JP2007186594A - Coated film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coated film with excellent slipping property and low coefficient of friction, preventing winding dislocation, collapse of winding, etc., and capable of winding a roll by properly regulating winding hardness. <P>SOLUTION: The invention relates to the coated film in which a plurality of zonal organic coatings (C) are applied on one side (A) of a plastic film in longitudinal direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a coating film. In particular, the present invention provides a coating that can be exerted without losing the function of the coating agent by winding a film having a coated surface having a high friction coefficient and a low friction coefficient into a roll with a controlled appropriate winding hardness. Concerning the engineering film.

  A structure for forming an organic material layer on the surface of a plastic film is used in various fields by selecting an organic material suitable for each required performance and in the process or as a product. In particular, the release film provided with a silicone-based resin layer to provide release performance can be used in many fields, such as ceramic green sheets, adhesive / adhesive coated separate films, poultice separate films, and separate films for labels. used.

  These mold release films are required to be further improved in mold release properties as their uses expand (see Patent Documents 1 and 2). Usually, the coated surface of the silicone resin is provided with a release property as well as a slipperiness, resulting in a decrease in the friction coefficient, and the friction coefficient is lowered as the release property is enhanced.

  This phenomenon causes a flutter during running in the apparatus when the coated film is taken up in a roll shape, causing a laminating shift in the wound roll, and it becomes a winding scrap and becomes unwound. In some cases. The winding tension is increased as a measure to prevent this winding displacement and winding damage. However, in the case of a film with excellent slipperiness, for example, it is difficult to cut the tension with a nip roll or the like. Only the traveling tension and the winding tension are determined, and arbitrary tension control becomes difficult. Even if the fluttering in the traveling zone can be controlled to some extent, the winding portion slips and winds in the core direction.

  As a result, the winding hardness in the form of a roll is increased, and for example, it becomes a hard winding of 500 or more by echo chip hardness meter measurement. A roll wound up with high hardness causes various problems in its original functions such as releasability. For example, when the substrate PET thickness is 20 to 100 μm in a release film for poultice use, the fine base streaks at the time of PET film formation are emphasized by pressing with hard winding, and the streaky projections formed by lamination Becomes a streak-like defect on the peeled surface and causes partial heavy peeling due to the show-through of the coating resin, resulting in a poorly peeled state.

In addition, even when used for thin counts of 1 to 20 μm, etc. for ceramic green sheet applications, minute protrusions due to film additives etc. due to strong pressing at the time of release film roll may cause pinholes on the peeling surface or island-like This results in a serious defect in releasability, and a slight thickness unevenness of the film itself is emphasized to deteriorate the flatness of the green sheet itself. In order to prevent slipping, the coating thickness of the release resin may be reduced, or the friction coefficient may be increased by mixing other resins, but these are not preferable from the viewpoint of enhancing the peelability.
JP-A-8-276539 Japanese Patent No. 3687216

  The present invention, for example, in a coating film having a good sliding property and a low coefficient of friction, can prevent winding misalignment and the like, and can be wound into a roll by appropriately controlling the winding hardness. A working film is provided.

    This invention is a coating film which provided the some organic coating film (C) in the strip | belt shape in the longitudinal direction on the single side | surface (A) of the plastic film.

  According to the present invention, in a coating film having a low friction coefficient and rich in slipping, it is possible to eliminate defects due to winding tightening without considering countermeasures for defects at the time of winding. A film can be obtained.

  Furthermore, the coated film of the present invention suppresses the influence of thickness unevenness and unevenness of the base film to the minimum, and does not impair the intended function such as peelability.

  This invention is a coating film which provided the some organic coating film (C) in the strip | belt shape in the longitudinal direction on the single side | surface (A) of the plastic film.

  The plastic film of the coating film in the present invention includes a polyester film, an olefin film, a polycarbonate film, an acrylic film, a polyacid film, etc., but from the viewpoint of heat resistance, dimensional stability, hand surface properties, etc., the polyester film film Is most desirable.

