KR20070111228A - Method for pretreating optical film and method and facility for manufacturing lamination of optical film using the same method - Google Patents

Abstract

A method for pretreating an optical film using plasma, and a method and a facility for manufacturing lamination of an optical film using the same method are provided to perform a film pretreatment process of a fabrication process of a transparent optical film stack, without causing environmental pollution. A plurality of film supplying units(80) supplies films(10,20,30) by rotating a bundle of rolled films. More than one atmospheric pressure plasma apparatus(70) is located in the rear of a film supplying path of the film supplying unit. An adhesion unit supplying unit(60) supplies an adhesion unit between films by being located in the rear of the film supplying path of the plasma apparatus. A compression roll(40) compresses each film stack part in order to bond each interface supplied with the adhesion unit sufficiently.

Description

Method for pretreatment of optical film using plasma and method for manufacturing optical film laminate using same and manufacturing equipment TECHNICAL FIELD

1 is a schematic view showing a conventional manufacturing facility for producing a film laminate, such as a polarizing plate laminate. And

2 is a schematic view showing equipment for producing a film laminate provided by the present invention.

(Explanation of the sign)

10: upper film, 20: center film (or polarizing plate),

30: lower film, 40: pressing roll

50: winding roll, 60: bonding means supply means

70 plasma apparatus 80 film supply means

The present invention relates to a pretreatment method of an optical film using plasma, and an optical film laminate manufacturing method and manufacturing equipment using the same, and more particularly, a plurality of sheets such as a polarizing plate protective film, a plasma display film, or an organic EL display film. In order to improve the adhesion between the substrate and the optical film before adhering the optical films to each other, the waste liquid or the like may be used by using plasma instead of the conventional pretreatment method of activating the surface of the protective film using an alkali solvent. The present invention relates to a pretreatment method and a method and apparatus for manufacturing a polarizing plate laminate using the same, which can be realized by a simple installation without causing environmental problems.

A polarizer is an essential component that represents pixels by controlling polarization of light in a liquid crystal display together with a liquid crystal. In more detail, the polarizing plate is a component that is attached to upper and lower liquid crystal cells to polarize the light emitted from the backlight and the like to the backlight side polarizing plate, and then controls the polarization direction by the liquid crystal to determine whether the light passes through the observer side polarizing plate.

Polyvinyl alcohol (PVA) is mainly used as the polarizing plate. Since PVA is weak in strength, a protective film such as TAC is attached to the upper and lower portions thereof. In addition, in recent years, in addition to the protective film, a case where a functional film is added to one or both sides of the polarizing plate in order to perform various functions, for example, a retardation film, has been applied. Therefore, the polarizing plate is generally used in the form of a laminate rather than being used alone.

In order to manufacture the polarizing plate as described above, the protective films 10 and 30 are adhered to the upper and lower portions of the polarizing plate 20 located in the center by using the method shown in FIG. 1, and the protective film is mainly attached by using the pressing force of the roll. Let's do it. At this time, the adhesive may be improved by supplying an adhesive 60 between the polarizing plate and the protective film. At this time, it is necessary to activate the film surface in order to improve the adhesion performance between the two films.

This activation process is called pretreatment because it must be carried out before the pressing by the pressing roll 50 and the adhesive supply. In addition to the polarizing plate laminate, a transparent optical film forming a laminate such as a film for plasma display and an optical film for organic EL display is used. Most of the work is done before manufacturing.

In the pretreatment, a method of depositing a protective film such as TAC in a strong alkaline solution is commonly used. By the way, the conventional pretreatment method has a problem that there is a risk that the waste liquid is discharged in a large amount when the protective film is deposited on the alkaline solution to cause various environmental pollution. In addition, in the case of using the conventional pretreatment method, activation of norbornene-based resin film is very difficult, and the molecule consisting of an acrylate resin film or liquid crystal is pretreatment by the conventional method. Was not possible.

As a new method to solve this problem, Japanese Patent Application Laid-Open No. 2003-255131 discloses a plasma by applying a high frequency voltage of 1 kHz to 150 MHz under an atmosphere in which a reaction gas containing an organic compound having an unsaturated bond exists at a pressure near atmospheric pressure. Disclosed is a method for treating a film surface characterized by performing discharge treatment. According to the present method, since the film surface is activated when the film surface is plasma treated, the adhesive property by the adhesive may be greatly improved.

