JP2015196262A - Release film and adhesive body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a release film that can inhibit or prevent formation of a plurality of minute rugged parts (an orange peel-like surface) on an adhesive surface of an adhesive agent layer provided on the surface of a release agent layer, and to provide an adhesive body with the release film.SOLUTION: A release film according to the present invention is a release film peelably stuck to an adhesive agent layer, and includes a substrate 11 and a release agent layer 12 provided on one surface 111 side of the substrate 11. The surface free energy γof the release agent layer 12 satisfies the relationship of 11 [mJ/m]<γ<15 [mJ/m], and a dispersion component γin the surface free energy γsatisfies the relationship of 8 [mJ/m]<γ<11 [mJ/m].

Description

  The present invention relates to a release film and a pressure-sensitive adhesive body.

  Adhesive bodies are widely used for bonding and fixing various articles such as mobile terminal devices such as mobile phones and PDAs, electronic and optical parts such as digital cameras and digital video cameras.

  Such electronic / optical components are required to be light, thin, and small, and the pressure-sensitive adhesive used for assembly thereof is also required to be extremely thin.

  Such a pressure-sensitive adhesive body is usually composed of a pressure-sensitive adhesive layer and a release film attached to the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer in order to facilitate handling (see, for example, Patent Document 1).

  Such an adhesive has a problem that when the thickness of the pressure-sensitive adhesive layer is reduced in the manufacturing process, it is easy to cause scum on the adhesive surface. When the skin is present on the adhesive surface in this way, the skin is directly affected by the skin, so that it is difficult to use it for an optical component that requires visibility (for example, a screen such as a touch panel). In addition, even for electronic and optical parts that are not related to the appearance, the adhesive surface will be rough if there is a yuzu skin, so when bonded to the adherend, air will be involved in the interface, reducing the adhesive force and insufficient durability There was a risk of quality degradation. In particular, the occurrence of such crushed skin tended to occur frequently when the adhesive solution was thin and the viscosity of the adhesive solution was low.

  In general, in a double-sided pressure-sensitive adhesive body, release films are often laminated on both surfaces of the pressure-sensitive adhesive layer. In order to peel the release film from this double-sided adhesive type adhesive and use it smoothly, the peel strength of each release film must be different so that the other release film does not peel when peeling one release film. A way to have it is conceivable. Here, a lot of crushed skin that occurs on the adhesive surface generally occurs when an adhesive solution is applied to a light release type release film. Therefore, in the double-sided adhesive type adhesive body as described above, there is a tendency that the crushed skin on the adhesive surface is more frequently generated on the adhesive surface laminated on the release film on the light release force side.

JP 2011-6648 A

  An object of the present invention is to provide a release film capable of suppressing or preventing the formation of a plurality of minute irregularities (skin skin) on the adhesive surface of an adhesive layer provided on the surface of the release agent layer. Moreover, it is providing the adhesive body provided with this peeling film.

Such an object is achieved by the present inventions (1) to (5) below.
(1) A release film that is releasably attached to an adhesive layer,
A substrate;
A release agent layer provided on one surface side of the substrate,
The surface free energy γ _total of the release agent layer satisfies the relationship of 11 [mJ / m ² ] <γ _total <15 [mJ / m ² ],
A release film, wherein a dispersion component γ _d of the surface free energy γ _total satisfies a relationship of 8 [mJ / m ² ] <γ _d <11 [mJ / m ² ].

  (2) The peeling force P of the release agent layer is based on the 180 ° peel test specified in JIS-Z0237 and satisfies the relationship of 10 [mN / 25 mm] <P <50 [mN / 25 mm] ( The release film as described in 1).

(3) The polar component γ _p of the surface free energy γ _total satisfies the relationship of 0.5 [mJ / m ² ] <γ _p <5 [mJ / m ² ] (1) or (2 ) Release film.

  (4) The release film according to any one of (1) to (3), wherein the release agent layer does not contain silicone oil as a light release additive.

(5) a base material;
A release agent layer provided on one surface side of the substrate,
The surface free energy γ _total of the release agent layer satisfies the relationship of 11 [mJ / m ² ] <γ _total <15 [mJ / m ² ],
A release film satisfying a relationship in which a dispersion component γ _d of the surface free energy γ _total satisfies a relationship of 8 [mJ / m ² ] <γ _d <11 [mJ / m ² ];
A pressure-sensitive adhesive body comprising: a pressure-sensitive adhesive layer attached to a surface of the release agent layer opposite to the surface on which the substrate is provided.

  ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide the adhesive which can prevent that several micro unevenness | corrugations (skin skin) generate | occur | produce on the adhesive surface of the adhesive layer provided in the surface of a peeling agent layer. Become.

It is sectional drawing which shows 1st Embodiment of the peeling film concerning this invention. It is sectional drawing which shows 2nd Embodiment of the adhesive body concerning this invention. It is sectional drawing which shows 3rd Embodiment of the adhesive body concerning this invention. It is sectional drawing which shows 4th Embodiment of the adhesive body concerning this invention.

Hereinafter, preferred embodiments of the present invention will be described in detail.
<< First Embodiment >>
<Release film>
First, 1st Embodiment of the peeling film of this invention is described.

  FIG. 1 is a cross-sectional view showing a first embodiment of a release film according to the present invention. In the following description, the upper side in FIG. 1 is referred to as “upper” and the lower side is referred to as “lower”.

  A release film 10 shown in FIG. 1 is a laminate in which a release agent layer 12 and a substrate 11 are laminated.

  The release film 10 can be attached to the surface 121 side of the release agent layer 12 so that an adhesive layer (not shown) can be released.

Hereinafter, the base material 11 and the release agent layer 12 will be sequentially described.
<Substrate 11>
The substrate 11 has a function of imparting physical strength such as rigidity and flexibility to the release film 10.

  The material constituting the substrate 11 is not particularly limited. For example, a polyester resin such as polybutylene terephthalate resin, polyethylene terephthalate resin, polyethylene naphthalate resin, epoxy resin, phenol resin, urea resin, melamine resin, polyimide resin, A polyurethane resin etc. are mentioned, Among these, it can use 1 type or in combination of 2 or more types. Among these, from the viewpoint of ease of processing, durability, flexibility, and the like, it is preferable to use a polyester resin, and it is more preferable to use a polyethylene terephthalate resin.

  The substrate 11 may be a single layer film, or may be a multilayer film having two or more layers made of the same or different materials. This multilayer film may be obtained by laminating films formed in advance with an adhesive layer if necessary, or applying a resin composition on a pre-formed single layer film and drying the film. The resin layer obtained by this may be provided. The resin composition is not particularly limited. For example, an epoxy compound, an acrylate compound, a urethane acrylate compound, a polyester compound, or the like is used as a main agent, and if necessary, a crosslinking agent, a catalyst, a photopolymerization initiator, The thing containing a ultraviolet absorber etc. is mentioned. These resin compositions may have curability, and may be any of thermosetting, photocuring, electron beam curing, and the like. Thus, by using a multilayer film provided with a resin layer obtained by using a resin composition on a film formed in advance, the arithmetic average roughness Ra and the maximum protrusion height of the back surface (surface) 112 of the base material 11 are obtained. Rp can be more easily prepared.

  Moreover, the base material 11 may contain a filler. Examples of the filler include silica, titanium oxide, calcium carbonate, kaolin, and aluminum oxide.

