JP6129695B2 - Optical pressure-sensitive adhesive sheet and method for producing the same - Google Patents

Description

  The present invention relates to an optical pressure-sensitive adhesive sheet, particularly to an optical pressure-sensitive adhesive sheet used for bonding optical members and a method for producing the same.

  In recent years, display devices such as a liquid crystal display (LCD) and input devices configured in combination with a display device such as a touch panel have been widely used in various fields. When these display devices and input devices are manufactured, a transparent optical adhesive sheet (adhesive tape) is used for bonding optical members. For example, a liquid crystal display and a protective plate of a touch panel portable terminal are used. Used for pasting. Such a pressure-sensitive adhesive sheet is usually formed into a shape according to the use mode by punching.

  The pressure-sensitive adhesive sheet used for bonding optical members is usually provided with a separator that is peeled off at the time of use of the pressure-sensitive adhesive layer on one surface of the pressure-sensitive adhesive layer, and the pressure-sensitive adhesive on the other surface of the pressure-sensitive adhesive layer. A base material such as a PET film as an adherend of the layer is bonded, and a pressure-sensitive adhesive sheet having a desired shape is obtained by punching using a punching machine from the PET film side serving as the base material (for example, Patent Document 1).

  However, the pressure-sensitive adhesive sheet obtained by the conventional punching process is distorted between the separator and the pressure-sensitive adhesive layer depending on the combination of the base material, the pressure-sensitive adhesive layer, the type of separator, the thickness, and the like. In some cases, it is referred to as “pressure-sensitive adhesive distortion”, which causes a problem of poor punching workability such as deterioration of the quality of the pressure-sensitive adhesive sheet.

JP 2012-62351 A

  The present invention has been made in view of the above-described problems of the prior art, and an object thereof is to provide an optical pressure-sensitive adhesive sheet that can effectively suppress the occurrence of pressure-sensitive adhesive distortion during punching of the optical pressure-sensitive adhesive sheet and a method for producing the same. .

  As a result of intensive studies to solve the above problems, the present inventors once peeled off the first separator attached to the adhesive body from the adhesive body having the first separator on at least one side, and then It has been found that the occurrence of pressure-sensitive adhesive distortion can be effectively suppressed by performing punching after reattaching a new second separator different from the first separator to the pressure-sensitive adhesive body. The present invention has been completed based on this finding.

That is, the gist configuration of the present invention is as follows.
(1) In the method of manufacturing an optical pressure-sensitive adhesive sheet having a predetermined shape by punching an optical pressure-sensitive adhesive body having a first separator on at least one side, the punching is performed by peeling the first separator from the pressure-sensitive adhesive body. Then, the second separator is reattached to the pressure-sensitive adhesive body, and the method is performed in a state where the peeling force between the pressure-sensitive adhesive body and the second separator is low.

  (2) The above (1) is characterized in that the peeling force is at least 10% lower than the peeling force between the pressure-sensitive adhesive body and the first separator, measured at a peeling angle of 0 °. The manufacturing method of the optical adhesive sheet of description.

  (3) An optical pressure-sensitive adhesive sheet produced by the method described in (1) or (2) above.

  (4) The optical pressure-sensitive adhesive sheet according to (3), wherein the optical pressure-sensitive adhesive sheet is disposed between a liquid crystal display and a transparent protective lens.

  According to the present invention, it is possible to provide an optical pressure-sensitive adhesive sheet in which the occurrence of pressure-sensitive adhesive distortion is effectively suppressed by stamping after optimizing the adhesive force between the optical pressure-sensitive adhesive body and the separator. As a result, it is possible to prevent deterioration of the quality of the optical pressure-sensitive adhesive sheet.

It is a disassembled perspective view of the display apparatus which has the touchscreen function manufactured using the optical adhesive sheet according to this invention. It is a perspective view which shows the layer structure of the adhesive body with a separator before punching and manufacturing the optical adhesive sheet used for the display apparatus of FIG. It is a conceptual diagram when adhesive distortion generate | occur | produces in the optical adhesive sheet manufactured by the conventional method. Sample A was used as the pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer, and before and after the first separator adhered to the pressure-sensitive adhesive was replaced with the second separator, the peeling force was changed between two types of peeling speeds (600 mm / min and 1000 mm). / Min) shows the result when measured. Sample B was used as the pressure-sensitive adhesive to form the pressure-sensitive adhesive layer of the pressure-sensitive adhesive body, and before and after the first separator adhered to the pressure-sensitive adhesive body was replaced with the second separator, the peeling force was changed to two types of peeling speeds (600 mm / The result when measured at a minute and 1000 mm / min) is shown.