However, as described in the claims, the present invention is a method of generating a plasma in an atmosphere in which a reaction gas containing an organic compound having an unsaturated bond is present, so that the airtightness of the reaction chamber is prevented in order to prevent contamination by the organic compound. In addition to maintaining, the film must be unfolded and reacted in the chamber, so that the size of the chamber or the area of the film that can be processed at one time can be reduced, resulting in reduced productivity and complicated construction of the equipment. Has a problem. In addition to the above technique, there is a further problem that environmental pollution may occur due to the reaction gas remaining after treatment.

The present invention is to solve the problems of the prior art described above, the film pre-treatment process of the manufacturing process of the transparent optical film laminate, such as a polarizing plate laminate, a film for plasma display or a film for organic EL display without causing environmental pollution It is an object of the present invention to provide a method which can be easily carried out, a method for producing an optical film laminate and a device for producing the same.

In addition, the present invention not only has superior adhesiveness than the prior art, but also the reworkability of detaching and then reattaching the attached protective film also has a superior pretreatment method and a method for manufacturing an optical film laminate using the same, and a device for manufacturing the same. To provide another purpose.

As a first aspect of the present invention for achieving the above object, the pretreatment method of the present invention is characterized by supplying oxygen radicals to the film surface by using an atmospheric plasma generator.

At this time, the main gas for the plasma treatment is preferably helium, argon or nitrogen.

For effective pretreatment, it is necessary to set the operating frequency range in the range of 1 kHz to 100 MHz, and in particular, when the main gas is helium or argon, the operating frequency range is preferably in the range of 1 MHz to 100 MHz, and the main gas may be nitrogen. In this case, the operating frequency range is preferably in the range of 1 kHz to 1 MHz.

In addition, the flow rate of the main gas is preferably 1 to 50 standard liters per 1 m ² (1 standard liter: 1 liter at 0 ° C and 1 atm).

In addition, it is necessary to use oxygen or dry air (CDA) as the reaction gas for oxygen radical supply.

At this time, it is effective that the flow rate of the reaction gas is 1/1000 to 1/10 of the main gas flow rate.

Further, the spacing between the plasma discharge face and the film face to be treated is preferably in the range of 0.1 mm to 10 mm, more preferably in the range of 0.5 mm to 5 mm.

The treatment speed of the appropriate film according to the pretreatment method of the present invention is preferably in the range of 0.5m / min ~ 50m / min.

Another aspect of the present invention provides a method of manufacturing a polarizing plate laminate comprising: a film supplying step of supplying a plurality of films; A pretreatment step of activating the adhesion surface of each film by supplying oxygen radicals generated from the atmospheric pressure plasma apparatus; An adhesive means supplying step of supplying an adhesive means between each film; And a pressing step of uniformly compressing the film interface supplied with the adhesive means by the pressing roll.

Here, the adhesive means may include both an adhesive or an adhesive.

At this time, the main gas for the plasma treatment is preferably helium, argon or nitrogen.

In addition, it is effective to set the operating frequency range in the range of 1 kHz to 100 MHz. In particular, when the main gas is helium or argon, it is necessary to set the operating frequency range in the range of 1 MHz to 100 MHz. It is desirable to set the operating frequency range in the range of 1kHz to 1MHz.

In addition, the reaction gas for the plasma treatment is preferably oxygen or dry air.

In the film laminated body manufacturing method of the said preferable invention, the space | interval between a plasma discharge surface and the film surface to process is 0.5 mm-5 mm range.

Another aspect of the present invention is a film laminate manufacturing apparatus comprising a plurality of film supply means for supplying a film by rotating a roll of film wound in the form of a roll; One or more atmospheric plasma apparatuses positioned behind the film supply path of the film supply means; Bonding means supply means positioned behind the film supply path of the plasma apparatus to supply the bonding means between the films; And a pressing roll for pressing each film lamination part so that each interface supplied with the adhesive means can be sufficiently bonded.

At this time, it is preferable that the winding roll further includes a winding roll for winding the laminated film.