  The thickness of the substrate 11 is not particularly limited, but is preferably 10 μm or more and 300 μm or less, and more preferably 15 μm or more and 200 μm or less.

  The surface of the substrate 11 has an arithmetic average roughness Ra of preferably 5 nm or more and 50 nm or less, more preferably 10 nm or more and 40 nm or less. In addition, the maximum height roughness Rp of both surfaces 111 and 112 is preferably 50 nm or more and 800 nm or less, and more preferably 100 nm or more and 400 nm or less. When a pressure-sensitive adhesive body is prepared using the release film 10 including the base material 11 having such a roughness shape, a pressure-sensitive adhesive layer having a smooth surface state can be obtained, which is suitable for optical applications and electronic component applications. An adhesive layer can be obtained. Moreover, it can prevent more effectively that it charges, when paying out the peeling film 10 (adhesive body) provided with the wound-up adhesive layer.

  The arithmetic average roughness Ra and the maximum protrusion height Rp can be measured according to JIS B 0601-1994 using a surface roughness measuring instrument SV3000S4 (stylus type) manufactured by Mitutoyo Corporation.

<Release layer 12>
As shown in FIG. 1, a release agent layer 12 is provided on the surface 111 side of the substrate 11. The release agent layer 12 has a function of imparting peelability to the release film 10.

  The release agent layer 12 is formed using a release agent layer forming composition containing a release agent. Specifically, the release agent layer 12 is formed by applying a release agent layer-forming composition containing a release agent to the surface 111 of the substrate 11 and drying it.

Hereinafter, this release agent layer forming composition will be described in detail.
(Composition for forming a release agent layer)
The release agent layer-forming composition contains a release agent as described above.

  The release agent is more preferably a silicone compound. Examples of the silicone compound include a silicone compound having dimethylpolysiloxane as a basic skeleton. Examples of the silicone compound include an addition reaction type, a condensation reaction type, an ultraviolet curable type, and an electron beam curable type. The addition reaction type silicone compound has high reactivity and excellent productivity, and has advantages such as little change in peel strength after production and no cure shrinkage compared to the condensation reaction type.

  As a specific example of the above addition reaction type silicone compound, two or more alkenyl groups having 2 to 10 carbon atoms such as vinyl group, allyl group, propenyl group, hexenyl group and the like are provided at the terminal and / or side chain of the molecule. Organopolysiloxane is mentioned. In general, in order to reduce the peel force, a technique for reducing the surface free energy by using a high molecular weight organovinylsiloxane and reducing the vinyl group content and the amount of crosslinking agent added is known. .

  When using an addition reaction type silicone compound, it is preferable to use a crosslinking agent and a catalyst in combination.

  Examples of the crosslinking agent include, for example, organopolysiloxane having hydrogen atoms bonded to at least two silicon atoms in one molecule, specifically, a dimethylhydrogensiloxy group end-capped dimethylsiloxane-methylhydrogensiloxane copolymer. , Trimethylsiloxy group end-capped dimethylsiloxane-methylhydrogensiloxane copolymer, trimethylsiloxy group end-capped methylhydrogenpolysiloxane, poly (hydrogensilsesquioxane), and the like.

  Examples of the catalyst include particulate platinum, particulate platinum adsorbed on a carbon powder carrier, chloroplatinic acid, alcohol-modified chloroplatinic acid, olefin complexes of chloroplatinic acid, and white metal compounds such as palladium and rhodium. It is done. By using such a catalyst, the curing reaction of the composition for forming a release agent layer can be advanced more efficiently.

  In addition to the silicone compound, the release agent layer forming composition may contain other components. Examples of other components include dyes, dispersants, antistatic agents, and the like. Moreover, when it contains another component, it is preferable that content of the other component in the composition for release agent layer forming is 0.1-20 mass%.

  Moreover, the release agent layer forming composition may contain a solvent, if necessary. Thereby, the viscosity of the composition for release agent layer formation at the time of apply | coating to the surface 111 of the base material 11 can be prepared easily. The solvent is removed by applying the release agent layer forming composition to the surface 111 of the substrate 11 and then drying.

  Examples of such solvents include aromatic hydrocarbons such as toluene, fatty acid esters such as ethyl acetate, ketones such as methyl ethyl ketone, and organic solvents such as aliphatic hydrocarbons such as hexane and heptane. One kind or a combination of two or more kinds can be used.

  Moreover, what is necessary is just to set content of the solvent in the composition for release agent layer formation suitably considering the application | coating (coating) property of the composition for release agent layer formation.

(Characteristic value of release agent layer 12)
Next, the characteristic value of the release agent layer 12 will be described.

  Here, since the pressure-sensitive adhesive layer can be obtained by applying and drying the composition for forming a pressure-sensitive adhesive layer on the surface (surface) 121, immediately after applying and drying the composition for forming a pressure-sensitive adhesive layer on the surface 121 Further, the skin skin observed on the surface of the pressure-sensitive adhesive layer can be reduced by improving the release agent layer 12.

  Further, the release agent component used for the release agent layer 12 is divided into a crosslinked component and an uncrosslinked component in a state after coating and drying. The uncrosslinked component is peeled off in a state where the release film 10 is wound up. It is easy to transfer to the back surface 112 of the film 10. The release agent component transferred to the back surface 112 is not transferred in a uniform amount with respect to the spread of the back surface 112 in contact, but there is a difference in the unevenness of the release film 10 and the winding tension. A large amount is transferred. As described above, when the release agent component is non-uniformly transferred to the back surface 112, the release agent component remaining in the release agent layer 12 also becomes non-uniform. If the release agent component that is easy to transfer is unevenly distributed on the surface (release surface) 121, the adhesive layer is formed on the surface 121 when the adhesive layer is formed on the surface 121 of the release film 10. In the composition for use, the wettability is disturbed at the boundary of distribution (interface between the release agent layer 12 and the pressure-sensitive adhesive layer). This is considered to be a cause of causing a crushed skin in the adhesive layer.

In the release film of the present invention, the surface free energy γ _total of the release agent layer satisfies the relationship of 11 [mJ / m ² ] <γ _total <15 [mJ / m ² ] and the surface free energy γ _total is The dispersion component γ _{d of which} has a release agent layer that satisfies the relationship of 8 [mJ / m ² ] <γ _d <11 [mJ / m ² ] exhibits the effect of suppressing the generation of crusty skin. can do.

When the release agent layer 12 satisfies the surface free energy γ _total and the dispersion component γ _d within the above ranges, the number of uncrosslinked components in the vicinity of the surface 121 of the release agent layer 12 is reduced. By reducing the amount of uncrosslinked components in the vicinity of the surface 121, the amount of uncrosslinked components transferred to the back surface 112 of the release film 10 is reduced, and thus the unevenness of the release components of the release agent layer 12 is inevitably eliminated. Is done. As a result, the adhesive layer provided on the release film 10 is suppressed from generating crushed skin on the adhesive surface during production.

In general, when silicone oil is added to the release agent layer, the release force can be kept low, so it is often used for a light release type release agent layer. However, silicone oil is a component that increases the dispersion component γ _d and does not have a crosslinkable functional group, so that it is easily transferred to the back surface of the release film. Therefore, in the state of the release film roll, the silicone oil is partially transferred to the back side, and the silicone oil is unevenly present on the surface side of the release agent layer. As a result, it is easy to generate a crushed skin on the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer obtained by applying and drying a low-viscosity pressure-sensitive adhesive layer-forming composition on the surface of the peeled release film.