  Next, a typical optical pressure-sensitive adhesive sheet according to the present invention will be described below with reference to the drawings. In addition, embodiment shown below has illustrated only typical embodiment used in order to demonstrate this invention concretely, and can take various embodiment in the scope of this invention.

  FIG. 1 shows a display device having a touch panel function manufactured using an optical pressure-sensitive adhesive sheet according to the present invention, and FIG. 2 shows a layer structure of a pressure-sensitive adhesive body with a separator.

  A display device 101 having a touch panel function manufactured using the optical adhesive sheet shown in FIG. 1 includes a liquid crystal display 1, an optical adhesive sheet 2, an ITO (Indium Tin Oxide) glass substrate 3, and a transparent adhesive sheet 4. The transparent protective lens 5 is mainly composed.

  The liquid crystal display 1 is provided for displaying an image on the image display unit of the display device 101, and the optical adhesive sheet 2 is provided for bonding the liquid crystal display 1 and the ITO glass substrate 3 together. The ITO glass substrate 3 is provided as a glass substrate having a transparent conductive film. The transparent adhesive sheet 4 is provided for bonding the ITO glass substrate 3 and the transparent protective lens 5, and the material is not particularly limited, and a known transparent adhesive sheet can be used. The transparent protective lens 5 is provided to protect the surface of the display device 101 from dirt and scratches, and the material thereof is not particularly limited, and a known transparent protective lens can be used. it can.

  The optical pressure-sensitive adhesive sheet 2 in FIG. 1 is obtained by punching an adhesive body having a first separator on at least one side, and FIG. 2 shows a pressure-sensitive adhesive with a separator before punching. The body is shown so that the layer structure can be understood. The pressure-sensitive adhesive body 50 is mainly composed of the pressure-sensitive adhesive layer 20, the base material 30, and the protective film 40, and further, the separator 10A or 10B. Is pasted.

  The separator is a member provided as a release sheet for the pressure-sensitive adhesive layer 20, and represents either the first separator 10A or the second separator 10B in the present invention.

  Here, the separator is not particularly limited, and a known separator can be used. For example, polyester resins such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT). The separator which uses the plastic film comprised from this as a base material can be used. Among these, a PET film is preferable from the viewpoint of mechanical strength and the like. Moreover, the separator surface-treated with the well-known peeling processing agent can also be used for the surface of the said separator.

  The thickness of the separator is not particularly limited, but is preferably 25 μm or more and less than 100 μm, more preferably 35 to 50 μm from the viewpoint of enabling the pressure-sensitive adhesive body with the separator to be rolled up. 80 μm.

  The above-mentioned “new second separator different from the first separator” means that the second separator does not include a reuse of the first separator. Specifically, After the first separator 10A is peeled from the adhesive layer 20, when the second separator 10B is reapplied to the adhesive layer 20, the second separator 10B is newly composed of the same material as the first separator 10A. May be a new separator, or a new separator made of a different material.

  The pressure-sensitive adhesive layer 20 constitutes a pressure-sensitive adhesive surface of a pressure-sensitive adhesive body 50 for bonding the liquid crystal display 1 and the ITO glass substrate 3 in FIG.

  Here, the pressure-sensitive adhesive for constituting the pressure-sensitive adhesive layer 20 is not particularly limited. For example, known pressure-sensitive adhesives such as acrylic pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, silicone-based pressure-sensitive adhesives, and urethane-based pressure-sensitive adhesives. The pressure-sensitive adhesive layer can be formed by using pressure-sensitive adhesives alone or in combination of two or more. Among them, the pressure-sensitive adhesive layer is preferably an acrylic pressure-sensitive adhesive layer particularly from the viewpoint of transparency, weather resistance, heat resistance, solvent resistance, and the like.

  Moreover, although the thickness of the adhesive layer 20 is not specifically limited, It is preferable that it is the range of 6-250 micrometers, More preferably, it is the range of 12-175 micrometers. By making the thickness 6 μm or more, the step absorbability can be improved. On the other hand, by making the thickness 250 μm or less, it is advantageous for miniaturization and thinning of optical products and optical members. Furthermore, the punching processability of the optical pressure-sensitive adhesive sheet can be improved by the thin thickness.

