KR102248716B1 - Release film and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a release film. More specifically, it has excellent smoothness, and is used for in-line coating used for electronic materials such as ceramic multilayer capacitors (MLCC), polarizer protection, and OCA release films and in-line films used for window films. It relates to a release film (In-Line Coating).

Description

Release film and its manufacturing method {RELEASE FILM AND MANUFACTURING METHOD THEREOF}

The present invention relates to a release film. In more detail, it relates to an in-line coating (In-Line Coating) release film applied to a window or electronic material.

Polyester film has excellent physical property stability and chemical resistance over a wide temperature range, and has good mechanical strength, surface properties, and uniformity of thickness, so it can be applied to various uses or process conditions. Accordingly, it is applied to capacitors, photographic films, labels, pressure-sensitive tapes, decorative laminates, transfer tapes, polarizing plates and green sheets for ceramic release, and the demand thereof is increasing in response to the recent high speed and automation trend.

Among them, silicone-coated release films are trending from off-line coating to in-line coating release films for cost reduction.

In the case of the inline coated release film due to the characteristics of the release coating layer, if the roughness is low, the air gap between the film and the film disappears and blocking occurs. Accordingly, process loss may occur, and release properties may change depending on the coating type. In the case of acrylic coating, the release coating layer and the acrylic coating layer react, causing a lock-up phenomenon, and when coating a polyurethane or an ester compound, there is a problem in that the post-curing of the release coating layer is not performed due to catalyst poison.

The present invention was conceived to solve the above problems, and the present invention has excellent smoothness, and is used for electronic materials such as ceramic multilayer capacitors (MLCC), polarizer protection, and OCA. It is an object of the present invention to provide an In-Line Coating release film used for release films and window films.

In addition, the present invention is to solve the non-uniformity of the release coating layer that occurs during coating by the in-line coating method, implements low surface roughness and transparency, and provides a release film that does not cause winding and fish eye.

In addition, the present invention has a good maximum acid height surface roughness (Rp) of 0.3 µm or less on one side of the film (surface A), preferably 0.1 µm to 0.3 µm, reducing the size of the defect, and having excellent processability. I want to provide a film.

In addition, the present invention is to provide a release film in which the polyester film is used as a base film, and a release coating layer is formed on one or both sides thereof, and the adhesion to the polyester film is excellent, and there is little change in release force over time. It is intended to provide a release film with little variation and high residual adhesion.

In addition, the present invention is to provide a thin-film release film with a thickness of the polyester base film of 10 to 75 μm, and accordingly, the coating thickness of the release layer is also 0.07 to 0.3 μm. It is intended to provide a release coating composition capable of coating and a method of manufacturing a release film using the same.

In order to achieve the above purpose,

In the present invention, a release coating layer is formed on one or both sides of a polyester base film, and the release coating layer comprises at least one or more components of the following formulas 1 and 2, a compound of formula 3, a platinum-based catalyst, and a second particle. It provides a release film containing.

Pa ≤ 0.6 (Equation 1)

Dmax ≤ 2.5 (Equation 2)

(In Equations 1 and 2, Pa is the average particle diameter (µm) of the particles, and Dmax refers to the maximum particle diameter (µm) of the particles.)

[Formula 1]

(In Formula 1, n, m, a and b are 3 to 100.)

[Formula 2]

(In Formula 2, n is 20 to 3000, m is 1 to 50, and a is 3 to 100.)

[Formula 3]

(In Chemical Formula 3, a is 1 to 150, b is 3 to 300, and a+b is 5 to 300.)

In addition, the present invention

a) melt-extruding the polyester resin to produce a sheet;

Pa ≤ 0.6 (Equation 1)

Dmax ≤ 2.5 (Equation 2)

(In Equations 1 and 2, Pa is the average particle diameter (µm) of the particles, and Dmax refers to the maximum particle diameter (µm) of the particles.)

b) stretching the sheet 3 to 5 times in the longitudinal direction at 80 to 150°C;

c) In-line coating method on one or both sides of the polyester base film uniaxially stretched in the longitudinal direction, including at least any one or more of the compounds of the following formulas 1 and 2, a compound of formula 3, a platinum-based catalyst, and a second particle Applying a release coating composition to;

d) drying and preheating the film to which the release coating composition is applied at 130 to 150° C., and then stretching the film to which the release coating composition is applied 3 to 4 times in the transverse direction to prepare a release film having a release coating layer; And

e) heat-treating;

It provides a method of manufacturing a release film comprising a.

