a weight ratio of 10/100/5 to obtain the intended washable pressure-sensitive adhesive. Then, using an aluminum foil laminated paper as a support, a coating amount of 15 g / m ² is applied and 120 W
UV irradiation was performed in a nitrogen atmosphere using 6 high-pressure mercury ultraviolet irradiation lamps of / cm to obtain the target adhesive product.

Example 12 The adhesive product obtained in Example 11 was further added with 5% p-te.
An adhesive solution treated with a radical polymerization inhibitor was obtained by applying an alcohol solution of rt-butylcatechol and then drying it.

Example 13 To 100 parts of the same washable pressure-sensitive adhesive as in Example 1, 0.5 parts of glass particles having an average particle size of 5 μm were mixed and kneaded well, and then the support had a thickness of 1 mm. Polyvinyl chloride was used for coating at a coating amount of 30 g / m ² , and electron beam irradiation with an electron beam irradiation device of 5 Mrad was performed in a nitrogen atmosphere to obtain the target adhesive product.

Example 14 The adhesive product obtained in Example 13 was further supplemented with 2% N, N,
An alcohol solution of N ', N'-tetraethyl-p-phenylenediamine was applied and then dried to obtain an adhesive product treated with a radical polymerization inhibitor.

Example 15 Crosslinked polyethylene glycol compound 10 obtained in Example 1
To 0 parts, acrylic acid dimer 5 as a radiation curable resin
0 part and 50 parts of N-vinylformamide, and 2-methyl-1- [4- (methylthio) as a polymerization initiator
4 parts of phenyl] -2-morpholinopropane-1 were sequentially mixed to obtain the desired washable pressure-sensitive adhesive.
Then, using polyvinyl chloride having a thickness of 1 mm as a support, and coating at a coating amount of 30 g / m ² , 120 W / cm
6 high-pressure mercury UV irradiation lamps were used to perform UV irradiation in a nitrogen atmosphere to obtain the target adhesive product.

Comparative Example 1 Radiation curable resin used in Example 1 (mixture of 50 parts of acrylic acid dimer and 50 parts of N-vinylformamide)
Only the same was coated on a support similar to that in Example 1, and the same electron beam irradiation as in Example 1 was performed to obtain a sample of Comparative Example 1.

Comparative Example 2 The sample obtained in Comparative Example 1 was coated with a toluene solution of 3% diphenylpicrylhydrazyl and then dried to treat with a radical polymerization inhibitor. I got a sample.

Comparative Example 3 Radiation curable resin used in Example 3 (mixture of 50 parts of acrylic acid dimer and 50 parts of N-vinylformamide).
And a polymerization initiator (4 parts of 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1)
Was coated on a support similar to that in Example 3, and the same ultraviolet irradiation as in Example 3 was performed to obtain a sample of Comparative Example 3.

Comparative Example 4 The adhesive product obtained in Comparative Example 3 was further supplemented with 5% tri-P-
A sample of Comparative Example 4 which was treated with a radical polymerization inhibitor was obtained by applying an alcohol solution of nitrophenyl and then drying it.

Comparative Example 5 The radiation curable resin used in Example 7 was applied to the same support as in Example 7, and the same electron beam irradiation as in Example 7 was performed to obtain a sample of Comparative Example 5.

Comparative Example 6 The sample obtained in Comparative Example 5 was coated with a 3% alcohol solution of p-benzoquinone and then dried to obtain a sample of Comparative Example 6 which was treated with a radical polymerization inhibitor. Obtained.

Comparative Example 7 A support similar to that of Example 6 was coated with the following pressure-sensitive adhesive 25
It was applied to a thickness of μm. As the pressure-sensitive adhesive, a resin composition in which an equimolar copolymer of maleic anhydride / vinyl methyl ether and methoxytriethylene glycol monoacrylate were uniformly mixed at a weight ratio of 6: 4 was used.
After coating, electron beam irradiation of 3 Mrad was performed in a nitrogen atmosphere to obtain a sample of Comparative Example 7.

Comparative Example 8 The sample of Comparative Example 7 was further coated with a 3% methyl ether hydroquinone alcohol solution and then dried to be treated with a radical polymerization inhibitor.
I got a sample of.

Comparative Example 9 A sample of Comparative Example 9 was obtained in the same manner as Comparative Example 7 except that the electron beam irradiation amount was 10 Mrad.

Comparative Example 10 Polyethylene glycol 2000 (Wako Pure Chemical Industries, average molecular weight 200 as a non-crosslinked polyethylene glycol compound)
0, gel fraction 0%) and hydroxy-3-phenoxy acrylate as a radiation curable resin were mixed well to obtain a washable pressure-sensitive adhesive. The weight ratio of the polyethylene glycol compound and the radiation curable resin is 10/100. Corona treatment is applied to a transparent polyester sheet with a thickness of 100 μm as a support, and a pressure sensitive adhesive is applied with a comma coater at an application amount of 25 g / m ² and then 3 Mr is applied by an electron beam irradiation device.
A sample of Comparative Example 10 was obtained by performing electron beam irradiation of ad.