  The polyester film is preferably made of a polyester film having an aromatic dicarboxylic acid as a main acid component and an alkylene glycol as a main diol component, and is preferably biaxially stretched. Specifically, for example, a biaxially stretched polyethylene terephthalate film is used. And a biaxially stretched polyethylene naphthalate film. In the present invention, as the polyester film preferably used, a polyester film produced by a conventionally known production method can be used, and the thickness of the polyester film is preferably 12 μm to 100 μm. The thickness is preferably 25 μm to 50 μm.

  The coated film of the present invention is provided with a plurality of organic coating films (C) in a strip shape in the longitudinal direction on one side (A) of a plastic film.

  In the present invention, the term “band-like” refers to a state in which coating layers having a constant width are arranged at regular intervals in the width direction and are continuously provided in the longitudinal direction.

  As the organic resin provided in a strip shape in the present invention, organic resins or inks generally used for printing and coating can be used, for example, acrylic resin, polyester resin, urethane resin, melamine resin, amide resin, vinyl chloride acetic acid. Examples thereof include vinyl copolymer resins, epoxy resins, and silicone resins. Polyester resins and acrylic resins are preferable in terms of performance. The organic resin may be colored with a pigment or a dye, and an antistatic agent or the like may be added. In order to adjust the friction coefficient, a particle component may be appropriately added.

  As a method for forming the organic resin layer (C), a coater or printing machine capable of forming a belt-like coat such as a gravure printing machine, a gravure coater and a die coater can be used.

  The thickness of the strip-shaped organic resin layer (C) is preferably 0.2 μm to 2.0 μm, more preferably 0.5 μm to 1.0 μm from the viewpoint of the friction coefficient. If the thickness is 0.2 μm or less, it may be difficult to reduce the winding hardness of the portion subjected to release, and if the thickness is 2.0 μm or more, the organic resin layer ( Problems such as wrinkling on the side of the portion provided with C) may occur. The band width is preferably 5 mm to 20 mm.

  The friction coefficient of the organic resin layer (C) in the band-shaped portion is preferably 0.5 or more in static friction coefficient (μs) and 0.3 or more in dynamic friction coefficient (μk). When the static friction coefficient (μs) is less than 0.5, it is difficult to adjust the winding hardness in the roll state, and winding may occur. Further, if the dynamic friction coefficient (μk) is less than 0.3, it is difficult to adjust the winding hardness in the roll state, and winding may occur.

  The coefficient of friction of the organic resin layer (C) of the belt-shaped coating portion can be adjusted by the coating resin component, coating thickness, etc. For example, when a melamine resin is used, the coating thickness is 0.2-2. A range of 0 μm is preferred.

  The coating film of the present invention is provided with a plurality of, ie, two or more organic coating films (C) in a strip shape in the longitudinal direction. The plurality of strip-like organic coating films (C) prevent winding due to fluttering and slipping during the running of the film. The strip-shaped organic coating film (C) may be applied to the entire surface of the film, but preferably two end portions are preferable. Since the strip-shaped organic coating film (C) is present at both ends of the film, it can be removed as necessary after the product is collected. The film may be commercialized as a transparent film, or may have printing on the surface. In this case as well, it is preferable that the strip-like organic coating film (C) is at both ends of the film.

  In the coated film of the present invention, the plastic film is preferably a biaxially stretched polyester film, and an organic coating film (D) is provided on the other surface (B).

  In the coated film of the present invention, more preferably, the static friction coefficient (μs) of the organic coating film (D) is 0.2 or less and the dynamic friction coefficient (μk) is 0.1 or less.

  Furthermore, in the coating film of this invention, More preferably, a silicone resin coating film is used as an organic coating film (D).

  Examples of the silicone resin preferably used in the present invention include addition reaction type, polycondensation reaction type, ultraviolet curable type and electron beam curable type silicone resins.

