TW201418035A - Surface protection sheet - Google Patents

Abstract

Vided is a surface protection sheet wherein it is possible to inhibit "floating" or "peeling" from occurring between inner sheets and it is possible to easily peel off only the outer sheet when peeling off the outer sheet for the purpose of exposing the inner sheet. This surface protection sheet, in which n (n represents an integer of 2 or greater) layers of adhesive sheets having a base layer and an adhesive agent layer are laminated in the order of one to n, is characterized in that the adhesive agent layers of the first to (n-1)th adhesive sheets respectively come into contact with the base layers of the second to nth adhesive sheets, and the deflection amounts of the first to (n-1)th adhesive sheets are larger than the deflection amounts of the sides of second to nth adhesive sheets that respectively come into contact with the adhesive agent layer of the first to (n-1)th adhesive sheets.

Description

Surface protection sheet

The present invention relates to a sheet for surface protection.

In recent years, display devices such as liquid crystal displays (LCDs) or input devices such as touch panels used in combination with such display devices have been increasingly used in various fields. Various functional films are used in such display devices or input devices. For example, a film for surface protection for the purpose of protecting a surface, a hard coat film for the purpose of improving scratch resistance, and an antireflection film for the purpose of improving antireflection properties.

Usually, such a functional film is fixed using an adhesive or the like. For example, a laminated film including a transparent resin layer, an adhesive layer, and a peeling portion for peeling off the adhesive layer is known as a protective film for protecting a liquid crystal display unit of a mobile phone (see Patent Document 1). When the laminated film is damaged or the surface of the film is contaminated, the film of the outermost layer can be peeled off and removed to expose the inner film without dirt or damage.

Prior technical literature Patent literature

Patent Document 1: Japanese Patent Laid-Open Publication No. 2005-271412

In recent years, in the field of display devices or input devices, thinner and weaker adherends have been increasing. Therefore, the requirement for the laminated sheet is as follows: even if the adherend is thin or weak, the sheet on the inner side which is free from dirt or damage after being adhered to the adherend can be exposed as When the outer sheet is peeled off, it is easy to peel only the outer sheet, and it is possible to suppress "bumping" or "peeling" between the inner sheets. Further, in the field of a display device or an input device, it is required to be excellent in design from the viewpoint of design, etc., and if "bumping" or "peeling" occurs, the appearance is adversely affected.

Therefore, an object of the present invention is to provide a sheet for surface protection which can easily peel only the outer sheet when the outer sheet is peeled off for the purpose of exposing the inner sheet, and can be suppressed from the inner side. There is a "bump" or "peeling" between the sheets.

Further, another object of the present invention is to provide a sheet for surface protection which is excellent in appearance in addition to the above characteristics.

Therefore, the inventors of the present invention have conducted intensive studies and found that in the surface protective sheet in which the adhesive sheet having the base material layer and the adhesive layer is laminated, the adjacent adhesive sheet is selected under specific conditions. The adhesive sheet on the outer side can be easily peeled off, and the "bumping" or "peeling" between the adhesive sheets can be suppressed. The present invention has been completed based on these findings.

That is, the present invention provides a sheet for surface protection characterized in that the first to n (n is an integer of 2 or more) adhesive sheets having a base material layer and an adhesive layer are sequentially laminated with n layers. Further, the adhesive layers of the first to (n-1) adhesive sheets are in contact with the base layer of the second to n-th adhesive sheets, and the first to (n-1) adhesive sheets are as follows. The amount of bending is larger than the following predetermined amount of bending of the second to n-adhesive sheets adjacent to the side of the adhesive layer of the adhesive sheet.

Bending amount (mm): An adhesive sheet having a width of 20 mm and a length of 10 cm was fixed to a support table so that the protruding portion became a sheet having a width of 20 mm and a length of 8 cm, and was allowed to stand at 23 ° C for 1 minute, and then placed and measured. The free end of the protruding portion of the adhesive sheet The distance from the original position in the vertical direction is used to determine the amount of bending.

Preferably, the difference between the amount of bending of the first to (n-1) adhesive sheets and the amount of bending of the second to n-adhesive sheets adjacent to the adhesive layer side of the adhesive sheet is 1.0 mm or more. .

The thickness of the first to (n-1) adhesive sheets is preferably smaller than the thickness of the second to nth adhesive sheets adjacent to the side of the adhesive layer contacting the adhesive sheet.

Further, the present invention provides a sheet for surface protection characterized in that a first to n (n is an integer of 2 or more) adhesive sheet having a base material layer and an adhesive layer is sequentially laminated with n layers. And the adhesive layer of the first to (n-1) adhesive sheets is in contact with the base material layer of the second to n-th adhesive sheets, and the raw materials of the base layer of the first to n-adhesive sheets are shared, The composition of the adhesive layer of the first to n-adhesive sheets is shared, and the thickness of the first to (n-1) adhesive sheets is smaller than the second to n-adhesive sheets adjacent to the adhesive layer side of the adhesive sheet. The thickness.

The difference between the thickness of the first to (n-1) adhesive sheets and the thickness of the second to n-adhesive sheets adjacent to the adhesive layer side of the adhesive sheet is preferably in the range of more than 0 and 500 μm or less. Inside.

Preferably, the surface protection sheet has a release liner on the adhesive layer of the n-th adhesive sheet, the thickness of the release liner, the thickness of the (n-1)-adhesive sheet, and the n-th adhesive sheet. The relationship of the thickness is: (the thickness of the above-mentioned release liner) < (the thickness of the (n-1)th adhesive sheet) < (the thickness of the nth adhesive sheet).

Preferably, the surface protection sheet has a release liner on the adhesive layer of the nth adhesive sheet. The release liner has a thickness of 10 to 50 μm.

Furthermore, the present invention provides a structure in which the surface protection sheet is provided on the surface of the member.

When the sheet for surface protection of the present invention peels off the outer sheet for the purpose of exposing the inner sheet, it is possible to easily peel only the outer sheet, and it is possible to suppress the occurrence of "bumping" between the inner sheets or "Peeling." Further, the sheet for surface protection of the present invention is excellent in appearance.

1‧‧‧1st adhesive sheet

2‧‧‧2nd adhesive sheet

3‧‧‧3rd adhesive sheet

11‧‧‧Substrate layer

12‧‧‧Adhesive layer

13‧‧‧Release liner

41‧‧‧Support desk

42‧‧‧Adhesive sheets

421‧‧‧The prominent part of the adhesive sheet

F‧‧‧bending amount (bending distance, drooping distance)

N‧‧‧nth adhesive sheet

N-1‧‧‧(n-1) adhesive sheet

X‧‧‧Surface protection sheet X

Y‧‧‧Surface protection sheet Y

Z‧‧‧Surface protection sheet Z

Fig. 1 is a schematic cross-sectional view showing an example of a sheet for surface protection.

Fig. 2 is a schematic cross-sectional view showing an example of a sheet for surface protection.

Fig. 3 is a schematic cross-sectional view showing an example of a sheet for surface protection.

Fig. 4 is a schematic plan view showing an adhesive sheet fixed to a support table when the amount of bending of the adhesive sheet is measured.

Fig. 5 is a schematic cross-sectional view showing an adhesive sheet fixed to a support table when the amount of bending of the adhesive sheet is measured.

Fig. 6 is a schematic cross-sectional view showing the amount of bending of the adhesive sheet.

Hereinafter, the present invention will be specifically described using an embodiment of the present embodiment with reference to Figs. Furthermore, the invention is not limited to the aspects shown in the drawings.

(I) Sheet for surface protection

Fig. 1 is a cross-sectional view showing a schematic configuration of a sheet X for surface protection as an example of the embodiment. In addition, FIG. 2 is a cross-sectional view showing a schematic configuration of a sheet for surface protection Y according to another example of the embodiment, and FIG. 3 is a schematic view showing a configuration of a sheet Z for surface protection according to still another example of the embodiment. Sectional view. In addition, in this specification, "sheet" also means the meaning of "film" or "belt".

As shown in Fig. 1, the surface protection sheet X has a first to n (n is an integer of 2 or more) adhesive sheets (first adhesive sheet, second adhesive sheet, third adhesive sheet, ..., The (n-1)-adhesive sheet and the n-th adhesive sheet are formed by sequentially laminating n layers.

The first to nth adhesive sheets constituting the surface protective sheet X have a base material layer and an adhesive layer, and are provided on the outer surface of the adhesive layer of the n-th adhesive sheet as the outermost adhesive sheet. pad.

As shown in Fig. 1, in the surface protective sheet X, the adhesive layers of the first to (n-1) adhesive sheets are in contact with the base material layers of the second to n-th adhesive sheets, respectively.

The above-mentioned n is not particularly limited as long as it is an integer of 2 or more, and is preferably an integer of 2 to 20, more preferably an integer of 2 to 15, in terms of production cost, workability, and thinning. Good is an integer from 2 to 10. Further, since n is only required to be 2 or more, n may be 2.