Comparative Example 11 A sample of Comparative Example 11 was obtained by further applying a 3% alcohol solution of p-benzoquinone to the sample of Comparative Example 10 and then drying it to treat it with a radical polymerization inhibitor.

Comparative Example 12 The same solvent-type pressure-sensitive adhesive as described in Example 6 was coated with the following solvent-type pressure-sensitive adhesive at a thickness of 20 g / m ² . As a pressure sensitive adhesive, an acrylic pressure sensitive adhesive (manufactured by Toyo Ink, BPS481
9), polyfunctional polyisocyanate (manufactured by Nippon Polyurethane, Coronate L), superabsorbent sodium polyacrylate (manufactured by Nippon Shokubai, Aqualic CA ML-20),
Weight ratio of toluene and ethyl acetate is 100/1/2/10
The resin composition mixed at / 10 was used. And dried in hot air at 95 ° C. for 2 minutes to obtain a sample of Comparative Example 12.

The following evaluation tests were conducted on the samples obtained in Examples 1 to 15 and Comparative Examples 1 to 12. The results are shown in Tables 1-5. In the table, the weight ratio of the polyethylene glycol compound to the radiation curable resin is expressed as the PEG / RC ratio.

(Test 1 ... Adhesive strength) The adhesive surface of the sample was coated with a polyester film (O-100 made by Diamond Foil).
No.), leave it under a constant load for 24 hours, and
It was cut into a width of mm and peeled at 180 ° at a speed of 300 mm / min by a Tensilon universal tensile tester to measure the adhesive strength.

(Test 2 ... Water releasability) The adhesive surface of the sample was adhered to a polyester non-woven fabric, and the sample was placed under a constant load for 24 hours.
Allow to stand for a while, cut into 25 mm width, throw in water and stir,
The time taken for the polyester nonwoven fabric to peel from the adhesive surface was measured. It should be noted that no measurement was performed when peeling did not occur even after 100 seconds had elapsed (indicated as> 100 in the table).

(Test 3 ... Re-adhesiveness) The sample was put into water, washed with water for 10 minutes, dried, and attached to a polyester film under the same conditions as those used in the adhesive strength test.
After being left under the same load for 24 hours, 180 ° peeling was performed with a Tensilon universal tensile tester at a speed of 300 mm / min to measure the readhesion force. As an evaluation result, in the table,
The ratio (%) of the re-adhesive strength to the adhesive strength before water washing (adhesive strength of Test 1) is shown.

(Test 4 ... Adhesion with time 1) The adhesive surface of the sample was left for 2 weeks to leave it as a sample with a time of -1, and the same test as the adhesion test was conducted to measure the adhesion. In the table as the evaluation result, the adhesive strength before washing (Test 1
The ratio (%) of the adhesive strength over time -1 to the adhesive strength of 1) is shown.

(Test 5 ... Adhesiveness with time 2) After leaving the adhesive surface of the sample exposed to sunlight for 1 month, the sample was immersed in running water for 3 minutes to wash away the dust adhering to the adhesive surface. Then, the sample was dried and used as a sample for aging −2, and the same test as the adhesive strength test was performed to measure the adhesive strength. In the table as the evaluation result, the adhesive strength before washing (Test 1
The ratio (%) of the adhesive strength over time-2 with respect to the (adhesive strength of) was shown.

[0084]

[Table 1]

[0085]

[Table 2]

[0086]

[Table 3]

[0087]

[Table 4]

[0088]

[Table 5]

Evaluation: The adhesive product samples prepared in the examples can be applied without solvent or solvent, and are hard to be exposed to radiation, so that the dry heat zone is insoluble and the adhesive product has sufficient adhesiveness. can get. Further, when the crosslinked polyethylene glycol compound is pulverized and used as a powder having a particle size of 100 μm or less, the adhesive force can be easily controlled. Also, the adhesive strength can be easily controlled by changing the mixing ratio of the radiation curable resin and the crosslinked polyethylene glycol compound. These samples not only have adhesiveness, but lose their adhesiveness by washing with water, and the adherend adhered to the surface of the washable pressure-sensitive adhesive can be peeled off and washed off. When the water evaporates, the adhesive strength is almost restored to that before washing with water. In addition, since the washable pressure-sensitive adhesive does not contain water or solvent and cross-linking or polymerization of the washable pressure-sensitive adhesive once polymerized by irradiation is difficult to proceed further, the washable pressure-sensitive adhesive is exposed to the outside air. It is possible to obtain a washable pressure-sensitive adhesive product having good properties, which can maintain the adhesive strength for a long period of time even when exposed to the sun or exposed to the sunlight. Further, when the treatment with the radical polymerization inhibitor is carried out, long-term storability can be obtained with almost no decrease in adhesive strength. Furthermore, a washable pressure-sensitive adhesive product having these good properties can be obtained regardless of the substrate.