Here, the adhesive means may include both an adhesive or an adhesive.

Hereinafter, the present invention will be described in detail.

The inventors of the present invention have a problem in that continuous operation is difficult because the device must be sealed when the organic compound is used as in the invention described in Japanese Patent Laid-Open No. 2003-255131, and the film surface must be activated in the sealed device. The present invention has been focused on.

That is, the inventors of the present invention, when using an atmospheric plasma apparatus capable of supplying oxygen radicals, not organic compounds, under atmospheric pressure for pretreatment, there is no problem of environmental pollution due to the remaining by-products, and the reaction proceeds in an open state. It was found that continuous work was possible.

The concept of the manufacturing method and manufacturing apparatus of the polarizing plate laminated body which used the pretreatment method and pretreatment method of this invention which the inventors of this invention proposed based on the above examination result is as having described in FIG.

Atmospheric pressure plasma apparatus used in the present invention is currently developed and commercialized, for example, the plasma generating apparatus described in Korean Patent Publication No. 2002-0041537 or 2001-0084566 can be used.

In the case of using the atmospheric plasma apparatus, it is possible to form oxygen radicals having a high ion density even under atmospheric pressure, so that oxygen radicals can be supplied to the surface of the film.

As a power supply device used to supply oxygen radicals using the atmospheric pressure plasma apparatus, a voltage having a bipolar pulse, a unipolar pulse, or a sine wave may be used. Although there may be slight differences depending on the type of main gas used, it is appropriate to set the operating frequency range in the range of 1 kHz to 100 MHz to enable uniform treatment on the film surface. That is, an inert gas is used as the main gas for plasma treatment, and helium, argon, or the like is preferably used. In addition, nitrogen gas may also be used. When using helium or argon, the operating frequency range is preferably 1 MHz or more, and when using nitrogen, it is preferably between 1 kHz and 1 MHz.

The amount of the main gas used to form an appropriate amount of plasma varies slightly depending on the type of the main gas, but is generally 1 to 50 standard liters per 1 m ^{2 of} treatment area (1 standard liter: 1 liter at 0 ° C and 1 atm). It is preferable.

In order to activate the surface of the film, it is preferable to use oxygen (O 2) or dry dry air (CDA) as the reaction gas to be plasma-treated, and as the amount of the reaction gas increases, the activation effect of the film increases. In order to ensure uniformity according to the amount of 1/1000 ~ 1/10 of the main gas amount is particularly preferred. However, the reaction gas is not necessarily to be used, and even if there is no reaction gas, some degree of plasma treatment effect can be obtained.

In addition, in order to perform plasma treatment so that the film processed by heat or high energy is sufficiently damaged without being damaged, it is necessary to control the amount of current to about 1 mA to 10 A and to set the driving power to be in the range of 400 W to 10 kW. This is because if the amount of current and the driving power is less than the above range, the plasma treatment effect is weak and it is difficult to improve the adhesion. On the contrary, if the amount of the current and the driving power exceeds the above range, the processed film is easily damaged.

In addition, since plasma easily loses stability in the atmosphere, it is necessary to treat the plasma within a close distance. In consideration of the emission and stability of oxygen radicals, the distance between the plasma discharge surface of the plasma apparatus and the film surface to be treated is preferably between 0.1 mm and 10 mm. In order to height, it is more preferable to set it as 0.5 mm-5 mm.

The proper treatment speed (pretreatment speed) of the film to be treated under the appropriate plasma generation conditions as described above is better in the pretreatment with lower speed, but considering productivity, treatment uniformity and stability, 0.5m / min ~ 50m / min Is preferably.

The method of manufacturing the film laminate of the present invention using the above-described pretreatment method may be performed in the following order.

First, the step of supplying a plurality of films is preceded. At this time, if the polarizing plate laminated body is manufactured to supply the polarizing plate to be positioned between the upper film and the lower film (film supply step). Thereafter, the adhesion surface of each film is activated by supplying oxygen radicals generated from the atmospheric plasma apparatus (pretreatment step). A bonding means is supplied between each film as needed (adhesive means supplying step). The bonding means supplied in the present bonding means supplying step is meant to encompass both materials for bonding both films, and includes a conventional adhesive or an adhesive such as PSA. Subsequently, if the interface supplied with the bonding means is uniformly compressed by a pressing roll, a film laminate having good adhesion strength can be obtained (pressing step).