However, as described above, the silicone oil can keep the release force of the release agent layer low, and is effective in obtaining a light release type release agent layer. Therefore, as in this embodiment, after satisfying the surface free energy γ _total and the dispersion component γ _d within the above ranges, if no silicone oil is added to the release agent layer 12, the effect of eliminating the sullen skin is obtained. Further improvement can be achieved.

  “No silicone oil added” means that the silicone oil content in the release agent layer-forming composition is less than 0.1 mass%.

  Moreover, the release agent component that is easily transferred to the back surface 112 of the release film 10 is also easily transferred to the pressure-sensitive adhesive layer, and the silicone contained in the release agent layer 12 is transferred to the pressure-sensitive adhesive layer. Adhesiveness may be adversely affected. In view of such influence, the amount of silicone transferred from the release agent layer 12 to the pressure-sensitive adhesive layer is preferably 70 cps or less, more preferably 60 cps or less, and even more preferably 45 cps or less. If the amount of silicone transferred to the pressure-sensitive adhesive layer is within the above range, an undesired decrease in the pressure-sensitive adhesive property of the pressure-sensitive adhesive layer can be suppressed.

  The lower limit value of the amount of silicone transferred from the release agent layer 12 to the pressure-sensitive adhesive layer is not particularly limited, but is preferably 15 cps or more, and more preferably 20 cps or more.

  The amount of silicone transferred can be evaluated by the amount of silicon atoms (unit: cps (count per second)) measured using a fluorescent X-ray (Rigaku desktop wavelength dispersive fluorescent X-ray analyzer Mini-Z). .

Here, the surface free energy γ _total described above is the sum (total) of three different components, ie, the dispersion component γ _d , the polar component γ _p , and the hydrogen bond component γ _h . That is, the surface free energy γ _total is a value represented by γ _total = γ _d + γ _p + γ _h .

In addition, the surface free energy γ _total and each component (dispersion component γ _d , polar component γ _p , hydrogen bond component γ _h ) use water, diiodomethane, and bromonaphthalene, which have known contact angles, as probe liquids. The contact angle of each probe solution was measured with a meter (manufactured by Kyowa Interface Science Co., Ltd., fully automatic contact angle meter DM-701). Magazine, Vol.8, No.3, 1972, pp.131-141).

The release agent layer 12 has the surface free energy γ _total thus derived is 11 [mJ / m ² ] <γ _total <15 [mJ / m ² ], and the dispersion component γ of the surface free energy γ _{total When d} is 8 [mJ / m ² ] <γ _d <11 [mJ / m ² ], the release force of the release agent layer 12 to the pressure-sensitive adhesive layer is appropriate as a light release type, and the surface layer has not yet been removed. This is a state in which the crosslinking component is reduced. For this reason, the transfer of the release agent component to the back surface 112 of the release film 10 is suppressed, and the occurrence of crushed skin hardly occurs when the adhesive layer forming composition is applied (applied).

On the other hand, when the dispersion component γ _d is less than the lower limit value, the pressure-sensitive adhesive layer is easily peeled off unintentionally from the release agent layer 12. On the other hand, when the dispersion component γ _d exceeds the upper limit, the release agent layer 12 is in close contact with the pressure-sensitive adhesive layer more than necessary. Therefore, for example, when a heavy release type release film is provided on the side opposite to the release film 10 of the adhesive layer, it is difficult to provide a difference between the release force of the release film 10 and the release force of the heavy release type release film. Become. As a result, it becomes difficult to peel the release film 10 smoothly. Moreover, it becomes easy to produce a bruise skin on the surface (adhesive surface) which is contacting the release agent layer 12 of the adhesive layer.

The release agent layer 12 may have a surface free energy γ _total of 11 [mJ / m ² ] <γ _total <15 [mJ / m ² ], but 11.5 [mJ / m ² ] < It is preferable that γ _total <14.5 [mJ / m ² ], and more preferably 12 [mJ / m ² ] <γ _total <14 [mJ / m ² ]. The release agent layer 12 may have a dispersion component γ _b of 8 [mJ / m ² ] <γ _b <11 [mJ / m ² ], but 8.5 [mJ / m ² ] <γ _b. <10.5 [mJ / m ² ] is preferable, and 9 [mJ / m ² ] <γ _b <10 [mJ / m ² ] is more preferable. Thereby, the effect mentioned above can be exhibited more notably. Thereby, the effect mentioned above can be exhibited more notably.

In the release agent layer 12, the polar component γ _p of the surface free energy γ _total is preferably 0.5 [mJ / m ² ] <γ _p <5 [mJ / m ² ]. mJ / m ² ] <γ _p <4.5 [mJ / m ² ] is more preferable, and 1.5 [mJ / m ² ] <γ _p <4 [mJ / m ² ] is further satisfied. preferable. When the polar component γ _p is less than the lower limit value, the composition for forming the release agent layer is easily transferred to the back surface 112 of the release film 10. May occur. When the polar component γ _p exceeds the upper limit, the release agent layer 12 is more closely attached to the pressure-sensitive adhesive layer, and the pressure-sensitive adhesive layer is applied to the adherend with a sticking device such as a labeling machine. If this is done, the machine margin may not be met and a peeling failure may occur.

  Moreover, it is preferable that the peeling film 10 is a light peeling type. When the release film 10 is used as a light release type, the release force P of the release film 10 to the adhesive layer is preferably 10 [mN / 25 mm] <P <50 [mN / 25 mm], and 15 [mN / 25 mm] <P <45 [mN / 25 mm], more preferably 18 [mN / 25 mm] <P <40 [mN / 25 mm].

  The peeling force P of the release film 10 is obtained by laminating the pressure-sensitive adhesive layer on the release film and peeling the pressure-sensitive adhesive layer in accordance with the 180 ° peel test specified in JIS-Z0237.

  When the peeling force P is within the above range, the release film 10 can be favorably peeled from the pressure-sensitive adhesive layer when the release film 10 is peeled from the pressure-sensitive adhesive layer. On the other hand, if the peeling force P is less than the lower limit value, there is a possibility that floating peeling occurs at the interface with the pressure-sensitive adhesive layer. Moreover, when the peeling force P exceeds the said upper limit, peeling defect may generate | occur | produce by the sticking operation by a sticking apparatus.

  The peel strength P of the release film 10 is based on the 180 ° peel test specified in JIS-Z0237, and the adhesive layer is cut to a width of 25 mm and a length of 200 mm and laminated on the release film 10 to form an adhesive. After fixing the layer side to the fixing plate, using a tensile tester, the release film 10 is pulled in the 180 ° direction at a speed of 300 mm / min, and the force required for the release film 10 to peel from the pressure-sensitive adhesive layer. say. As the pressure-sensitive adhesive layer used for the measurement, those described in Examples described later are preferably used.

  In addition, the thickness of the release agent layer 12 is preferably 0.01 μm or more and 5 μm or less, and more preferably 0.03 μm or more and 3 μm or less.

  The surface 121 of the release agent layer 12 (the surface in contact with the adhesive layer of the release film 10) 121 preferably has an arithmetic average roughness Ra of 5 to 50 nm, and more preferably 10 to 40 nm. Further, the maximum protrusion height Rp of the surface 121 of the release agent layer 12 is preferably 50 to 800 nm, and more preferably 100 to 400 nm. When the surface 121 of the release agent layer 12 is in such a surface state, the surface shape of the adhesive surface of the adhesive layer formed on the release agent layer 12 can be improved. Further, it is possible to more effectively prevent charging when the wound release film is fed out.

