KR102704131B1 - Pattered Adhesive tape, Release film for forming the same and Method of producing Release film - Google Patents

Abstract

The present invention relates to an adhesive tape, a release film forming the same, and a method for manufacturing the release film, and more particularly, to a patterned release film using a UV imprinting method, and an adhesive tape formed therefrom that is also patterned so as to enable implementation of delicate patterning compared to conventional technologies, and to easily remove air bubbles generated during a laminating process of the tape, thereby reducing defects in module and component assembly and simplifying the process to obtain productivity and cost reduction effects, and in particular, to a patterned adhesive tape, a release film forming the same, and a method for manufacturing the release film, which can resolve reliability issues of components caused by problems such as air being trapped during laminating of the tape due to the formation of a fine pattern.

Description

{Patterned adhesive tape, release film for forming the same and method of producing release film}

The present invention relates to a patterned adhesive tape, a release film forming the same, and a method for manufacturing the release film.

With the development of advanced industries, the need for protecting parts and modules from the outside by using tape or joining them with tape instead of screw fixing them is increasing.

In line with the trend toward advanced components and modules, the laminating process is performed using protective tapes and bonding tapes, and the demand for removing air bubbles generated inside the tape is gradually increasing.

For example, when applying PPF film to the exterior of a car or protective tape to a tablet case, there is a problem that if bubbles occur during the laminating process, delaminating and then re-laminating are required.

Among the protective tapes, acrylic adhesive protective tape, silicone adhesive protective tape, and urethane adhesive protective tape are most commonly used.

Among the above tapes, protective tapes using silicone adhesives generate the least amount of bubbles during lamination. However, if the adhesive coating thickness is high or the adhesive strength is high, bubbles tend to increase during lamination, making lamination difficult.

As technological trends lead to advanced components and modules in terms of size and functionality, they are assembled with tape rather than screws or protected with protective tape to maintain their appearance and performance.

For example, most OLED panels are assembled by laminating and bonding them with functional tapes into a single module. Since these OLED modules require high impact resistance, thermal conductivity for heat dissipation, and heat resistance, functional acrylic, urethane, or silicone-based adhesive double-sided tapes are used, and the coating thickness of the adhesive layer is also high, at 30㎛ or more. Therefore, it is very important for product reliability to assemble the functional tape without air bubbles during laminating and bonding.

To this end, domestic registration patent No. 10-0525628, domestic registration patent No. 10-0560341, and domestic publication patent No. 2016-0014765 attempted to introduce a structured surface to an adhesive product to expel air within the tape, but the level of bubble removal fell short of expectations and the process was complex, so there are still problems.

Therefore, in order to suppress bubble generation during laminating, the wettability of the tape must be optimized, but since it is limited by the functional aspect, research on this is urgently needed.

Accordingly, the present invention provides a patterned release film and an adhesive tape formed therefrom using a UV imprinting method, which are patterned so that more delicate patterning can be implemented compared to the prior art, and air bubbles generated during the laminating process of the tape can be easily removed to reduce defects in module and component assembly, and the process can be simplified to obtain productivity and cost reduction effects, and in particular, a patterned adhesive tape, a release film forming the same, and a method for manufacturing the release film, which can resolve reliability problems of components caused by problems such as air being trapped during laminating of the tape due to the formation of a fine pattern.

A preferred embodiment of the present invention for solving the above problem provides an adhesive tape including a base film and an adhesive layer formed on the base film, wherein the adhesive layer includes a pattern having air passages and micro-air passages connected to the air passages formed on a surface thereof, and the pattern having the micro-air passages connected to the air passages formed includes a shape in which the micro-air passages connect a predetermined section of air passages to another predetermined section of air passages.

The pattern in which micro-air passages connected to the above air passages are formed is characterized in that a plurality of micro-air passages are formed by connecting between one side of an air passage and one side of another air passage.

The above air passages and micro-air passages are each characterized by having a concave structure in the shape of a U-shape, a V-shape, a hemisphere, or a square in their cross sections.

The width of the above micro-air passage is characterized by a ratio of 1:1 to 100.

It is characterized in that the depth of the above micro-air passage is in a ratio of 1:1 to 50 to the depth of the air passage.

The above adhesive layer is characterized by including at least one selected from an acrylic adhesive, a silicone adhesive, a rubber-based adhesive, a urethane adhesive, and a modified polyester adhesive.

According to another preferred embodiment of the present invention, a release film is provided, comprising: a base film; a pattern layer formed on the base film; and a release layer formed on the pattern layer, wherein the pattern layer includes a pattern having air passages and micro-air passages connected to the air passages formed on a surface thereof, and the pattern having the micro-air passages connected to the air passages formed includes a shape in which the micro-air passages connect a predetermined section of the air passages to another predetermined section of the air passages.