At this time, the pretreatment step of activating the adhesion surface of the film by the oxygen radicals generated from the plasma apparatus may be carried out by the preferred conditions of the pretreatment step described above.

In addition, when the laminate is attached to a substrate such as a glass substrate, in order to improve adhesiveness and reworkability to an adhesive such as PSA, an additional surface of the film to be attached to the substrate is further plasma pretreated. It can also be activated.

The manufactured laminate may be wound by a predetermined winding roll provided thereafter and stored in a roll form.

In addition, the method of manufacturing the polarizing plate laminate as described above may be more effectively implemented by the manufacturing equipment of the polarizing plate laminate described below.

Each film is supplied by a plurality of film supply means 80 located in front. The film supply means 80 supplies the films 10, 20, and 30 by rotating the rolled film bundles. The film supply means may adjust the number in accordance with the number of layers of the film to be laminated. The atmospheric pressure plasma apparatus 70 is positioned behind the film supply path of the film supply means 80 for pretreatment. The plasma supply surface of the plasma apparatus is positioned facing the film surface to be pretreated. One or more plasma devices may be installed depending on the number of films to be pretreated. As seen from the film supply path, the adhesive means supply means 60 may be located behind the plasma apparatus. The adhesive means supply means is the same as the adhesive means supply means 60 used in manufacturing a conventional film laminate. The adhesive means supplied by the present adhesive means supply means encompasses both materials to adhere the two films, and includes an ordinary adhesive or an adhesive such as PSA. Thereafter, a pressing roll 40 for pressing each film lamination part is positioned so that each interface supplied with the bonding means is sufficiently bonded. Finally, a winding roll for winding the laminated film and storing it in a roll form as necessary. 50 may be located. The method of manufacturing the film laminate of the present invention by the above-described equipment configuration can be more easily implemented.

The present invention described above is a method of using atmospheric plasma instead of the conventional pretreatment method when manufacturing the film laminate, and the functionality for adding other functions to the polarizing plate or the protective film for a polarizing plate, as well as other polarizing plates commonly used. Any film can be the object of the present invention as long as it is about a film constituting the polarizing plate laminate, such as a film, and it will be understood by those skilled in the art.

In addition, the film pretreatment method and the laminate manufacturing method of the present invention are not necessarily applied to the production of a polarizing plate of a liquid crystal display device, but are applied to other substrates or films as a transparent optical film for use in organic EL displays, plasma displays, and the like. All can be applied to the pretreatment method of the film forming a sieve.

(Example)

plasma  Reliability Review

Influence of the input frequency and driving power, the kind and amount of the main gas, and the kind and amount of the reaction gas on the plasma stability under the conditions shown in Table 1 were investigated. In this example, the film surface having a width of 400 mm was treated at a speed of 5 m / min. Slm, the unit of the reaction gas quantity shown in the table, means standard liter per minute.

division Input frequency Driving power Main gas type Main gas volume Reaction gas type Reaction gas amount Plasma stability Example 1 15 MHz 1 kW He 5 slm O ₂ 0.3 slm stability Example 2 13.5 MHz 0.6 kW He 15 slm O ₂ 0.5 slm stability Example 3 14 MHz 0.4 kW Ar 15 slm O ₂ 0.05 slm stability Example 4 13 MHz 3 kW He 30 slm O ₂ 0.8 slm stability Example 5 13.5 MHz 3.5 kW He 20 slm CDA 0.8 slm stability Example 6 50 kHz 0.5 kW N ₂ 400 slm CDA 1 slm stability Example 7 40 kHz 10 kW N ₂ 1000 slm O ₂ 0.5 slm stability Example 8 13.5 MHz 3 kW He 20 slm - - stability Comparative Example 1 13.5 MHz 0.3 kW Ar 5 slm O ₂ 0.2 slm Instability Comparative Example 2 50 kHz 0.6 kW N ₂ 1100 slm O ₂ 0.5 slm Instability Comparative Example 3 14 MHz 0.2 kW He 15 slm O ₂ 0.05 slm Instability Comparative Example 4 13.4 MHz 1 kW He 4 slm - - Instability