<Method for producing release film 10>
Next, a method for producing the release film 10 shown in FIG. 1 will be described.

  The release agent layer 12 can be formed by coating (applying) the release agent layer forming composition on the surface 111 of the substrate 11 and drying.

  In this formation, examples of the coating method (coating method) for applying the release agent layer forming composition to the surface 111 of the substrate 11 include a gravure coating method, a bar coating method, a spray coating method, a spin coating method, Air knife coating method, roll coating method, blade coating method, gate roll coating method, die coating method and the like can be mentioned, among which gravure coating method and bar coating method are preferable, and bar coating method is more preferable. . Thereby, the release agent layer 12 having a target thickness can be easily obtained.

  The drying temperature is not particularly limited, but is preferably 100 ° C. or more and 150 ° C. or less, and the drying time is preferably 10 seconds or more and 1 minute or less.

<< Second Embodiment >>
A second embodiment of the pressure-sensitive adhesive body of the present invention will be described.

  FIG. 2 is a cross-sectional view showing a second embodiment of the pressure-sensitive adhesive body according to the present invention. In the following description, the upper side in FIG. 2 is referred to as “upper” and the lower side is referred to as “lower”.

  Hereinafter, the second embodiment of the present invention will be described with reference to this figure, but the description will focus on differences from the above-described embodiment, and the description of the same matters will be omitted.

<Adhesive>
The pressure-sensitive adhesive body 1 shown in FIG. 2 includes a pressure-sensitive adhesive layer 20 having a first pressure-sensitive adhesive surface 201a and a second pressure-sensitive adhesive surface 201b, a first release film 10a attached to the first pressure-sensitive adhesive surface 201a, It has the 2nd peeling film 10b stuck on the 2nd adhesion surface 201b.

  The 1st peeling film 10a is comprised with the peeling film of this invention. The 2nd peeling film 10b is comprised so that peeling force may become relatively larger than the 1st peeling film 10a. That is, the first release film 10a having a relatively large release force is a heavy release agent layer, and the second release film 10b having a relatively low release force is a light release agent layer.

  The pressure-sensitive adhesive body 1 can be used for bonding two adherends (not shown). Specifically, first, the first release film 10a is peeled from the pressure-sensitive adhesive layer 20, and the exposed first pressure-sensitive adhesive surface 201a of the pressure-sensitive adhesive layer 20 is attached to one adherend. Then, the 2nd peeling film 10b is peeled from the adhesive layer 20, and the other to-be-adhered body is stuck on the exposed 2nd adhesion surface 201b. In this way, the two adherends are bonded via the pressure-sensitive adhesive layer 20.

  Hereinafter, the 1st peeling film 10a, the adhesive layer 20, and the 2nd peeling film 10b which comprise the adhesive body 1 concerning this embodiment are demonstrated in detail.

<First release film 10a>
The 1st peeling film 10a shown in FIG. 2 can use the thing similar to the peeling film 10 concerning the said 1st Embodiment, and the peeling containing a peeling agent similarly to the peeling film 10 of 1st Embodiment. It is comprised with the composition for agent layer formation. Moreover, it is preferable that the 1st peeling film 10a shown in FIG. 2 satisfies the same conditions as described in the peeling film 10 of 1st Embodiment also about surface free energy. Thereby, also by the 1st peeling film 10a shown in FIG. 2, the effect | action and effect similar to the peeling film 10 shown in FIG. 1 are produced, and the 1st of the adhesive layer 20 formed on the surface (surface) 121a is produced. It is possible to suppress the generation of crushed skin on the adhesive surface 201a (second adhesive surface 201b).

<Adhesive layer 20>
The pressure-sensitive adhesive layer 20 shown in FIG. 2 is formed using a pressure-sensitive adhesive. In addition, as a form of an adhesive, a solvent type and an emulsion type thing are mentioned.

  The pressure-sensitive adhesive is not particularly limited, and examples thereof include an acrylic pressure-sensitive adhesive, a polyester-based pressure-sensitive adhesive, and a urethane-based pressure-sensitive adhesive. Among these, it is preferable to include an acrylic pressure-sensitive adhesive, and (meth) acrylic. It is preferable that an acid ester copolymer is included. The acrylic ester copolymer has particularly high transparency. Therefore, the pressure-sensitive adhesive layer 20 formed using an acrylic ester copolymer can be particularly suitably used as an optical component application. Moreover, since such an acrylic adhesive normally does not have an unsaturated bond in a molecule | numerator, it can aim at the stability improvement with respect to light or oxygen. The acrylic ester copolymer is also excellent in adhesion durability.

  When the pressure-sensitive adhesive is an acrylic pressure-sensitive adhesive, the pressure-sensitive adhesive is composed of a main monomer component that provides adhesiveness, a comonomer component that provides adhesiveness and cohesive force, and a functional group-containing monomer component that improves crosslinking point and adhesion. It can comprise from the polymer or copolymer which has as a main. By including these components, the cohesive strength and adhesive strength of the obtained pressure-sensitive adhesive layer 20 are improved.

  The main monomer component includes, for example, alkyl groups such as butyl acrylate, amyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, cyclohexyl acrylate, benzyl acrylate, methoxyethyl acrylate and the like having 1 to 20 carbon atoms. Examples include alkyl acrylates and alkyl methacrylates having 1 to 20 carbon atoms in the alkyl group such as butyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, and benzyl methacrylate.

  Examples of the comonomer component include methyl acrylate, methyl methacrylate, ethyl methacrylate, vinyl acetate, styrene, acrylonitrile, and the like.

  The functional group-containing monomer component preferably contains at least one of a hydroxyl group, a carboxyl group, and an amino group as the functional group. Specific examples include 2-hydroxyethyl (meth) acrylate, 2-methacrylic acid 2- Hydroxy (meth) acrylates such as hydroxypropyl, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate (Meth) acrylic acid monomethylaminoethyl, (meth) acrylic acid monoethylaminoethyl, (meth) acrylic acid monomethylaminopropyl, (meth) acrylic acid monoethylaminopropyl, etc. Alkyl; acrylic acid, methacrylate Acid, crotonic acid, maleic acid, itaconic acid, ethylenically unsaturated carboxylic acids such as citraconic acid.

  The (meth) acrylic acid ester copolymer is not particularly limited as to its copolymerization form, and may be any of random, block, and graft copolymers.

  Moreover, as a (meth) acrylic-ester type copolymer, it is preferable to use the thing whose mass mean molecular weight is 500,000 or more, It is more preferable to use what is 600,000-2 million, 700,000-180 It is more preferable to use one of many. Thereby, the adhesiveness and adhesion durability with respect to an adherend are sufficient, and the occurrence of floating and peeling can be more effectively prevented.

  In the present specification, the mass average molecular weight is a value in terms of polystyrene measured by a gel permeation chromatography (GPC) method.

  In this (meth) acrylic acid ester copolymer, the content of units derived from the functional group-containing monomer component is preferably 0.01% by mass or more and 10% by mass or less, and 0.05% by mass or more and 7% by mass or more. It is more preferably 0.0% by mass or less, and further preferably 0.2% by mass or more and 6.0% by mass or less. When the content is within the above range, crosslinking is sufficient by reaction with a crosslinking agent described later. As a result, the pressure-sensitive adhesive layer 20 becomes more excellent in flexibility and adhesion durability.