  Examples of the addition reaction type silicone resin include those obtained by heat-curing polydimethylsiloxane and hydrogensiloxane containing a vinyl group or hexenyl group under a platinum catalyst. As a specific example, Shin-Etsu Chemical ( KS774, KS776A, KS835, KS838, KS843, KS847H, KS3703, and the like manufactured by Toray Dow Corning Silicone Co., Ltd. Can be mentioned.

  As the polycondensation reaction silicone resin, those obtained by heat-curing polydimethylsiloxane containing a hydroxyl group at the terminal and hydrogen using an organic tin catalyst are suitably used. Specific examples include SRX290, SRX244, SYLOFF23 manufactured by Toray Dow Corning Silicone Co., Ltd., X62-470 manufactured by Shin-Etsu Chemical Co., Ltd., and KS723A / B.

  Examples of ultraviolet curable silicone resins include addition reaction type resins in which vinyl siloxane is hydroxylated in the presence of a platinum catalyst, such as X62-5039 and X62-5040 manufactured by Shin-Etsu Chemical Co., Ltd., and siloxanes containing alkenyl groups. And a radical addition type in which a siloxane containing a mercapto group is cured using a photopolymerization catalyst, such as BY24-510H manufactured by Toray Dow Corning Silicone Co., Ltd. Furthermore, examples of the cationic polymerization type resin in which an epoxy group-containing polydimethylsiloxane is photo-opened with an onium salt to be polymerized and cured include UV9300 and XS56-A2775 manufactured by Toshiba Silicone Co., Ltd.

  The method for forming the silicone resin layer on the polyester film is not particularly limited, and is a direct gravure coater, reverse gravure coater, reverse kiss coater, micro gravure coater, Meyer bar coater, die coater, lip coater and multistage reverse. Generally, a coating method such as a coater can be used. Among them, a micro gravure coater and a reverse kiss coater are preferably used because the uniformity of the coating thickness of the silicone resin is good and the occurrence of coating unevenness is small.

  In the present invention, when a silicone resin coating film is used as the organic coating film (D), the surface roughness of the silicone resin coating film is preferably free from protrusions having a height of 1 μm or more, and a ten-point average roughness (Rz). ) Is preferably 200 nm to 800 nm, and more preferably 300 nm to 500 nm. If the ten-point average roughness (Rz) exceeds 800 nm, a ceramic green sheet of 1 to 2 microns may cause pinholes. On the other hand, if the ten-point average roughness (Rz) is less than 200 nm, the friction coefficient increases, and the balance of slipperiness may be lost, resulting in poor handling of the film.

  Moreover, when a silicone resin coating film is used as the organic coating film (D), the center line average roughness (Ra) of the silicone resin coating film is preferably 10 nm to 30 nm. If the surface roughness is larger than 30 nm, it may cause defects such as pinholes when the green sheet is formed. When the center line average roughness (Ra) is less than 10 nm, the release films tend to block each other.

  When a silicone resin coating is used as the organic coating (D), the coating of the silicone resin layer is preferably 5 Kcps to 15 Kcps when the Si intensity after drying (Kα ray intensity) is measured by fluorescent X-rays. Preferably, it is 8 Kcps to 12 Kcps. The coating amount of the silicone resin layer is most preferably 10 Kcps when the Si intensity after drying (Kα ray intensity) is measured by fluorescent X-rays.

  If the Si strength is less than 5 Kcps, the releasability may be poor and the variation may increase. Conversely, if the Si strength exceeds 15 Kcps, the silicone migration may be deteriorated, or the roughness of the silicone surface may be rough and the lamination property may be reduced. There is.

  The application amount of the silicone resin layer is 10 Kcps when the Si strength (Kα ray intensity) after drying is measured by fluorescent X-rays, and the release performance is good, and the static friction coefficient at that time is 0.15. The coefficient of dynamic friction is 0.09.

  In order to improve the adhesion with the organic coating film (D), the plastic film used in the present invention may be subjected to corona treatment, plasma treatment or easy adhesion treatment in-line or offline.