[Formula 1]

(In Formula 1, n, m, a and b are 3 to 100.)

[Formula 2]

(In Formula 2, n is 20 to 3000, m is 1 to 50, and a is 3 to 100.)

[Formula 3]

(In Chemical Formula 3, a is 1 to 150, b is 3 to 300, and a+b is 5 to 300.)

The release film according to the present invention effectively controls the maximum particle diameter (Dmax) for the average particle diameter and particle size distribution of the particles on the base film and the release coating, thereby satisfying the surface characteristics that a release film for windows or electronic materials should have. At the same time, it has the advantage of realizing excellent smoothness. In addition, it is possible to effectively control the occurrence of pinholes by controlling the appropriate surface roughness to secure winding properties and workability, and reducing fish eyes.

In addition, the release film according to the present invention has a flat surface of the release layer, so that blocking does not occur even when wound in a roll shape, and is suitable for use as a window or an electronic material.

In addition, since the release film according to the present invention is coated by an in-line coating method, it is possible to reduce losses caused by post-processing, and to reduce the process, thereby maximizing economic efficiency and productivity due to cost reduction.

In addition, by forming a uniform coating layer, there is an advantage in that the releasing force changes over time and its variation is small, and the residual adhesion rate is 90% or more, so that excellent releasability can be realized.

1 is a graph showing the position of the maximum particle diameter in the present invention.

Hereinafter, each configuration of the present invention will be described in more detail.

The present invention relates to a release film for a low-illuminance, high-transparent electronic material or for a window.

In one aspect of the present invention, the base film is a polyester base film including a first particle that uses a polyester sole resin or satisfies the following formulas 1 and 2.

Pa ≤ 0.6 (Equation 1)

Dmax ≤ 2.0 (Equation 2)

(In Equations 1 and 2, Pa is the average particle diameter (µm) of the particles, and Dmax refers to the maximum particle diameter (µm) of the particles.)

In this case, the first particles may be added when synthesizing the polyester resin, or may be mixed in the melt extrusion step after synthesizing the polyester resin, but is not limited thereto. Preferably, the dispersibility of the particles is excellent, and in order to prevent agglomeration between particles, a slurry state, that is, particles and glycol are mixed and introduced during polymerization of the polyester resin.

In one aspect of the present invention, the average particle diameter of the first particles is 0.6 μm or less, preferably 0.15 to 0.6 μm. In addition, the maximum particle diameter of the first particle is 2.0 μm or less, preferably 0.6 to 2.0 μm. When the above range is satisfied, the surface smoothness of the polyester base film is excellent, and the surface is good.

When the maximum particle diameter of the first particle is more than 2.5 μm, the running property and winding property are excellent, but the probability of occurrence of defects when manufacturing the polyester base film increases because coarse particles are present, and it is wound up with a roll and stored for a long period of time. When the film surface looks uneven like an orange peel, an orange peel phenomenon may occur. This may cause coating unevenness in the post process, and may be transferred to the coated adhesive or the like to cause defects.

In the present invention, the maximum particle diameter (㎛) of the particles is measured using a particle size distribution analyzer. At this time, it means the size of the particles remaining just before the volume of the large particles reaches 0% on the particle size distribution graph.

1 is a graph showing the particle size distribution of mainly used inorganic particles. Dmax in FIG. 1 means the maximum particle diameter (µm).

In one aspect of the present invention, the content of the first particles is preferably 0.25% by weight or less based on the total weight of the film. If it is used in excess of 0.25% by weight, the maximum peak height surface roughness (Rp) increases, which increases the likelihood of occurrence of pinholes or fish-eye due to particle agglomeration.

In one aspect of the present invention, the difference in size between the average particle diameter and the maximum particle diameter of the first particles is not limited, but the smaller the difference in size is, the more uniform it is, so that excellent smoothness can be realized. Preferably, as can be seen from the particle size distribution graph, the narrower a graph containing a large amount of uniform particles, the more the maximum peak height surface roughness Rp is reduced, thereby suppressing the occurrence of pinholes. The first particle has the most excellent smoothness in the range of preferably 0.1 to 0.4, more preferably 0.2 to 0.38, in a correlation between the average particle diameter and the maximum particle diameter (Pa / Dmax).

In one aspect of the present invention, the method of including the first particles in the polyester base film is not limited, but when the polyester resin is synthesized, adding it in the form of a slurry dispersed in glycol is excellent in dispersibility and between particles. It is preferable because it can prevent agglomeration.