  In addition, 1 type may be used for such a (meth) acrylic acid ester-type copolymer, and it may use it in combination of 2 or more type.

  Moreover, the adhesive which has the quality and characteristic according to a use can be obtained by selecting the constituent material mentioned above suitably.

  Moreover, the adhesive layer 20 can be formed using the composition for adhesive layer formation which dissolved the adhesive in the organic solvent.

  Examples of the organic solvent used for preparing the pressure-sensitive adhesive layer forming composition include toluene, xylene, t-butanol, acetone, methyl ethyl ketone, tetrahydrofuran, and ethyl acetate.

  The pressure-sensitive adhesive layer forming composition may be either a crosslinked type that undergoes a crosslinking treatment or a non-crosslinked type that does not undergo a crosslinking treatment, but is preferably a crosslinked type. In the case of the composition for forming a cross-linked pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer 20 having better cohesive strength can be formed.

  Examples of the crosslinking agent used in the crosslinkable pressure-sensitive adhesive layer forming composition include isocyanate compounds, epoxy compounds, metal chelate compounds, metal alkoxides, metal salts, amine compounds, hydrazine compounds, and aldehyde compounds.

  The concentration of the pressure-sensitive adhesive layer forming composition is adjusted so that the solid content is in the range of about 5 to 60% by mass using the organic solvent as described above for convenience of coating. In particular, when a low-concentration pressure-sensitive adhesive layer-forming composition having a solid content concentration of 30% by mass or less is used, in the conventional technology, when the pressure-sensitive adhesive layer-forming composition is applied to a release film, it is easy to generate a bruise skin. . However, even if it is a low concentration adhesive layer forming composition, if the peeling film of this invention is applied, generation | occurrence | production of a dirty skin will be suppressed, and it is preferable.

  Moreover, the average thickness of the pressure-sensitive adhesive layer 20 is preferably 1 μm or more and 30 μm or less, and more preferably 2 μm or more and 10 μm or less. When a pressure-sensitive adhesive layer is thinly provided on a release film according to the prior art, it is easy to generate a crusty skin, but even if the composition for forming a pressure-sensitive adhesive layer is thinly applied to the release film of the present invention, a crusty skin is hardly generated. Thereby, the adhesive body 1 of this embodiment is suitable as a joining member for assembling light, thin and small articles, and can contribute to thinning of electronic parts and optical members.

  Further, the proportion of the unevenness outside the range of ± 0.2 μm from the reference surface in the first adhesive surface 201a of the adhesive layer 20 (the surface in contact with the first release film 10a of the adhesive layer 20) is 20%. It is preferable that: For this reason, when sticking the adhesive layer 20 to a to-be-adhered body, it can prevent more effectively that external appearance defect generate | occur | produces. Moreover, the generation | occurrence | production of the bubble in the interface of a to-be-adhered body and the adhesive layer 20 can be reduced as the ratio for which an unevenness | corrugation accounts is in the said range. Therefore, it is possible to further suppress an unintentional decrease in the adhesive strength of the pressure-sensitive adhesive layer 20.

  Note that the ratio of the unevenness outside the range of ± 0.2 μm from the reference surface of the first adhesive surface 201a can be calculated using, for example, an optical interference surface shape observation apparatus. Specifically, using an optical interference type surface shape observation device, stitching is performed at 2.5 magnifications in the VSI mode, and ± 0 from the reference plane is obtained based on the obtained surface shape image in the range of 4 × 4 mm. The image is binarized with a portion outside the range of 2 μm and a portion within the range of ± 0.2 μm. Thereby, it can obtain by calculating the area ratio which the unevenness | corrugation of the part outside the range of +/- 0.2micrometer from a reference plane calculates.

<Second release film 10b>
Next, the 2nd peeling film 10b is demonstrated.

  The 2nd peeling film 10b can be obtained using the composition for release agent layer forming containing a release agent similarly to the 1st release film 10a mentioned above. The characteristic value of the second release film 10b may be in the same range as the first release film 10a or may be included in a different range. However, the material is appropriately selected so that the peel strength of the second release film 10b with respect to the pressure-sensitive adhesive layer is higher than the peel strength of the first release film 10a with respect to the pressure-sensitive adhesive layer.

  Moreover, it is preferable that the peeling force of the 2nd peeling film 10b with respect to an adhesive layer is 30 [mN / 25mm] <P <100 [mN / 25mm], 40 [mN / 25mm] <P <80 [mN. / 25 mm] is more preferable. If the peeling force of the second release film 10b is within the above range, the second release film 10b can be prevented from being unintentionally peeled off when the first release film 10a is peeled off. The release film 10a can be smoothly peeled off.

<Method for Producing Adhesive 1>
Next, a method for manufacturing the pressure-sensitive adhesive body 1 shown in FIG. 2 will be described.

  First, a solvent or the like is added to the above-mentioned pressure-sensitive adhesive to prepare a viscosity suitable for coating (coating) to prepare a pressure-sensitive adhesive layer forming composition.

  Next, on the surface 121a (or the surface 121 (surface) b of the second release film 10b) of the first release film 10a manufactured by the method described in the first embodiment, an adhesive For example, a bar coating method, a reverse roll coating method, a knife coating method, a roll knife coating method, a gravure coating method, so that the film thickness after drying the layer forming composition is about 1 to 30 μm, preferably 2 to 10 μm. The pressure-sensitive adhesive layer 20 is prepared by coating with a conventionally known coating method (coating method) such as an air doctor coating method or a doctor blade coating method, followed by heat drying to thermally crosslink the pressure-sensitive adhesive layer forming composition. To do. The drying temperature is not particularly limited, but is preferably 100 ° C. or more and 150 ° C. or less, and the drying time is preferably 10 seconds or more and 1 minute or less.

  Next, the surface 121b of the second release film 10b manufactured by the same method as that of the first release film 10a (or the surface 121a of the first release film 10a) may be used as the second adhesive layer 20. The adhesive body 1 is obtained by bonding to the adhesive surface 201b.

  According to the second embodiment having the above-described configuration, the same effects as those of the first embodiment described above can be obtained. In other words, it is possible to suppress the generation of crushed skin on the first pressure-sensitive adhesive surface 201a of the pressure-sensitive adhesive layer 20 provided on the first peelable film 10a constituted by the peelable film of the present invention.

«Third embodiment»
A third embodiment of the pressure-sensitive adhesive body of the present invention will be described.

  FIG. 3 is a cross-sectional view showing a third embodiment of the pressure-sensitive adhesive body according to the present invention. In the following description, the upper side in FIG. 3 is referred to as “upper” and the lower side is referred to as “lower”.

  Hereinafter, the third embodiment of the present invention will be described with reference to this drawing, but the description will focus on the differences from the above-described embodiment, and the description of the same matters will be omitted.

<Adhesive>
As shown in FIG. 3, the pressure-sensitive adhesive body 1 according to the present embodiment includes a pressure-sensitive adhesive film 2 having a first pressure-sensitive adhesive surface 201 a and a second pressure-sensitive adhesive surface 201 b, and a first bonded to the first pressure-sensitive adhesive surface 201 a. And a second release film 10b adhered to the second adhesive surface 201b.

  The adhesive film 2 is provided on the core material 21, the first surface 211 a of the core material 21, the first adhesive layer 20 a, and the second adhesive material provided on the second surface 211 b of the core material 21. Agent layer 20b. The surface opposite to the core material 21 of the first pressure-sensitive adhesive layer 20a is the first pressure-sensitive adhesive surface 201a, and the surface opposite to the core material 21 of the second pressure-sensitive adhesive layer 20b is the second pressure-sensitive adhesive surface 201b.