  The coated film of the present invention can be wound into a roll. The roll state referred to in the present invention is a shape wound in a roll shape as the final product (for example, the shape described in FIG. 2). For example, a roll having a width of 250 mm and a winding length of 4000 m wound around a 3-inch core It refers to a roll having a width of 440 mm and a length of 8000 m.

  The winding hardness measured with an echo chip hardness tester when the coated film of the present invention is rolled is preferably 200 or more and 500 or less. The winding hardness is 500 or less, and the winding state is good without any deviation. In addition, when the tension cut is defective, winding tightening occurs, and the echo chip type indicates 700 or more.

  The coated film of the present invention can be effectively used as an adhesive surface separate film for the production of multilayer ceramic capacitors, cataplasm-coated products, various labels and the like.

  Next, although the coating film of this invention is demonstrated using an Example, this invention is not limited to these examples. In addition, evaluation of the coating film obtained by the following Example and comparative example was performed in accordance with the following method.

(1) Winding hardness:
Using an eco-chip hardness tester (impact D type) manufactured by Prosecek (PPOCEQ), 10 points in the width direction of a roll wound with a length of 4,000 m on a 3-inch core were measured.

(2) Si strength:
Using an X-ray fluorescence apparatus (RIX100 type) manufactured by Rigaku Denki Kogyo Co., Ltd., using a PR gas (argon 90%: methane 10%) as the detector gas, the intensity count of the Si element specific X-ray Kα ray of the coating film (Kcps) was measured.

(3) Surface roughness:
Ra, Rz at a moving speed of 0.5 mm / second and a roughness curve cutoff value of 0.25 mm (JIS B0601-1982) using a surface roughness measuring device (SE-30C type) manufactured by Kosaka Laboratory. Was measured.

(4) Peel strength:
Polyester adhesive tape (Nitto Denko Corporation 31B tape: thickness 25 μm) is reciprocated once with a 5 kg rubber roller on the surface to be released from the mold, and left at a temperature of 20 ° C. for 24 hours, and then 300 mm using a tensile tester. The resistance value when peeled 180 degrees per minute was measured.

(5) Ceramic sheet thickness:
Glass beads having a particle size of about 2 mm were added to a ceramic slurry having the following composition, mixed for 20 hours in a jet mill, dispersed, and then filtered to prepare a paste-like ceramic slurry. The obtained ceramic slurry was coated on a release film using a die coater to obtain a green sheet having a dry thickness of 4 μm.

Polyvinyl butyral (trade name BL-1 manufactured by Sekisui Chemical Co., Ltd.) 10 parts by weight Barium titanate (trade name HPBT-1 by Fuji Titanium Industry Co., Ltd.) 100 parts by weight Mixed solvent (toluene; ethanol, 1: 1) 100 parts by weight Part 5 parts by weight of dibutyl phthalate.

  The thickness of the obtained green sheet in the width direction was measured with a continuous thickness measuring machine and evaluated according to the following criteria.

○: Thickness variation is 0.1 μm or less in the range
Δ: Thickness variation is in the range of 0.1 to 0.2 μm
X: Thickness variation exceeds 0.2 μm in the range.

(6) Friction coefficient:
Using a device according to JIS K7125-1985, 12 μPET manufactured by Toray Industries, Inc. was mounted on the slider surface, and μs and μR were measured on the sample surface at a load of 100 g and a moving speed of 20 cm / min.

Example 1
Polyester film having a thickness of 38 μm and a width of 690 mm (trade name “Lumirror” (registered trademark) R65 manufactured by Toray Industries, Inc .; integrated average surface roughness Ra = 23 nm), butylated melamine resin (manufactured by Miha Laboratory) as an organic resin layer A paint prepared by adding a phosphite ester (plus coat DEP clear manufactured by Washin Chemical Industry Co., Ltd.) as a curing catalyst to a solvent and a gravure coat in a strip shape of 30 mm width at intervals of 300 mm is dried on a product name RP-50) The coated film was coated so as to have a coating thickness of 0.4 μm, and a coated film having a static friction coefficient (μs) of 0.61 and a static friction coefficient (μk) of 0.32.