Specifically, a sheet for surface protection Y having a structure in which three layers of the first to third adhesive sheets are sequentially laminated as shown in FIG. 2 can be obtained, and it can be formed as shown in FIG. The surface protection sheet Z having the structure in which the first to second adhesive sheets are laminated in two layers.

In the surface protective sheet X, the adhesive sheet (n-th adhesive sheet) corresponding to the innermost layer is provided with an adhesive surface which is used when the surface-protecting sheet is first attached to the adherend. Specifically, after the surface protection sheet X is attached to the adherend, first, the adhesive sheet (first adhesive sheet) corresponding to the outermost layer is protected from the adherend. Then, after the purpose of protecting the adhesive sheet (the first adhesive sheet) corresponding to the outermost layer is achieved, the adhesive sheet (the first adhesive sheet) corresponding to the outermost layer is peeled off, whereby the outermost layer can be separated. The adhesive sheet (second adhesive sheet) of the inner layer is exposed, and the adhesive sheet (second adhesive sheet) which is one inner side of the outermost layer is protected. As described above, the surface protective sheet X has a structure in which the adhesive sheet on the inner side is exposed by peeling off and removing the adhesive sheet on the outer side.

In the surface protection sheet X, the amount of bending of the first to (n-1) adhesive sheets is larger than the amount of bending of the second to nth adhesive sheets adjacent to the side of the adhesive layer contacting the adhesive sheet. With In the sheet X for surface protection, the amount of bending of the first adhesive sheet is larger than the amount of bending of the second adhesive sheet, and the amount of bending of the second adhesive sheet is larger than the amount of bending of the third adhesive sheet (not As shown in the figure, the amount of bending of the (n-1)th adhesive sheet is larger than the amount of bending of the nth adhesive sheet. According to this configuration, when the adhesive sheet on the outer side is peeled off for the purpose of exposing the inner adhesive sheet, the adhesive sheet on the outer side can be easily peeled off, and the "adhesion" between the adhesive sheets on the inner side can be suppressed. Or "peeling", so the appearance will be improved.

The method of measuring the above-described bending amount will be described below using FIGS. 4 to 6. 4 is a schematic plan view showing an adhesive sheet fixed to a support table when the amount of bending of the adhesive sheet is measured, and FIG. 5 is a schematic cross-sectional view showing the adhesive sheet fixed to the support table when the amount of bending of the adhesive sheet is measured. Fig. 6 is a schematic cross-sectional view showing the amount of bending of the adhesive sheet. As shown in FIG. 4 and FIG. 5, in the measurement of the amount of the bending, the adhesive sheet 42 having a width of 20 mm and a length of 10 cm to be measured is fixed to the support table such that the protruding portion has a sheet shape of a width of 20 mm and a length of 8 cm. 41. After standing at 23 ° C for 1 minute, as shown in Fig. 6, the distance f between the free end portion of the protruding portion 421 of the adhesive sheet 42 and the original position in the vertical direction was measured, thereby obtaining the amount of bending.

The amount of bending of the adhesive sheet can be adjusted, for example, by the thickness of the adhesive sheet, the thickness of the base material layer, the method of producing the adhesive sheet, the material constituting the base material layer, and the like. Specifically, in the surface protective sheet X, when the components of the adhesive layers of the first to n-adhesive sheets are shared, and the raw materials of the respective base layers of the first to n-adhesive sheets are shared, The amount of bending of the adhesive sheet can be controlled by the thickness of the adhesive sheet.

Therefore, the present invention may be a sheet for surface protection which is obtained by sequentially laminating n-layers of the first to n (n is an integer of 2 or more) adhesive sheets having a base material layer and an adhesive layer. And the adhesive layer of the first to (n-1) adhesive sheets is in contact with the base material layer of the second to n-th adhesive sheets, and the raw materials of the base layer of the first to n-adhesive sheets are shared, The composition of the adhesive layer of the first to n-adhesive sheets is shared, and the thickness of the first to (n-1) adhesive sheets is smaller than the second to n-adhesive sheets adjacent to the adhesive layer side of the adhesive sheet. It thickness".

Further, in the surface protective sheet, the raw materials of the base material layer are shared, and the main components of the raw material are also used in addition to the case where the raw materials of the base material layer are completely the same. For example, when the raw material of the base material layer is a polymer, when the main monomer components constituting the polymer are used in common, it can be judged that the raw materials of the base material layer are shared. More specifically, when the raw material of the base material layer is a polymer, the monomer component constituting the polymer accounts for 50% by weight or more (preferably 60% by weight) based on the total monomer component (100% by weight). When all of the above components, more preferably 70% by weight or more, further preferably 80% by weight or more, and particularly preferably 90% by weight or more, are used in common, it can be determined that the raw materials of the base material layer are shared. Further, in the above-mentioned surface protective sheet, the composition of the adhesive layer is common, and the main components are also used in addition to the case where the composition of the adhesive layer is completely the same. More specifically, the component (for example, a base polymer, an additive, etc.) contained in the adhesive layer accounts for 50% by weight or more (preferably 60% by weight or more, based on the total amount of the adhesive layer (100% by weight), More preferably, when all of the components of 70% by weight or more, more preferably 80% by weight or more, and particularly preferably 90% by weight or more are used in common, it is judged that the composition of the adhesive layer is common.

In the surface protection sheet X, the adhesive sheet can be more easily peeled off, and when the adhesive sheet is peeled off, the "bumping" or "peeling" between the adhesive sheets is further suppressed. (n-1) The difference between the amount of bending of the adhesive sheet and the amount of bending of the second to n-adhesive sheets adjacent to the adhesive layer side of the adhesive sheet is preferably 1.0 mm or more, and more preferably 3.0 mm. The above is further preferably 5.0 mm or more. Further, the upper limit of the difference in the amount of bending is not particularly limited, but is preferably 78 mm or less, more preferably 76 mm or less, still more preferably 72 mm or less.

In the surface protection sheet X, it is easier to peel off the adhesive sheet, and when the adhesive sheet is peeled off, the "bumping" or "peeling" between the adhesive sheets is further suppressed. -1) The thickness of the adhesive sheet is preferably smaller than the thickness of the second to n-adhesive sheets adjacent to the side of the adhesive layer contacting the adhesive sheet.

In particular, in the surface protective sheet X, the difference between the thickness of the first to (n-1) adhesive sheets and the thickness of the second to nth adhesive sheets adjacent to the adhesive layer side of the adhesive sheet is It is preferably in the range of more than 0 and 500 μm or less, more preferably in the range of 5 μm or more and 150 μm or less, and still more preferably in the range of 15 μm or more and 130 μm or less.

In the surface protective sheet X, the thickness of the first to n-adhesive sheets is not particularly limited, and is preferably in the range of 1 to 1000 μm, more preferably in the range of 5 to 500 μm, and further preferably 10~. Within the range of 200 μm.

The thickness of the entire surface protective sheet X is not particularly limited, and may be 2 to 2000 μm, preferably 5 to 1000 μm, more preferably 20 to 500 μm, still more preferably 40 to 260 μm, and particularly preferably 60 to 230 μm. . Furthermore, the overall thickness does not include the thickness of the release liner.

In the present embodiment, the surface protective sheet X having the first to nth adhesive sheets including the base layer and the adhesive layer is described as an example, but the present invention is not limited thereto. Composition. Other layers (the above-mentioned base material layer and layers other than the above-mentioned adhesive layer) may be provided between the base material layer and the adhesive layer as needed.

In the present embodiment, the surface of the adhesive layer of the n-th adhesive sheet is protected by a release liner, but the present invention is not limited to this configuration. For example, the back surface of the base material layer of the first adhesive sheet (the side opposite to the adhesive layer) may be subjected to a release treatment so that the peeled surface and the n-th adhesive sheet are adhered to each other. The form of winding in contact.

(base material layer)

The base material constituting the base material layer of the first to nth adhesive sheets is not particularly limited, and is preferably a plastic base material (polymer base material). The substrate may be a substrate including one layer, or may have a laminated structure of two or more layers.

The material constituting the plastic substrate is not particularly limited, and examples thereof include polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, and poly Polyester such as butylene naphthalate; polyolefin such as polyethylene, polypropylene, ethylene-propylene copolymer; polyvinyl alcohol; polyvinylidene chloride; polyvinyl chloride; vinyl chloride-vinyl acetate copolymer; Vinyl ester; polyamine; polyimine; cellulose; fluorine resin; polyether; polyether amide; polyether ether ketone; polyphenylene sulfide; polystyrene resin such as polystyrene; Ester; polyether oxime, etc. Further, the above materials may be used singly or in combination of two or more.

Among them, as a material constituting the plastic substrate, in terms of strength, handling, cost, dimensional stability, and good balance of gripping force, polyester is preferred, and polyethylene terephthalate is more preferred. Diester (PET).

The substrate may also be controlled for deformation by elongation treatment (uniaxial stretching or biaxial stretching) or the like. Moreover, in order to improve the adhesion to the adhesive layer, the surface of the substrate may be subjected to a conventional surface treatment such as chromic acid treatment, ozone exposure, flame exposure, high-voltage electric shock exposure, free radiation treatment, etc., using chemical or physical treatment. Method of oxidation treatment, etc.