In one embodiment, the polyester may be obtained by condensation polymerization of an acidic component containing dicarboxylic acid as a main component and a glycol component containing alkyl glycol as a main component, and particles may be added in the condensation polymerization step or solid phase polymerization step, When the particles are added, it is preferable to add the particles in the form of a slurry dispersed in the glycol component.

In one aspect of the present invention, the polyester resin constituting the polyester base film may be a resin obtained by condensation polymerization of an acidic component containing a dicarboxylic acid as a main component and a glycol component containing an alkyl glycol as a main component. As the main component of the dicarboxylic acid, terephthalic acid or its alkyl esters or phenyl esters are mainly used, but some of them are, for example, isophthalic acid, oxyethoxy benzoic acid, adipic acid, sebacic acid, 5-sodium sulfoisophthalic acid, and the like. It can be used in place of a difunctional carboxylic acid or an ester-forming derivative thereof. In addition, ethylene glycol is the main target of the glycol component, but some of them are, for example, propylene glycol, trimethylene glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, and 1,4-bisoxyethoxy. Benzene, bisphenol, or polyoxyethylene glycol may be used instead, and if the content is small, a monofunctional compound or a trifunctional compound may be used in combination.

In one aspect of the present invention, the first particles are not particularly limited as long as the average particle diameter, addition amount, and size distribution are within the scope of the present invention, but preferably the average particle diameter is 0.15 to 0.6 μm, and the total weight of the film is The content is 0.25% by weight or less, and the maximum particle diameter (Dmax) in the particle size distribution is 0.6 to 2.0 μm, and coarse particles are preferably removed.

In one aspect of the present invention, the type of the first particle is not limited, and an inorganic particle, an organic particle, or a mixture of an inorganic particle and an organic particle may be used, and one type or a mixture of two or more types may be used. That is, it is possible to use one or two or more types of inorganic particles, one or two or more types of organic particles, or a mixture of one or two or more types of inorganic particles and one or two or more types of organic particles. Do.

As a specific example, the inorganic particles may be calcium carbonate, titanium oxide, silica, kaolin, barium sulfate, etc., and the organic particles may be silicone resin, crosslinked divinylbenzene polymethacrylate, crosslinked polymethacrylate, crosslinked polystyrene resin, Benzoguanamine-formaldehyde resin, benzoguanamine-melamine-formaldehyde resin, and melamine-formaldehyde resin may be used.

In one aspect of the present invention, the polyester base film may have a haze of 0.3 to 10%. When the haze of the film is less than 0.3%, transparency is excellent, but scratches are likely to occur during the film forming process, and roll pressing marks may occur in the MD stretching section, resulting in poor appearance. When the haze is more than 10%, the transparency is low, and there is a possibility that it may interfere with the inspection of defective parts such as pinholes and defects, which are usually performed in a film for electronic materials.

In one aspect of the present invention, the polyester base film has a maximum peak height surface roughness (Rp) of 0.1 ~ 0.3㎛.

At this time, the maximum peak height surface roughness (Rp) is based on JIS B0601, using a two-dimensional surface roughness meter (Kosaka Lab. Surfcorder SE-3300), a measurement speed of 0.05 mm/sec, a stylus radius of 2 μm, and a load of 0.7 mN. , The cutoff value is measured under the condition of 0.08mm, and the average value is calculated after measuring a total of five times by selecting a 1.5mm part of the reference length in the direction of the center line from the curve of the film cross section. At this time, the largest profile peak height from the center line within the sampling length is taken as the maximum peak height surface roughness (Rp).

If the maximum peak height surface roughness (Rp) is less than 0.1㎛, the haze of the film decreases, but there is a side effect of reducing the releasability by increasing the friction coefficient due to the small surface protrusion. If the maximum peak height surface roughness (Rp) is more than 0.3㎛, it is coarse Orange peel may occur when used as a release film for electronic materials due to the increase of surface protrusions due to particles, or it may be detected as a foreign substance during the final product inspection process. Accordingly, the polyester base film according to the present invention has a maximum peak height surface roughness (Rp) of 0.3 μm or less, and preferably, it is more preferable to have a maximum peak height surface roughness (Rp) of 0.15 to 0.27 μm.

In one aspect of the present invention, the polyester base film may have a static friction coefficient and a dynamic friction coefficient of 0.2 to 0.7. If the coefficient of static friction and coefficient of dynamic friction exceed 0.7, the winding property is poor, resulting in protrusions and scratches, and stable operation is impossible. If it is less than 0.2, the slip property of the film is increased, and there is a high possibility that the foam may come off.