  On the back surface of this polyester film, a silicone resin (BY24-846 manufactured by Toray Dow Corning Silicone Co., Ltd.) as an anchor layer was applied / dried with a reverse kiss coater so that the dry coating thickness was 0.02 μm. In addition, a coating solution of addition reaction type silicone resin (LTC750A manufactured by Toray Dow Corning Silicone Co., Ltd .; 100 parts by weight, curing agent SRX212; 1 part by weight) is dried at a Si intensity of X-ray fluorescence. A release film having a surface friction coefficient of 0.11 and a static friction coefficient (μk) of 0.08 was obtained by applying / drying with a reverse kiss coater so as to be 10 Kcps.

  Next, the obtained release film was slit at the center of the belt-like gravure coat portion, and a 330 mm-wide release film for forming a ceramic green sheet having a belt-like coat portion of 15 mm at both ends was obtained in a roll shape. The obtained evaluation results are shown in Table 1.

Example 2
In Example 1, instead of partially coating a butylated melamine resin as a band-shaped organic resin layer, 8 parts by weight of white ink (Panacia CVLSP / XS hardener manufactured by Dainippon Ink Industries, Ltd.) was applied with a coating thickness of 0.5 μm. A roll-shaped release film was obtained in the same manner as in Example 1 except that a belt-like print having a width of 20 mm was printed on the gravure printing machine. The obtained evaluation results are shown in Table 1.

Example 3
In Example 2, a roll-shaped release film was obtained in the same manner as in Example 2 except that the coating thickness of the white ink was 1.0 μm and the Si intensity of the fluorescent X-ray was 15 Kcps. The obtained evaluation results are shown in Table 1.

Comparative Example 1
An anchor layer (BY24-846 manufactured by Toray Dow Corning Silicone Co., Ltd.) is applied to one side of the polyester film without a band-shaped organic resin layer with a reverse kiss coater so that the dry coating thickness is 0.02 μm. / After drying, a coating solution of addition reaction type silicone resin (LTC750A manufactured by Toray Dow Corning Silicone Co., Ltd .; 100 parts by weight, curing agent SRX212; 1 part by weight) is dried and the coating thickness is fluorescent X A release film was obtained by applying / drying with a reverse kiss coater so that the Si intensity of the wire was 10 Kcps. The obtained release film was slit to obtain a release film for forming a ceramic green sheet having a width of 330 mm in a roll shape. The obtained evaluation results are shown in Table 1.

Comparative Example 2
In Example 1, a roll-shaped coating film was obtained in the same manner as in Example 1 except that only a 30 mm-wide strip-shaped coating part was provided at the center. The obtained evaluation results are shown in Table 1.

Claims (6)

  The coating film which provided the some organic coating film (C) in the strip | belt shape in the longitudinal direction on the single side | surface (A) of the plastic film.   The coated film according to claim 1, wherein the plastic film is a biaxially stretched polyester film and an organic coating film (D) is provided on the other surface (B).   The coated film according to claim 1 or 2, wherein the coating surface of the organic coating film (D) has a static friction coefficient of 0.2 or less and a dynamic friction coefficient of 0.1 or less.   The coated film according to any one of claims 1 to 3, wherein the belt-like coating portion of the organic coating film (C) has a static friction coefficient of 0.5 or more and a dynamic friction coefficient of 0.3 or more.   The organic coating (D) is a silicone resin coating, the surface roughness of the coated surface is 10-point average roughness (Rz), 800 nm or less / centerline average roughness (Ra) 30 nm or less. The coated film according to claim 1, wherein:   The coated film according to claim 1, wherein the winding hardness in a roll state is 200 or more and 500 or less.