  The pressure-sensitive adhesive layer 20 preferably has high transparency from the viewpoint of use for an optical member. For example, in the visible light wavelength region, the total light transmittance is preferably 80% or more, more preferably. Is 85% or more, more preferably 90% or more. Further, the haze of the pressure-sensitive adhesive layer 20 is preferably 3% or less, and more preferably 1.5% or less. The higher the transparency of the pressure-sensitive adhesive layer 20 and the lower the haze, the more the optical pressure-sensitive adhesive sheet that does not hinder the visibility even when bonded to a liquid crystal display, for example, when processed into an optical pressure-sensitive adhesive sheet having a predetermined shape. Can be obtained. The total light transmittance and haze can be measured using, for example, a haze meter (trade name “HM-150” manufactured by Murakami Color Research Laboratory Co., Ltd.), which is a method based on JIS K7361.

  The pressure-sensitive adhesive layer 20 may be a double-sided pressure-sensitive adhesive body in which both surfaces of the pressure-sensitive adhesive layer 20 are adhesive surfaces, or a single-sided pressure-sensitive adhesive body having the first separator 10A only on one surface of the pressure-sensitive adhesive layer 20. May be. When the pressure-sensitive adhesive layer 20 is a double-sided pressure-sensitive adhesive body, it is only necessary to have the first separator 10A on at least one pressure-sensitive adhesive surface of the pressure-sensitive adhesive body, and the other pressure-sensitive adhesive surface does not necessarily have the first separator 10A. It doesn't have to be. Moreover, when it has the 1st separator 10A on both the adhesive surfaces of a double-sided adhesive body, the 1st separator 10A of both surfaces of the adhesive layer 20 may be the same separator, and a different separator may be sufficient as it. Moreover, as one double-sided adhesive body in which one adhesive surface of the double-sided adhesive body does not have the first separator 10A, for example, as shown in FIG. It can be set as the double-sided adhesive body which has the base material 30 in the adhesive surface. In the present invention, from the viewpoint of mechanical strength of the optical pressure-sensitive adhesive sheet 2, in particular, both surfaces as a layer structure having the first separator 10 </ b> A on one pressure-sensitive adhesive surface and the substrate 30 on the other adhesive surface. The use of an adhesive is preferred.

  As described above, the base material 30 can be provided on the pressure-sensitive adhesive layer 20 in order to improve the mechanical strength of the optical pressure-sensitive adhesive sheet 2, but the base material 30 is not necessarily attached to the pressure-sensitive adhesive layer 20. On the other hand, the pressure-sensitive adhesive layer 20 can be applied to the substrate 30.

  Here, the base material 30 is not particularly limited, and a known base material can be used. For example, the base material 30 is based on a plastic film made of a plastic material of a polyester resin such as polyethylene terephthalate (PET). It can be used as the material 30. Among these, a PET film is preferable from the viewpoints of processability, transparency, and adhesiveness to the pressure-sensitive adhesive layer 20.

  Moreover, it is preferable that the base material 30 has high transparency comparable as the adhesive layer 20 from a viewpoint of use to an optical member. Moreover, the thickness of the base material 30 is not particularly limited, but is preferably in the range of 12 to 75 μm from the viewpoint of punching workability of the optical pressure-sensitive adhesive sheet 100.

  Further, when the punching process is performed, in order to protect the base material 30 from dirt and scratches, the surface of the base material 30 opposite to the surface to be bonded to the pressure-sensitive adhesive layer 20 is protected as shown in FIG. A film 40 may be provided.

  The protective film 40 is not specifically limited, A well-known base material can be used, For example, the film similar to each plastic film mentioned for the separator can be used.

  The thickness of the protective film 40 is not particularly limited, but is preferably in the range of 10 to 50 μm, more preferably 15 to 35 μm, from the viewpoint of punching workability of the optical pressure-sensitive adhesive sheet 100.

