JP2018168333A - Adhesive product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a re-peelable adhesive body applied to a packaging material for storing a wet sheet impregnated with a liquid, which is less likely to cause adhesive residue when peeled from an adherend due to deterioration over time. An adhesive film 10 is applied to a packaging material for storing a wet sheet impregnated with a liquid, and includes a base material 1, an adhesive, and an ultraviolet absorber having a function of absorbing ultraviolet rays. It is provided with a peelable pressure-sensitive adhesive layer 2. The ultraviolet absorber preferably contains a compound having a conjugated unsaturated bond. The pressure-sensitive adhesive layer 2 preferably contains, in addition to the pressure-sensitive adhesive and the ultraviolet absorber, an oil-absorbing material having a function of absorbing oil. [Selection diagram] Fig. 1

Description

  The present invention relates to an adhesive body.

  A pressure-sensitive adhesive film having a re-peelable pressure-sensitive adhesive layer (re-peelable pressure-sensitive adhesive film) is easy to handle, and is used for various labels, lids, and the like (for example, see Patent Document 1).

However, the conventional re-peelable pressure-sensitive adhesive film has a problem that the pressure-sensitive adhesive deteriorates due to ultraviolet rays, and adhesive residue is generated when the re-peelable pressure-sensitive adhesive film is peeled from the adherend.
In particular, in a re-peelable pressure-sensitive adhesive applied as a lid for packaging material containing a wet sheet impregnated with liquid, when the lid label is turned outdoors, the pressure-sensitive adhesive layer is irradiated with ultraviolet rays. The occurrence of serious problems was remarkable.

JP 2014-224263 A

  An object of the present invention is to provide a re-peelable pressure-sensitive adhesive body which is applied to a packaging material containing a wet sheet impregnated with a liquid, which hardly causes adhesive residue when peeled from an adherend due to deterioration over time. It is in.

  Such an object is achieved by the present invention described in the following (1) to (9).

(1) A pressure-sensitive adhesive applied to a packaging material for storing a wet sheet impregnated with a liquid,
A substrate;
A pressure-sensitive adhesive body comprising: a pressure-sensitive adhesive and a re-peelable pressure-sensitive adhesive layer containing an ultraviolet absorber having a function of absorbing ultraviolet rays.

  (2) The pressure-sensitive adhesive body according to (1), wherein the ultraviolet absorber includes a compound having a conjugated unsaturated bond.

  (3) The pressure-sensitive adhesive according to (1) or (2), wherein the content of the ultraviolet absorber with respect to 100 parts by weight of the pressure-sensitive adhesive is from 0.1 parts by weight to 10 parts by weight.

  (4) The pressure-sensitive adhesive body according to any one of (1) to (3), which further includes an oil absorbent having a function of absorbing oil in addition to the pressure-sensitive adhesive and the ultraviolet absorber.

  (5) The pressure-sensitive adhesive body according to (4), wherein the oil absorbent is a polymer compound having a plurality of alicyclic structures in a repeating unit.

（ただし、式（１）中、ｎは２以上の整数、ｍは１以上４以下の整数を示す。） (6) The pressure-sensitive adhesive body according to (5), wherein the oil absorbing material has a chemical structure represented by the following formula (1).

(In the formula (1), n represents an integer of 2 or more, and m represents an integer of 1 to 4)

  (7) The pressure-sensitive adhesive body according to any one of (4) to (6), wherein a content ratio of the oil absorbent to 100 parts by mass of the pressure-sensitive adhesive is 0.1 part by mass or more and 50 parts by mass or less.

  (8) The pressure-sensitive adhesive according to any one of (1) to (7), wherein the pressure-sensitive adhesive contains a monomer having a saturated aliphatic hydrocarbon group having 5 or more carbon atoms as a constituent component.

  (9) The pressure-sensitive adhesive according to any one of (1) to (8), further comprising a plasticizer having an alkylene group having 4 or more carbon atoms in the molecule.

  ADVANTAGE OF THE INVENTION According to this invention, the re-peeling type adhesive body which cannot produce the adhesive residue at the time of peeling from the to-be-adhered body by deterioration over time can be provided.

It is a typical longitudinal section showing a 1st embodiment of an adhesion object (adhesion film) of the present invention. It is a typical longitudinal cross-sectional view which shows 1st Embodiment of the manufacturing method of the adhesive body (adhesive film) of this invention. It is a perspective view which shows suitable embodiment of a package (wrapping material). It is a cross-sectional side view in the state which closed the cover body of the package (wrapping material) shown in FIG. It is a cross-sectional side view in the state which opened the cover body of the package (wrapping material) shown in FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail.
In the present invention, the “re-peeling type” refers to a material that can be repeatedly stuck to and peeled from an adherend.

[Summary of the Invention]
By the way, in the conventional re-peelable pressure-sensitive adhesive film (pressure-sensitive adhesive body), the pressure-sensitive adhesive deteriorates with time, and there is a problem that adhesive residue is generated when the pressure-sensitive adhesive film is peeled off from the adherend. In particular, the occurrence of such a problem is remarkable in a re-peelable pressure-sensitive adhesive applied to a packaging material that stores a wet sheet impregnated with a liquid. The present inventor has conducted intensive research for the purpose of solving such problems. As a result, the inventors have found that ultraviolet rays greatly affect the deterioration of the pressure-sensitive adhesive, and have reached the present invention.

  That is, the pressure-sensitive adhesive body of the present invention is applied to a packaging material for storing a wet sheet impregnated with a liquid, and includes a base material, a pressure-sensitive adhesive, and a re-peeling material including an ultraviolet absorbent having a function of absorbing ultraviolet light. A pressure-sensitive adhesive layer of the mold.

  As described above, the pressure-sensitive adhesive layer contains the ultraviolet absorber, so that deterioration of the pressure-sensitive adhesive due to ultraviolet rays (particularly, light in the ultraviolet region included in external light such as sunlight) can be effectively prevented. It is possible to effectively prevent the problem of adhesive residue when peeling a body (for example, an adhesive film or the like) from an adherend. In particular, in the re-peelable pressure-sensitive adhesive body, when the pressure-sensitive adhesive body is peeled off from the adherend, the pressure-sensitive adhesive layer is directly exposed to external light, so that the pressure-sensitive adhesive deterioration easily proceeds due to ultraviolet rays. In contrast, in the present invention, even in such a re-peelable pressure-sensitive adhesive body, deterioration of the pressure-sensitive adhesive due to ultraviolet rays can be sufficiently prevented, and the pressure-sensitive adhesive body (for example, a pressure-sensitive adhesive film) is peeled off from the adherend. It is possible to effectively prevent the problem of adhesive residue during the process.

  In particular, the pressure-sensitive adhesive body of the present invention is applied to a packaging material that houses a wet sheet impregnated with a liquid. In such a packaging material, a plurality of wet sheets are usually stored, and the adhesive layer is irradiated with ultraviolet rays each time the wet sheet as a stored item is taken out. Such a packaging material may be used outdoors where the intensity of ultraviolet rays is high. Therefore, among the various pressure-sensitive adhesive bodies, the above-described problem is particularly likely to occur. However, according to the present invention, the occurrence of the above-described problem can be effectively prevented.

[Re-peelable pressure-sensitive adhesive composition]
First, the re-peelable pressure-sensitive adhesive composition that can be suitably used for producing the pressure-sensitive adhesive body of the present invention will be described.

  The re-peelable pressure-sensitive adhesive composition of the present embodiment used for the production of the pressure-sensitive adhesive body of the present invention includes a pressure-sensitive adhesive and an ultraviolet absorber having a function of absorbing ultraviolet rays.

<Adhesive>
Examples of the pressure-sensitive adhesive contained in the re-peelable pressure-sensitive adhesive composition include acrylic, synthetic rubber and natural rubber, and acrylic pressure-sensitive adhesive is preferred.
Thereby, the adhesiveness with respect to a to-be-adhered body can be made more excellent.