Further, the substrate may be subjected to a primer treatment on the surface thereof. As the primer treatment, a primer treatment for improving the adhesion to the adhesive layer can be preferably used.

Further, in terms of improving the scratch resistance (friction resistance) of the surface, the substrate may be provided with a hard coat treatment. If such a hard coat layer is provided, the protective function of the sheet for surface protection can be further improved. Further, the hard coat layer may be a layer having high antireflection properties.

The pencil hardness of the surface (hard coat surface) of the hard coat layer is not particularly limited, but is preferably HB or more, and more preferably H or more. Further, the above pencil hardness can be measured in accordance with the scratch hardness test (pencil method) described in JIS K5600-5-4.

The hard coat layer is not particularly limited, and a known or conventional hard coat layer is exemplified. Examples of the resin component for forming the hard coat layer include a thermosetting resin such as a siloxane oxide resin, and an ester-based, acrylic, urethane-based or guanamine-based compound. An epi-radiation-hardening type resin (for example, an ultraviolet curable resin) of a type in which a monomer or oligomer such as a polysiloxane or an epoxy resin is subjected to a hardening treatment, acrylic acid-amino carboxylic acid The above-mentioned monomer or oligomer composite type free radiation curable resin (for example, ultraviolet curable resin) such as an ester type or an acrylic acid type or an epoxy type. Among the above, from the viewpoint of improving scratch resistance, a free radiation curable resin is preferred, and an ultraviolet curable resin is more preferred. That is, the hard coat layer is preferably a hardened film obtained by irradiating free radiation curable resin (especially ultraviolet curable resin) with free radiation (especially ultraviolet rays). Furthermore, the hard coat layer may have a single layer structure or a multi-layer (multilayer) structure. Further, the thickness of the hard coat layer is not particularly limited, and may be, for example, a known or customary thickness.

The base material may be, for example, a base material which is subjected to an undercoating treatment for improving the adhesion to the adhesive layer, and a hard coat layer is provided on the other surface.

The thickness of the substrate is not particularly limited, but is preferably 1 to 500 μm, more preferably 5 to 300 μm, still more preferably 10 to 200 μm. Further, the thickness of the base material includes the thickness of the hard coat layer or the like in the case where the hard coat layer is provided.

(adhesive layer)

The adhesive layer of the pressure-sensitive adhesive sheet is not particularly limited, and examples thereof include an acrylic pressure-sensitive adhesive layer, a rubber-based pressure-sensitive adhesive layer, a vinyl alkyl ether-based pressure-sensitive adhesive layer, a polyoxygen-based pressure-sensitive adhesive layer, and a polyester system. The adhesive layer, the polyamide-based adhesive layer, the urethane-based pressure-sensitive adhesive layer, the fluorine-based pressure-sensitive adhesive layer, the epoxy-based pressure-sensitive adhesive layer, and the like.

The above adhesive layer is formed of an adhesive composition. The above-mentioned adhesive composition may have any form, and may be, for example, an active energy ray-curing type, a solvent type (solution type), an emulsion type, a hot-melt type (hot melt type), or the like.

In particular, the adhesive layer is preferably an acrylic pressure-sensitive adhesive layer or a polyoxygen-based pressure-sensitive adhesive layer in terms of easy adhesion of the pressure-sensitive adhesive layer.

Further, it is preferable that the acrylic pressure-sensitive adhesive layer or the polyoxygen-based pressure-sensitive adhesive layer contains an acrylic polymer or a polyoxymethylene polymer as a base polymer with respect to the total amount (100% by weight) of the pressure-sensitive adhesive layer. 50% by weight or more, more preferably 60% by weight or more.

The polyoxygen-based adhesive layer is formed of a polyoxynitride-based adhesive composition. Make The polyoxynitride-based pressure-sensitive adhesive layer is not particularly limited, and examples thereof include a peroxide-crosslinked polyoxygen-based pressure-sensitive adhesive composition (peroxide-curable polyoxygen-based pressure-sensitive adhesive composition). The polyoxynoxy adhesive layer formed of the addition reaction type polyoxo-based adhesive composition may more preferably be a polyoxynoxy adhesive formed of an addition reaction type polyoxo-based adhesive composition. Floor.

Further, the polyoxyxide-based pressure-sensitive adhesive composition is preferably a phenyl group-containing polyoxynitride-based pressure-sensitive adhesive composition. The polyphenylene oxide-based pressure-sensitive adhesive composition containing a phenyl group may, for example, be a polymethylphenyl polyoxynene-based pressure-sensitive adhesive composition or a polyalkylphenylpolyoxygen-based pressure-sensitive adhesive composition or the like. A phenylpolyoxygen-based adhesive composition or the like.

The addition reaction type polyoxynoxy adhesive composition is preferably an addition reaction type polyoxynoxy adhesive composition using an organic polyoxyalkylene having a phenyl group (addition reaction type phenyl group) Polyoxygen adhesive composition). The organopolysiloxane having a phenyl group in the phenyl group-containing polyoxynitride-based pressure-sensitive adhesive composition of the above-mentioned addition reaction type, for example, polymethylphenyl decane (polymethylphenyl) Polyalkyl phenyl oxane (polyalkylphenyl fluorene oxide) such as polyoxymethane or polyethylphenyl siloxane (polyethyl phenyl fluorene oxide).

The addition reaction type polyoxo adhesive composition preferably contains a polyoxyxene rubber and a polyoxyxylene resin.

The polyoxyxene rubber is not particularly limited as long as it is a rubber component of a polyfluorene-based rubber, and is preferably an organic polysiloxane having a phenyl group (especially methylphenyl siloxane) as a main structure. a unit of organopolyoxane. Various functional groups such as a vinyl group may be introduced into the organopolyoxane in such a polyoxyxene rubber as needed. Further, the weight average molecular weight of the above organopolyoxyalkylene is not particularly limited, but is preferably 150,000 or more, more preferably 280,000 to 1,000,000, and still more preferably 500,000 to 900,000.

In addition, the polysiloxane resin is not particularly limited as long as it is a polyfluorene-based pressure-sensitive adhesive (polyoxygen-based pressure-sensitive adhesive), and examples thereof include organic polymerization as follows. a polyoxyalkylene oxide or the like which comprises a M unit selected from a structural unit "R ₃ -Si _1/2 ", a Q unit containing a structural unit "SiO ₂ ", and a structural unit. a (co)polymer of a T unit of "R-SiO _3/2 " and at least one unit of a D unit including a structural unit "R ₂ -SiO". Further, R in the above structural unit represents a hydrocarbon group or a hydroxyl group. Examples of the hydrocarbon group include an aliphatic hydrocarbon group (such as an alkyl group such as a methyl group or an ethyl group), an alicyclic hydrocarbon group (such as a cycloalkyl group such as a cyclohexyl group), and an aromatic hydrocarbon group (an aryl group such as a phenyl group or a naphthyl group). )Wait. The ratio (ratio) of the above-mentioned "M unit" to "at least one selected from the group consisting of the Q unit, the T unit, and the D unit" is preferably, for example, the former/the latter (Morby ratio) = 0.3/1 to 1.5/ 1 (preferably 0.5/1 to 1.3/1).

Various functional groups such as a vinyl group may be introduced into the organopolyoxane in the above polyoxyxylene resin as needed. Further, the functional group to be introduced may be a functional group capable of undergoing a crosslinking reaction. The weight average molecular weight of the organopolyoxane in the polyoxyxylene resin is preferably 1,000 or more, more preferably from 1,000 to 20,000, and still more preferably from 1,500 to 10,000.

The blending ratio of the polyoxyxene rubber and the polyoxyxene resin is not particularly limited, and it is preferably 100 to 220 parts by weight (particularly 120~) of the polyoxyxylene resin based on 100 parts by weight of the polyoxyxene rubber. 180 parts by weight).

Further, in the polyoxynitride-based adhesive composition containing the polyoxyxene rubber and the polyoxyxylene resin, the polyoxyxene rubber and the polyoxyxene resin may be in a mixed state of only mixing, or may be a mixture by the mixture. The polyoxyxylene rubber is reacted with a polyoxyxylene resin to form a condensed state of a condensate (particularly a partial condensate).

The polyoxygen-based adhesive composition may optionally contain an additive such as a crosslinking agent, a filler, a plasticizer, an anti-aging agent, an antistatic agent, or a colorant (pigment or dye). Further, a catalyst (especially a platinum-based catalyst or the like) may be contained. Further, the additives may be used singly or in combination of two or more.

In particular, in view of obtaining a polyoxynitride-based pressure-sensitive adhesive layer as a crosslinked structure, the polyoxyxylene-based pressure-sensitive adhesive composition containing the polyoxyxene rubber and the polyoxyxylene resin preferably contains a crosslinking agent. The crosslinking agent is not particularly limited, and a pyridoxane system is preferably used. A crosslinking agent (polyoxygenated crosslinking agent), a peroxide crosslinking agent, and the like. Further, the crosslinking agents may be used singly or in combination of two or more.