In Table 1, the stability of the plasma can be determined from the results of observing the uniformity of the plasma formed in the gap between the plasma processor and the film surface with the naked eye. That is, it can be seen that the plasma is nonuniform in A, B, and C of FIG. 3, but a uniform plasma is formed in D. The case where the plasma of the same type as D is generated is set as a stable case. Glow to Arch discharge occurs when the plasma state is stable, and even plasma is observed throughout the gap as shown in Fig. D. However, the conditions such as voltage (V) and frequency (Hz) are the conditions for plasma generation. If it does not match, a plasma streamer will be generated. In this case, as shown in Figures A, B, and C, it is easy to observe the part where no plasma is generated. In general, the main gas used in the plasma is to use an inert gas, the plasma state of the gas is a bright light of violet (Violet) or purple (Magenta), so the plasma stability can be easily seen with the naked eye.

In Examples 1 to 8, the plasma was generated under the appropriate conditions provided by the present invention, and when the plasma was generated by the above embodiments, the stability of the plasma was excellent.

However, Comparative Example 1 is a case where the driving power is lower than the case specified in the present application, Comparative Example 2 is a case where the main gas usage is excessive, Comparative Example 3 is also a case where the driving power is low, similar to Comparative Example 1 as a reaction gas In the case of using He gas, Comparative Example 4 shows a case where the amount of main gas used is less than the prescribed amount of the present application. The plasma generated by each of the comparative examples was insufficient in stability.

Therefore, as described above, it was found that the plasma stability was very excellent when the plasma was generated under the appropriate conditions provided by the present invention.

Evaluation of adhesion performance with polarizer

Using the polarizing plate laminate manufacturing equipment of the present invention shown in Figure 2 by performing a plasma treatment to the protective film under the conditions of Table 2, after the polarizing plate laminated body through the adhesive treatment and compression step to evaluate the adhesion performance It was.

As can be seen from the table, as the treating film used in this evaluation, triacetyl cellulose (TAC), COP, acrylate film, liquid crystal film and PC film were used.

Among them, a TAC in the form of a film manufactured by Fuji, Japan was used as the TAC. Although there are several kinds of TACs having different manufacturers, optical properties, and thicknesses, the 80 μm normal TAC of the above company was used in this embodiment. Although not described separately in this embodiment, it was also confirmed that other types of TACs showed the same tendency as the results of this embodiment.

As another treatment film, cycloolefin polymer (COP), 40 μm thick isotropic COP manufactured by Zeon Japan was used.

In addition, as an acrylate film, a film obtained by coating an acrylate resin on a film such as TAC, COP, PET, PC, and curing the same was used. In this case, the acrylate resin may be any of various monomers, oligomers, or polymers having a functional group of 1 to 5, 6 or more. In addition, in order to film the acrylate resin, a curing process is required after coating. At this time, both heat curing using heat and UV curing using light with UV (Ultra Violet) are possible. In the present experiment, the oligomer acrylate resin was UV cured on the TAC substrate because the UV curable acrylate was inferior to the adhesive means (adhesive or adhesive) than the thermal curable acrylate. Although film-formed hard coating acrylates were used, it is natural that other types of acrylates could be expected to have the same or better plasma treatment performance.

In addition, the liquid crystal film evaluated the performance using both the thing which this applicant manufactured, and the product of Fuji Corporation. Both companies produced similar results for plasma treatment.

Lastly, as the PC, a PC in the form of a film made by Teijin, Japan, there are various kinds of PCs having different optical properties and thicknesses, but in this experiment, a 70 μm stretched PC was used.

Plasma treatment on the protective film under the plasma treatment conditions shown in Table 2 for each embodiment, and then PVA adhesive (Sigma Aldrich, Poly Vinyl Alcohol Average Mw = 85,000 ~ 124,000, 5% aqueous solution) to the polarizing element (PVA) film Using, after the protective film and the polarizing device was attached, dried for 5 minutes in an oven at 80 ℃, taken out and cut off the edge, cut to about 100mm x 100mm. At this time, the edge of the protective film and the polarizing element that is not the adhesive treatment is left about 20 mm. Then, three days at room temperature, the PVA adhesive was completely cured to obtain an adhesion evaluation sample.