The present invention is to improve the problem that the winding property is poor as the smoothness is improved by using a polyester base film having a low surface roughness, and fish-eye occurs or the coating layer is uneven when coating the release coating composition, The release coating composition includes at least any one or more components of the following compounds of Formulas 1 and 2, a compound of Formula 3, a platinum-based catalyst, and second particles.

[Formula 1]

(In Formula 1, n, m, a and b are 3 to 100.)

[Formula 2]

(In Formula 2, n is 20 to 3000, m is 1 to 50, and a is 3 to 100.)

[Formula 3]

(In Chemical Formula 3, a is 1 to 150, b is 3 to 300, and a+b is 5 to 300.)

Formulas 1 and 2 are in a prepolymer state as a subject of the release coating layer, and Formula 3 reacts with Formula 1 or 2 as curing. That is, the vinyl group of Formula 1 or 2 and the silane group of Formula 3 react. In Chemical Formula 3, since the silane group (Si-H) and Si-CH3 are randomly intersected, there is an advantage in that the reaction speed is increased due to lower steric hindrance than the curing agent in which only the silane group is continuous.

Commercialized examples of Formula 1 include EM490 from Wacker, 7920 and 7934 from Dow Corning, but are not limited thereto.

Commercialized examples of Formula 2 include Shin-Etsu's 3951, Wacker's D400E, and the like, but are not necessarily limited thereto.

Commercialized examples of Formula 3 include Wacker's V-72, V-15, and the like, but are not necessarily limited thereto.

The release coating layer is not limited, but includes at least one or more components selected from compounds of Formulas 1 and 2, a compound of Formula 3, a platinum-based catalyst, and a second particle, and a solid content of 10 to 30% by weight Phosphorus release coating composition may be formed by coating to a thickness of 0.07 ~ 0.3㎛.

If the solid content is less than 10% by weight, the polyester film surface cannot be sufficiently covered, resulting in deviation of the release force, and if it exceeds 30% by weight, the reaction conversion rate of the release coating layer cannot be supplied enough heat from the in-line coating. Can be lowered. In addition, when the coating thickness is less than 0.07 μm, the high peaks of the polyester film are not covered by the coating layer, so that the release force appears high, and when the coating thickness is more than 0.3 μm, the occurrence of coating stains and the reaction conversion rate of the release coating layer may be lowered.

Examples of the platinum-based catalyst commercialized include Wacker's EM440, but are not limited thereto.

The second particles are included to realize excellent transparency while lowering the surface roughness of the release coating layer. The type of the second particle is not limited, but an inorganic particle, an organic particle, or a mixture of inorganic particles and organic particles may be used, and one type or a mixture of two or more types may be used. That is, it is possible to use one or two or more types of inorganic particles, one or two or more types of organic particles, or a mixture of one or two or more types of inorganic particles and one or two or more types of organic particles. Do.

When the second particle is an inorganic particle, any one or two or more selected from the group consisting of silica, alumina, zirconia, and titania may be used. The average particle diameter of the second particles is not limited, but a coating layer suitable for use as a release film can be formed in a range of 10 to 1500 nm, more preferably 50 to 800 nm, and a coating layer is formed by an in-line coating method. It is desirable because it can.

The second particles are preferably contained in 0.1 to 10% by weight, more preferably 0.1 to 5% by weight in the coating layer. If the content of particles is less than 0.1% by weight, the surface roughness is very low, and there may be a problem of poor winding and blocking. If it exceeds 10% by weight, the haze may rapidly increase or particle agglomeration may occur, and the release force may increase. Causes.

In the present invention, more preferably, when organic particles are used, the second particles have a small haze change rate, particle agglomeration does not occur, and silicon reaction is not affected.

The second particles preferably satisfying the following Equations 3 and 4 can prevent blocking that may occur between the film and the film, and can implement excellent transparency.

0.01 ≤ Pa ≤ 1.5 (Equation 3)

0.03 ≤ Dmax ≤ 2.0 (Equation 4)

(In Equations 3 and 4, Pa is the average particle diameter (µm) of the particles, and Dmax refers to the maximum particle diameter (µm) of the particles.)

In the release coating layer of the present invention, the content of the second particles is not limited, but it may be preferably 0.01 to 10% by weight, more preferably 0.1 to 0.5% by weight in the release coating layer.

In the present invention, the release coating layer may further include any one or more components selected from alcohol-based solvents, wetting agents, and slip agents.