The pattern in which micro-air passages connected to the above air passages are formed is characterized in that a plurality of micro-air passages are formed by connecting between one side of an air passage and one side of another air passage.

The above air passages and micro-air passages are each characterized by having a convex structure in the shape of a U-shape, a V-shape, a hemisphere, or a square in their cross sections.

The width of the above micro-air passage is characterized by a ratio of 1:1 to 100.

It is characterized in that the depth of the above micro-air passage is in a ratio of 1:1 to 50 to the depth of the air passage.

The above pattern layer is characterized by including at least one selected from a UV-curable acrylate resin, a UV-curable epoxy resin, or an EB-curable vinyl resin.

The above pattern layer is characterized by having a thickness of 3 to 200 μm. Do it.

The above release layer comprises at least one selected from a thermosetting silicone release resin, a fluorine-based silicone release resin, and a non-silicone release resin. It is characterized by having a film thickness of the heterogeneous layer of 0.1 to 2 ㎛.

According to another preferred embodiment of the present invention, a method for manufacturing a release film is provided, including the steps of (S1) forming a pattern layer by coating a UV-curable resin composition on a base film, applying pressure to the upper surface thereof with a mold, and irradiating the substrate with a UV lamp to cure the same, thereby forming a pattern; and (S2) forming a release layer by coating a composition including at least one selected from a thermosetting silicone release resin, a fluorine-based silicone release resin, and a non-silicone release resin on the upper portion of the formed pattern layer.

The process of irradiating the UV/EB lamp in the above step S1 is characterized in that it is performed with a source of 0.1 J/cm2 or more of irradiation amount at a wavelength of UV (ultraviolet ray: light with a wavelength of 200 to 450 nm) or EB (electron beam: wavelength of 10 ^-3 to 10 ¹⁰ nm) for 0.1 second to ¹ minute.

According to one embodiment of the present invention, the adhesive tape, the release film forming the same, and the method for manufacturing the release film use a UV imprinting method to pattern the release film and the adhesive tape formed therefrom, which are also patterned, thereby enabling more delicate patterning than conventional techniques, simplifying the process to obtain productivity and cost-saving effects, and in particular, since a fine pattern is formed, problems such as air being trapped in the adherend when laminating it can be resolved.

FIG. 1 is a drawing schematically illustrating a cross-section of an adhesive tape using a micropatterned release film according to one embodiment of the present invention.
Figure 2 is a drawing schematically illustrating a cross-section of an adhesive layer according to conventional technology.
FIG. 3 is a drawing schematically illustrating a cross-section of a heteromorphic film according to another embodiment of the present invention.
Figure 4 is a drawing schematically illustrating a cross-section of a heteromorphic film according to the prior art.
FIG. 5 is a micrograph taken at a magnification of 100 of a pattern formed on an upper portion of a heterogeneous layer according to another embodiment of the present invention.
Figure 6 is a micrograph taken at a magnification of 100 of a pattern formed on top of a heterogeneous layer of a prior art.
Figure 7 is a photograph of the surface of an adhesive layer according to Example 2 of the present invention taken at room temperature over time.
Figure 8 is a photograph of the surface of an adhesive layer according to Example 2 of the present invention taken over time at 50°C.
Figure 9 is a photograph of the surface of an adhesive layer according to Comparative Example 2 of the present invention taken at room temperature over time.
Figure 10 is a photograph of the surface of an adhesive layer according to Comparative Example 2 of the present invention taken over time at 50°C.
Figure 11 is a photograph taken after laminating a release film according to Example 1 of the present invention to an adhesive tape.
Figure 12 is a photograph taken after laminating a release film according to Comparative Example 1 of the present invention to an adhesive tape.

A preferred embodiment of the present invention provides an adhesive tape comprising a substrate film and an adhesive layer formed on the substrate film, wherein the adhesive layer comprises a pattern having air passages and micro-air passages connected to the air passages formed on a surface thereof, and the pattern having the micro-air passages connected to the air passages formed includes a shape in which the micro-air passages connect a predetermined section of air passages to another predetermined section of air passages.

The adhesive tape according to the present invention includes a pattern in which air passages and micro air passages connected to the air passages are formed on the upper surface of an adhesive layer formed on one surface of a base film, thereby facilitating the removal of outgasing and resolving problems such as air build-up during lamination to an adherend.

FIG. 1 is a drawing schematically illustrating a cross-section of an adhesive tape to which a release film is applied according to one embodiment of the present invention.

Referring to the above drawing 1, a release film including a base film, a pattern layer, and a release layer, and optionally a primer layer or an antistatic layer, is grafted onto an adhesive layer, which is an upper portion of an adhesive tape, so that the pattern shape of the release film is transferred to the adhesive layer, and a concave structure is formed in a cross-section of the adhesive layer, and an air passage is formed in a deeply recessed portion of the pattern. The air passage refers to a passage through which a gas such as air is discharged to the outside.