  As in the second embodiment, the first release film 10a is a light release agent layer composed of the release film of the present invention, and the second release film 10b is a heavy release agent layer.

<First release film 10a>
The 1st peeling film 10a shown in FIG. 3 can use the thing similar to the peeling film 10 concerning the said 1st Embodiment, and the peeling containing a peeling agent similarly to the peeling film 10 of 1st Embodiment. It is comprised with the composition for agent layer formation. Further, the first release film 10a shown in FIG. 3 satisfies the same conditions as described for the release film 10 of the first embodiment with respect to surface free energy and the like. Thereby, also by the 1st peeling film 10a shown in FIG. 3, the same effect | action and effect as the peeling film 10 shown in FIG. 1 are produced, and the 1st adhesion surface 201a of the adhesive layer 20 formed on the surface 121a is produced. It is possible to suppress the generation of yuzu skin.

<Adhesive film 2>
(First adhesive layer 20a)
The 1st adhesive layer 20a can use the thing similar to the adhesive layer 20 concerning the said 2nd Embodiment, and the adhesive containing an adhesive similarly to the adhesive layer 20 of 2nd Embodiment. It can be comprised with the composition for layer formation.

(Core 21)
Although there is no restriction | limiting in particular as the core material 21, A plastic film etc. can be used. Examples of the plastic film include polyester films such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene film, polypropylene film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, and ethylene-vinyl acetate copolymer film. , Polystyrene film, polycarbonate film, polymethylpentene film, polysulfone film, polyetheretherketone film, polyethersulfone film, polyphenylene sulfide film, polyetherimide film, polyimide film, fluororesin film, polyamide film, acrylic resin film, norbornene Resin film, cycloolefin tree An oil film etc. are mentioned.

  Among these, it is preferable to use an inexpensive and highly transparent polyethylene terephthalate film. In applications where heat resistance is required, it is preferable to use a polyethylene naphthalate film having a high glass transition point (Tg).

  In addition, the core material 21 made of these plastic films has a first surface 211a and a second one as desired for the purpose of improving the adhesion with the first pressure-sensitive adhesive layer 20a and the second pressure-sensitive adhesive layer 20b. The surface 211b of the second surface can be subjected to a surface treatment or a primer treatment by an oxidation method, an unevenness method, or the like.

  Examples of the oxidation method include corona discharge treatment, plasma discharge treatment, chromic acid treatment (wet), flame treatment, hot air treatment, and ozone / ultraviolet irradiation treatment.

Examples of the unevenness method include a sand blast method and a solvent treatment method.
These surface treatment methods are appropriately selected according to the type of the plastic film and the like, but in general, the corona discharge treatment method is preferably used from the viewpoints of effects and operability.

(Second adhesive layer 20b)
The 2nd adhesive layer 20b can use the thing similar to the adhesive layer 20 concerning the said 2nd Embodiment, and the adhesive containing an adhesive similarly to the adhesive layer 20 of 2nd Embodiment. It can be comprised with the composition for layer formation.

  Note that the first pressure-sensitive adhesive layer 20a and the second pressure-sensitive adhesive layer 20b may be made of different materials, or may be made of the same or the same kind of material.

<Second release film 10b>
The 2nd peeling film 10b can use the thing similar to the 2nd peeling film 10b with which the adhesion body 1 concerning the said 2nd Embodiment is provided.

<Method for Producing Adhesive 1>
Next, a method for manufacturing the pressure-sensitive adhesive body 1 shown in FIG. 3 will be described.

  First, a solvent is added to the above-mentioned pressure-sensitive adhesive as necessary to prepare a viscosity suitable for coating (coating), thereby preparing a pressure-sensitive adhesive layer forming composition.

  Next, the pressure-sensitive adhesive layer forming composition on the surface 121a of the first release film 10a manufactured by the method described in the first embodiment (or the surface 121b of the second release film 10b). The product is coated by a conventionally known coating method (coating method) as described in the second embodiment so that the film thickness after drying is about 1 to 30 μm, preferably 2 to 10 μm, and dried by heating. Then, the pressure-sensitive adhesive layer forming composition is thermally cross-linked to produce the first pressure-sensitive adhesive layer 20a. The drying temperature is not particularly limited, but is preferably 100 ° C. or more and 150 ° C. or less, and the drying time is preferably 10 seconds or more and 1 minute or less. Next, the first pressure-sensitive adhesive layer 20 a is bonded to the surface 211 a of the core material 21.

  Next, a composition for forming an adhesive layer on the surface 121b (or the surface 121a of the first release film 10a) of the second release film 10b produced by the same method as the first release film 10a. The second pressure-sensitive adhesive layer 20b is prepared by coating, heating and drying in the same manner as described above so that the film thickness after drying is about 1 to 30 μm, preferably 2 to 10 μm. And the adhesive body 1 shown in FIG. 3 is obtained by bonding the 2nd adhesive layer 20b to the surface 211b of the core material 21. As shown in FIG.

  According to the third embodiment having the above-described configuration, the same effect as that of the above-described embodiment can be obtained. In other words, it is possible to suppress the generation of crushed skin on the first pressure-sensitive adhesive surface 201a of the pressure-sensitive adhesive layer 20 provided on the first peelable film 10a constituted by the peelable film of the present invention.

<< Fourth Embodiment >>
A fourth embodiment of the pressure-sensitive adhesive body of the present invention will be described.

  FIG. 4 is a cross-sectional view showing a fourth embodiment of the pressure-sensitive adhesive body according to the present invention. In the following description, the upper side in FIG. 4 is referred to as “upper” or “table”, and the lower side is referred to as “lower”.

  Hereinafter, the fourth embodiment of the present invention will be described with reference to this figure, but the description will focus on differences from the above-described embodiment, and the description of the same matters will be omitted.

<Adhesive>
As shown in FIG. 4, the pressure-sensitive adhesive body 1 according to this embodiment includes a pressure-sensitive adhesive film 2 </ b> A having a pressure-sensitive adhesive surface 201 </ b> A and a release film 10 attached to the pressure-sensitive adhesive surface 201 </ b> A.

  The pressure-sensitive adhesive film 2A has a pressure-sensitive adhesive substrate 21A having a surface 211A and a surface (surface) 212A, and a pressure-sensitive adhesive layer 20A provided on the surface 211A of the pressure-sensitive adhesive substrate 21A. The surface of the adhesive layer 20A opposite to the adhesive substrate 21A is an adhesive surface 201A.

<Peeling film 10>
The release film 10 shown in FIG. 4 can use the same thing as the release film 10 concerning the said 1st Embodiment, and the release agent layer containing a release agent similarly to the release film 10 concerning 1st Embodiment. It is comprised with the composition for formation. Moreover, it is preferable that the release film 10 shown in FIG. 4 satisfies the same conditions as described for the release film 10 of the first embodiment with respect to surface free energy and the like. Thereby, also by the peeling film 10 shown in FIG. 4, the same effect | action and effect as the peeling film 10 shown in FIG. 1 are produced, and the skin is generated on the adhesive surface 201A of the adhesive film 2A formed on the surface 121. Can be suppressed.