The alcohol-based solvent can be used to increase wettability and apply uniformly. In one embodiment, a quick-drying solvent having good volatility, such as isopropyl alcohol, N-propanol, ethyl cellulose, methyl cellulose, and butyl cellulose, may be used, but is not limited thereto. In another aspect, water may be used in place of the alcohol-based solvent. It is preferable to use 0.1 to 10% by weight of the alcohol-based solvent in the release coating composition, and if it is less than 0.1%, the effect is insignificant, and if it is more than 10%, the problem of appearance staining occurs due to too fast drying speed. Occurs.

The wetting agent is used to evenly apply the emulsion on the polyester film, and any one or more selected from the group consisting of polyethylene glycol, polyethylene ester, modified silicone, fluorine-based compound, and the like may be used. The wetting agent is not limited, but a silicone-based wetting agent is preferable. Examples of commercialized silicone-based wetting agents include Dow Corning's Q2-5212 and TEGO's Wet-250, but are not necessarily limited thereto.

The content of the wetting agent is preferably 0.1 to 1.0% by weight, and if it is less than 0.1%, the effect is insignificant, and if it is 1.0% or more, there is a possibility of transfer to an adhesive used in post processing.

In one embodiment, in the release coating composition, the solid content of at least one or more components selected from the compounds of Formulas 1 and 2 may be 5 to 25% by weight, more specifically 8 to 16% by weight. If it is less than 5% by weight, the film surface cannot be sufficiently covered, and if it is more than 25% by weight, the reaction conversion rate is low and the residual adhesion rate may increase.

The solid content of the compound of Formula 3 may be 0.5 to 5% by weight, more specifically 0.8 to 2% by weight. If it is less than 0.5% by weight, the release coating layer cannot be sufficiently hardened, and if it is more than 5% by weight, unreacted Silane Group remains, and the change over time of the release force can be increased. The platinum-based catalyst may have a solid content of 0.001 to 3% by weight, more specifically 0.005 to 0.1% by weight. If it is less than 0.001% by weight, the effect is insignificant, and if it is more than 3% by weight, the Pt catalyst remains excessive, which may cause uneven release force. The solid content of the wetting agent may be 0.1 to 3% by weight, more specifically 0.5 to 2% by weight. If it is less than 0.1% by weight, the effect is insignificant, and if it is more than 3% by weight, coating unevenness may occur.

The release film according to the present invention is maintained at 70° C. for 24 hours while the adhesive tape is adhered, the adhesive tape is removed, and after laminating on a Teflon sheet, the residual adhesive rate calculated according to Equation 6 below is 90% or more. Can be.

Residual adhesion rate = adhesion of adhesive tape after aging at 70℃ for 24 hours / adhesion of initial adhesive tape × 100 (Equation 5)

It can be determined that the unreacted material of the release film is low in the range of the residual adhesion rate of 90% or more, and the amount of the unreacted material of the release film transferred to the final product after post-processing by the customer is small, so it is preferable.

In order to obtain the polyester film as described above, the method for producing a polyester film according to an aspect of the present invention is

a) manufacturing a sheet by melt-extruding a polyester resin containing first particles satisfying the following formulas 1 and 2;

0.15 ≤ Pa ≤ 0.6 (Equation 1)

0.6 ≤ Dmax ≤ 2.5 (Equation 2)

(In Equations 1 to 3, Pa is the average particle diameter (µm) of the particles, and Dmax refers to the maximum particle diameter (µm) of the particles.)

b) stretching the sheet 3 to 5 times in the longitudinal direction at 80 to 150°C;

c) In-line coating method on one or both sides of the polyester base film uniaxially stretched in the longitudinal direction, including at least any one or more of the compounds of the following formulas 1 and 2, a compound of formula 3, a platinum-based catalyst, and a second particle Applying a release coating composition to;

d) drying and preheating the film to which the release coating composition is applied at 130 to 150° C., and then stretching the film to which the release coating composition is applied 3 to 4 times in the transverse direction to prepare a release film having a release coating layer; And

e) heat-treating; includes.

In the manufacturing method of the present invention, when applying the release coating composition in step c), it may be applied using a gravure roll.

The coating method is not limited, but it is preferable to use a gravure coating roll because the release coating composition can be applied to a uniform thickness.

In step d), if the temperature is less than 130°C, the film may break, and if it exceeds 155°C, the uniformity of the film thickness may decrease. In addition, when the stretch ratio is less than 3 times, the film thickness uniformity may be deteriorated, and when it is more than 4 times, the film may break.

In step e), the heat treatment may be performed at 230 to 250°C. Below 230℃, the release coating layer is not sufficiently reacted, so that it may be pushed, and if it exceeds 250℃, heat wrinkles and orange peel of the film may occur.