In addition, as shown in the above drawing 1, a micro air passage is connected to the air passage to facilitate the flow of gas such as air in the air passage, facilitating discharge to the outside, and even discharge of microscopic air to the outside, thereby significantly reducing the air remaining rate inside the adhesive layer.

The above micro-air passage means an air discharge passage that is connected to the above air passage and through which even micro-air or gas that cannot be discharged through the air passage can be discharged to the outside through the micro-air passage.

It is preferable that the pattern in which the micro-air passages connected to the above air passages are formed includes a form in which the micro-air passages connect a certain section of the air passages to another certain section of the air passages.

If we schematically look at the cross-section of the pattern in which micro-air passages are formed connecting a certain section of the above air passage and a certain section of another air passage, we can see that a number of micro-air passages are formed between the air passages, as shown in Fig. 1.

It is preferable that the pattern in which micro-air passages connected to the above air passages are formed is formed by connecting a plurality of micro-air passages between one side of the air passage and one side of the other air passage.

Since the above multiple micro air passages are formed by being connected to the air passage, even micro air or gas that cannot be discharged through the air passage can be discharged more easily to the outside through the micro air passage.

Figure 2 is a drawing schematically illustrating a cross-section of an adhesive layer according to conventional technology.

Referring to the above drawing 2, a passage is formed in the cross-section of a conventional adhesive layer through which air inside the adhesive layer can be discharged to the outside, but in an adhesive layer with such a pattern, the passage through which gas can be discharged is limited, and since the shape of the pattern is not delicate, there is a limit to discharging even minute air or gas to the outside, so there are disadvantages such as difficulty in removing outgasing and air being trapped when attached to an adherend.

According to one embodiment of the present invention, the adhesive layer includes a pattern formed by connecting a plurality of microscopic air passages between one side of an air passage and another side of an air passage, thereby discharging even microscopic air or gas to the outside, thereby solving the conventional problem.

In addition, the air passages and micro-air passages may each have a concave structure in the shape of a U-shape, a V-shape, a hemisphere, or a square in their cross sections, but are not limited thereto.

The width of the micro air passages is preferably in a ratio of 1:1 to 100, preferably 1:1 to 50, and more preferably 1:2 to 10. When the width of the micro air passages is within the above ratio, the air bubbles captured during lamination on the adherend can have the advantage of moving into the passages and moving out efficiently.

The ratio of the depth of the micro air passage to the depth of the air passage is preferably 1:1 to 50, preferably 1:1 to 20, and more preferably 1:1.2 to 5. When the depth of the micro air passage is within the ratio, it can have the advantage of allowing micro bubbles that were unable to escape during laminating to escape through the passage.

The above adhesive layer is characterized by including at least one selected from an acrylic adhesive, a silicone adhesive, a rubber-based adhesive, a urethane adhesive, and a modified polyester adhesive.

The above-mentioned base film may be at least one selected from among Polyester (PET, PEN, PES, Copolyesters), Polyimide, Polyethylene, Polypropylene, Polyolefin, Polyester (PET, PEN, PES, Copolyesters), Polyamide (Nylon 6, Nylon 66, Aramide), Polyolefine (PE, PP), Polyimide, Poly(vinyl alcohol), Cellulose, Poly(methyl methacrylate), Poly(Vinyl Chloride), but is not limited thereto.

The present invention includes not only the production of a release film having a micro-pattern, but also a thick-film adhesive tape and an integrated tape utilizing the same. The adhesive layer of the thick-film adhesive tape is used by being laminated to a coating layer having a coating thickness of 3 to 400 μm. When the release film having a micro-pattern formed and the thick-film adhesive tape are laminated and stored for a certain period of time, the shape of the surface of the adhesive layer is formed in an opposite shape to that of the micro-pattern layer, which serves to remove air bubbles when laminating (attaching) to an adhesive material of a precision component. Types of the thick-film adhesive layer include a thermosetting acrylic adhesive, a UV-type acrylic adhesive, a thermosetting urethane adhesive, a UV-type urethane adhesive, and a silicone adhesive.

According to another embodiment of the present invention, a release film is provided, comprising: a base film; a pattern layer formed on the base film; and a release layer formed on the pattern layer, wherein the pattern layer includes a pattern having air passages and micro-air passages connected to the air passages formed on a surface thereof, and the pattern having the micro-air passages connected to the air passages formed includes a shape in which the micro-air passages connect a predetermined section of the air passages to another predetermined section of the air passages.