The above-mentioned oxyalkylene-based crosslinking agent is not particularly limited, and a polyorganohydrogen hydride having two or more hydrogen atoms bonded to a ruthenium atom in the molecule is preferably exemplified. In such a polyorganohydrogen hydride, a ruthenium atom to which a hydrogen atom is bonded may be bonded to various organic groups in addition to a hydrogen atom. Examples of the organic group include an alkyl group such as a methyl group or an ethyl group; an aryl group such as a phenyl group; and a halogenated alkyl group. Among them, from the viewpoint of synthesis or handling, an alkyl group is preferred, and a methyl group is more preferred. Further, the skeleton structure of the polyorganohydrogen hydride may have any one of a linear chain, a branched chain, and a cyclic structure, and is preferably linear.

As a commercial item of the above-mentioned polyoxyxide-based adhesive composition, for example, the product name "X-40-3306" (manufactured by Shin-Etsu Chemical Co., Ltd., addition reaction type polyoxygen-based adhesive composition) Wait.

On the other hand, as the adhesive layer of the adhesive sheet in the surface protective sheet of the present invention, the acrylic adhesive layer preferably contains an acrylic polymer as a base polymer. Further, the acrylic pressure-sensitive adhesive layer is formed of an acrylic pressure-sensitive adhesive composition.

The acrylic polymer is not particularly limited, and is preferably a polymer composed of an alkyl (meth)acrylate having a linear or branched alkyl group as a main monomer component. Further, the above "(meth)acrylic acid" means "acrylic acid" and/or "methacrylic acid" (either or both of "acrylic acid" and "methacrylic acid"), and the same applies.

The alkyl (meth)acrylate having a linear or branched alkyl group (hereinafter sometimes abbreviated as "alkyl (meth)acrylate") may, for example, be methyl (meth)acrylate. , ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, (meth)acrylic acid Dibutyl ester, tert-butyl (meth)acrylate, amyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, (methyl) ) octyl acrylate, (A) 2-ethylhexyl acrylate, isooctyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, decyl (meth) acrylate, (meth) acrylate Anthracene ester, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, (methyl) ) pentadecyl acrylate, cetyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, hexadecyl (meth) acrylate An alkyl (meth)acrylate having an alkyl group such as an ester or an amyl (meth)acrylate having 1 to 20 carbon atoms. Further, the alkyl (meth)acrylate may be used singly or in combination of two or more.

Wherein the alkyl (meth)acrylate is preferably an alkyl (meth)acrylate having an alkyl group of 2 to 10 carbon atoms, more preferably n-butyl (meth)acrylate (n-BA), 2-ethylhexyl acrylate (2EHA).

The content of the alkyl (meth)acrylate is not particularly limited, and is preferably 40 in terms of adhesion, based on the total amount of the monomer components (total weight, 100% by weight) constituting the acrylic polymer. The weight % or more (for example, 40 to 100% by weight), more preferably 50 to 99% by weight.

The acrylic polymer may contain a copolymerizable monomer as a constituent monomer component in terms of adjustability, use depending on the purpose, or function as needed. Further, the copolymerizable monomers may be used singly or in combination of two or more.

Examples of the copolymerizable monomer include a polar group-containing monomer. Examples of the polar group-containing monomer include (meth)acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, methacrylic acid, and the like (for example, maleic anhydride, and yacon). a carboxyl group-containing monomer such as an acid anhydride group-containing monomer such as an acid anhydride; 2-hydroxyethyl (meth)acrylate; 3-hydroxypropyl (meth)acrylate; 4-hydroxybutyl (meth)acrylate; a monomer having a hydroxyl group such as 6-hydroxyhexyl methacrylate, vinyl alcohol or allyl alcohol; (meth) acrylamide, N,N-dimethyl(meth) acrylamide, N-hydroxymethyl (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N-hydroxyethyl (A a guanamine-containing monomer such as acrylamide; an aminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, or a tert-butylaminoethyl (meth) acrylate An amine group-containing monomer; an epoxy group-containing monomer such as glycidyl (meth)acrylate or methyl glycidyl (meth)acrylate; a cyano group-containing monomer such as acrylonitrile or methacrylonitrile; ; N-vinyl-2-pyrrolidone, (meth) propylene Base Porphyrin, N-vinylpiperidone, N-vinylpipe , N-vinylpyrrole, N-vinylimidazole, vinylpyridine, vinylpyrimidine, vinyl a heterocyclic-containing vinyl monomer such as oxazole; a sulfonic acid group-containing monomer such as sodium vinylsulfonate; a phosphate group-containing monomer such as 2-hydroxyethyl acrylate; a cyclohexylmaleimide; A monomer containing an oxime imine group such as isopropyl maleimide; an isocyanate group-containing monomer such as 2-methylpropenyloxyethyl isocyanate or the like. Further, the polar group-containing monomers may be used singly or in combination of two or more.

Among them, the polar group-containing monomer is preferably a carboxyl group-containing monomer or a hydroxyl group-containing monomer, more preferably acrylic acid, 4-hydroxybutyl acrylate or 2-hydroxyethyl acrylate.

The content of the polar group-containing monomer is not particularly limited, and is preferably 1 to 20% by weight, and more preferably 1 to 15% by weight based on the total amount of the monomer component (100% by weight) constituting the acrylic polymer. %.

Further, examples of the copolymerizable monomer include polyfunctional monomers. The above polyfunctional single system means a monomer having two or more ethylenically unsaturated groups in one molecule. The ethylenically unsaturated group is not particularly limited, and examples thereof include radical polymerization of a vinyl group, a propenyl group, an isopropenyl group, a vinyl ether group (vinyloxy group), and an allyl ether group (allyloxy group). Sex functional group.

Examples of the polyfunctional monomer include hexanediol di(meth)acrylate, butanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, and (poly) Propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, Trimethylolpropane tri(meth) acrylate, tetramethylol methane tri(methyl) propylene An acid ester, allyl (meth) acrylate, vinyl (meth) acrylate, divinyl benzene, epoxy acrylate, polyester acrylate, urethane acrylate, and the like. Further, the above polyfunctional monomers may be used singly or in combination of two or more.

Further, examples of the copolymerizable monomer include alkoxyalkyl (meth)acrylate. The alkoxyalkyl (meth)acrylate is not particularly limited, and examples thereof include 2-methoxyethyl (meth)acrylate and 2-ethoxyethyl (meth)acrylate. Oxygen triethylene glycol (meth) acrylate, 3-methoxypropyl (meth) acrylate, 3-ethoxypropyl (meth) acrylate, 4-methoxy butyl (meth) acrylate Ester, 4-ethoxybutyl (meth)acrylate, and the like. Further, the alkoxyalkyl (meth)acrylate may be used singly or in combination of two or more.

Furthermore, as the above-mentioned copolymerizable monomer, in addition to the above-mentioned polar group-containing monomer, the above polyfunctional monomer, and the above (meth)acrylic alkoxyalkyl ester, for example, (methyl group) ) cyclopentyl acrylate, cyclohexyl (meth) acrylate, (meth) acrylate (meth) acrylate having an alicyclic hydrocarbon group or phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, benzyl (meth) acrylate or the like having an aromatic hydrocarbon group (methyl group) And an alkyl (meth)acrylate such as an acrylate; the alkoxyalkyl (meth)acrylate; the polar group-containing monomer; and a (meth)acrylate other than the polyfunctional monomer; Vinyl esters such as vinyl acetate and vinyl propionate; aromatic vinyl compounds such as styrene and vinyl toluene; olefins or dienes such as ethylene, butadiene, isoprene and isobutylene; Vinyl ethers such as ether; vinyl chloride and the like.

The acrylic polymer can be obtained by polymerizing the above monomer components by a known polymerization method. Examples of the polymerization method include a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, and a polymerization method (active energy ray polymerization method) using active energy ray irradiation. Among them, in terms of transparency, water resistance, cost, and the like, a solution polymerization method and an active energy ray polymerization method are preferred.

When the above acrylic polymer is formed, it can be used according to the kind of polymerization reaction. A polymerization initiator such as a thermal polymerization initiator or a photopolymerization initiator (photoinitiator). Further, the polymerization initiators may be used singly or in combination of two or more.

The above thermal polymerization initiator can be used, in particular, when the above acrylic polymer is obtained by solution polymerization. Examples of the thermal polymerization initiator include an azo-based initiator, a peroxide-based polymerization initiator (for example, dibenzoyl peroxide, tributyl methoxide peroxide, etc.), and redox. It is a polymerization initiator or the like. Among them, an azo-based initiator disclosed in JP-A-2002-69411 is especially preferred. The azo-based initiator is preferred because the decomposition product of the initiator is less likely to remain in the acrylic polymer as a cause of the gas (out gas) generated by heating. Examples of the azo-based initiator include 2,2'-azobisisobutyronitrile (hereinafter sometimes referred to as AIBN) and 2,2'-azobis(2-methylbutyronitrile) (hereinafter Sometimes referred to as AMBN), 2,2'-azobis(2-methylpropionic acid) dimethyl ester, 4,4'-azobis(4-cyanovaleric acid), and the like. The amount of the azo initiator to be used is preferably 0.05 to 0.5 parts by weight, more preferably 0.1 to 0.3 parts by weight, based on the total amount of the monomer component (100 parts by weight) constituting the acrylic polymer.