  The acrylic pressure-sensitive adhesive is acrylic acid, methacrylic acid (hereinafter collectively referred to as “(meth) acrylic acid”) or ester compounds thereof (acrylate, methacrylate (hereinafter collectively referred to as “meth (acrylate)”). ) ”), And the like as long as they contain a (meth) acrylic acid derivative as a monomer component, and may be a copolymer. Moreover, you may contain monomer components other than the above.

  The pressure-sensitive adhesive preferably contains a monomer having a saturated aliphatic hydrocarbon group having 5 or more carbon atoms as a constituent component.

  Thereby, it is possible to make the adhesive itself have excellent resistance to ultraviolet rays, and it is possible to more effectively prevent the deterioration of the adhesive and the problem of adhesive residue as described above.

  Moreover, the lipophilicity as the whole re-peelable pressure-sensitive adhesive composition (the whole pressure-sensitive adhesive layer) can be made more excellent. As a result, when the re-peelable pressure-sensitive adhesive composition contains an oil absorbing material that will be described in detail later, the absorbed oil is more suitably retained inside, combined with the effect of including the oil absorbing material (the effect that will be described in detail later). It is possible to improve the adhesive strength retention effect when in contact with oil. In addition, more excellent affinity between the pressure-sensitive adhesive and the oil absorbent (especially, the oil absorbent that is a polymer compound having a plurality of alicyclic structures (particularly, alicyclic structures having no unsaturated bond)). In the re-peelable pressure-sensitive adhesive composition, it is possible to more effectively prevent unintended composition variations in the pressure-sensitive adhesive layer, and a more stable oil absorption function is exhibited at each part. The

As described above, the pressure-sensitive adhesive preferably includes a monomer having a saturated aliphatic hydrocarbon group having 5 or more carbon atoms as a constituent component, but the saturated aliphatic hydrocarbon group has 6 or more carbon atoms. Is more preferably 8 or more and 16 or less.
Thereby, the effects as described above are more remarkably exhibited.

The aliphatic hydrocarbon group may have a cyclic structure or a branched chain structure, but preferably has a linear structure.
Thereby, the effects as described above are more remarkably exhibited.

The proportion of the monomer having an aliphatic hydrocarbon group in the molecule (polymer) constituting the pressure-sensitive adhesive is preferably 50% by mass or more, and more preferably 60% by mass or more.
Thereby, the effects as described above are more remarkably exhibited.

  As a monomer which comprises an acrylic adhesive, the monomer which provides adhesiveness, the monomer which provides cohesive force, and the monomer which has a crosslinkable functional group are mentioned.

  Examples of the monomer that imparts tackiness include ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, and tetradecyl (meth) acrylate. .

  Examples of the monomer that imparts cohesive force include methyl (meth) acrylate, styrene, and vinyl acetate.

  As monomers having a crosslinkable functional group, monomers having a hydroxyl group such as 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, (meth) acrylic acid, etc. Examples thereof include monomers having a carboxyl group.

  Thereby, it is possible to make the adhesive itself more excellent in resistance to ultraviolet rays, and it is possible to more effectively prevent the deterioration of the adhesive and the problem of adhesive residue as described above.

  Moreover, the lipophilicity as the whole re-peelable pressure-sensitive adhesive composition (the whole pressure-sensitive adhesive layer) can be made more excellent. As a result, when the re-peelable pressure-sensitive adhesive composition includes an oil absorbent described in detail later, coupled with the effect of including the oil absorbent, the absorbed oil can be more favorably held inside, The effect of maintaining the adhesive strength when contacted can be further improved. In addition, more excellent affinity between the pressure-sensitive adhesive and the oil absorbent (especially, the oil absorbent that is a polymer compound having a plurality of alicyclic structures (particularly, alicyclic structures having no unsaturated bond)). In the re-peelable pressure-sensitive adhesive composition, it is possible to more effectively prevent unintended composition variations in the pressure-sensitive adhesive layer, and a more stable oil absorption function is exhibited at each part. The

  It is preferable that the content of the monomer having a polar group (for example, a hydroxyl group, a carboxyl group, an amino group, or a salt thereof) in the molecule (polymer) of the acrylic pressure-sensitive adhesive is sufficiently low.

  More specifically, the content of the monomer having a polar group in the molecule (polymer) of the acrylic pressure-sensitive adhesive is preferably 10% by mass or less, and more preferably 5% by mass or less.

Thereby, the lipophilicity as the whole re-peelable pressure-sensitive adhesive composition (the whole pressure-sensitive adhesive layer) can be made more excellent. As a result, when the re-peelable pressure-sensitive adhesive composition includes an oil absorbent described in detail later, coupled with the effect of including the oil absorbent, the absorbed oil can be more favorably held inside, The effect of maintaining the adhesive strength when contacted can be further improved.
As the adhesive, either a solvent type or an emulsion type may be used.

  The re-peelable pressure-sensitive adhesive composition preferably contains a cross-linked pressure-sensitive adhesive crosslinked with a cross-linking agent as the pressure-sensitive adhesive.

  Thereby, the cohesive force of an adhesive layer can be made more excellent and the adhesive residue at the time of peeling from a to-be-adhered body can be prevented more effectively.

  Examples of the crosslinking agent include aliphatic isocyanate compounds, aromatic isocyanate compounds, epoxy compounds, metal chelate compounds, aziridine compounds and other polyimine compounds, melamine resins, urea resins, dialdehydes, methylol polymers, metal alkoxides, metal salts. Etc. can be used. More specifically, for example, hexamethylene diisocyanate (HMDI) or an aliphatic isocyanate compound which is a derivative thereof, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, N, N, N ′, Epoxy compounds such as N′-tetraglycidyl-4,4-diaminodiphenylmethane, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, 1,3-bis (N, N-diglycidylaminomethyl) toluene And metal chelate compounds such as aluminum chelate compounds such as aluminum-isopropylate, aluminum-sec butyrate and aluminum acetylacetonate, and titanium chelate compounds such as tetraisopropyl titanate and tetrakis (2-ethylhexoxy) titanate.

  The amount of the crosslinking agent is not particularly limited, but is preferably 0.01 parts by mass or more and 2.0 parts by mass or less, and 0.03 parts by mass or more and 1.0 parts by mass with respect to 100 parts by mass of the polymer component of the adhesive main agent. More preferably, the amount is 0.05 parts by mass or more and 0.5 parts by mass or less.

  As a result, a more suitable adhesive force capable of performing re-peeling more appropriately is obtained, and the occurrence of a problem of adhesive residue can be more effectively prevented.

<Ultraviolet absorber>
The ultraviolet absorber has a function of absorbing ultraviolet rays.

  By including such an ultraviolet absorber, it is possible to effectively prevent deterioration of the adhesive due to ultraviolet rays (particularly, light in the ultraviolet region contained in external light such as sunlight), and an adhesive body (for example, an adhesive) It is possible to effectively prevent the problem of adhesive residue when the film or the like is peeled from the adherend.

As the ultraviolet absorber, for example, a compound having a conjugated unsaturated bond, particularly an aromatic compound can be suitably used.
Thereby, the absorption efficiency of ultraviolet rays can be further improved.

  Examples of the compound having a conjugated unsaturated bond include benzophenone ultraviolet absorbers, benzotriazole ultraviolet absorbers, triazine ultraviolet absorbers, salicylic acid ultraviolet absorbers, oxalic anilide ultraviolet absorbers, and cyanoacrylate ultraviolet rays. An absorbent etc. are mentioned.

  Examples of the benzophenone ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2,2 ′. -Dihydroxy-4-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, [2-hydroxy-4- (octyloxy) phenyl] ( Phenyl) methanone, bis (2-methoxy-4-hydroxy-5-benzoylphenyl) methane and the like.