  The method for producing an optical pressure-sensitive adhesive sheet according to the present invention is to perform punching after optimizing the adhesive force between the pressure-sensitive adhesive body and the separator. More specifically, the punching is performed by the first separator. 10A is peeled from the pressure-sensitive adhesive body 50, and then the second separator 10B different from the first separator 10A is re-attached to the pressure-sensitive adhesive body 50, and the peeling force between the pressure-sensitive adhesive body 50 and the second separator 10B is increased. By adopting this configuration, it becomes possible to provide the optical pressure-sensitive adhesive sheet 2 in which the occurrence of pressure-sensitive adhesive distortion during punching is effectively suppressed, and thereby the optical pressure-sensitive adhesive sheet 2. Can prevent the deterioration of quality.

  Here, as a method for producing the optical pressure-sensitive adhesive sheet 2 according to the present invention, for example, the first separator 10A that has been adhered to the pressure-sensitive adhesive body 50 is once peeled from the pressure-sensitive adhesive layer 20 of the pressure-sensitive adhesive body 50, and then the pressure-sensitive adhesive layer. The optical adhesive sheet 2 having a predetermined shape is manufactured by punching the adhesive body 50 in which the second separator 10B, which is different from the first separator 10A, is pasted on the blade 20 with a blade such as a double blade or a single blade, for example. Can do.

  In addition, the method of attaching the first separator 10A or the second separator 10B to the pressure-sensitive adhesive layer 20 is not particularly limited, and is a continuous method in which a long strip member is connected from roll to roll. Alternatively, it may be a system in which adhesive bodies having a predetermined shape are performed one by one or a system in which the adhesive bodies are cut for each predetermined length.

The peeling force defined in the present invention is a peeling force (N / cm ² ) between the pressure-sensitive adhesive body 50 and the second separator 10B measured at a peeling angle of 0 ° and a predetermined peeling speed, so-called shear stress. means. Here, the state where the peeling force is low means a state where the peeling force is reduced at least before and after the separator is attached to the adhesive body. Specifically, the first separator 10A and the pressure-sensitive adhesive layer 20 are used. Compared to the peeling force between the adhesive body 50 and the pressure-sensitive adhesive body 50 (before re-sticking), the peeling force between the second separator 10 and the pressure-sensitive adhesive body 50 that sandwiches the pressure-sensitive adhesive layer 20 (after re-sticking) is reduced. Means the state. In the present invention, the peeling force between the pressure-sensitive adhesive layer 20 and the second separator 10B can be lowered by the re-sticking process from the first separator 10A to the second separator 10B, whereby the pressure-sensitive adhesive 50 During the punching process, it is possible to effectively suppress the occurrence of adhesive distortion.

  In addition, if the peeling force between the pressure-sensitive adhesive body 50 and the second separator 10B is low by the re-sticking process from the first separator 10A to the second separator 10B, the pressure-sensitive adhesive strain is not affected regardless of the type of the pressure-sensitive adhesive body. Therefore, it is possible to produce an optical pressure-sensitive adhesive sheet that effectively suppresses the occurrence of pressure-sensitive adhesive distortion according to the mode of use.

  The mechanism in which the adhesive distortion occurs between the separator and the adhesive layer 20 is that a large load is applied from the punching side toward the inside of the adhesive body 50 when the adhesive body 50 is punched. Since stress (hereinafter referred to as “punching stress”) is generated inside the body 50, the punched portion of the pressure-sensitive adhesive layer 20 constituting the pressure-sensitive adhesive body 50 is greatly bent and deformed. This is performed in a state where the portion of the pressure-sensitive adhesive body 50 to be punched is pressed from above using a cushion such as rubber for the adhesive. If the pressure-sensitive adhesive layer located between the pressure-sensitive adhesive body 50 and the separator is too strong, When an accompanying stress wave is transmitted when a punching stress is generated in the adhesive layer 20, the stress wave cannot escape from the adhesive layer to the outside and remains in the adhesive layer. As a result, for example, FIG. As shown, is considered an edge portion of the optical pressure-sensitive adhesive sheet 100 punched are derived from that would appear as a stripe-shaped adhesive strain 6.

  That is, in the present invention, the adhesive layer can be substantially floated from the separator by reducing the adhesive force of the adhesive layer located between the adhesive body 50 and the separator by reattaching the separator. Therefore, the deflection of the pressure-sensitive adhesive layer due to punching stress, that is, the deformation of the pressure-sensitive adhesive layer can be reduced. As a result, the accompanying stress wave is also reduced, and the occurrence of pressure-sensitive adhesive distortion is effectively suppressed. I think it can be done.