FIG. 3 is a drawing schematically illustrating a cross-section of a release film according to one embodiment of the present invention, and FIG. 4 is a drawing schematically illustrating a cross-section of a release film according to the prior art.

As shown in the above drawings 1 and 3, the release layer of the release film is formed on the surface of the pattern layer with a thickness coated as a thin film and has the same shape as the pattern formed on the upper part of the pattern layer.

In the present invention, the heterogeneous layer is formed in a form coated on the surface of the pattern layer, and the heterogeneous layer can also be used interchangeably with the meaning of having the same pattern as the pattern layer.

The above-described release film includes a release layer having a pattern having the same shape as the pattern formed on the upper part of the adhesive layer in the above-described adhesive tape, except that the pattern of the adhesive layer and the pattern of the release layer are in a positive and negative relationship.

Looking at the above drawings 3 and 4, it can be seen that they show the same aspect as the pattern of the above-described drawings 1 and 2, but they have a positive and negative relationship, and since this corresponds to a common technical matter in the field to which the present invention belongs, a detailed description thereof is omitted.

As shown in FIG. 3, the pattern layer includes a pattern in which an air passage and a micro-air passage connected to the air passage are formed at the upper portion, and the pattern in which the micro-air passage connected to the air passage is formed includes a form in which the micro-air passage connects a certain section of the air passage to another certain section of the air passage.

By transferring a release film including a pattern layer having such a pattern to the adhesive layer of the adhesive tape described above, even minute air or gas that is not discharged through the air passage can be discharged more easily to the outside through the minute air passage.

In this respect, the air passages and micro-air passages of the pattern layer have the same meaning as the air passages and micro-air passages of the adhesive layer described above.

That is, the air passage and micro-air passage illustrated in Fig. 3 are formed by the air passage and micro-air passage illustrated in Fig. 1.

In addition, as shown in Fig. 4, the conventional release film has a limited passage through which air can be discharged from the upper part, is not delicate, so it is not easy to remove outgasing, and has disadvantages such as air being trapped when attached to an adhesive. In addition, the conventional method causes the depth of the pattern to be uneven due to the pressing of PE or the like with heat through thermal compression, which causes defects in the adhesive.

The above pattern layer may include at least one selected from among UV-curable acrylate resin, UV-curable epoxy resin, and EB-curable vinyl resin, but is not limited thereto.

The above pattern layer is characterized by having a thickness of 3 to 200 μm. Do it.

If the thickness of the above pattern layer is less than 3㎛, there is a problem that the bubble removal effect due to the pattern is small, and if it exceeds 200㎛, there is a problem that the coating thickness of the adhesive layer must be relatively thick.

It is preferred that the thickness of the above-mentioned heterogeneous layer is typically 0.1 to 2 ㎛.

There is a problem of release force when the thickness of the above release layer is less than 0.1㎛, and when it exceeds 2㎛, there is a problem of uncured portions occurring or coating water accumulating in the depth of the pattern layer.

The above release layer comprises at least one selected from a thermosetting silicone release resin, a fluorine-based silicone release resin, and a non-silicone release resin. It is.

In addition, the release layer applies a silicone release resin layer or a non-silicon release resin layer to acrylic adhesive tapes or urethane adhesive tapes, and applies a fluorine silicone release resin layer or a non-silicon release resin layer to silicone tapes. In addition, by laminating release resins having various release force ranges, it is possible to impose various release forces on the adhesive tape.

The above-mentioned release film includes a pattern in which micro air passages connected to the air passages are formed on the upper part of the release layer, and the pattern is formed by connecting a plurality of micro air passages between one side of the air passage and one side of the other air passage. When this is applied to an adhesive tape, even micro air or gas that is not discharged through the air passages can be discharged more easily to the outside through the micro air passages.

In addition, the air passages and micro-air passages may each have a concave structure in the shape of a U-shape, a V-shape, a hemisphere, or a square in their cross sections, but are not limited thereto.

The width of the air passage of the above micro-air passage is the same as described above.

The depth of the micro-air passage is the same as that of the air passage described above.

The above-mentioned film is the same as described above.

Additionally, the present invention may further include an antistatic layer between the pattern layer and the release layer.

As shown in the above drawings 1 and 3, various functional thin film layers can be coated on the pattern layer to provide adhesion, surface electrical resistance, and release strength. Among them, a primer layer may be included to provide adhesion, and the primer layer is easy to laminate various types of release layers. In addition, an antistatic layer may be included to provide surface electrical resistance. It is preferred that the thin film coating thickness of the primer layer and the antistatic layer is typically in the range of 0.1 to 2 ㎛.

The above-mentioned anti-static layer has a thickness of 0.1 to 2 ㎛ and is formed on the surface of the pattern layer.

If the thickness of the above anti-static layer is less than 0.1㎛, there is no charging effect, and if it exceeds 2㎛, the layer is too thick and there is no charging effect.