  Examples of the benzotriazole ultraviolet absorber include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-5′-tert-butylphenyl) benzotriazole, 2- ( 2'-hydroxy-3 ', 5'-di-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2 -(2'-hydroxy-3 ', 5'-di-tert-butylphenyl) 5-chlorobenzotriazole, 2- (2'-hydroxy-3', 5'-di-tert-amylphenyl) benzotriazole, 2- (2′-hydroxy-4′-octoxyphenyl) benzotriazole, 2- [2′-hydroxy-3 ′-(3 ', 4' ', 5' ', 6' ',-tetrahydrophthalimidomethyl) -5'-methylphenyl] benzotriazole, 2,2'-methylenebis [4- (1,1,3,3-tetramethylbutyl ) -6- (2H-benzotriazol-2-yl) phenol], 2- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol, 2,2 '-Methylenebis [6- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol], 2- (2H-benzotriazol-2-yl) -p- Cresol, 2- (5-chloro-2H-benzotriazol-2-yl) -6-tert-butyl-4-methylphenol, [2 (2′-hydroxy-5′-methacryloxypheny ) -2H- benzotriazole.

  Examples of the triazine-based ultraviolet absorber include 2,4-bis (2-hydroxy-4-butoxyphenyl) -6- (2,4-dibutoxyphenyl) -1,3,5-triazine, 2,4, 6-tris (2-hydroxy-4-octyloxyphenyl) -1,3,5-triazine, 2,4,6-tris [2-hydroxy-4- (3-butoxy-2-hydroxypropyloxy) phenyl] -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-hexyloxy-3-methylphenyl) -1,3,5-triazine and the like.

  Examples of the salicylic acid-based ultraviolet absorber include phenyl salicylate, p-tert-butylphenyl salicylate, p-octylphenyl salicylate, and the like.

  Examples of the cyanoacrylate-based ultraviolet absorber include 2-ethylhexyl-2-cyano-3,3′-diphenyl acrylate, ethyl-2-cyano-3,3′-diphenyl acrylate, and the like.

  Moreover, as an ultraviolet absorber, inorganic materials, such as titania, can be used, for example. Inorganic materials (particularly titania) are particularly excellent in chemical stability and the like, and can exhibit a function of absorbing ultraviolet rays more stably over a longer period of time.

  Although the content rate of the ultraviolet absorber contained in a re-peeling-type adhesive composition is not specifically limited, It is preferable that they are 0.1 mass part or more and 10 mass parts or less with respect to 100 mass parts of adhesives. More preferably, it is 3 parts by mass or more and 5 parts by mass or less.

  If the content of the ultraviolet absorber is too low, the effect of including the ultraviolet absorber as described above may not be sufficiently exhibited depending on the type of the ultraviolet absorber. Moreover, when the content rate of a ultraviolet absorber is too high, the content rate of an adhesive will fall relatively and the function of an adhesive may not fully be exhibited.

<Oil absorbing material>
The re-peelable pressure-sensitive adhesive composition may include an oil absorbent having a function of absorbing oil.

  Thereby, when an adhesive body contacts with oil, oil can be efficiently absorbed and held, and the amount of oil present on the contact surface with the adherend can be reduced. As a result, even when it is in contact with oil, the adhesive force to the adherend can be suitably maintained.

  Examples of the oil include hydrocarbons having 5 or more carbon atoms, fatty acids having 5 or more carbon atoms, and ester compounds thereof (including fats and oils such as esters with polyhydric alcohols such as glycerin (for example, triglycerides)), Various silicone oils (for example, methicone, cyclomethicone, etc.) can be mentioned.

  In addition to mineral oil and synthetic oil, oil includes vegetable oil such as olive oil, sesame oil, jojoba oil, animal oil such as fish oil and lard.

  The oil absorbent material is any material that has the function of absorbing oil and taking the oil that has come into contact with the pressure-sensitive adhesive layer into the pressure-sensitive adhesive layer, or the function of retaining oil in the pressure-sensitive adhesive layer. However, for example, a porous body (including filler aggregates) having pores therein, a gelling agent that swells and gels by absorbing oil, and the like can be given.

  Such an oil absorbing material can take in oil into the oil absorbing material with higher efficiency, and can hold the state more appropriately. Therefore, by using such an oil absorbing material, the effects as described above are more remarkably exhibited.

  The porosity of the porous body is not particularly limited, but is preferably 10% by volume or more and 80% by volume or less, and more preferably 15% by volume or more and 70% by volume or less.

  As a result, more oil can be absorbed, the mechanical strength of the porous body can be improved, and the oil that has been absorbed more stably can be retained.

The porous body is preferably particulate.
When the porous body is in the form of particles as an aggregate, the average particle diameter (secondary particle diameter) of the porous body is preferably 0.1 μm or more and 30 μm or less, and 1.0 μm or more and 15 μm or less. It is more preferable that

  As a result, the dispersion stability and coating properties of the porous material in the re-peelable pressure-sensitive adhesive composition are excellent, and the occurrence of unintentional irregularities on the surface of the pressure-sensitive adhesive layer to be formed is more effectively achieved. Can be prevented.

  In this specification, the average particle diameter means a volume-based average particle diameter unless otherwise specified. For example, a dispersion liquid of a target particle is measured using a Coulter Counter particle size distribution measuring instrument (manufactured by COULTER ELECTRONICS INC). TA-II type etc.) and can be obtained by measuring using a 50 μm aperture.

  As a constituent material of the porous body, for example, calcium silicate, calcium carbonate, diatomaceous earth, silicon dioxide (silica), aluminum oxide (alumina), montmorillonite, kaolin and other clay minerals, various glasses, various metals, salt, etc. Inorganic compounds, low molecular organic compounds such as calcium lactate and lactose, starches such as dextrin, processed starch and porous starch, cellulose derivatives such as crystalline cellulose, methylcellulose and cellulose ether compounds, and polyvinyl alcohol.

  The porous body may be subjected to a surface treatment such as a hydrophobization treatment (lipophilic treatment).

  Thereby, the affinity between the porous body and the oil is improved, and the porous body can absorb the oil with higher efficiency.

In particular, in the case of a porous body, it is preferable that the inner wall surfaces of the pores are subjected to a hydrophobic treatment.
Thereby, the effect mentioned above is exhibited more notably.

  Examples of the hydrophobic treatment include a method of treating with a coupling agent such as a silane coupling agent and a titanate coupling agent, a metal soap treatment method using a zinc salt, a magnesium salt or an aluminum salt of a fatty acid. Can be mentioned.

  Further, as the oil absorbing material, a polymer compound having a plurality of alicyclic structures may be used in the repeating unit.

  Thereby, the affinity between the oil absorbing material and the oil is improved, and the oil absorbing material can absorb the oil with higher efficiency. Further, such an oil absorbent (particularly, a polymer compound having an alicyclic structure having no unsaturated bond) is a pressure-sensitive adhesive as described above (particularly, a saturated aliphatic hydrocarbon group having 5 or more carbon atoms). In particular, it has an excellent affinity with a polymer containing a monomer having a monomer as a constituent component), and the re-peelable pressure-sensitive adhesive composition has more unintentional variation in composition in the pressure-sensitive adhesive layer. This can be effectively prevented, and a more stable oil absorbing function is exhibited at each part.

  In particular, the oil absorbing material preferably has a chemical structure represented by the following formula (1).

（ただし、式（１）中、ｎは２以上の整数、ｍは１以上４以下の整数を示す。）

(In the formula (1), n represents an integer of 2 or more, and m represents an integer of 1 to 4)

  Thereby, the effects as described above are more remarkably exhibited.

  The re-peelable pressure-sensitive adhesive composition may include a plurality of types of oil absorbing materials. Thereby, these act synergistically and the effects as described above are more remarkably exhibited. In particular, when a plurality of types of oil absorbing materials having different action mechanisms are included (for example, when a porous body and a polymer compound having a plurality of alicyclic structures are included in a repeating unit), the above-mentioned The effect is even more pronounced. More specifically, for example, as an oil absorbent, a component mainly contributing to rapid oil absorption (for example, a polymer compound having a plurality of alicyclic structures in a repeating unit) and an adhesive layer Including components that have a function of storing absorbed oil (for example, porous bodies), the oil moves between these components, so that the oil can be absorbed quickly and the oil can exude for a long time. It is possible to achieve both prevention and stable effects.

  Although the content rate of the oil absorber contained in a re-peeling-type adhesive composition is not specifically limited, It is preferable that it is 0.1 mass part or more and 50 mass parts or less with respect to 100 mass parts of adhesives, 1 mass More preferably, it is more than 30 parts by mass and more preferably less than 5 parts by mass and less than 20 parts by mass.