The adhesion force evaluation sample was used to evaluate the polarizing element (PVA) and the adhesion force in the following manner.

Often, a peeling test method is a method of evaluating the adhesion performance between two films. Peeling test is a device that measures the adhesion between two sides by measuring the force at the point where the surface starts to crack by fixing one side to the floor, holding the other side and applying force gradually to evaluate the adhesion of the two interfaces to be.

However, in order to evaluate the adhesion performance by this method, in order to secure reference data, when the peeling test between the polarizing element (PVA), which is a component of the polarizing plate, and the TAC protective film, a peeling tester Before the evaluation of the bonding force between the two films, the tearing of the TAC protective film was observed. Due to the nature of the TAC film, it was torn when strong forces were formed, so it was impossible to obtain reference data for the peeling test.

Therefore, in order to evaluate the adhesion between various protective films and the polarizing element (PVA), when peeling test is performed on the sample after the hardening of the PVA adhesive is completely completed, the peeling part is said to be "no adhesion", and the peeling test It was called "good" if the phenomenon beyond the measurement area of or torn was observed.

Durability measurement

After obtaining the evaluation sample in the same manner as before, the commercial adhesive for the polarizing plate is attached to the protective film attached to the polarizing element so as not to bubble. The sample thus made was cut to a size of 100 mm x 100 mm, and then attached to a glass substrate (110 mm * 190 mm * 0.7 mm) so that the optical absorption axis of the polarizer was cross. At this time, the applied pressure was about 5㎏ / ㎠ to perform the operation in the clean room so that no bubbles or foreign matter was obtained a specimen. In order to determine the heat and moisture resistance of the specimen, the specimen was left to stand at 60 ° C. and 90% relative humidity for 1,000 hours, and then visually observed whether bubbles or peeling occurred. In addition, the heat resistance was observed for 1000 hours at 80 ℃, bubbles or peeling was observed. It was left for 24 hours at room temperature immediately before evaluating the state of the specimen. In this case, bubbles are generated or peeled off at portions other than the edges, which are referred to as "bad", and bubbles are not generated or peeled off as "good". In addition, when it is impossible to attach, since evaluation itself is impossible, it was described as "evaluation impossible".

division Processing film Use plasma interval Processing speed Water contact angle reduction Adhesion performance evaluation Durability Evaluation after Attachment Example 9 TAC Example 2 0.5 mm 5 m / min 25 ° Good Good Example 10 TAC Example 6 1 mm 10 m / min 15 ° Good Good Example 11 COP Example 4 0.6 mm 25 m / min 22 ° Good Good Example 12 COP Example 5 0.5 mm 40 m / min 16 ° Good Good Example 13 COP Example 3 0.5 mm 6 m / min 36 ° Good Good Example 14 Acrylate film Example 5 3 mm 5 m / min 50 ° Good Good Example 15 Liquid crystal film1 Example 4 5 mm 1 m / min 14 ° Good Good Example 16 PC Example 1 2 mm 3 m / min 20 ° Good Good Comparative Example 5 COP Comparative Example 2 0.5 mm 3 m / min 3 ° Not attachable Not rated Comparative Example 6 PC Comparative Example 3 0.3 mm 10 m / min 0 ° Not attachable Not rated Comparative Example 7 Liquid Crystal Film 2 Comparative Example 4 2 mm 20 m / min 2 ° Not attachable Not rated Comparative Example 8 TAC Example 2 8 mm 10 m / min 4 ° Good Bad Comparative Example 9 COP Example 3 1 mm 0.2 m / min -° Film damage Comparative Example 10 COP Example 5 3 mm 55 m / min 0 ° Not attachable Poor rating

In Table 2, 'interval' refers to the distance between the plasma discharge surface and the film surface of the plasma apparatus, and 'processing speed' refers to the length (length along the processing direction) of the film to be processed per unit time. .