The above-mentioned antistatic layer comprises at least one selected from the group consisting of carbon black of the conductive carbon series, PEDOT, Polyaniline, Polypyrrole of the conductive polymer series, ITO, ATO, Silver of the nano-sized metal series, Amine series, Glycerine series, Amide series, Quaternaryammonium silt, and Phosphite series of low molecular weight surfactant polymers in mixed form as a solvent and binder. It is.

If the above-mentioned anti-static layer is included between the heterogeneous layers, it can have the advantage of imparting permanent anti-static performance.

According to another embodiment of the present invention, a method for manufacturing a release film is provided, including the steps of (S1) forming a pattern layer by coating a UV-curable resin composition on a base film, applying pressure to the upper surface thereof with a mold, and irradiating the substrate with a UV lamp to cure the same, thereby forming a pattern; and (S2) forming a release layer by coating a composition including at least one selected from a thermosetting silicone release resin, a fluorine-based silicone release resin, and a non-silicone release resin on the upper portion of the formed pattern layer.

Conventionally, a release film is usually made of polyethylene (PE) and a pattern is formed through a heat-compression process. Most of these heat-compression processes have the problem of a curling phenomenon occurring on the PE laminated on the base film after heat-compression.

In addition, the pattern formed by the above-mentioned thermal compression process had the problem that the surface or edge of the pattern was very messy and rough due to melting by heat, and the roughness of the pattern was also very poor.

According to another embodiment of the present invention, a method for manufacturing a release film can implement a fine pattern by forming micro air passages connected to the air passages described above using a UV/EB imprinting process that irradiates a UV/EB lamp using a UV-curable resin composition.

FIG. 5 is a photograph taken from above of a release film at a magnification of 100, showing a pattern formed on an upper portion of a release layer according to another embodiment of the present invention, and FIG. 6 is a photograph taken from above of a release film at a magnification of 100, showing a pattern formed on an upper portion of a release layer of the prior art.

As seen in the above drawing 5, the pattern formed on the upper part of the heteromorphic layer according to another embodiment of the present invention can be seen to have a very clean surface and corners or edges of the pattern, and very low roughness, and can have a fine pattern including a form in which the fine air passages connect a certain section of air passage and another certain section of air passage, so that it can have the effect of discharging fine air to the outside as intended by the present invention.

In addition, the method for manufacturing a release film according to another embodiment of the present invention can simplify the process and reduce costs by shortening the production speed compared to the conventional heat pressing process of a release film.

Specifically, the method for manufacturing the above-mentioned heteromorphic film is described as follows: a UV-curable resin composition is coated on a base film, pressure is applied to the upper surface thereof using a mold, and a UV lamp is irradiated to cure the composition, thereby forming a pattern layer (S1).

The above UV-curable resin composition may include, but is not limited to, at least one selected from a UV-curable acrylate resin, a UV-curable epoxy resin, or an EB-curable vinyl resin.

The above-mentioned film is the same as described above.

The above coating process can be performed by selecting a conventional method widely known in the field to which the present invention belongs, and an example thereof includes a coating method using a micro gravure coater, but is not limited thereto.

The pattern layer is formed by applying pressure to the upper surface of the above-mentioned coated layer with a mold, irradiating it with a UV lamp, and curing it to form a pattern.

The above mold may be a mold with a pattern engraved therein for any purpose, and in another embodiment of the present invention, a mold with a pattern engraved therein in which micro-air passages connected to air passages are formed as described above may be used, and the micro-air passages on the upper part of the release layer may have a pattern including a form in which a certain section of air passages connects another certain section of air passages.

The process of irradiating the UV lamp is preferably performed with a source of 0.1 J/cm2 or more at a wavelength of UV (ultraviolet ray: light with a wavelength of 200 to 450 nm) or EB (electron beam: wavelength of 10 ^-3 to 10 ¹⁰ nm) for 0.1 second to ¹ minute.

If the time of the above process is within the above range, the advantage of increasing productivity to a curing rate of 94% or more can be obtained.

The above wavelength range can obtain the advantage of increasing productivity to a curing rate of 94% or more that satisfies the above conditions.

If the range of the above investigation amount satisfies the above conditions, the advantage of increasing productivity to a curing rate of 94% or more can be obtained.

If the above source satisfies the above conditions, the advantage of increasing productivity to a curing rate of 94% or higher can be obtained.

The pattern layer formed above is characterized by having a thickness of 3 to 200 μm from the substrate film. Do it.

If the thickness of the above pattern layer is less than 3㎛, there is a problem that the bubble removal effect due to the pattern is small, and if it exceeds 200㎛, there is a problem that the coating thickness of the adhesive layer must be relatively thick.