  If the content of the oil absorbent is too low, the effects of including the oil absorbent as described above may not be sufficiently exhibited depending on the type of the oil absorbent. Moreover, when the content rate of an oil absorber is too high, the content rate of an adhesive will fall relatively and the function of an adhesive may not fully be exhibited.

<Plasticizer>
The re-peelable pressure-sensitive adhesive composition may contain a plasticizer.
Thereby, the softness | flexibility and elasticity of a re-peelable adhesive composition can be made more excellent. Moreover, the releasability of the pressure-sensitive adhesive layer formed using the re-peelable pressure-sensitive adhesive composition can be made more excellent, and a pressure-sensitive adhesive body produced using the re-peelable pressure-sensitive adhesive composition (for example, , The adhesive feeling when the adhesive film is peeled from the adherend can be made more excellent.

  Examples of plasticizers include phthalate plasticizers such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, di-n-octyl phthalate, and dicyclohexyl phthalate, trioctyl trimellitic acid, and trimellitic acid. Trimellitonate plasticizers such as triisononyl acid, triisodecyl trimellitic acid, 2-ethylhexyl trimellitic acid, polyester plasticizers such as phthalic acid polyester, phosphorus such as tricresyl phosphate, trioctyl phosphate, triphenyl phosphate Examples include acid ester plasticizers, epoxidized linseed oil, and epoxy plasticizers such as epoxidized butyl stearate, and those having an alkylene group having 4 or more carbon atoms in the molecule are preferred.

  Thereby, the tolerance to ultraviolet rays of the plasticizer can be further improved, and the pressure-sensitive adhesive layer formed by using the re-peelable pressure-sensitive adhesive composition as a whole. The resistance to UV rays can be made more excellent.

  Moreover, the lipophilicity as the whole re-peelable pressure-sensitive adhesive composition (the whole pressure-sensitive adhesive layer) becomes more excellent. As a result, in the case of including the plasticizer as described above together with the oil absorbing material, coupled with the effect of including the oil absorbing material, it is possible to hold the absorbed oil more suitably, in the case of contact with the oil The adhesive force retention effect can be further improved. In addition, the affinity between the plasticizer and the oil absorbent (in particular, the oil absorbent that is a polymer compound having a plurality of alicyclic structures (particularly, alicyclic structures having no unsaturated bonds)), and the plasticizer Affinity with an adhesive (especially an adhesive having a suitable chemical structure as described above) can be further improved, and reluctance in an adhesive layer in a re-peelable adhesive composition Variation in the composition can be more effectively prevented, and a more stable oil absorption function is exhibited at each part.

  Moreover, as a plasticizer, it is preferable to use what does not have an aromatic ring structure in a molecule | numerator.

  Thereby, the tolerance to ultraviolet rays of the plasticizer can be further improved, and the pressure-sensitive adhesive layer formed by using the re-peelable pressure-sensitive adhesive composition as a whole. The resistance to UV rays can be made more excellent.

  Moreover, the lipophilicity as the whole re-peelable pressure-sensitive adhesive composition (the whole pressure-sensitive adhesive layer) becomes more excellent. As a result, in the case of including the plasticizer as described above together with the oil absorbing material, coupled with the effect of including the oil absorbing material, it is possible to hold the absorbed oil more suitably, in the case of contact with the oil The adhesive force retention effect can be further improved. In addition, the affinity between the plasticizer and the oil absorbent (in particular, the oil absorbent that is a polymer compound having a plurality of alicyclic structures (particularly, alicyclic structures having no unsaturated bonds)), and the plasticizer Affinity with an adhesive (especially an adhesive having a suitable chemical structure as described above) can be further improved, and reluctance in an adhesive layer in a re-peelable adhesive composition Variation in the composition can be more effectively prevented, and a more stable oil absorption function is exhibited at each part.

  When the plasticizer is an ester compound of a polyvalent carboxylic acid component and an alcohol component, the alcohol component preferably has an alkyl group having 8 or more carbon atoms.

  Thereby, the lipophilicity as the whole re-peelable pressure-sensitive adhesive composition (the whole pressure-sensitive adhesive layer) becomes more excellent. As a result, when the plasticizer is included together with the oil absorbing material, coupled with the effect of including the oil absorbing material, the absorbed oil can be more favorably held inside, and the adhesive strength when in contact with the oil can be reduced. The holding effect can be further improved. In addition, the affinity between the plasticizer and the oil absorbent (in particular, the oil absorbent that is a polymer compound having a plurality of alicyclic structures (particularly, alicyclic structures having no unsaturated bonds)), and the plasticizer Affinity with an adhesive (especially an adhesive having a suitable chemical structure as described above) can be further improved, and reluctance in an adhesive layer in a re-peelable adhesive composition Variation in the composition can be more effectively prevented, and a more stable oil absorption function is exhibited at each part.

  Examples of the plasticizer that satisfies the above conditions include those having a chemical structure represented by the following formula (2) and the following formula (3).

（ただし、式（２）中、ｍは４以上の整数、ｌは８以上の整数を示す。）

(In the formula (2), m represents an integer of 4 or more, and l represents an integer of 8 or more.)

（ただし、式（３）中、ｌは８以上の整数を示す。）

(In the formula (3), l represents an integer of 8 or more.)

  By using such a plasticizer, the lipophilicity as the entire re-peelable pressure-sensitive adhesive composition (entire pressure-sensitive adhesive layer) is further improved. As a result, in the case of including the plasticizer together with the oil absorbing material, coupled with the effect of including the oil absorbing material, the absorbed oil can be more suitably held inside, and the adhesive strength when in contact with the oil can be reduced. The holding effect can be further improved. In addition, the affinity between the plasticizer and the oil absorbent (in particular, the oil absorbent that is a polymer compound having a plurality of alicyclic structures (particularly, alicyclic structures having no unsaturated bonds)), and the plasticizer Affinity with an adhesive (especially an adhesive having a suitable chemical structure as described above) can be further improved, and unwillingness in an adhesive layer in a re-peelable adhesive composition Variation in the composition can be more effectively prevented, and a more stable oil absorbing function is exhibited at each part.

  Such an effect is obtained by at least one of the plasticizer having the chemical structure represented by the above formula (2) and the plasticizer having the chemical structure represented by the above formula (3). In the case of using in combination with an oil absorbent, which is a polymer compound having an alicyclic structure having no unsaturated bond), and a pressure-sensitive adhesive containing a monomer having an aliphatic hydrocarbon group having 5 or more carbon atoms as a constituent component Is more prominent.

  Although the content rate of the plasticizer contained in the re-peelable pressure-sensitive adhesive composition is not particularly limited, it is preferably 1 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the adhesive, and 5 parts by mass or more and 25 parts by mass. It is more preferable that the amount is not more than part by mass.

  If the content of the plasticizer is too low, the effect of including the plasticizer as described above may not be sufficiently exhibited depending on the type of the plasticizer. Moreover, when the content rate of a plasticizer is too high, the content rate of an adhesive will fall relatively and the function of an adhesive may not fully be exhibited.

<Other ingredients>
The re-peelable pressure-sensitive adhesive composition may contain components other than those described above (other components). Examples of such components include various resins, curing catalysts, solvents, softeners, dyes, pigments and other colorants, anilide-based and phenol-based antioxidants, dispersants, leveling agents, antistatic agents, and the like. Can be mentioned.

  Examples of the light stabilizer include hindered amine light stabilizers and ultraviolet light stabilizers.

  Examples of the hindered amine light stabilizer include [bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate], bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate. Methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate and the like.

  Examples of the ultraviolet stabilizer include nickel bis (octylphenyl) sulfide, [2,2′-thiobis (4-tert-octylphenolate)]-n-butylamine nickel, nickel complex-3,5-di-tert- Examples thereof include butyl-4-hydroxybenzyl-phosphate monoethylate, nickel-dibutyldithiocarbamate, and benzoate type quenchers.

  The content of these components is not particularly limited, but it is preferable not to exceed 10% by mass as a whole of these components (other components) excluding the solvent.