In Table 2, the degree of water contact angle reduction indicates how much the interface is activated. In other words, it indicates how much surface energy is increased. As the surface energy increases (as the degree of water contact angle decrease increases), the free surface is not formed. Since the tendency to contact an object is strong, adhesiveness increases. As can be seen from the table of Examples 9 to 16 that meet the conditions of the present invention, the water contact angle reduction was 14 ° to 50 °, but the Comparative Examples 5 to 7 did not satisfy the conditions of the invention. The contact angle reduction was less than 3 ° and the interface was hardly activated.

As a result, in Examples 9 to 16 manufactured according to the intervals and processing speeds specified in the present invention using the stable plasma in Table 1, it showed good adhesion characteristics and the laminate was separated even after a long time. While excellent adhesion durability was shown without problems, Comparative Examples 5 to 7 were unable to attach the film because the stability of the plasma is poor even if the interval and the treatment speed were adjusted within the range defined herein, and thus the durability evaluation was also performed. I could not. In particular, the COP film used in Examples 11 to 13 was very difficult to bond with other films due to the low degree of activation by the pretreatment method using a conventional alkaline solution, but excellent activity as a result of treatment by the method of the present invention It can be confirmed that it has a good adhesion performance.

Comparative Example 8 to Comparative Example 10, even in the case of using a stable plasma shows a result of poor durability if not treated by the interval and the treatment speed within the range specified herein, in particular, Comparative Example 9 using a COP film In this case, the film was damaged and even the durability measurement was impossible.

Adhesion performance with PSA

After the plasma treatment under the conditions shown in Table 3, after applying the commercial pressure-sensitive adhesive for polarizing plates on the plasma-treated surface of the film so as not to generate air bubbles, after passing 3 days at room temperature, the sample was cut into a size of 100 mm x 100 mm to obtain a sample. The reworkability and durability were evaluated. The evaluation method was as follows.

-Reworkability

The sample obtained above was attached to a glass substrate (200mm * 190mm * 0.7mm) in the clean room so that an air bubble or a foreign material might not generate | occur | produce at about 4 kg / cm <2> pressure, and the specimen was manufactured. When one side of the sample was cut out and peeled off by hand immediately after plywood and one day after plywood (24 hours), if any adhesive remained on the surface of the glass substrate, it was referred to as "bad". It was determined as "good".

- durability

The sample obtained above was attached to a glass substrate (200mm * 190mm * 0.7mm) in the clean room so that an air bubble or a foreign material might not generate | occur | produce at about 4 kg / cm <2> pressure, and the specimen was manufactured. In order to determine the heat and moisture resistance of the specimen, the specimen was left to stand at 60 ° C. and 90% relative humidity for 1,000 hours, and then visually observed whether bubbles or peeling occurred.

In addition, the heat resistance was observed after 80 ℃, 1,000 hours, bubbles or peeling. It was left for 24 hours at room temperature immediately before evaluating the state of the specimen. In this case, bubbles are generated or peeling occurs at portions except edges, and bubbles are not generated or bubbles are not generated.

division Processing film Plasma conditions interval Processing speed Water contact angle reduction Reworkability durability Example 17 TAC Example 1 3 mm 10 m / min 13 ° Good Good Example 18 TAC Example 5 0.5 mm 5 m / min 25 ° Good Good Example 19 COP Example 4 0.6 mm 20 m / min 26 ° Good Good Example 20 COP Example 6 2 mm 3 m / min 36 ° Good Good Example 21 COP Example 8 4 mm 1 m / min 10 ° Good Good Example 22 Acrylate film Example 2 1 mm 10 m / min 43 ° Good Good Example 23 Liquid crystal film 2 Example 4 2.5 mm 6 m / min 26 ° Good Good Example 24 PC Example 3 3 mm 5 m / min 16 ° Good Good Comparative Example 11 TAC Comparative Example 1 2 mm 6 m / min 2 ° Bad Good Comparative Example 12 COP Comparative Example 4 3 mm 5 m / min 0 ° Bad Bad Comparative Example 13 Acrylate film Comparative Example 3 0.5 mm 10 m / min 0 ° Bad Bad Comparative Example 14 TAC Example 2 7 mm 10 m / min 3 ° Bad Bad Comparative Example 15 COP Example 5 2 mm 55 m / min 0 ° Bad Bad

As can be seen from the table, the films of Examples 17 to 24 treated by the present invention showed good reworkability irrespective of their kind, and also showed excellent durability apart from the reworkability. However, Comparative Example 11, which did not satisfy the conditions of the present invention, although its durability was good, was very poor in reworkability, and Comparative Examples 12 to 15 were both poor in durability and reworkability.