The release film may have a thickness of a polyester base film of 10 to 75 μm, and a thickness of a release coating layer of 0.07 to 0.3 μm.

Hereinafter, for a more specific description of the present invention, an example is given and the present invention is not limited to the following examples.

1) Measurement of average particle diameter and maximum particle diameter (Dmax) of particles:

The average particle diameter and the maximum particle diameter (Dmax) were measured using a particle size distribution analyzer (Beckman-Colter, LS13 320). The size of the remaining particles on the particle size graph just before the volume of large particles reaches 0% is called the maximum particle diameter (Dmax). Fig. 1 shows a graph for the particle size distribution.

2) Haze measurement:

The measurement method was measured based on ASTM D-1003, and after randomly extracting 7 parts of the polyester film from 2 edges and 1 center, cut into 5cm × 5cm sizes, and a haze meter (Nippon Denshoku NDH 300A) Into the 555nm wavelength light was transmitted and calculated by the following equation, and then the average value excluding the maximum/minimum value was calculated.

Haze (%) = (Total scattered light/Total transmitted light) × 100

3) Measurement of surface roughness (Ra) and maximum peak height (Rp):

Based on JIS B0601, a two-dimensional surface roughness meter (Kosaka Lab. Surfcorder SE-3300) was used to measure under the conditions of a measurement speed of 0.05 mm/sec, a stylus radius of 2 μm, a load of 0.7 mN, and a cutoff value of 0.08 mm. The average value was calculated after selecting the 1.5mm part of the reference length in the direction of the center line from the curve of, and calculating the average value, with the center line as the x-axis and the vertical direction as the y-axis, and the roughness curve as y=f(x). When shown, it was calculated by the following equation.

(L: 측정길이)

(L: measurement length)

At this time, the largest profile peak height from the center line within the sampling length was taken as the maximum peak height surface roughness (Rp).

4) Coating uniformity measurement

In the polyester release film, if the area of the part where the release layer is not formed relative to the base film area is 1% or less, it is marked as good, and if it exceeds 1%, it is marked as defective.

5) Coating thickness measurement

After measuring the silicon content of the release layer with a calibrated XRF equipment (Oxford's LX3500), it is converted into the coating thickness and marked.

6) Measurement of release force (Standard Tape: TESA 7475)

A sample was prepared by placing the tape on the release coating layer and rubbing it reciprocating twice using a 2Kg rubber roll, and then cutting it into a size of 50mm×15cm. The prepared sample was subjected to a load of 70 g/cm 2 and left at 55° C. for 24 hours, and then Peel peeling evaluation at 180° was performed using a Peel Tester (Chem Instrument, AR-1000).

The peeling rate was measured 5 times at 300mm/min, and the average value was indicated.

7) Measurement of change over time of release force

A sample was prepared by placing the tape on the release coating layer and rubbing it reciprocating twice using a 2Kg rubber roll, and then cutting it into a size of 50mm×15cm. The prepared sample was subjected to a load of 70g/cm2 and allowed to stand at 55° C. for 240 hours, and then Peel peeling evaluation at 180° was performed using a Peel Tester (Chem Instrument, AR-1000).

The peeling rate was measured 5 times at 300mm/min, and the average value was indicated.

Average of change over time of release force: This is the average value obtained by continuously measuring the 10cm range.

Variance of change over time of release force: It shows the difference between the maximum and minimum values while continuously measuring the 10cm range.

8) residual adhesion rate

This is a method for confirming the transfer of the silicone release film to the adhesive after the adhesive is laminated. After the release film is laminated to the adhesive to induce the transfer under severe conditions, the adhesive strength of the adhesive laminated to the Teflon is compared and evaluated in the same manner.

In general, a residual adhesion rate of 90% or more is required.

In the following examples and comparative examples, the following was used as the particle and coating composition solution.

Particle A: Calcium carbonate particles having an average particle diameter of 0.59 µm and a maximum particle diameter (µm) of 2.2 µm

Particle B: Titanium dioxide particles having an average particle diameter of 0.36 µm and a maximum particle diameter (µm) of 1.52 µm

Particle C: Calcium carbonate particles having an average particle diameter of 0.51 µm and a maximum particle diameter (µm) of 2.42 µm

Particle D: Silica particles with an average particle diameter of 0.19 μm and a maximum particle diameter (μm) of 0.6 μm

Coating Solution 1: Polydimethylsiloxane of Formula 1 (Dow Corning) 7920 as a solid content of 49.99% by weight, a platinum catalyst (Wacker, EM440) as a solid content of 0.01% by weight, a composition having a total solids content of 50% by weight.