[Adhesive]
Next, the pressure-sensitive adhesive body of the present invention will be described in detail.
<First Embodiment>
FIG. 1 is a schematic longitudinal sectional view showing a first embodiment of the pressure-sensitive adhesive body (pressure-sensitive adhesive film) of the present invention.

  As shown in FIG. 1, an adhesive film (removable adhesive film) 10 as an adhesive body includes a substrate 1 and a removable adhesive layer 2. And the adhesive layer 2 is comprised with the material containing an adhesive and the ultraviolet absorber which has a function which absorbs an ultraviolet-ray.

  Thereby, it is possible to provide the re-peelable pressure-sensitive adhesive film 10 that hardly causes adhesive residue when peeled from the adherend due to deterioration over time.

  In the present specification, the “adhesive film” includes the concept of an adhesive sheet, an adhesive tape, and an adhesive label.

The substrate 1 has a function of supporting the pressure-sensitive adhesive layer 2.
The substrate 1 may be in any form such as a dense body, a woven fabric, a nonwoven fabric, paper, a porous body, a synthetic paper such as polypropylene and polyester, and a foamed body.

  The constituent material of the substrate 1 is not particularly limited, and examples thereof include resin materials, metal materials, vegetable fibers such as pulp, animal fibers such as wool, and the like, and resin materials are preferably used.

  Examples of the resin material constituting the substrate 1 include polyolefins such as polyethylene and polypropylene; polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate and polyethylene naphthalate; acetate resin, acrylonitrile-butadiene-styrene copolymer (ABS) Resins, polystyrene, polyvinyl chloride and the like can be mentioned, and one or more selected from these can be used in combination. Moreover, as the base material 1, you may use the metal film formed by the vapor-phase film-forming method etc., for example, the thing provided with an aluminum vapor deposition film, for example.

  Moreover, the base material 1 may contain components other than those described above. Examples of such components include colorants such as dyes and pigments, antioxidants such as anilides and phenols, UV absorbers such as benzophenones and benzotriazoles, light stabilizers, modifiers, and rust prevention. Agents, fillers, surface lubricants, corrosion inhibitors, heat stabilizers, lubricants, antistatic agents, polymerization inhibitors, crosslinking agents, catalysts, plasticizers, leveling agents, thickeners, softeners, dispersants, etc. It is done.

  Moreover, the base material 1 may be comprised from a single layer, and the laminated body provided with a some layer may be sufficient as it. Moreover, the base material 1 may be comprised with the inclination material from which a composition changes in gradient in the thickness direction, for example.

  Moreover, in order to improve the adhesiveness with the adhesive layer 2, the primer layer can be formed in the base material 1, or a corona treatment etc. can be performed. Examples of the primer layer include acrylic, olefin, polyester, and polyurethane.

  Thereby, with respect to the adhesive force between the adhesive layer 2 and the adherend, the adhesive force between the substrate 1 and the adhesive layer 2 can be made particularly large, and the adhesive film 10 can be removed from the adherend. It is possible to more effectively prevent the pressure-sensitive adhesive layer 2 from being peeled off from the substrate 1 and remaining on the adherend during peeling.

  Although the thickness of the base material 1 is not specifically limited, It is preferable that they are 15 micrometers or more and 300 micrometers or less, and it is more preferable that they are 20 micrometers or more and 50 micrometers or less.

  The pressure-sensitive adhesive layer 2 only needs to be made of a material including a pressure-sensitive adhesive and an ultraviolet absorber having a function of absorbing ultraviolet rays. However, the pressure-sensitive adhesive layer 2 is preferably used by using the above-described re-peelable pressure-sensitive adhesive composition. Can be formed.

  Although the content rate of the ultraviolet absorber contained in the adhesive layer 2 is not specifically limited, It is preferable that it is 0.1 mass part or more and 5 mass parts or less with respect to 100 mass parts of adhesives, 0.3 mass part More preferably, it is 3 parts by mass or less.

  If the content of the ultraviolet absorber is too low, the effect of including the ultraviolet absorber as described above may not be sufficiently exhibited depending on the type of the ultraviolet absorber. Moreover, when the content rate of an ultraviolet absorber is too high, there exists a possibility that an ultraviolet absorber may remain on a to-be-adhered body.

  Although the content rate of the oil absorbent contained in the pressure-sensitive adhesive layer 2 is not particularly limited, it is preferably 0.1 parts by weight or more and 50 parts by weight or less with respect to 100 parts by weight of the pressure-sensitive adhesive. More preferably, it is 5 parts by mass or less and even more preferably 20 parts by mass or less.

  If the content of the oil absorbent is too low, the effects of including the oil absorbent as described above may not be sufficiently exhibited depending on the type of the oil absorbent. Moreover, when the content rate of an oil absorber is too high, the content rate of an adhesive will fall relatively and the function of an adhesive may not fully be exhibited.

  The thickness of the pressure-sensitive adhesive layer 2 is not particularly limited, but is preferably 1 μm or more and 100 μm or less, more preferably 3 μm or more and 50 μm or less, and further preferably 5 μm or more and 30 μm or less.

[Method for producing adhesive film]
Next, the manufacturing method of the adhesive film of this invention is demonstrated.

<First Embodiment>
FIG. 2 is a schematic longitudinal sectional view showing a first embodiment of a method for producing an adhesive body (adhesive film) of the present invention.

  The manufacturing method of this embodiment has the base material preparation process (1a) which prepares the base material 1, and the adhesive layer formation process (1b) which forms the adhesive layer 2 on the surface of the base material 1. .

  First, the base material 1 as described above is prepared (1a). Prior to the pressure-sensitive adhesive layer forming step, which will be described later, a primer layer as described above may be formed on the prepared substrate 1, or a corona treatment may be performed.

Next, the pressure-sensitive adhesive layer 2 is formed on the substrate 1 (1b).
Although the formation method of the adhesive layer 2 is not specifically limited, It can form suitably by providing the re-peeling-type adhesive composition mentioned above on one side of the prepared base material 1. FIG.

  Application of the re-peelable pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 2 includes, for example, a liquid re-peelable pressure-sensitive adhesive composition (coating liquid), roll coat, reverse coat, knife coat, die coat, and gravure. It can carry out by applying on the base material 1 by various coating methods such as coating and bar coating.

  In forming the pressure-sensitive adhesive layer 2, the re-peelable pressure-sensitive adhesive composition and other components may be mixed to adjust the coating liquid. For example, when the pressure-sensitive adhesive layer 2 is formed, the re-peelable pressure-sensitive adhesive composition may be mixed with water or a solvent.

  Examples of the solvent include ester solvents such as ethyl acetate and butyl acetate, ketone solvents such as methyl isobutyl ketone, methyl ethyl ketone, and cyclohexanone, and aromatic hydrocarbon solvents such as toluene and xylene, and the like. These can be used alone or in combination.

  The coating solution may be any coating solution, and the solid content concentration in the coating solution is not particularly limited, but is preferably 20% by mass or more and 70% by mass or less, and 25% by mass or more and 60% by mass or less. It is more preferable that

  The pressure-sensitive adhesive layer 2 may be once formed on a release liner and then bonded to the substrate 1.

[Packaging material (packaging body)]
Next, a packaging material (packaging body) to which the pressure-sensitive adhesive body of the present invention is applied will be described.

  FIG. 3 is a perspective view showing a preferred embodiment of the packaging body (wrapping material), and FIG. 4 is a sectional side view of the packaging body (wrapping material) shown in FIG. 3 in a closed state (when not used). 5 is a cross-sectional side view of the packaging body (wrapping material) shown in FIG. In the following description, the upper side in FIGS. 4 and 5 is referred to as “upper”, the lower side is referred to as “lower”, the left side in FIGS. 3 to 5 is referred to as “base end part”, and the right side is referred to as “tip part”. say.

  As shown in FIGS. 3 to 5, the packaging body P <b> 1 has a packaging material P <b> 2 and a storage item P <b> 10 stored in a space S formed inside the packaging material P <b> 2.