A release layer is formed by coating a composition including at least one selected from a thermosetting silicone release resin, a fluorine-based silicone release resin, and a non-silicone release resin on top of the pattern layer formed above (S2).

The above coating process can be performed in the same manner as described above.

The formed heterogeneous layer has a thickness of 0.1 to 2 μm and is formed on the surface of the pattern layer.

There is a problem with the release force when the thickness of the release layer is less than 0.1㎛, and when it exceeds 2㎛, there is a problem with the occurrence of uncured portions or the coating water accumulating in the depth of the pattern layer.

The above release layer comprises at least one selected from among a thermosetting silicone release resin, a fluorine-based silicone release resin, and a non-silicone release resin. It is.

At this time, a process of coating an antistatic layer on top of the pattern layer can be additionally performed before forming the heterogeneous layer.

The above coating process can be performed in the same manner as described above.

The above-mentioned anti-static layer has a thickness of 0.1 to 2 ㎛ and is formed on the surface of the pattern layer.

If the thickness of the above anti-static layer is less than 0.1㎛, there is no charging effect, and if it exceeds 2㎛, the layer is too thick and there is no charging effect.

The above-mentioned antistatic layer includes at least one selected from the group consisting of carbon black of the conductive carbon series, PEDOT, polyaniline, polypyrrole of the conductive polymer series, ITO, ATO, silver of the nano-sized metal series, amine series, glycerine series, amide series, quaternaryammonium silt, and phosphate series of low molecular weight surfactant polymers, as a solvent and binder in a mixed form.

If the above-mentioned anti-static layer is included between the heterogeneous layers, it can have the advantage of imparting permanent anti-static performance.

Example

Hereinafter, the present invention will be described in more detail through examples. These examples are only intended to explain the present invention more specifically, and the present invention is not limited thereby.

<Example 1; Production of a release film>

A UV-curable resin composition was prepared by mixing 100 parts by weight of urethane acrylate oligomer synthesized with polytetrahydrofuranol series, IPDI (Isophorone diisocyante) series and 2-Hydroxyethylacrylate (weight average molecular weight 7,000 to 8,000), 15 parts by weight of monoacrylate dilution monomer (IBOA, Isobornyl acrylate), 10 parts by weight of diacrylate-based additive oligomer (bisphenol A type epoxy acrylate (Biphenol A type epoxy acrylate, Cytec EB600), 10 parts by weight of viscosity-controlling dilution monomer (2-Hydroxyethylacrylate), and 3 parts by weight of UV initiator (Irgacure 184, manufactured by IGM). The prepared UV-curable resin composition was coated on a PET (polyethylene terephthalate) base film with a thickness of 13 μm, and then applied to a coating film. As shown in Fig. 5, after chemical etching was performed on the roll with a pattern, a UV imprinting device using a roll-to-roll method was used to perform pattern coating on the upper surface of the surface on which a UV-curable resin composition was coated on a PET substrate with a width of 1 m. The pattern was transferred onto the PET using a UV acrylic resin.

To explain in more detail, in order to transfer the pattern onto PET, the pattern formation is engraved on a roll and applied to the upper roll of the UV imprinting equipment rolls. In order to transfer the pattern engraved on the roll onto PET, UV acryl resin is placed between the rolls. At this time, a light amount of 600 mJ or more and three UV wavelengths of 254 nm, 365 nm, and 405 nm are irradiated simultaneously to harden the UV acryl resin transferred onto the PET as a pattern model .

In order to produce a pattern layer coating thickness of 13㎛ for the UV imprinting pattern, the production speed was set to 5mpm. At this time, the UV light irradiation time was set to approximately 4 seconds.

The pattern of the pattern layer formed above has a pattern as shown in Fig. 5, and the air passages and micro-air passages each have a convex structure with a cross-section in the shape of a square, and the width of the micro-air passages to the width of the air passages is formed in a ratio of 1:3, and the depth of the micro-air passages to the depth of the air passages is formed in a ratio of 1:1.4. A release coating agent is coated on the surface of the formed pattern layer by applying a micro-gravure coater to form a release layer. The above release coating agent is a mixture of 100 parts by weight of a silicone-based main agent (Syl-Off SD 7226 Dow Corning), a Pt-series addition polymerization method, 7 parts by weight of an auxiliary main agent (SYL-OFF® 7210 Dow Corning), 1 part by weight of a crosslinking agent (SYL-OFF® 7689 Dow Corning), 1 part by weight of an anchor agent (A-187, Momentive), 3000 ppm by weight of a platinum catalyst, and 700 parts by weight of an organic solvent MEK (Methylethylketone), and a composition having a release force of 30 gf/in based on TESA 7475 Tape was applied to produce a release layer having a thickness of 0.5 μm. Specifically, under the drying conditions, a temperature of max. 155 degrees and a production speed of 50 mpm, an air-free release film of 125 μm was produced.