<Adhesive film 2A>
(Adhesive layer 20A)
The pressure-sensitive adhesive layer 20 </ b> A shown in FIG. 4 can be the same as the pressure-sensitive adhesive layer 20 according to the second embodiment, and as with the pressure-sensitive adhesive layer 20 described above, a pressure-sensitive adhesive layer is formed. It can be comprised with the composition for use.

(Adhesive substrate 21A)
The adhesive substrate 21A shown in FIG. 4 can use the same material as the core material 21 according to the third embodiment.

<Method for Producing Adhesive 1>
Next, a method for manufacturing the pressure-sensitive adhesive body 1 shown in FIG. 4 will be described.

  First, a solvent is added to the above-mentioned pressure-sensitive adhesive as necessary to prepare a viscosity suitable for coating (coating), thereby preparing a pressure-sensitive adhesive layer forming composition.

  Next, on the surface 121 of the release film 10 manufactured by the method described in the first embodiment, the film thickness after drying the pressure-sensitive adhesive layer forming composition is about 1 to 30 μm, preferably 2 to 10 μm. In addition, coating is carried out by a conventionally known coating method (coating method) as described in the second embodiment, followed by heat drying to thermally crosslink the pressure-sensitive adhesive layer forming composition, thereby producing a pressure-sensitive adhesive layer 20A. To do. The drying temperature is not particularly limited, but is preferably 100 ° C. or more and 150 ° C. or less, and the drying time is preferably 10 seconds or more and 1 minute or less. And the adhesive base material 21A is bonded to the adhesive layer 20A, and the adhesive body 1 shown in FIG. 4 is produced.

  Also according to the fourth embodiment having the above-described configuration, the same effects as those of the above-described embodiment can be obtained. That is, it is possible to suppress the generation of scum skin on the adhesive surface 201 of the adhesive film 2A provided on the release film 10 constituted by the release film of the present invention.

  As mentioned above, although this invention was demonstrated in detail based on preferred embodiment, this invention is not limited to this.

  The pressure-sensitive adhesive body of the present invention is not limited to the pressure-sensitive adhesive body of the second to fourth embodiments, and any manufacturing method can be used as long as the pressure-sensitive adhesive layer is attached to the release agent layer included in the release film of the first embodiment. In the process, it is possible to exert an effect that it is difficult to generate scum skin on the adhesive surface.

  Moreover, in 2nd, 3rd embodiment, although the difference was provided in the peeling force of two peeling films, there may be no difference in the peeling force of two peeling films.

  The application of the pressure-sensitive adhesive body of the present invention is not limited to the above-described electronic / optical apparatus. The adhesive body of the present invention is, for example, packaging / bundling, office / household, bonding, coating masking, surface protection, sealing, anticorrosion / waterproofing, electrical insulation, optical equipment, medical / hygiene materials It may be used for any purpose such as for use, display / marking, decoration, and labeling.

Next, specific examples of the release film and the pressure-sensitive adhesive body of the present invention will be described.
[1] Production of adhesive body (Example 1)
1. Preparation of release agent layer forming composition DMS-V52 (manufactured by Gelest, viscosity: 165,000 mPa · s, molecular weight: 155,000, vinyl group content: 0. 0), which is an organopolysiloxane having vinyl groups at both ends. 03 wt%) 10 parts by mass, VDT-163 (vist made by Gelest, viscosity: 3,000,000 mPa · s, vinyl group content: 0.5 mole%), an organopolysiloxane with vinyl groups, 20 parts by mass, organohydro Genopolysiloxane HMS-991 (manufactured by Gelest, viscosity: 22 mPa · s, hydrosilyl group content: 1.67 mole%) was diluted with toluene solvent to a solid content concentration of 1.0 mass%. The mixture was diluted and mixed. 2 parts by mass of a platinum-based catalyst (trade name “PL-50T” manufactured by Shin-Etsu Chemical Co., Ltd., solid content: 2% by mass) was added to this solution to prepare a release agent layer forming composition.

2. Production of Release Film A polyethylene terephthalate (PET) film (thickness 38 μm, arithmetic average roughness Ra: 23 nm, maximum protrusion height Rp: 194 nm) having the same front and back roughness was prepared as a base film.

  Next, on one surface of this substrate, the release agent layer forming composition obtained in the above step was applied with a bar coater so that the thickness after drying was 0.1 μm, and at 120 ° C. It was dried for 1 minute to form a release agent layer on one surface of the substrate. This obtained the peeling film.

3. Preparation of composition for forming pressure-sensitive adhesive layer In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping device, and a nitrogen introduction tube, 79 parts by mass of n-butyl acrylate (BA) and methyl acrylate (MA) 20 1 part by mass, 1 part by mass of 2-hydroxyethyl acrylate (HEA), 200 parts by mass of ethyl acetate, and 0.18 part by mass of 2,2′-azobisisobutyronitrile are charged, and the air in the reaction vessel is nitrogen Replaced with gas. While stirring in this nitrogen atmosphere, the reaction solution was heated to 60 ° C., reacted for 16 hours, and then cooled to room temperature. Here, a part of the obtained solution was subjected to GPC measurement, and production of a (meth) acrylic acid ester polymer having a weight average molecular weight (Mw) of 600,000 was confirmed. Trimethylolpropane-modified tolylene diisocyanate (manufactured by Nippon Polyurethane Co., Ltd., Coronate L) 0.15 as the obtained (meth) acrylic acid ester polymer 100 parts by mass (solid value conversion value) and a crosslinking agent (isocyanate-based crosslinking agent). The composition for forming an adhesive layer having a nonvolatile component concentration of 15% by mass and a viscosity of 100 mPa · s was obtained by mixing with parts by mass, sufficiently stirring, and diluting with methyl ethyl ketone.

  The mass average molecular weight is a value in terms of polystyrene measured by a gel permeation chromatography (GPC) method.

4). Preparation of adhesive body On the release agent layer of the release film, the composition for forming the adhesive layer was applied with a bar coater so that the film thickness after drying was 2 μm, dried at 100 ° C. for 1 minute, and on the release film An adhesive layer (adhesive film) was formed on the substrate. Subsequently, a polyethylene terephthalate film having a thickness of 50 μm was laminated on the pressure-sensitive adhesive layer, thereby obtaining a pressure-sensitive adhesive body.

(Example 2)
A release film and an adhesive were prepared in the same manner as in Example 1 except that the release agent layer forming composition prepared as follows was used.

  30 parts by mass of DMS-V52 (manufactured by Gelest, viscosity: 165,000 mPa · s, molecular weight: 155,000, vinyl group content: 0.03 wt%), an organopolysiloxane having vinyl groups at both ends, organo HMS-991 (manufactured by Gelest, viscosity: 22 cSt, hydrosilyl group content: 1.67 mole%), 1.5 parts by weight, which is a hydrogen polysiloxane, was diluted with a toluene solvent to obtain a solid content concentration of 1.0% by weight. The mixture was diluted and mixed. 2 parts by mass of a platinum-based catalyst (trade name “PL-50T” manufactured by Shin-Etsu Chemical Co., Ltd., solid content: 2% by mass) was added to this solution to prepare a release agent layer forming composition.

(Comparative Example 1)
A release film and an adhesive were prepared in the same manner as in Example 1 except that the release agent layer forming composition prepared as follows was used.