Coating Solution 2: Polydimethylsiloxane of Formula 2 (Shin-Etsu Company 3851) as a solid content of 49.99% by weight, a platinum catalyst (Wacker, EM440) as a solid content of 0.01% by weight, a composition having a total solid content of 50% by weight.

Coating solution 3: A composition containing 50% by weight of a hydrogen silane compound of Formula 3 (Wacker, V-15) in solid content.

Coating solution 4: A composition containing 80% by weight of a solid content with a silicone-based Wetting Agent (Dow Corning, Q2-5212).

[Example 1]

20% by weight of the coating solution 1 and 1.1% by weight of the coating solution 2, 1.0% by weight of the coating solution 3, _{0.15% by weight of 80nm silica (SiO 2} ) particles and 0.05% by weight of 800nm silica particles are mixed so that the total solid content is 22.3% by weight. Water was added to prepare coating solution A.

1000 g of dimethyl terephthalate, 576 g of ethylene glycol, 300 ppm of magnesium acetate and 400 ppm of trimethyl phosphate compared to the polyester resin content were put into a reactor, and the transesterification reaction was carried out while distilling methanol. After the transesterification reaction was completed, calcium carbonate particles A as shown in Table 1 were added as ethylene glycol sludge (mixed with 50% by weight of calcium carbonate and 50% by weight of ethylene glycol) in an amount of 1.0 parts by weight based on 100 parts by weight of the polyester resin. I did. Thereafter, a polycondensation reaction was carried out at 285° C. and 0.3 torr vacuum to obtain a polyester chip having an intrinsic viscosity of 0.61.

The polyester chip was melt-extruded at 280°C and then quenched to 24°C using a large roll to obtain a polyester sheet. The obtained polyester sheet was stretched in a longitudinal direction of 3.5 times at 110° C., and a coating solution (A) was applied to the cooled film using a ceramic gravure coater.

After drying and preheating at 150° C., it was stretched four times in the transverse direction to prepare a biaxially stretched film. The obtained biaxially stretched film was heat-treated at 240° C. to obtain a polyester film having a thickness of 25 μm.

The physical properties of the obtained polyester film were measured and shown in Table 1 below.

[Examples 2 and 3]

The experiment was the same as the method of Example 1, but a polyester film was prepared by varying the type and content of the particles as shown in Table 1 below.

The physical properties of the obtained polyester film were measured and shown in Table 1 below.

[Example 4]

It was carried out in the same manner as in Example 1, except that particle D was used in the base film, and the content in the film was as shown in Table 1 below, and silica particles having an average particle diameter of 0.2 μm were added in the coating solution A.

The physical properties of the obtained polyester film were measured and shown in Table 1 below.

[Example 5]

It was carried out in the same manner as in Example 1, except that a polyester film containing no particles was used as the base film.

The physical properties of the obtained polyester film were measured and shown in Table 1 below.

[Example 6]

Except for using a mixture of particles A and B, the coating thickness was changed as shown in Table 1 below, and the same method as in Example 4 was carried out.

The physical properties of the obtained polyester film were measured and shown in Table 1 below.

[Comparative Example 1]

It was carried out in the same manner as in Example 5, except that the coating solution A was used that does not contain silica particles.

The physical properties of the obtained polyester film were measured and shown in Table 1 below.

[Comparative Example 2]

It was carried out in the same manner as in Example 5, except that the coating solution A was used that does not contain silica particles.

The physical properties of the obtained polyester film were measured and shown in Table 1 below.

[Table 1]

Claims (20)

A release coating layer is formed on one or both sides of the polyester base film,
The release coating layer is a release film comprising at least one or more components of the following formulas 1 and 2, a compound of formula 3, a platinum-based catalyst, and second particles satisfying the following formulas 3 and 4:
[Formula 1]

(In Formula 1, n, m, a and b are 3 to 100.)
[Formula 2]

(In Formula 2, n is 20 to 3000, m is 1 to 50, and a is 3 to 100.)
[Formula 3]