Therefore, it was confirmed from the above examples that the plasma treatment method of the present invention is excellent.

The present invention not only provides a method of simply performing a film pretreatment process during a manufacturing process of a transparent optical film laminate, such as a polarizing plate laminate, a film for plasma display, a film for an organic EL display, and the like by using atmospheric pressure plasma, In addition, the transparent optical film laminate prepared after the pretreatment according to the present invention has not only superior adhesiveness than the conventional one, but also reworkability to detach and reattach the attached protective film. In particular, even in the case of the COP film, which was almost impossible to activate by the conventional pretreatment method, the present invention has excellent activity and thus can easily form a laminate.

Claims (22)

A method for pretreatment of a film, characterized by supplying oxygen radicals to the film surface using an atmospheric pressure plasma generator. The method of claim 1, wherein the main gas for plasma treatment uses helium, argon or nitrogen. The method of claim 2, wherein the operating frequency range is in the range of 1 kHz to 100 MHz. The method according to claim 3, wherein when the main gas is helium or argon, the operating frequency range is in the range of 1 MHz to 100 MHz. The method according to claim 3, wherein the operating frequency range is 1 kHz to 1 MHz when the main gas is nitrogen. The method according to claim 2, wherein the flow rate of the main gas is 1 to 50 standard liters per 1m ² (1 standard liter: 1 liter at 0 ° C and 1 atm). 7. The film pretreatment method according to any one of claims 1 to 6, wherein oxygen or dry air (CDA) is used as the reaction gas. The method according to claim 7, wherein the flow rate of the reaction gas is 1/1000 to 1/10 of the flow rate of the main gas. 8. The method of claim 7, wherein the spacing between the plasma discharge face and the film face to be treated is in the range of 0.1 mm to 10 mm. 10. The method of claim 9, wherein the spacing between the plasma discharge face and the film face to be treated is in the range of 0.5 mm to 5 mm. 8. The method according to claim 7, wherein the treatment speed of the film is in the range of 0.5 m / min to 50 m / min. A film supplying step of supplying a plurality of films; A pretreatment step of activating the adhesion surface of each film by supplying oxygen radicals generated from the atmospheric pressure plasma apparatus; An adhesive means supplying step of supplying an adhesive means between each film; And A pressing step of uniformly compressing the film interface supplied with the adhesive means by a pressing roll; Method for producing a film laminate, characterized in that consisting of. The method of claim 12, wherein the adhesive means is an adhesive or an adhesive. The method of claim 12, wherein the main gas for plasma treatment uses helium, argon or nitrogen. The method for producing a film laminate according to claim 14, wherein the operating frequency range is in the range of 1 kHz to 100 MHz. The method according to claim 15, wherein when the main gas is helium or argon, the operating frequency range is in the range of 1 MHz to 100 MHz. The method for manufacturing a film laminate according to claim 15, wherein when the main gas is nitrogen, the operating frequency range is 1 kHz to 1 MHz. The method of claim 12, wherein the reaction gas for plasma treatment is oxygen or dry air. The method according to any one of claims 12 to 18, wherein a distance between the plasma discharge surface and the film surface to be treated is in a range of 0.5 mm to 5 mm. A plurality of film supply means for supplying a film by rotating a film bundle wound in a roll; One or more atmospheric plasma apparatuses positioned behind the film supply path of the film supply means; Bonding means supply means positioned behind the film supply path of the plasma apparatus to supply means between each film; And A pressing roll for pressing each film stacking portion to sufficiently bond each interface supplied with the bonding means; Film laminate production equipment comprising a. 20. The film laminate production facility according to claim 19, further comprising a winding roll for winding the laminated film behind the pressing roll. 21. The film laminate production facility according to claim 20, wherein the adhesion means is an adhesive or an adhesive.

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