  Shin-Etsu Chemical Co., Ltd., which is an addition reaction type silicone resin release agent: 100 parts by mass of KS-847H (non-volatile content 30%), and DMS-T12 (manufactured by Gelest, viscosity: 20 mPa · s) 10 parts by mass of silicone oil. Were diluted with a toluene solvent and diluted so that the solid content concentration was 1.0% by mass. 2 parts by mass of a platinum-based catalyst (trade name “PL-50T” manufactured by Shin-Etsu Chemical Co., Ltd., solid content: 2% by mass) was added to this solution to prepare a release agent layer forming composition.

(Comparative Example 2)
A release film and an adhesive were prepared in the same manner as in Example 1 except that the release agent layer forming composition prepared as follows was used.

  Arakawa Chemical Industry Co., Ltd .: Silicolite 7412 (non-volatile content 30%), which is an addition reaction type silicone resin release agent, was diluted with a toluene solvent and diluted to a solid content concentration of 1.0% by mass. 2 parts by mass of a platinum-based catalyst (trade name “PL-50T” manufactured by Shin-Etsu Chemical Co., Ltd., solid content: 2% by mass) was added to this solution to prepare a release agent layer forming composition.

(Comparative Example 3)
A release film and an adhesive were prepared in the same manner as in Example 1 except that the release agent layer forming composition prepared as follows was used.

  Shin-Etsu Chemical Co., Ltd., KS-847H, (non-volatile content 30%), which is an addition reaction type silicone resin release agent, was diluted with a toluene solvent and diluted to a solid content concentration of 1.0% by mass. 2 parts by mass of a platinum-based catalyst (trade name “PL-50T” manufactured by Shin-Etsu Chemical Co., Ltd., solid content: 2% by mass) was added to this solution to prepare a release agent layer forming composition.

[2] Evaluation The following evaluations were performed on the release films and pressure-sensitive adhesive bodies of each Example and each Comparative Example obtained as described above.

[2.1] Peeling force About the peeling film of each Example and each comparative example, peeling force was measured based on JIS-Z0237. Specifically, the adhesive surface of the adhesive sheet cut to a width of 25 mm and a length of 200 mm was laminated on the release agent layer side of the release film, and the adhesive sheet side was fixed to a rigid fixing plate. Next, the force required to peel the release film was measured by pulling the release film at a rate of 300 mm / min. The force [mN / 25 mm] required to peel the release film from this pressure-sensitive adhesive layer was taken as the peel force.

  In addition, as an adhesive sheet used for the measurement of peeling force, the laminated body of a 50-micrometer-thick polyethylene terephthalate film and 22-micrometer-thick acrylic adhesive (Toyochem company make, brand name: BPS5127) was used.

[2.2] Surface free energy In each example and each comparative example, after forming the release film and before adhering the adhesive layer and the release film, the surface free energy γ _total of the release agent layer, and its Each component (dispersion component γ _d , polar component γ _p , hydrogen bond component γ _h ) was calculated.

Specifically, the surface free energy γ _total and each component (dispersion component γ _d , polar component γ _p , hydrogen bond component γ _h ) use water, diiodomethane, and bromonaphthalene as probe liquids with known contact angles. , The contact angle of each probe solution to the release agent layer was measured with a contact angle meter, and from the obtained contact angle, Kitasaki and Hata Method (Kitazaki Noriaki et al., Journal of Japan Adhesion Association, Vol.8, No.3, 1972, pp. 131-141). In addition, as a contact angle meter, the contact angle meter (The Kyowa Interface Science Co., Ltd. make, fully automatic contact angle meter DM-701) was used.

[2.3] Silicone Transfer Amount The amount of silicone transferred to the pressure-sensitive adhesive layer was measured with a fluorescent X-ray (Rigaku desktop wavelength dispersive X-ray fluorescence analyzer Mini-Z).

  About each Example and each comparative example, after forming the adhesion body, the amount of silicon atoms of the adhesion surface was measured using fluorescent X-rays, and this was made into the silicone transfer amount.

[2.4] Evaluation of damaged skin of adhesive layer (visual observation)
The light of the fluorescent lamp was reflected on the surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive body of each example and each comparative example, and an image of the reflected fluorescent lamp was observed. When the image of the fluorescent lamp looks undistorted, the appearance is good (◯), and when it looks distorted, the appearance is poor (X).

[2.5] Evaluation of skin on adhesive layer (numericalization)
About the adhesive body of each Example and each comparative example, the peeling film was removed and the exposed surface of the adhesive layer was made into the reference surface, and the area occupation rate of the unevenness | corrugation outside the range of +/- 0.2 micrometer from the reference surface was measured. If the surface of the pressure-sensitive adhesive layer is smooth, the value is close to 0%. Using an optical interference surface shape observation apparatus “Wyko NT-1100” [manufactured by Veeco Co., Ltd.], stitching was performed at 2.5 magnifications in the VSI mode. From the obtained surface shape image in the range of 4 × 4 mm, the image is binarized with a portion outside the range of ± 0.2 μm from the reference plane and a portion within the range of ± 0.2 μm, and from the reference plane The area ratio occupied by the unevenness in the portion outside the range of ± 0.2 μm was calculated.
These results are shown in Table 1.

As is clear from Table 1, the release films of the examples had small values of the surface free energy dispersion component. Moreover, generation | occurrence | production of the yuzu skin was not seen in the adhesive layer with which the adhesive body of an Example is provided. Moreover, the adhesive body of the Example was excellent in the peelability with respect to the adhesive layer of a peeling film.
On the other hand, satisfactory results were not obtained in the comparative example.

DESCRIPTION OF SYMBOLS 1 ... Adhesive body 2, 2A ... Adhesive film 10 ... Release film 10a ... 1st release film 10b ... 2nd release film 11 ... Base material 111 ... Surface 112 ... Back surface (surface)
12 ... release agent layers 121, 121a, 121b ... surface (surface)
20, 20A ... adhesive layer 201, 201A ... adhesive surface 20a ... first adhesive layer 201a ... first adhesive surface 20b ... second adhesive layer 201b ... second adhesive surface 21 ... core material 211a ... first 1st surface 211b ... 2nd surface 21A ... Adhesive base material 211A ... surface 212A ... surface (surface)

Claims (5)

A release film that is releasably attached to an adhesive layer,
A substrate;
A release agent layer provided on one surface side of the substrate,
The surface free energy γ _total of the release agent layer satisfies the relationship of 11 [mJ / m ² ] <γ _total <15 [mJ / m ² ],
A release film, wherein a dispersion component γ _d of the surface free energy γ _total satisfies a relationship of 8 [mJ / m ² ] <γ _d <11 [mJ / m ² ].   The peel force P of the release agent layer is based on a 180 ° peel test defined in JIS-Z0237, and satisfies a relationship of 10 [mN / 25 mm] <P <50 [mN / 25 mm]. Release film. The release film according to claim 1, wherein a polar component γ _p of the surface free energy γ _total satisfies a relationship of 0.5 [mJ / m ² ] <γ _p <5 [mJ / m ² ]. .   The release film according to any one of claims 1 to 3, wherein the release agent layer does not contain silicone oil as a light release additive. A substrate;
A release agent layer provided on one surface side of the substrate,
The surface free energy γ _total of the release agent layer satisfies the relationship of 11 [mJ / m ² ] <γ _total <15 [mJ / m ² ],
A release film satisfying a relationship in which a dispersion component γ _d of the surface free energy γ _total satisfies a relationship of 8 [mJ / m ² ] <γ _d <11 [mJ / m ² ];
A pressure-sensitive adhesive body comprising: a pressure-sensitive adhesive layer attached to a surface of the release agent layer opposite to the surface on which the substrate is provided.

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