<Example 2; Manufacturing of air-free adhesive tape>

A pressure-sensitive adhesive layer was formed by mixing 100 parts by weight of an adhesive (CMT-0457B, Cosmotech Co., Ltd.), 0.5 parts by weight of an epoxy curing agent (NA-30, Cosmotech Co., Ltd.), 1.0 parts by weight of an isocyanate curing agent (NA-1045L, Cosmotech Co., Ltd.), and 0.1 parts by weight of an adhesion promoter (A-187, Momentive) on the upper surface of a 40 μm substrate layer coated in a four-color thin film with 2 μm black ink on a PET substrate film, and using a comma coater, and drying the resulting adhesive layer to a thickness of 90 μm. The release film manufactured in Example 1 was then laminated on the upper surface of the adhesive layer, which was then left at 50°C for 2 days, to manufacture an air-free single-sided tape.

<Comparative Example 1>

First, an acrylic pressure sensitive adhesive solution (described as Adhesive Solution 1 in U.S. Patent No. 5,296,277, modified with 18.5 phr of resin; NirezTM 2019 manufactured by Arizona Chemical Corporation) was prepared.

A release liner comprising four layers, a 97 ㎛ poly(ethylene terephthalate) core, a 21-22 micron polyethylene with a matte finish on the back side, a 21-22 ㎛ polyethylene with a glossy finish on the front side and a silicone release coating on the glossy side, was microembossed on the glossy side by passing the release liner between a silicone rubber roll having a hardness of 85 and a diameter of 15 cm and an engraved metal roll having a diameter of 15 cm. The engraved design on the metal roll was intersecting sunken lines (microgrooves) forming a square grid with the microgrooves at a 45° angle to the circumference of the roll.

The above silicone rubber roll and the cut roll were heated to temperatures of 121°C and 110°C, respectively. A pressure of about 22 N/mm was applied to the rolls by a cylinder. The release liner passed through the above array at about 1.6 cm/sec.

The above-mentioned manufactured acrylic pressure-sensitive adhesive solution was coated on each micro-embossed release liner and dried at 66°C for 10 minutes to manufacture a release film having a thickness of approximately 32 μm.

<Comparative Example 2>

A pressure-sensitive adhesive layer was formed by mixing 100 parts by weight of an adhesive (CMT-0457B, Cosmotech Co., Ltd.), 0.5 parts by weight of an epoxy curing agent (NA-30, Cosmotech Co., Ltd.), 1.0 parts by weight of an isocyanate curing agent (NA-1045L, Cosmotech Co., Ltd.), and 0.1 parts by weight of an adhesion promoter (A-187, Momentive) on the upper surface of a 40 μm substrate layer coated with 2 μm black ink in a four-degree thin film on a PET substrate, and using a comma coater, the adhesive layer was laminated and coated with a dried coating thickness of 90 μm. Then, a release layer manufactured in Comparative Example 1 was laminated on the upper surface of the adhesive layer, and left at 50°C for 2 days to manufacture an adhesive tape.

<Comparative Example 3>

A pressure-sensitive adhesive layer was formed by mixing 100 parts by weight of an adhesive (CMT-0457B, Cosmotech Co., Ltd.), 0.5 parts by weight of an epoxy curing agent (NA-30, Cosmotech Co., Ltd.), 1.0 parts by weight of an isocyanate curing agent (NA-1045L, Cosmotech Co., Ltd.), and 0.1 parts by weight of an adhesion promoter (A-187, Momentive) on the upper surface of a 40 μm substrate layer coated with 2 μm black ink in a four-color thin film on a PET substrate, and using a comma coater, and then laminating the resulting adhesive layer to a dried coating thickness of 90 μm. Then, a 125 μm thick general silicone release layer was laminated on the upper surface of the adhesive layer, and left at 50°C for 2 days to manufacture an adhesive tape.

<Measurement example>

The release films and adhesive tapes manufactured from the above examples and comparative examples were subjected to a property evaluation according to the following method, and the results are shown in Figs. 7 to 12 and Tables 1 to 3.

(1) Measurement of bubble removal speed: The release film was peeled off from the adhesive tape manufactured according to the examples and comparative examples, the tape was attached to a glass plate, and the tape was left at room temperature and 50°C to measure the degree of bubble removal using a shape analysis application program of the specimen using Model No. VK-8700 of KEYENCE Corporation.