Further, the photopolymerization initiator can be used, in particular, when the acrylic polymer is obtained by active energy ray polymerization. The photopolymerization initiator is not particularly limited, and examples thereof include a benzoin ether photopolymerization initiator, an acetophenone photopolymerization initiator, an α-keto alcohol photopolymerization initiator, and an aromatic sulfonate.醯Chlorine photopolymerization initiator, photoactive oxime photopolymerization initiator, benzoin photopolymerization initiator, benzoin photopolymerization initiator, benzophenone photopolymerization initiator, ketal Photopolymerization initiator, 9-oxosulfur A photopolymerization initiator or the like.

Examples of the benzoin ether photopolymerization initiator include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and 2,2-dimethoxy-1,2-diphenyl. Ethyl-1-one, anisole methyl ether, and the like. Examples of the acetophenone-based photopolymerization initiator include 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, and 1-hydroxycyclohexylbenzene. Ketone, 4-phenoxydichloroacetophenone, 4-(t-butyl)dichloroacetophenone, and the like. Examples of the α-keto alcohol-based photopolymerization initiator include 2-methyl-2-hydroxypropiophenone and 1-[4-(2-hydroxyethyl)phenyl]-2-methylpropane-1. - Ketone and the like. Examples of the aromatic sulfonium chloride-based photopolymerization initiator include 2-naphthalenesulfonium chloride and the like. Examples of the photoactive oxime-based photopolymerization initiator include 1-phenyl-1,1-propanedione-2-(o-ethoxycarbonyl)-ruthenium. Examples of the benzoin-based photopolymerization initiator include benzoin and the like. Examples of the benzoin-based photopolymerization initiator include benzoin and the like. Examples of the benzophenone-based photopolymerization initiator include benzophenone, benzamidine benzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, and polyvinyl diamide. Benzophenone, α-hydroxycyclohexyl phenyl ketone, and the like. Examples of the ketal-based photopolymerization initiator include benzoin dimethyl ketal and the like. As the above 9-oxygen sulfur A photopolymerization initiator, for example, 9-oxosulfur 2-chloro-9-oxosulfur 2-methyl-9-oxosulfur 2,4-dimethyl-9-oxosulfur Isopropyl-9-oxosulfur 2,4-diisopropyl-9-oxosulfur Dodecyl-9-oxosulfur Wait.

The amount of the photopolymerization initiator to be used is not particularly limited, and is preferably 0.01 to 0.2 parts by weight, more preferably 0.05 to 0.15 by weight based on the total amount of the monomer components (100 parts by weight) constituting the acrylic polymer. Share.

The acrylic pressure-sensitive adhesive layer is formed of the above-mentioned acrylic pressure-sensitive adhesive composition, but the acrylic pressure-sensitive adhesive composition may further contain a crosslinking agent. By using the above-mentioned crosslinking agent, the acrylic polymer in the acrylic pressure-sensitive adhesive layer can be crosslinked to increase the cohesive force of the acrylic pressure-sensitive adhesive layer. Further, the crosslinking agents may be used singly or in combination of two or more.

Examples of the crosslinking agent include an isocyanate crosslinking agent, an epoxy crosslinking agent, a melamine crosslinking agent, a peroxide crosslinking agent, a urea crosslinking agent, and a metal alkoxide crosslinking. Agent, metal chelate crosslinking agent, metal salt crosslinking agent, carbodiimide crosslinking agent, An oxazoline crosslinking agent, an aziridine crosslinking agent, an amine crosslinking agent, and the like. Among them, an isocyanate crosslinking agent and an epoxy crosslinking agent are preferred.

Examples of the isocyanate-based crosslinking agent (polyfunctional isocyanate compound) include a low-grade such as 1,2-ethylidene diisocyanate, 1,4-butylene diisocyanate, and 1,6-hexamethylene diisocyanate. Aliphatic polyisocyanates; cyclopentadiene diisocyanates, cyclohexadiisocyanate, isophorone diisocyanate, hydrogenated toluene diisocyanate, hydrogenated xylene diisocyanate and other alicyclic polyisocyanates; 2,4-toluene diisocyanate, 2, An aromatic polyisocyanate such as 6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate or benzodimethyl diisocyanate. The isocyanate-based crosslinking agent may, for example, be a trimethylolpropane/toluene diisocyanate adduct (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name "Coronate L"), trishydroxyl Propane/hexamethylene diisocyanate adduct [manufactured by Japan Polyurethane Industry Co., Ltd., trade name "Coronate HL"], trade name "Coronate HX" (Japan Polyurethane Industry Co., Ltd.), trimethylolpropane / A commercial product such as a benzodimethyl diisocyanate adduct (manufactured by Mitsui Chemicals, Inc., trade name "Takenate 110N").

Examples of the epoxy-based crosslinking agent (polyfunctional epoxy compound) include N,N,N',N'-tetraglycidyl meta-xylylenediamine, diglycidylaniline, and 1,3- Bis(N,N-diglycidylaminomethyl)cyclohexane, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol II Glycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitol Anhydride polyglycidyl ether, trimethylolpropane polyglycidyl ether, diglycidyl adipate, diglycidyl phthalate, triglycidyl tris(2-hydroxyethyl)isocyanurate Further, resorcinol diglycidyl ether and bisphenol-S-diglycidyl ether may be used, and examples thereof include an epoxy resin having two or more epoxy groups in the molecule. Further, as the epoxy-based crosslinking agent, a commercially available product such as the product name "Tetrad C" (manufactured by Mitsubishi Gas Chemical Co., Ltd.) may be mentioned.

The content of the crosslinking agent in the acrylic pressure-sensitive adhesive composition is not particularly limited. For example, it is preferably 0.001 to 15 parts by weight, more preferably 0.01 to 12 parts by weight, based on the total amount of the monomer component (100 parts by weight) constituting the acrylic polymer.

In the acrylic pressure-sensitive adhesive composition, in addition to the above-mentioned crosslinking agent, a crosslinking accelerator, a decane coupling agent, an adhesion-imparting resin (rosin derivative, polyterpene resin) may be contained as needed within the range which does not impair the characteristics of the present invention. , petroleum resin, oil-soluble phenol, etc.), anti-aging agent, filler, colorant (pigment or dye, etc.), UV absorber, antioxidant, chain transfer agent, plasticizer, softener, surfactant, antistatic A known additive such as a agent or a stabilizer.

The adhesive sheet in the surface protective sheet of the present invention can be obtained by a known or conventional method of forming an adhesive layer. For example, the adhesive sheet having the above polyoxygen-based pressure-sensitive adhesive layer can be obtained by applying (coating) a polyoxynitride-based pressure-sensitive adhesive composition onto the base material layer, and drying it by heating and drying. Further, the adhesive sheet having the acrylic pressure-sensitive adhesive layer is not particularly limited, and can be obtained, for example, by the following methods (1) or (2).

(1) applying (coating) an acrylic pressure-sensitive adhesive composition containing an acrylic monomer mixture or a partial polymer thereof, and an optional photopolymerization initiator or a crosslinking agent to the substrate layer, and Irradiating the active energy ray to harden it to form an acrylic adhesive layer

(2) applying (coating) an acrylic pressure-sensitive adhesive composition (solution) containing an additive such as an acrylic polymer, a solvent, and an optional crosslinking agent to the base material layer, and drying and/or hardening Acrylic adhesive layer

Further, when the adhesive layer is formed, a drying step may be further provided as needed. Further, the adhesive sheet can also be produced by transferring a previously prepared adhesive layer onto a substrate layer.

Further, the coating (coating) of the above adhesive composition can be carried out by a known coating method. For example, a conventional coater (a gravure coater, a reverse roll coater, a contact roll coater, a dip roll coater, a bar coater, a knife coater, a spray can be used) Coating is carried out by a coater, a comma coater, a direct coater or the like.

The thickness of the pressure-sensitive adhesive layer (for example, the above-mentioned polyoxygen-based pressure-sensitive adhesive layer or the above-mentioned acrylic pressure-sensitive adhesive layer) is not particularly limited, but is preferably 5 to 100 μm, more preferably 5 to 90 μm, and still more preferably 10 to 10 75 μm.

(release liner)

In the surface protective sheet of the present invention, the release liner which can be used for the adhesive layer of the n-th adhesive sheet is not particularly limited, and a known or conventional release liner can be used.

For example, as the release liner for the above polyoxynitride-based adhesive layer, a plastic film containing the following components: polyethylene terephthalate (PET) or polyethylene naphthalate (PEN) can be preferably exemplified. ), polyester resin such as polybutylene terephthalate (PBT); polyethylene (PE), polypropylene (PP), polymethylpentene (PMP), ethylene-propylene copolymer, ethylene-vinyl acetate An olefin resin having an α-olefin as a monomer component such as an ester copolymer (EVA); polyvinyl chloride (PVC); a vinyl acetate resin; polycarbonate (PC); polyphenylene sulfide (PPS); Amidoxime resin such as amine (nylon) or wholly aromatic polyamine (aromatic polyamide); polyimide resin; polyether ether ketone (PEEK); polyethylene (PE), polypropylene (PP) Olefin-based resin; fluororesin such as polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, chlorofluoroethylene-vinylidene fluoride copolymer Wait.