  In the present invention, the peel force between the pressure-sensitive adhesive body 50 and the second separator 10B measured at a peel angle of 0 ° is at least 10% lower than the peel force between the pressure-sensitive adhesive body 50 and the first separator 10A. It is preferable, and more preferably 20% or more lower, whereby the deformation of the pressure-sensitive adhesive layer can be further relaxed, and as a result, the occurrence of pressure-sensitive adhesive distortion can be more effectively suppressed. On the other hand, when the decrease in the peeling force is larger than 30%, the peeling force between the pressure-sensitive adhesive body 50 and the second separator 10B is too small when the optical pressure-sensitive adhesive sheet is commercialized. Since separator 10B will be easy to peel, it is preferable that it is 30% or less.

  The optical pressure-sensitive adhesive sheet 2 according to the present invention is used particularly for bonding optical members, and is disposed, for example, between the liquid crystal display 1 and the transparent protective lens 5. Thereby, for example, a display device having a touch panel function as shown in FIG. 1 can be manufactured, and in particular, distortion to the view area of the liquid crystal screen is improved and quality is further improved. Further, the display device can be manufactured.

  EXAMPLES Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to the following examples. In addition, manufacture of the adhesive sheet for optics before re-separating a separator was implemented by the well-known method.

The following acrylic pressure-sensitive adhesive composition was used as the pressure-sensitive adhesive constituting the pressure-sensitive adhesive body of the present invention.
[Sample A]
In a reaction vessel equipped with a cooling pipe, a nitrogen introduction pipe, a thermometer and a stirring device, 95 parts by weight of 2-ethylhexyl acrylate (2EHA), 5 parts by weight of acrylic acid (AA), 0.2 parts by weight of benzoyl peroxide, and 100 parts by weight of toluene was added and polymerized at 61 ° C. for 6 hours in a nitrogen stream to obtain an acrylic copolymer A.
Sample A was prepared by adding 3 parts by weight of a polyisocyanate compound (trade name “Coronate L”, manufactured by Nippon Polyurethane Co., Ltd.) to 100 parts by weight of the solid content of the acrylic copolymer A.
[Sample B]
In a reaction vessel equipped with a cooling pipe, a nitrogen introduction pipe, a thermometer and a stirrer, 63 parts by weight of 2-ethylhexyl acrylate (2EHA), 15 parts by weight of N-vinyl-2-pyrrolidone, 9 parts by weight of methyl methacrylate (MMA) Part, 2-hydroxyethyl acrylate (HEA) 13 parts by weight, benzoyl peroxide 0.2 parts by weight, and toluene 100 parts by weight were polymerized in a nitrogen stream at 61 ° C. for 6 hours to obtain an acrylic copolymer. B was obtained.
Sample B was prepared by adding 3 parts by weight of a polyisocyanate compound (trade name “Coronate L”, manufactured by Nippon Polyurethane Co., Ltd.) to 100 parts by weight of the solid content of the acrylic copolymer B.

Example 1
A pressure-sensitive adhesive layer was formed using Sample A on a treated surface of PET (thickness: 50 μm) as a first separator so as to be a double-sided adhesive body having a thickness of about 50 μm. Next, a base material (thickness: 50 μm) is bonded to the adhesive surface of the double-sided adhesive body that does not have the first separator, and a protective film (thickness: 26 μm) is further applied to the base material. Thus, an optical pressure-sensitive adhesive body having a separator was produced. Thereafter, the first separator was peeled off from the pressure-sensitive adhesive body, and subsequently, PET (thickness: 75 μm) was re-attached as a second separator to the release surface of the pressure-sensitive adhesive body.

Example 2
A pressure-sensitive adhesive layer was formed using Sample B on a treated surface of PET (thickness: 50 μm) as a first separator so as to be a double-sided adhesive body having a thickness of about 50 μm. Next, a base material (thickness: 50 μm) is bonded to the adhesive surface of the double-sided adhesive body that does not have the first separator, and a protective film (thickness: 26 μm) is further applied to the base material. Thus, an optical pressure-sensitive adhesive body having a separator was produced. Thereafter, the first separator was peeled off from the pressure-sensitive adhesive body, and subsequently, PET (thickness: 75 μm) was re-attached as a second separator to the release surface of the pressure-sensitive adhesive body.

Comparative Example 1
An optical pressure-sensitive adhesive body having a separator was prepared in the same manner as in Example 1 except that the step of re-attaching the first separator of the pressure-sensitive adhesive body to the second separator was not included.