On the other hand, as shown in the comparative example, the radiation curable resin alone cannot provide the above characteristics. It is also clear that the polyethylene glycol compound used cannot be used for the purpose of the present invention even if it is not crosslinked. In addition, there are pressure-sensitive adhesives that lose their tackiness by washing with water, but even if they are dried, they only show a tackiness far below the original tackiness, or if they do not contain solvent or unreacted radical species in the pressure-sensitive adhesive. However, when it is exposed to the outside air, it loses its tackiness and does not become a washable pressure-sensitive adhesive.

[0091]

Industrial Applicability As described above, the present invention can be applied without solvent and without solvent, does not require a dry heat zone for curing upon irradiation with radiation, and has sufficient tackiness. To be In addition, the washable pressure-sensitive adhesive of the present invention can be washed with water, and the adherend adhered to the surface of the washable pressure-sensitive adhesive is peeled off, washed off, and then dried to recover the adhesive force and repeatedly adhered products. Can be used as It is possible to obtain a washable pressure-sensitive adhesive product having good adhesive stability over time even when the washable pressure-sensitive adhesive is exposed to the outside air or exposed to sunlight.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI technical display location C09J 7/02 JKZ 171/02 JFW (31) Priority claim number Japanese Patent Application No. 5-328087 (32) Priority Day 5 (1993) December 24 (33) Priority claiming country Japan (JP)

Claims (10)

[Claims] 1. A washable product characterized by comprising (1) a radiation curable resin and (2) a polyethylene glycol compound having a crosslinked structure, and having as a main component a polymer obtained by reaction by irradiation with radiation. Pressure sensitive adhesive. 2. A polyethylene glycol compound having a crosslinked structure is one or more selected from the group consisting of polyethylene glycol, polyvalent carboxylic acid, polyvalent carboxylic acid anhydride, polyvalent carboxylic acid lower alkyl ester, and polyvalent isocyanate. The washable pressure-sensitive adhesive according to claim 1, which is a polyethylene glycol compound obtained by reacting with a compound. 3. The washable pressure-sensitive adhesive according to claim 1 or 2, wherein the polyethylene glycol compound having a crosslinked structure is finely pulverized to have a particle size of 100 μm or less. 4. A washable pressure-sensitive adhesive, wherein the weight ratio of the radiation curable resin to the polyethylene glycol compound having a crosslinked structure is 100% by weight of the radiation curable resin, and the polyethylene glycol compound is 0.
The washable pressure-sensitive adhesive according to any one of claims 1 to 3, wherein the proportion is 5 to 100 parts by weight. 5. The washable pressure-sensitive adhesive has an average particle diameter of 1 to 2 with respect to a total amount of 100 parts by weight of a radiation curable resin and a polyethylene glycol compound having a crosslinked structure.
The washable pressure-sensitive adhesive according to claim 4, which contains 0.5 to 100 parts by weight of an organic or inorganic pigment having a thickness of 0 μm. 6. The washable pressure-sensitive adhesive according to any one of claims 1 to 5, wherein a resin composition comprising a radiation curable resin and a polyethylene glycol compound having a crosslinked structure is polymerized by irradiation with radiation, and then the resin. The composition is treated with a radical polymerization inhibitor.
5. A washable pressure-sensitive adhesive according to any one of 5 to 5. 7. The washable pressure-sensitive adhesive according to claim 1, wherein the radiation is an electron beam or an ultraviolet ray. 8. An adhesive product having a pressure-sensitive adhesive layer on at least one surface of a support, wherein the pressure-sensitive adhesive layer comprises (1)
A pressure-sensitive adhesive composition comprising 100 parts by weight of a radiation-curable resin and (2) 0.5 to 100 parts by weight of a polyethylene glycol compound having a crosslinked structure as a main component, which is cured by irradiation with radiation. And adhesive products. 9. An adhesive product having a pressure-sensitive adhesive layer on at least one surface of a support, wherein the pressure-sensitive adhesive layer comprises (1)
A pressure-sensitive adhesive composition containing 100 parts by weight of a radiation-curable resin and (2) 0.5 to 100 parts by weight of a polyethylene glycol compound having a crosslinked structure as main components is polymerized by irradiation with radiation, and then the pressure-sensitive adhesive composition is polymerized. An adhesive product, wherein the adhesive composition is treated with a radical polymerization inhibitor. 10. The adhesive product according to claim 7, wherein the radiation is an electron beam or an ultraviolet ray.