Moreover, as a release liner used for the said acryl type adhesive layer, the peeling liner which has a peeling layer ( peeling process layer) on at least one surface of a release liner base material, and the low- A release liner, a release liner comprising a low polarity of a non-polar polymer, and the like. Further, a release liner substrate (that is, a release liner substrate itself) having no release layer may be mentioned. The fluorine-based polymer is not particularly limited, and examples thereof include polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, and chlorofluoroethylene. - a vinylidene fluoride copolymer or the like. In addition, the non-polar polymer is not particularly limited, and examples thereof include an olefin-based resin such as polyethylene (PE) or polypropylene (PP). Among them, it is preferable to use a release liner having a release layer on at least one surface of the release liner substrate, and a release liner substrate having no release layer (ie, a release liner) The substrate itself).

The release liner substrate is not particularly limited, and examples thereof include a plastic film and the like. Examples of such a plastic film include plastic films containing polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT). Polyester resin; polyethylene (PE), polypropylene (PP), polymethylpentene (PMP), ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), etc. Olefin resin of body composition; polyvinyl chloride (PVC); vinyl acetate resin; polycarbonate (PC); polyphenylene sulfide (PPS); polyamine (nylon), wholly aromatic polyamine (fang) A guanamine-based resin such as a polyamidoamine; a polyimide-based resin; a polyetheretherketone (PEEK) or the like. Among them, from the viewpoints of workability, availability, workability, dust resistance, cost, and the like, a plastic film formed of a polyester resin is preferable, and a PET film is further preferable.

The release treatment agent constituting the release layer is not particularly limited, and examples thereof include a polysulfonium-based release treatment agent, a fluorine-based release treatment agent, a long-chain alkyl release treatment agent, and a release treatment agent such as molybdenum sulfide. Among them, from the viewpoint of peeling control and stability over time, a polyoxynitride-based release treatment agent is preferred. Further, the release treatment agents may be used singly or in combination of two or more.

The release liner can be produced by a conventionally known method.

The thickness of the release liner is not particularly limited, and when the surface protection sheet is attached to the adherend, the release liner is peeled off to expose the adhesive surface, and the "bumping" or "peeling" between the adhesive sheets is suppressed. In terms of aspect, it is preferable to satisfy the following relationship.

(thickness of the above-mentioned release liner) <(th (n-1) thickness of the adhesive sheet) <(thickness of the n-th adhesive sheet)

Further, the thickness of the release liner is not particularly limited, and it is preferably 10 to prevent the occurrence of "bumping" or "peeling" between the adhesive sheets when the release liner is peeled off and the adhesive surface is exposed. 50 μm, more preferably 12 to 45 μm, further preferably 25 to 38 μm.

In particular, the release liner satisfies the following relationship (thickness of the release liner) <((n-1) thickness of the adhesive sheet) <(thickness of the n-th adhesive sheet)

Further, the thickness is particularly preferably 10 to 50 μm.

(Surface protection sheet)

Regarding the (n-1)-adhesive sheet of the surface-protecting sheet of the present invention, the polyethylene terephthalate is obtained in terms of sufficient adhesion to the n-th adhesive sheet and easy peelability. The adhesion of the ester film (PET film) is preferably from 0.1 to 9.0 gf/25 mm, more preferably from 0.2 to 5.0 gf/25 mm.

Furthermore, in the present specification, the adhesive force (180° peeling adhesion) (gf/25 mm) can be, for example, by using a tensile tester at 23 ° C, 50% RH, at a stretching speed of 300 mm/min. The adhesive sheet was peeled off from the adherend under the condition that the peeling angle was 180°.

The n-th adhesive sheet of the surface-protecting sheet of the present invention suppresses "bumping" or "peeling" between the adhesive sheets when the (n-1)-adhesive sheet is peeled off from the n-th adhesive sheet. In terms of obtaining sufficient adhesion to the adherend, the adhesion to the glass (glass plate) is preferably 0.5 to 30 gf / 25 mm, more preferably 1.5 to 15 gf / 25 mm.

In the n-th adhesive sheet of the surface protective sheet of the present invention, when the (n-1)th adhesive sheet is peeled off from the n-th adhesive sheet, the "bumping" or "peeling" is prevented between the adhesive sheets. In terms of obtaining sufficient adhesion to the adherend, the adhesion to aluminum (aluminum plate) is preferably 0.5 to 30 gf / 25 mm, more preferably 1.5 to 15 gf / 25 mm.

In particular, in the sheet for surface protection of the present invention, sufficient adhesion is obtained between the (n-1)th adhesive sheet and the nth adhesive sheet, and further, the peelability is further obtained, and N-1) When the adhesive sheet is peeled off from the nth adhesive sheet, the n-th adhesive sheet is further suppressed from being "bumped" or "peeled" between the adhesive sheets to improve the appearance. The adhesion of the material (for the glass plate, the stretching speed of 300 mm/min, and the peeling angle of 180°) is preferably greater than the adhesion of the (n-1)-adhesive sheet (for the PET film, the stretching speed of 300 mm/min, peeling) Angle 180°). Among them, the adhesion is poor [(the adhesion of the n-th adhesive sheet to the glass (glass plate)) - (the adhesion of the (n-1) adhesive sheet to the polyethylene terephthalate film (PET film) )] is preferably 0.1 gf / 25 mm or more, more preferably 0.5 gf / 25 mm or more.

Further, in the surface protective sheet of the present invention, sufficient adhesion is obtained between the (n-1)th adhesive sheet and the nth adhesive sheet, and further, the peeling property is further obtained, and (n-1) When the adhesive sheet is peeled off from the n-th adhesive sheet, the adhesion of the n-th adhesive sheet is further suppressed in terms of "bumping" or "peeling" between the adhesive sheets to improve the appearance. The aluminum plate, the stretching speed of 300 mm/min, and the peeling angle of 180° are preferably larger than the adhesion of the (n-1)th adhesive sheet (for the PET film, the stretching speed of 300 mm/min, and the peeling angle of 180°). Among them, the adhesion is poor [(the adhesion of the n-th adhesive sheet to aluminum (aluminum plate)) - (the adhesion of the (n-1) adhesive sheet to the polyethylene terephthalate film (PET film)) It is preferably 0.1 gf / 25 mm or more, more preferably 0.5 gf / 25 mm or more.

The sheet for surface protection of the present invention is not particularly limited and can be obtained by a known or customary method. For example, an adhesive sheet having a base material layer and an adhesive layer can be produced, and the adhesive sheet can be obtained by laminating n layers in a state in which the base material layer and the adhesive layer are in contact with each other.

Since the surface protection sheet of the present invention has a structure in which an adhesive sheet having a base material layer and an adhesive layer is laminated n layers, the surface can be protected by being attached to the adherend. First, the first adhesive sheet can be used for protection, and then the first adhesive sheet is peeled off to expose the second adhesive sheet, so that it can be protected by the second adhesive sheet. In this manner, the adhesive sheet of the next layer is peeled off by peeling one layer of the adhesive sheet, so that the adhesive sheet can be continuously protected by the adhesive sheet. For example, when the first adhesive sheet is damaged or stained by the first adhesive sheet, the first adhesive sheet can be peeled off and removed, so that no damage or dirt is cleaned. The second adhesive sheet is exposed, and the second adhesive sheet which is clean and non-destructive is continuously protected.

The adhesive sheet of the surface protection sheet of the present invention is excellent in adhesion and peeling property, and is excellent in suppressing "bumping" or "peeling" between the adhesive sheets which are produced when the adhesive sheet is peeled off. Therefore, the adhesive sheet of the surface protection sheet of the present invention is excellent in pick-up property. Therefore, the surface protective sheet of the present invention can effectively protect the surface thereof even if the adherend is thin and fragile.

Moreover, since the sheet for surface protection of the present invention is excellent in suppressing "bumping" or "peeling" between the adhesive sheets which are produced when the adhesive sheet is peeled off, it is excellent in appearance. Furthermore, if "bumping" or "peeling" occurs, the appearance will be adversely affected.

The surface protective sheet of the present invention can be used for a wide range of purposes. In particular, it can be preferably used for electrical or electronic machine applications (for example, surface protection applications in the manufacture of electrical or electronic machine machines, surface protection applications in the use of electrical or electronic machine machines, etc.). Further, it can be preferably used for optical applications (for example, surface protection applications in the manufacture of optical articles or optical members, surface protection applications in the use of optical articles or optical members, etc.).

The electric device is not particularly limited, and examples thereof include a refrigerator, a washing machine, and an outdoor unit of an air conditioner. In addition, the electronic device is not particularly limited, and examples thereof include image display devices such as liquid crystal displays and plasma displays, and mobile devices such as notebook personal computers.