(In Chemical Formula 3, a is 1 to 150, b is 3 to 300, and a+b is 5 to 300.)
0.01 ≤ Pa ≤ 1.5 (Equation 3)
0.03 ≤ Dmax ≤ 2.0 (Equation 4)
(In Equations 3 and 4, Pa is the average particle diameter (µm) of the particles, and Dmax refers to the maximum particle diameter (µm) of the particles.) The method of claim 1,
The polyester base film is a release film comprising first particles satisfying the following formulas 1 and 2.
Pa ≤ 0.6 (Equation 1)
Dmax ≤ 2.5 (Equation 2)
(In Equations 1 and 2, Pa is the average particle diameter (µm) of the particles, and Dmax refers to the maximum particle diameter (µm) of the particles.) delete The method of claim 1,
The release coating layer is a release film further comprising any one or more components selected from an alcohol-based solvent, a wetting agent and a slip agent. The method of claim 2,
The release coating layer is a release film having a dry coating thickness of 0.07 ~ 0.3㎛. The method of claim 2,
The first and second particles are inorganic particles, organic particles, or a mixture of inorganic particles and organic particles, and one or two or more types are mixed. The method of claim 1,
The content of the second particles is 0.1 to 10% by weight in the release coating layer release film The method of claim 2,
The content of the first particles is 0.25% by weight or less of the total weight of the release film. The method of claim 6,
The inorganic particles are at least one selected from the group consisting of calcium carbonate, alumina, titania, silica, barium sulfate, mica, and kaolin, and the organic particles are silicone resin, crosslinked divinylbenzene polymethacrylate, crosslinked polymethacrylic Rate, cross-linked polystyrene resin, benzoguanamine-formaldehyde resin, benzoguanamine-melamine-formaldehyde resin, and melamine-formaldehyde resin, any one or more selected from the group consisting of a release film. The method of claim 1,
The polyester base film is a release film having a maximum peak height surface roughness (Rp) of 0.1 ~ 0.3㎛. The method of claim 1,
The polyester base film is a release film having a haze of 0.3 to 10%. The method of claim 1,
The polyester base film is a release film having a thickness of 10 ~ 75㎛. The method of claim 1,
The release film is a release film having a residual adhesion rate of 90% or more calculated according to Equation 6 below after the release film is maintained at 70° C. for 24 hours while the adhesive tape is adhered, the adhesive tape is removed, and laminated on a Teflon sheet.
Residual adhesion rate = adhesion of adhesive tape after aging at 70℃ for 24 hours / adhesion of initial adhesive tape × 100 (Equation 5) The method of claim 1,
The release coating layer is a release film formed by applying the in-line coating method. a) melt-extruding a polyester resin to produce a sheet,
b) stretching the sheet 3 to 5 times in the longitudinal direction at 80 to 150°C;
c) In-line coating method on one or both sides of the polyester base film uniaxially stretched in the longitudinal direction, at least any one or more of the compounds of the following formulas 1 and 2, the compound of formula 3 and the platinum-based catalyst, and the following formulas 3 and 4 Applying a release coating composition comprising the second particles satisfying;
d) drying and preheating the film to which the release coating composition is applied at 130 to 150° C., and then stretching the film to which the release coating composition is applied 3 to 4 times in the transverse direction to prepare a release film having a release coating layer; And
e) heat-treating;
Manufacturing method of a release film comprising:
[Formula 1]

(In Formula 1, n, m, a and b are 3 to 100.)
[Formula 2]

(In Formula 2, n is 20 to 3000, m is 1 to 50, and a is 3 to 100.)
[Formula 3]

(In Chemical Formula 3, a is 1 to 150, b is 3 to 300, and a+b is 5 to 300.)
0.01 ≤ Pa ≤ 1.5 (Equation 3)
0.03 ≤ Dmax ≤ 2.0 (Equation 4)
(In Equations 3 and 4, Pa is the average particle diameter (µm) of the particles, and Dmax refers to the maximum particle diameter (µm) of the particles.) The method of claim 15,
The step of preparing the sheet is a method of producing a release film by melt-extruding a polyester resin containing first particles satisfying the following Equations 1 and 2.
0.15 ≤ Pa ≤ 0.6 (Equation 1)
0.6 ≤ Dmax ≤ 2.5 (Equation 2)
(In Equations 1 to 3, Pa is the average particle diameter (µm) of the particles, and Dmax refers to the maximum particle diameter (µm) of the particles.) delete The method of claim 15,
When the release coating composition is applied in step c), a method for producing a release film is applied using a gravure roll. The method of claim 15,
The release film is a method of manufacturing a release film having a thickness of a polyester base film of 10 to 75 μm and a dry coating thickness of a release coating layer of 0.07 to 0.3 μm. The method of claim 15,
In the step e), the heat treatment is carried out at 230 ~ 250 ℃ method for producing a release film.

Images