  The stored item P10 is a sheet (wet sheet) P11 impregnated with a liquid, and a plurality of sheets (for example, 6 sheets or more and 100 sheets or less) are stored in a state where the sheet P11 is folded as desired. Specific examples of the sheet P11 impregnated with liquid include wet tissue, makeup remover sheet, oil removing paper, medicinal paper, antibacterial paper, wiping cloth, automobile paper, window cleaning paper, toilet cleaning paper and the like.

  The liquid impregnated in the sheet P11 is appropriately determined depending on its use. For example, moisture, oil components (for example, cleansing oil, paraffin, liquid paraffin, wax, petrolatum, ceresin, montan wax, jojoba seed oil, castor Oil, etc.), volatile components such as alcohol, surfactants, lotions, moisturizing components such as glycerin, fragrances, antibacterial agents and the like. Among these, cleansing oils include those containing mineral oil and silicone oil.

  The packaging material P2 is composed of a packaging material main body P3 and a lid P4 as the base material 1. The packaging material main body P3 has a space S in which the stored item P10, that is, a plurality of sheets P11 is stored, and a sheet material P31 (film) having a desired shape is appropriately formed, joined, etc. It is what. For example, both ends of the cylindrical sheet material P31 are sealed by fusion (thermal fusion, high frequency fusion, ultrasonic fusion, etc.) or adhesion to form a sealing portion P32, It is a thing.

  The sheet material P31 is preferably a laminate of a resin material that does not transmit liquid or gas and a resin material that has fusibility.

Examples of the resin material that does not transmit liquid or gas include polyesters such as polyethylene terephthalate and polybutylene terephthalate.
Examples of the resin material having fusibility include polyolefins such as polyethylene, polypropylene, and ethylene vinyl acetate copolymer.

  Further, the sheet material P31 may be a single layer or a laminate of a plurality of layers. In the case where the sheet material P31 is composed of a laminated body, a laminate of two or more different resin layers among the resin materials exemplified above may be mentioned. Moreover, you may use what joined the metal layer (for example, metal foil, a metal vapor deposition layer, etc.) to the resin layer. Examples of the type of metal constituting the metal layer include aluminum, an aluminum alloy, and stainless steel.

  As described above, the sheet material P31 is formed of a laminated body, and in particular, the laminated body has a metal layer, thereby improving the gas impermeability (gas barrier property) of the sheet material P31 and imparting ultraviolet light impermeability. It is possible to improve the preservability of the stored item P10.

  Moreover, the sheet material P31 may be subjected to various surface treatments, for example, a surface treatment for improving adhesion with the pressure-sensitive adhesive layer 2. For example, the surface treatment for improving the adhesiveness and airtightness with the pressure-sensitive adhesive layer 2 is applied to at least a portion of the sheet material P31 to which the pressure-sensitive adhesive layer 2 is adhered (the upper surface of the outer peripheral portion P24 and the upper surface of the fractured portion P23). It may be given.

  Further, various functional layers such as a printing layer (printing coating layer) for printing characters and graphics, a protective layer, a layer for improving surface properties (such as gloss) are provided on the surface of the sheet material P31. It may be provided. Such a functional layer may also be provided on the upper surface of the lid P4.

  The thickness of the sheet material P31 is not particularly limited, but is preferably 15 μm or more and 500 μm or less, and more preferably 20 μm or more and 100 μm or less.

  When such a packaging material main body P3 is used, an opening P22 for taking out the sheet P11 which is the stored item P10 is formed. FIG. 4 shows a state when the package P1 is not used, that is, before the lid P4 is closed and the opening P22 is formed. As shown in FIG. 4, an easily breakable portion P <b> 21 including, for example, a half cut, a notch (a V-shaped groove), a perforation, and the like is linearly provided on the upper portion of the packaging body P <b> 3. The easily breakable portion P21 has a breaking strength smaller than other portions of the sheet material P31 (in the vicinity of the easily breakable portion P21), and when an external force is applied, the sheet material P31 is broken at the easily breakable portion P21 and opened. Is done. The easily breakable part P21 is formed in a shape corresponding to the outline of the opening P22 (for example, a circle, an ellipse, an oval shape, a rectangle), and after the easily breakable part P21 is broken, the easily breakable part of the sheet material P31 is broken. A portion surrounded by P21 (a portion inside the easily breakable portion P21) is a broken piece P23.

  The lid P4 is for closing the opening P22, and is made of a sheet material (film) having the same flexibility as the sheet material P31. Examples of the constituent material of the lid P4 include the same constituent materials as those of the base material 1 described above, and the preferable thickness thereof is the same as the thickness of the base material 1. In addition, the sheet material which comprises the cover body P4, and the sheet material P31 which comprises the packaging material P2 may differ in a constituent material and thickness.

  The lid P4 has a base end portion P41 located on the left side in FIG. 4, and has a tab P42 at the opposite end portion (tip end portion). The tab P42 is pinched with a finger, and the lid P4 is lifted upward from the tip side to form (open) the opening P22, or an operation of exposing the already formed opening P22 is performed. During this operation, the base end portion P41 of the lid body P4 does not peel off the pressure-sensitive adhesive layer 2 immediately below, and maintains the sticking state. Thereby, when taking out the sheet | seat P11 from the opening P22, the cover body P4 maintains the connection state with the packaging material main body P3 in the base end part P41.

  On the lower surface of the lid P4 (the surface on the side of the packaging material main body P3), an adhesive layer 2 described in detail later is formed (joined) by, for example, coating. The lid P4 is joined. The pressure-sensitive adhesive layer 2 is formed on a portion excluding the tab P42 on the lower surface of the lid P4.

  The bonding strength of the pressure-sensitive adhesive layer 2 to the lid P4 is larger (preferably 1.2 times to 50 times) than the bonding strength to the packaging material body P3. Thereby, when performing the operation of lifting the lid P4 from the tab P42 side and forming (opening) or exposing the opening P22, the pressure-sensitive adhesive layer 2 is maintained in a state of being joined to the lid P4 side, It peels from the packaging material main body P3. In particular, the adhesive residue on the packaging material main body P3 side, that is, the residue on the surface of the outer peripheral portion P24 of the pressure-sensitive adhesive composition constituting the pressure-sensitive adhesive layer 2 is also prevented.

  As shown in FIG. 4, when the package P1 is not used, the easily breakable portion P21 is not broken, and the adhesive layer 2 formed on the lid P4 is adhered to the upper surface of the packaging body P3. ing. The pressure-sensitive adhesive layer 2 is formed in a region including the easily breakable portion P21, that is, the opening P22 formed later. The pressure-sensitive adhesive layer 2 and the lid body P4 make the easily breakable portion P21 and its inner portion (breaking piece P23 and And the outer peripheral portion P24 of the easily breakable portion P21.

  From this state, when the tab P42 is pinched with a finger and the lid P4 is lifted upward from the tip side, as shown in FIGS. 3 and 5, the adhesive layer 2 is bonded to the lid P4 side. While maintaining, it peels from the packaging material body P3. At this time, the inner portion of the easily breakable portion P21, that is, the portion that becomes the broken piece P23 is maintained in a state of being stuck to the lower surface of the pressure-sensitive adhesive layer 2, and is lifted together with the lid P4. Breaking gradually, opening P22 is formed (opened). The pressure-sensitive adhesive layer 2 is peeled off at the outer peripheral portion P24 that is in the vicinity of the outside of the easily breakable portion P21. The pressure-sensitive adhesive layer 2 is left at the base end portion P41 of the lid P4 (the pressure-sensitive adhesive layer 2 at the base end portion P41 is maintained without being peeled off from the sheet material P31), and the pressure-sensitive adhesive layer 2 is peeled from the outer peripheral portion P24 of the easily breakable portion P21 of the sheet material P31, almost the entire easily breakable portion P21 is broken, and the broken piece P23 is adhered to the adhesive layer 2 (moves to the lid P4 side). Together with this, an opening P22 is formed. In this way, the packaging material P2 is opened.

  When the packaging material P2 is opened as described above, the uppermost sheet P11 of the stored items P10 can be picked with a finger and taken out from the opening P22. The sheets P11 are usually taken out one by one, but a plurality of sheets may be taken out simultaneously.