The area of the adherend to be contacted with the n-th adhesive sheet of the sheet for surface protection is not particularly limited, and examples thereof include a plastic-containing region, a metal-containing region, and a glass. The area or the like, and more preferably the area containing the glass.

The above-mentioned optical article refers to a product which utilizes optical characteristics (for example, polarizability, light refraction, light scattering property, light reflectivity, light transmittance, light absorptivity, light diffraction property, light property, visibility, etc.) in the product. . Examples of the optical product include a liquid crystal display device, an organic EL (Electroluminescence) display device, a PDP (Plasma Display Panel), and a display device such as an electronic paper, or An input device such as a touch panel, or a device in which the display device and the input device are combined as appropriate.

The above optical member refers to a member having the above optical characteristics. Examples of the optical member include members constituting the display device (image display device), the input device, and the like (optical device), and members used in the devices, and examples thereof include a polarizing plate and a wave plate. Phase difference plate, optical compensation film, brightness enhancement film, light guide plate, reflective film, anti-reflection film, transparent conductive film (ITO (Indium Tin Oxides) film), new pattern film, decorative film, surface protection board,稜鏡, a lens, a color filter, a transparent substrate, or a member in which these layers are laminated (sometimes referred to collectively as "optical film"). In addition, the "plate" and the "film" respectively include a plate shape, a film shape, a sheet shape, and the like. For example, the "polarization film" includes a "polarizing plate" and a "polarized sheet". Further, as described above, the "optical member" of the present invention also includes a member that retains the visibility or the excellent appearance of the display portion in the display device or the input device and is responsible for adding decoration or protection (new film, Decorative film or surface protection film, etc.).

The material constituting the optical member is not particularly limited, and examples thereof include glass, acrylic resin, polycarbonate, polyethylene terephthalate, and metal (including metal oxide).

(II) Structure

The structure of the present invention has a configuration in which the surface protecting sheet is provided on the surface of the member. Examples of the structure include a structure in which the surface protection sheet is provided on the surface of an electric or electronic device, and a structure in which the surface protection sheet is provided on the surface of the optical product, and the surface of the optical member. A structure or the like provided with the sheet for surface protection described above is provided. In addition, as an electric or electronic device, an optical product, and an optical member, the above-mentioned "(I) sheet for surface protection" is mentioned.

Example

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited thereto. These embodiments. In the present embodiment, unless otherwise indicated, the parts by weight represent the values obtained by converting the solid content.

(Example of use of substrate 1)

A PET film (thickness: 25 μm, trade name "T100-25", manufactured by Mitsubishi Plastics Co., Ltd.) was used as the substrate constituting the base material layer.

Further, the PET film was referred to as "substrate (A)".

(Example of use of substrate 2)

As a base material constituting the base material layer, a PET film (thickness: 75 μm, trade name "T100-75", manufactured by Mitsubishi Plastics Co., Ltd.) was used.

Further, the PET film was referred to as "substrate (B)".

(Example of use of substrate 3)

As a base material constituting the base material layer, a PET film (thickness: 38 μm, trade name "T100-638", manufactured by Mitsubishi Plastics Co., Ltd.) was used.

Further, the PET film was referred to as "substrate (C)".

(Example 4 of the substrate)

As a base material constituting the base material layer, a PET film (thickness: 125 μm, trade name "Lumirror #125S10", manufactured by Toray Co., Ltd.) was used.

Further, the PET film was referred to as "substrate (D)".

(Preparation Example 1 of Adhesive Composition)

An addition reaction type polyoxynoxy adhesive (trade name "X-40-3306", manufactured by Shin-Etsu Chemical Co., Ltd.): 100 parts by weight and a platinum-based catalyst (trade name "CAT-PL-50T", (manufactured by Shin-Etsu Chemical Co., Ltd.): 0.2 parts by weight of the mixture was mixed to obtain a polyoxynitride-based adhesive composition.

Further, the polyoxynitride-based pressure-sensitive adhesive composition was referred to as "adhesive composition (A)".

(Preparation Example 2 of Adhesive Composition)

Butyl acrylate as a monomer component: 90 parts by weight, acrylic: 10 weight A portion and an ethyl acetate as a polymerization solvent: 150 parts by weight were placed in a separable flask, and the mixture was stirred for 1 hour while introducing nitrogen gas. After removing the oxygen in the polymerization system, the temperature was raised to 63 ° C, and 2,2'-azobisisobutyronitrile as a polymerization initiator was added: 0.2 part by weight, and reacted for 10 hours to add methyl ethyl ketone. An acrylic polymer solution having a solid content concentration of 25% by weight was obtained. The acrylic polymer in the above acrylic polymer has a weight average molecular weight of 650,000.

A crosslinking agent (trade name "Tetrad C", Mitsubishi Gas Chemical Co., Ltd., epoxy crosslinking agent) is added to the acrylic polymer solution in an amount of 11 parts by weight based on 100 parts by weight of the acrylic polymer. ), an acrylic adhesive composition was obtained.

This acrylic pressure-sensitive adhesive composition was referred to as "adhesive composition (B)".

(Preparation Example 3 of Adhesive Composition)

2-ethylhexyl acrylate as a monomer component: 100 parts by weight, 2-hydroxyethyl acrylate: 4 parts by weight, and ethyl acetate: 150 parts by weight as a polymerization solvent were placed in a separable flask. Stir for 1 hour while introducing nitrogen gas. After removing the oxygen in the polymerization system, the temperature was raised to 63 ° C, and 2,2'-azobisisobutyronitrile as a polymerization initiator was added: 0.2 part by weight, and reacted for 10 hours to add methyl ethyl ketone. An acrylic polymer solution having a solid content concentration of 25% by weight was obtained. The acrylic polymer in the above acrylic polymer has a weight average molecular weight of 550,000.

A crosslinking agent (trade name "Coronate HX", Japan Polyurethane Industrial Co., Ltd., isocyanate crosslinking agent) is added to the acrylic polymer solution in an amount of 4 parts by weight based on 100 parts by weight of the acrylic polymer. Further, dioctyltin dilaurate (trade name "OL-1", manufactured by Tokyo Fine Chemical Co., Ltd.) was added to obtain an acrylic resin in an amount of 0.015 parts by weight based on 100 parts by weight of the acrylic polymer. Adhesive composition.

This acrylic pressure-sensitive adhesive composition was referred to as "adhesive composition (C)".

(Example 1 of peeling liner)

As a release liner, the brand name "Diafoil MRF-25" (manufactured by Mitsubishi Plastics Co., Ltd., polyester film, thickness: 25 μm) was used.

This release liner is referred to as "release liner (A)".

Example 1

The adhesive composition (A) was applied to one surface of the above substrate (A), and dried at 130 ° C for 3 minutes to form an adhesive layer having a thickness of 10 μm. Then, a release liner (A) is provided on the adhesive layer. Thus, the first adhesive sheet was obtained. The first adhesive sheet has a laminated structure of a base material (A)/adhesive layer/release liner (A).

Next, the adhesive composition (A) was applied to one surface of the substrate (B), and dried at 130 ° C for 3 minutes to form an adhesive layer having a thickness of 75 μm. Then, a release liner (A) is provided on the adhesive layer. Thus, the second adhesive sheet was obtained. The second adhesive sheet has a laminated structure of a base material (B)/adhesive layer/release liner (A).

Then, the adhesive surface from which the release liner (A) of the first adhesive sheet is peeled off is adhered to the surface of the second adhesive sheet provided by the substrate (B) to obtain a laminated adhesive sheet. This laminated adhesive sheet has a laminated structure of a first adhesive sheet/second adhesive sheet/release liner (A).

Example 2

The adhesive composition (A) was applied to one surface of the above substrate (A), and dried at 130 ° C for 3 minutes to form an adhesive layer having a thickness of 10 μm. Then, a release liner (A) is provided on the adhesive layer. Thus, the first adhesive sheet was obtained. The first adhesive sheet has a laminated structure of a base material (A)/adhesive layer/release liner (A).

Next, the adhesive composition (C) was applied to one surface of the substrate (C), and dried at 130 ° C for 2 minutes to form an adhesive layer having a thickness of 21 μm. Then, a release liner (A) is provided on the adhesive layer. Thus, the second adhesive sheet was obtained. The second adhesive sheet has a laminated structure of a base material (C)/adhesive layer/release liner (A).

Then, the release liner (A) of the first adhesive sheet is peeled off and the adhesive surface is exposed. The laminated adhesive sheet was obtained by combining the surface of the second adhesive sheet provided by the substrate (C). This laminated adhesive sheet has a laminated structure of a first adhesive sheet/second adhesive sheet/release liner (A).

Example 3

The adhesive composition (A) was applied to one surface of the above substrate (A), and dried at 130 ° C for 3 minutes to form an adhesive layer having a thickness of 10 μm. Then, a release liner (A) is provided on the adhesive layer. Thus, the first adhesive sheet was obtained. The first adhesive sheet has a laminated structure of a base material (A)/adhesive layer/release liner (A).