Comparative Example 2
An optical pressure-sensitive adhesive body having a separator was prepared in the same manner as in Example 2 except that the step of re-attaching the first separator of the pressure-sensitive adhesive body to the second separator was not included.

  Each optical pressure-sensitive adhesive body obtained in Examples and Comparative Examples is punched from the protective film side using a punching machine (WBJ802, manufactured by Yamaoka Seisakusho Co., Ltd.) with a double-edged, single-edged blade at a speed of 20 to 200 spm. To give an optical pressure-sensitive adhesive sheet. At that time, sample cuts having a layer structure as shown in FIG. 2 having a length of 150 mm and a width of 10 mm were obtained for evaluation of punching workability.

  Table 1 shows the results of changes in punching workability and peeling force of these sample cuts. In addition, the evaluation of the punching workability is effective when the punching process is carried out, and the sample cut that has occurred to such an extent that “adhesive distortion” can be visually confirmed cannot be confirmed by “x” and “adhesive distortion” visually. Sample cuts that were suppressed to “◯” were marked with “◯”. Moreover, about peeling force, it measured with the following method. The results are shown in FIG. 4 and FIG.

Measurement of Peeling Force The protective film 40 was peeled from the sample cut having a layer structure as shown in FIG. 2, and then both the base material 30 and the pressure-sensitive adhesive layer 20 were cut from one end to a portion of 70 mm. Next, only the separator 10A or 10B was cut from the other end of the pressure-sensitive adhesive layer 20 to a portion of 70 mm. That is, by such a cut, a three-layer structure of the base material 30 / the pressure-sensitive adhesive layer 20 / the separator 10A or 10B is left in the range of 10 mm × 10 mm only in the center portion of the sample cut, and this portion is measured as a measurement sample. Size. After that, a non-slip portion was created using a masking tape at both ends of the test piece cut in this way, and a tensile tester (manufactured by Tensilon Tansui Co., Ltd.) in an environment of 23 ° C. and 50% (relative humidity). Using a product name “NMB TG-1 kN”), the peel force at a peel angle of 0 ° was measured. At the time of peeling, the film was pulled only from the substrate 30 side, and the peeling speed was measured at both 600 mm / min and 1000 mm / min.

  As shown in Table 1 and FIGS. 4 and 5, the optical pressure-sensitive adhesive sheet (Example) according to the present invention effectively suppresses “pressure-sensitive adhesive distortion” in the punching process. When the 1 separator is not re-applied to the second separator (comparative example), it can be confirmed that “adhesive distortion” has occurred in the punching process, and therefore, by using the method for producing an optical pressure-sensitive adhesive sheet according to the present invention. It is possible to provide an optical pressure-sensitive adhesive sheet manufactured by an excellent punching process in which pressure-sensitive adhesive distortion is effectively suppressed, and as a result, it is possible to prevent deterioration of the quality of the optical pressure-sensitive adhesive sheet. Recognize. Moreover, it turns out that generation | occurrence | production of an adhesive distortion can be suppressed effectively by implementing this invention irrespective of the kind of adhesive used.

  According to the present invention, an optical pressure-sensitive adhesive sheet in which the occurrence of pressure-sensitive adhesive distortion is effectively suppressed by punching after optimizing the adhesive force between the pressure-sensitive adhesive body and the separator in the optical pressure-sensitive adhesive sheet. It became possible to provide, and it became possible to prevent the deterioration of the quality of the optical adhesive sheet.

DESCRIPTION OF SYMBOLS 1 Liquid crystal display 2 Optical adhesive sheet 3 ITO glass substrate 4 Transparent adhesive sheet 5 Transparent protective lens 6 Adhesive distortion 10A 1st separator 10B 2nd separator 20 Adhesive layer 30 Base material 40 Protective film 50 Adhesive body 100 Optical adhesive sheet 101 Display device

Claims (1)

In the method for producing an optical pressure-sensitive adhesive sheet having a predetermined shape by punching an adhesive body having a first separator on at least one side,
In the punching process, after the first separator is peeled from the adhesive body, the second separator is reattached to the adhesive body, and the peeling force between the adhesive body and the second separator is The method for producing an optical pressure-sensitive adhesive sheet, characterized in that the measurement is performed at a peeling angle of 0 ° with respect to the peeling force between the first separator and 10% to 30% lower .