  After taking out the sheet P11, the lid P4 is returned to the original state (the state shown in FIG. 4). That is, the pressure-sensitive adhesive layer 2 is adhered again to the outer peripheral portion P24 (region surrounding the opening P22) of the opening P22 formed in the sheet material P31 located on the upper side of the packaging material main body P3. Thereby, the opening P22 is sealed. At this time, the broken piece P23 returns to the inside of the opening P22 to seal the opening P22, and the adhesive layer 2 is preferably closely adhered to the outer peripheral portion of the opening P22 of the sheet material P31, so that the packaging material P2 Sealability can be secured. This prevents the liquid impregnated in the stored item P10 from being volatilized and being scattered outside the packaging material P2 (the stored item P10 is dried) during subsequent storage. Further, it is possible to prevent dust, dust, bacteria, etc. from entering the packaging material P2 from the outside during storage and contaminating the stored item P10.

  Thus, when taking out the sheet P11 next time from the state in which the opening P22 is sealed with the lid P4 (the state shown in FIG. 4), the tab P42 is pinched with a finger and the lid P4 is moved upward from the front end side. When lifted up, the pressure-sensitive adhesive layer 2 is peeled from the outer peripheral portion P24 while maintaining the state of being bonded to the lid P4 side. Since the easily breakable portion P21 has already been broken, the broken piece P23 is also lifted together with the lid P4 while maintaining the state of being stuck to the adhesive layer 2, and the opening P22 is gradually exposed from the tip end side. When the pressure-sensitive adhesive layer 2 is peeled off from the outer peripheral portion P24 while leaving the pressure-sensitive adhesive layer 2 at the base end portion P41 of the lid P4, almost the entire opening P22 is exposed. In this way, the packaging material P2 is again opened. Thereby, the sheet | seat P11 in the uppermost part can be taken out again.

  After taking out the sheet P11, the pressure-sensitive adhesive layer 2 is adhered again to the outer peripheral portion P24 of the opening P22, and the lid P4 is closed (returns to the original state shown in FIG. 4). Thereby, the opening P22 is sealed again. Thus, although the operation | work which takes out the sheet | seat P11 in multiple times is performed, peeling and sticking from the outer peripheral part P24 of the adhesive layer 2 are performed whenever it takes out the sheet | seat P11. That is, in the package P1, peeling and sticking from the outer peripheral part P24 of the pressure-sensitive adhesive layer 2 are repeatedly performed (hereinafter referred to as “multiple peeling / sticking operations”). This number of times may correspond to the number of sheets P11 stored in the unused packaging material P2.

  The pressure-sensitive adhesive layer 2 is formed on the lower surface (back surface) of the lid body P4 with the lid body P4 as the base material 1. And the cover body P4 (base material 1) and the adhesive layer 2 comprise the adhesive film 10 which uses the packaging body main body P3 as an adherend.

  As mentioned above, although preferred embodiment of this invention was described, this invention is not limited to these.

  For example, the pressure-sensitive adhesive body (for example, pressure-sensitive adhesive film) may have at least one coating layer on the surface opposite to the surface facing the pressure-sensitive adhesive layer of the substrate. For example, the printed layer may be provided on the surface of the substrate opposite to the surface facing the pressure-sensitive adhesive layer. Moreover, in order to improve adhesiveness with a printing layer, the coating layer for printing etc. may be provided. Moreover, the coat layer which has functions, such as protecting the surface of an adhesive film, may be provided.

  Further, in the above-described embodiment, the case where the pressure-sensitive adhesive body is a pressure-sensitive adhesive film including a film-like base material and forming a film shape as the whole pressure-sensitive adhesive body has been representatively described. The shape is not limited to a film shape and may be any shape.

  Moreover, the laminate material may be coat | covered on the surface side opposite to the surface facing the adhesive layer of the said base material (adhesive film base material). As a laminating material, for example, a material provided with a laminate base material and an adhesive layer (laminate adhesive layer) can be used.

  Moreover, in this invention, although the ultraviolet absorber should just be contained in the adhesive layer at least, it may be contained in the other structure of an adhesive body further. For example, the ultraviolet absorber is applied to at least one of a base material (adhesive film base material) of an adhesive film as an adhesive body, a printing layer, and a laminate material (laminate base material, adhesive layer (laminate adhesive layer)). It may be included.

  In addition, the packaging material to which the pressure-sensitive adhesive body of the present invention is applied is not limited to the one having the above-described configuration, and may have any configuration as long as it accommodates a wet sheet.

  Hereinafter, the present invention will be described in more detail with reference to specific examples, but the present invention is not limited to these examples. In the following description, the treatment that does not particularly indicate the temperature condition is performed at room temperature (23 ° C.) and a relative humidity of 50%. Moreover, what does not show temperature conditions in particular also about various measurement conditions is a numerical value in room temperature (23 degreeC).

[1] Production of adhesive film (Example 1)
An acrylic copolymer (acrylic pressure-sensitive adhesive) having a monomer composition as shown in Table 1 and having a weight average molecular weight of 800,000, and 1,3-bis (N, N-di) as an epoxy-based crosslinking agent Glycidylaminomethyl) cyclohexane, 2- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol as an ultraviolet absorber, and a plurality of repeating units Quinton 1105 (manufactured by Nippon Zeon Co., Ltd.) as an oil absorbent, which is a polymer compound having an alicyclic structure, a compound represented by the following formula (4) as a plasticizer, and toluene as a solvent, A pressure-sensitive adhesive composition (removable pressure-sensitive adhesive composition) as a coating solution was prepared.

  Next, the above-mentioned pressure-sensitive adhesive composition was coated on a release liner (release paper) made of glassine using a knife coater so that the thickness after drying was 25 μm.

  Then, the solvent was removed by heating at 100 ° C. for 2 minutes, and the pressure-sensitive adhesive layer was formed by crosslinking at room temperature for 7 days.

  Next, a film-like base material made of polyethylene terephthalate having a thickness of 50 μm and having a corona treatment applied to the adhesive layer is bonded to the pressure-sensitive adhesive layer and aged for one week under conditions of a temperature of 23 ° C. and a relative humidity of 50%. Thus, an adhesive film in which the adhesive layer was protected with a release liner was obtained. The film thickness was measured with a micro gauge.

(Examples 2 to 8)
A pressure-sensitive adhesive film was produced in the same manner as in Example 1 except that the composition of the pressure-sensitive adhesive, the composition of the pressure-sensitive adhesive composition, and the structure of the pressure-sensitive adhesive film were as shown in Table 1.

(Comparative Example 1)
A pressure-sensitive adhesive film was produced in the same manner as in Example 8, except that the composition of the pressure-sensitive adhesive, the composition of the pressure-sensitive adhesive composition, and the structure of the pressure-sensitive adhesive film were as shown in Table 1.

  Table 1 shows the monomer composition of the pressure-sensitive adhesive (acrylic copolymer), the composition of the pressure-sensitive adhesive composition, and the structure of the pressure-sensitive adhesive film used in the production of the pressure-sensitive adhesive films of the above Examples and Comparative Examples.

  In Table 1, 2-ethylhexyl acrylate is M1, decyl acrylate is M2, tetradecyl acrylate is M3, butyl acrylate is M4, acrylic acid is M5, 2-hydroxyethyl acrylate is M6, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane as C1, 2- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol as UV absorber as UA1, Titania as UV absorber is UA2, 2,2'-methylenebis [6- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol as UV absorber ] Is UA3, 2- (2H-benzotriazol-2-yl) -p-cresol as a UV absorber is UA4 2- (5-Chloro-2H-benzotriazol-2-yl) -6-tert-butyl-4-methylphenol as UV absorber, UA5, Quinton 1105 as OA1, and silica as a porous material (AGC S-Tech) Sunsphere H-33, manufactured by the company, OA2, silica as a porous material (manufactured by Tosoh Silica, NIPSIL NS-T) as OA3, and hollow porous spherical fine particles of methyl methacrylate crosspolymer as a porous material ( Matsumoto Microsphere MHB-R) manufactured by Matsumoto Yushi Seiyaku Co., Ltd. is represented by OA4, the compound represented by the above formula (4) is represented by P1, and polyethylene terephthalate is represented by PET.