Next, the adhesive composition (B) was applied to one surface of the above substrate (D), and dried at 130 ° C for 2 minutes to form an adhesive layer having a thickness of 20 μm. Then, a release liner (A) is provided on the adhesive layer. Thus, the second adhesive sheet was obtained. The second adhesive sheet has a laminated structure of a base material (D)/adhesive layer/release liner (A).

Then, the adhesive surface from which the release liner (A) of the first adhesive sheet is peeled off is adhered to the surface of the second adhesive sheet provided by the substrate (D) to obtain a laminated adhesive sheet. This laminated adhesive sheet has a laminated structure of a first adhesive sheet/second adhesive sheet/release liner (A).

Comparative example 1

The adhesive composition (C) was applied to one surface of the above substrate (C), and dried at 130 ° C for 2 minutes to form an adhesive layer having a thickness of 21 μm. Then, a release liner (A) is provided on the adhesive layer. Thus, the first adhesive sheet was obtained. The first adhesive sheet has a laminated structure of a base material (C)/adhesive layer/release liner (A).

Next, the adhesive composition (C) was applied to one surface of the substrate (C), and dried at 130 ° C for 2 minutes to form an adhesive layer having a thickness of 21 μm. Then, a release liner (A) is provided on the adhesive layer. Thus, the second adhesive sheet was obtained. The second adhesive sheet has a laminated structure of a base material (C)/adhesive layer/release liner (A).

Then, the adhesive surface on which the release liner (A) of the first adhesive sheet is peeled off is adhered to the surface of the second adhesive sheet provided by the substrate (C) to obtain a laminated adhesive sheet. This laminated adhesive sheet has a laminated structure of a first adhesive sheet/second adhesive sheet/release liner (A).

Comparative example 2

The adhesive composition (A) was applied to one surface of the above substrate (B), and dried at 130 ° C for 3 minutes to form an adhesive layer having a thickness of 75 μm. Then, a release liner (A) is provided on the adhesive layer. Thus, the first adhesive sheet was obtained. The first adhesive sheet has a laminated structure of a base material (B)/adhesive layer/release liner (A).

Next, the adhesive composition (A) was applied to one surface of the substrate (A), and dried at 130 ° C for 3 minutes to form an adhesive layer having a thickness of 10 μm. Then, a release liner (A) is provided on the adhesive layer. Thus, the second adhesive sheet was obtained. The second adhesive sheet has a laminated structure of a base material (A)/adhesive layer/release liner (A).

Then, the adhesive surface on which the release liner (A) of the first adhesive sheet is peeled off is adhered to the surface of the second adhesive sheet provided by the substrate (A) to obtain a laminated adhesive sheet. This laminated adhesive sheet has a laminated structure of a first adhesive sheet/second adhesive sheet/release liner (A).

(Evaluation)

The following measurements or evaluations were carried out on the examples and comparative examples. The results are shown in Table 1.

(Measurement of the amount of bending)

The amount of bending of the adhesive sheet is determined in accordance with the above [method for measuring the amount of bending].

(Measurement of adhesion)

The adhesive sheet (the first adhesive sheet or the second adhesive sheet) was cut into a sheet having a width of 20 mm and a length of 100 mm to prepare a test piece.

Then, the adhesive surface (measurement surface) of the test piece was pressure-bonded to the sheet-like adherend by a round trip of 2 kg, and aged for 30 minutes in an environment of 23 ° C and 50% RH. Thereafter, a universal tensile compression tester (device name "tensile compression tester TG-1kN", manufactured by Minebea Co., Ltd.) was used, and the tensile speed was 300 mm/min at 23 ° C and 50% RH. The test piece was peeled off from the adherend under a peeling angle of 180°, and the adhesive force (180° peeling adhesion) (gf/25 mm) was measured.

As an adherend, use PET film and glass plate (trade name "Micro Slide Glass" S", manufactured by Songlang Glass Industrial Co., Ltd., using non-tin surface), and aluminum plate (trade name "A1050P (extinction)", manufactured by Nippon Testpanel Co., Ltd.).

(Evaluation of pickup)

The release liner (A) of the laminated adhesive sheet is peeled off to expose the adhesive surface of the second adhesive sheet, and is pressed against the sheet-like adherend (aluminum plate) by reciprocating the 2 kg roller once. The aging was carried out for 30 minutes in an environment of 23 ° C and 50% RH. Thereafter, the first adhesive sheet of the laminated adhesive sheet was picked up by a pickup tape (trade name "BT-315ST", manufactured by Nitto Denko Corporation).

The situation at the time of picking was observed, and evaluation was performed according to the following criteria.

Evaluation basis

Good (○): The first adhesive sheet can be easily peeled off from the second adhesive sheet, and no "bumping" or "peeling" occurs between the adherend and the second adhesive sheet.

Defective (x): does not satisfy the above-mentioned good condition (for example, when the first adhesive sheet cannot be easily peeled off from the second adhesive sheet, and the first adhesive sheet cannot be peeled off from the second adhesive sheet, When the first adhesive sheet is peeled off from the second adhesive sheet, "bumping" or "peeling" occurs between the adherend and the second adhesive sheet, etc.)

When the above-mentioned pickup property was evaluated for the laminated adhesive sheet of the example, the release liner (A) was first peeled off from the second adhesive sheet. At this time, "bumping" or "peeling" did not occur between the first adhesive sheet and the second adhesive sheet. Moreover, the release liner (A) can be smoothly peeled off without causing breakage of the adhesive layer or the like.

According to the above evaluation of the pick-up property, the first adhesive sheet of the embodiment can be easily peeled off from the second adhesive sheet. The laminated adhesive sheets of the examples are excellent in appearance and design.

Industrial availability

The surface protective sheet of the present invention can be used for a wide range of purposes. In particular, it can be preferably used for electrical or electronic machine applications. Also, it can be preferably used for optical applications.

1‧‧‧1st adhesive sheet

2‧‧‧2nd adhesive sheet

11‧‧‧Substrate layer

12‧‧‧Adhesive layer

13‧‧‧Release liner

N‧‧‧nth adhesive sheet

N-1‧‧‧(n-1) adhesive sheet

X‧‧‧Surface protection sheet X

Claims (8)

A sheet for surface protection characterized in that the first to n (n is an integer of 2 or more) adhesive sheets of the base material layer and the adhesive layer are sequentially laminated with n layers, and the first layer is formed. The adhesive layer of the (n-1) adhesive sheet is in contact with the substrate layer of the second to n-adhesive sheets, respectively, and the bending amounts of the first to (n-1) adhesive sheets are respectively greater than the adjacent ones. The following bending amount of the second to n-adhesive sheets contacting the adhesive layer side of the adhesive sheet, the amount of bending (mm): an adhesive sheet having a width of 20 mm and a length of 10 cm so that the protruding portion has a width of 20 mm. The sheet having a length of 8 cm is fixed on the support table and placed at 23 ° C for 1 minute. After being placed, the distance between the free end portion of the protruding portion of the adhesive sheet and the original position in the vertical direction is measured. Find the amount of bending. The surface protection sheet according to claim 1, wherein the bending amount of the first to (n-1) adhesive sheets and the second to n adhesive sheets adjacent to the adhesive layer side of the adhesive sheet are the same The difference in the amount of bending is 1.0 mm or more. The surface protection sheet according to claim 1 or 2, wherein the thickness of the first to (n-1) adhesive sheets is smaller than the second to nth adhesive sheets adjacent to the side of the adhesive layer contacting the adhesive sheet, respectively. thickness. A sheet for surface protection characterized in that the first to n (n is an integer of 2 or more) adhesive sheets of the base material layer and the adhesive layer are sequentially laminated with n layers, and the first layer is formed. The adhesive layer of the ~(n-1) adhesive sheet is in contact with the substrate layer of the second to n-adhesive sheet, respectively. The raw material of the base layer of the first to n-adhesive sheets is shared, and the composition of the adhesive layer of the first to n-adhesive sheets is common, and the thickness of the first to (n-1) adhesive sheets is smaller than the adjacent contact. The thickness of the second to n-adhesive sheets on the adhesive layer side of the adhesive sheet. The surface protection sheet according to any one of claims 1 to 4, wherein the thickness of the first to (n-1) adhesive sheets and the second to n adhesions adjacent to the adhesive layer side of the adhesive sheet The difference in thickness of the sheet is in the range of more than 0 and 500 μm or less, respectively. The surface protection sheet according to any one of claims 1 to 5, wherein the adhesive layer of the nth adhesive sheet has a release liner, the thickness of the release liner, and the (n-1)th adhesive sheet The relationship between the thickness and the thickness of the n-th adhesive sheet is: (the thickness of the above-mentioned release liner) < (the thickness of the (n-1)th adhesive sheet) < (the thickness of the n-th adhesive sheet). The surface protection sheet according to any one of claims 1 to 6, wherein the adhesive layer of the n-th adhesive sheet has a release liner, and the release liner has a thickness of 10 to 50 μm. A structure for providing a surface protection sheet according to any one of claims 1 to 7 on the surface of the member.