(2) Measurement of residual adhesive strength: The residual adhesive strength is considered to be 100 when the adhesive strength of the adhesive tape manufactured according to Comparative Example 3 is considered to be 100. The release film manufactured according to Example 1 and Comparative Example 1 and the tape are attached to a SUS board and then left in an oven at 70°C for 20 hours. After 20 hours, they are taken out of the oven and left at room temperature of 25°C for 4 hours and then the physical properties are evaluated. The physical properties were evaluated according to the ASTM D3330 standard, and the changes in the physical properties compared to the initial adhesive strength were evaluated.

(3) Residual score (%): Measured under the following conditions.

Test 1. Attaching 2kg of tape to SUS

Test 2. Attach 2kg of tape to SUS and remove air bubbles with your fingernail.

Test 3. After attaching 2kg of tape to SUS, air bubbles were removed at 7.7mpm at Lami. O pressure.

Test 4. After attaching 2kg of tape to SUS, Lami. Remove air bubbles at 7.7mpm speed under 0.3MPa pressure.

division Attachment area ratio Room temperature 50℃ Example 2 10 minutes 50% 1 minute 70% 24 hours 80% 24 hours 80% Comparative Example 2 10 minutes 20% 1 minute 15% 24 hours 80% 24 hours 80%

division Residual adhesion (gf/inch) Test 1 Test 2 Test 3 Test 4 Example 2 2326 2340 2305 2340 Comparative Example 2 1848 2182 2161 1881

division Residual rate (%) Test 1 Test 2 Test 3 Test 4 Example 2 83 84 82 84 Comparative Example 2 66 78 77 67

As can be seen from Tables 1 to 3 above, Example 2 showed that most of the bubbles generated during lamination were removed, but Comparative Example 2 showed that most of the bubbles generated during lamination remained.

In addition, FIG. 7 is a photograph of the surface of an adhesive layer according to Example 2 of the present invention taken at room temperature over time, and FIG. 8 is a photograph of the surface of an adhesive layer according to Example 2 of the present invention taken at 50°C over time.

In addition, FIG. 9 is a photograph of the surface of the adhesive layer according to Comparative Example 2 of the present invention taken at room temperature over time, and FIG. 10 is a photograph of the surface of the adhesive layer according to Comparative Example 2 of the present invention taken at 50°C over time.

As seen in the above drawings 7 to 10, Example 2 has more passages including micro-air passages than Comparative Example 2, so it can be confirmed that bubble removal during lamination is relatively improved. However, it can be seen that Comparative Example 2 has a problem in that bubbles generated during lamination are not easily removed.

In addition, FIG. 11 is a photograph taken after laminating a release film according to Example 1 of the present invention to an adhesive tape, and FIG. 12 is a photograph taken after laminating a release film according to Comparative Example 1 of the present invention to an adhesive tape.

As seen in the above Figures 11 and 12, when the release film according to Example 1 was laminated to the adhesive tape, it could be seen that air bubbles remained only in some parts, but when the release film according to Comparative Example 1 was laminated to the adhesive tape, it could be seen that there was a problem of air bubbles remaining throughout the entire adhesive tape.

Claims (16)

delete delete delete delete delete delete Step (S1) of forming a pattern layer by coating a UV-curable resin composition on a substrate film, applying pressure to the upper surface thereof with a mold, and curing by irradiating with a UV lamp to form a pattern; and
A method for manufacturing a release film, comprising a step (S2) of forming a release layer by coating a composition including at least one selected from a thermosetting silicone release resin, a fluorine-based silicone release resin, and a non-silicone release resin on the upper portion of the formed pattern layer,
The process of irradiating the UV lamp in the above S1 step is performed with a UV (ultraviolet ray: light with a wavelength of 200 to 450 nm) source for 0.1 second to 1 minute.
The above heteromorphic film is a base film;
A pattern layer formed on the above substrate film; and
Including a heteromorphic layer formed on the above pattern layer,
The above pattern layer includes a pattern in which air passages and micro air passages connected to the air passages are formed on the surface,
A method for manufacturing a heteromorphic film, wherein the pattern in which micro-air passages connected to the above air passages are formed includes a form in which the micro-air passages connect a certain section of air passages to another certain section of air passages. delete A method for manufacturing a special film, characterized in that in claim 7, the air passages and micro-air passages each have a convex structure in the shape of a U-shape, a V-shape, a hemisphere, or a square in their cross sections. A method for manufacturing a release film, characterized in that in claim 7, the width of the micro-air passage is in a ratio of 1:1 to 100. A method for manufacturing a release film, characterized in that in claim 7, the depth of the micro-air passages is in a ratio of 1:1 to 50. A method for manufacturing a release film, characterized in that in claim 7, the pattern layer includes at least one selected from a UV-curable acrylate resin, a UV-curable epoxy resin, or an EB-curable vinyl resin. A method for manufacturing a release film, characterized in that in claim 7, the release layer has a thickness of 0.1 to 2 ㎛. delete delete delete