[2] Evaluation <Initial adhesive strength>
The pressure-sensitive adhesive films (pressure-sensitive adhesive films protected with a release liner) of each of the above examples and comparative examples were cut into a size of 25 mm wide × 150 mm long to obtain a test piece.

  The release liner was peeled from the obtained test piece, the exposed pressure-sensitive adhesive layer was brought into contact with a 100 μm-thick polyethylene terephthalate film, and the pressure-sensitive adhesive film (test piece) was brought into intimate contact with a 2 kg roll.

  The adhesive strength was measured in a 180 ° peel test in which the sample was left for 24 hours and then peeled off at a rate of 300 mm / min in the 180 ° direction using a tensile tester, and evaluated according to the following criteria. The film with A evaluation is the optimum adhesive strength as a re-peelable adhesive film, and is in the order of B, C, D, and E, and deviates from the range of preferable adhesive strength.

A: Adhesive strength is 4 N / 25 mm or more and less than 7 N / 25 mm.
B: Adhesive strength is 3 N / 25 mm or more and less than 4 N / 25 mm (except for the range of A)).
C: Adhesive strength is 2 N / 25 mm or more and less than 3 N / 25 mm (excluding ranges A and B).
D: Adhesive strength is 1 N / 25 mm or more and less than 2 N / 25 mm (excluding ranges of A, B, and C).
E: Adhesive strength is less than 1 N / 25 mm or 7 N / 25 mm or more.

<Initial adhesive residue>
About the polyethylene terephthalate film (polyethylene terephthalate film after peeling an adhesive film) used for evaluation of the said initial adhesive force, the site | part from which the adhesive film was peeled was observed and evaluated based on the following references | standards.

A: The area ratio of the portion where the adhesive residue of the adherend is pasted is less than 1%.
B: The area ratio of the portion where the adhesive residue is present in the portion where the adhesive film of the adherend is adhered is 1% or more and less than 20%.
C: The area ratio of the portion where the adhesive residue of the adherend is pasted is 20% or more and less than 40%.
D: The area ratio of the part where the adhesive residue is present in the part where the adhesive film of the adherend is pasted is 40% or more and less than 60%.
E: The area ratio of the portion where the adhesive residue of the adherend is pasted is 60% or more.

<Adhesive strength after UV irradiation>
The pressure-sensitive adhesive films (pressure-sensitive adhesive films protected with a release liner) of each of the above examples and comparative examples were cut into a size of 25 mm wide × 150 mm long to obtain a test piece.

  The release liner was peeled from the test piece, and the exposed adhesive surface was irradiated with ultraviolet rays for 10 hours using an ultraviolet fade meter U48 (manufactured by Suga Test Instruments Co., Ltd.).

  The test piece irradiated with ultraviolet rays was brought into contact with a polyethylene terephthalate film (adhered body), and the pressure-sensitive adhesive film (test piece) was brought into intimate contact by press-fitting once with a 2 kg roll.

  The adhesive strength was measured in a 180 ° peel test in which the sample was left for 24 hours and then peeled off at a rate of 300 mm / min in the 180 ° direction using a tensile tester, and evaluated according to the following criteria.

A: Adhesive strength is 4 N / 25 mm or more and less than 7 N / 25 mm.
B: Adhesive strength is 3 N / 25 mm or more and less than 4 N / 25 mm.
C: Adhesive strength is 2 N / 25 mm or more and less than 3 N / 25 mm.
D: Adhesive strength is 1 N / 25 mm or more and less than 2 N / 25 mm.
E: Adhesive strength is less than 1 N / 25 mm or 7 N / 25 mm or more.

<Adhesive residue after UV irradiation>
About the polyethylene terephthalate film (polyethylene terephthalate film after peeling an adhesive film) used for evaluation of the adhesive strength after the UV irradiation, the part where the adhesive film was peeled was observed and evaluated based on the following criteria.

A: The area ratio of the portion where the adhesive residue of the adherend is pasted is less than 1%.
B: The area ratio of the portion where the adhesive residue is present in the portion where the adhesive film of the adherend is adhered is 1% or more and less than 20%.
C: The area ratio of the portion where the adhesive residue of the adherend is pasted is 20% or more and less than 40%.
D: The area ratio of the part where the adhesive residue is present in the part where the adhesive film of the adherend is pasted is 40% or more and less than 60%.
E: The area ratio of the portion where the adhesive residue of the adherend is pasted is 60% or more.

<Adhesive strength after oil contact (peeling force)>
The pressure-sensitive adhesive films (pressure-sensitive adhesive films protected with a release liner) of each of the above examples and comparative examples were cut into a size of 25 mm wide × 150 mm long to obtain a test piece.

After applying cleansing oil containing mineral oil (mineral oil) and cyclomethicone (silicone oil) at 2 g / m ² on one surface of the polyethylene terephthalate film, the release liner was peeled from the test piece, and the exposed adhesive The agent layer was brought into contact and pressed in the same manner as described above.

  The adhesive strength was measured in a 180 ° peel test in which the sample was left for 24 hours and then peeled off at a rate of 300 mm / min in the 180 ° direction using a tensile tester, and evaluated according to the following criteria.

A: Adhesive strength is 4 N / 25 mm or more and less than 7 N / 25 mm.
B: Adhesive strength is 3 N / 25 mm or more and less than 4 N / 25 mm.
C: Adhesive strength is 2 N / 25 mm or more and less than 3 N / 25 mm.
D: Adhesive strength is 1 N / 25 mm or more and less than 2 N / 25 mm.
E: Adhesive strength is less than 1 N / 25 mm or 7 N / 25 mm or more.
These results are summarized in Table 2.

  As is apparent from Table 2, excellent results were obtained in the present invention, whereas satisfactory results were not obtained in the comparative example.

10 ... Adhesive film (removable adhesive film)
DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Adhesive layer P1 Packaging body P2 Packaging material P21 Easily fractured part P22 Opening P23 Broken piece P24 Outer peripheral part P3 Packaging material main body P31 Sheet material P32 Sealing part P4 Cover body P41 Base end part P42 Tab P10 Storage P11 sheet (wet sheet)
S space

Claims (9)

An adhesive applied to a packaging material for storing a wet sheet impregnated with a liquid,
A substrate;
A pressure-sensitive adhesive body comprising: a pressure-sensitive adhesive and a re-peelable pressure-sensitive adhesive layer containing an ultraviolet absorber having a function of absorbing ultraviolet rays.   The pressure-sensitive adhesive body according to claim 1, comprising a compound having a conjugated unsaturated bond as the ultraviolet absorber.   The pressure-sensitive adhesive body according to claim 1 or 2, wherein the content of the ultraviolet absorber relative to 100 parts by weight of the pressure-sensitive adhesive is 0.1 parts by mass or more and 10 parts by mass or less.   The pressure-sensitive adhesive body according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive layer includes an oil absorbent having a function of absorbing oil in addition to the pressure-sensitive adhesive and the ultraviolet absorber.   The pressure-sensitive adhesive body according to claim 4, wherein the oil absorbent is a polymer compound having a plurality of alicyclic structures in a repeating unit. The pressure-sensitive adhesive body according to claim 5, wherein the oil absorbent has a chemical structure represented by the following formula (1).

(In the formula (1), n represents an integer of 2 or more, and m represents an integer of 1 to 4)   The pressure-sensitive adhesive according to any one of claims 4 to 6, wherein the content of the oil absorbent relative to 100 parts by weight of the pressure-sensitive adhesive is 0.1 parts by weight or more and 50 parts by weight or less.   The pressure-sensitive adhesive according to any one of claims 1 to 7, wherein the pressure-sensitive adhesive contains a monomer having a saturated aliphatic hydrocarbon group having 5 or more carbon atoms as a constituent component.   The pressure-sensitive adhesive body according to any one of claims 1 to 8, wherein the pressure-sensitive adhesive layer further contains a plasticizer having an alkylene group having 4 or more carbon atoms in the molecule.

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