JP2013116620A - Release film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a release film that can strike a balance between embeddablity to a circuit exposure film and releasability after heating press, in the heating press when producing a circuit board.SOLUTION: A release film 10 has a cushion layer 20 and a release layer 1. The cushion layer has a first resin layer 2 and a second resin layer 3, and in the release film, a vicat softening point X (°C) of the first resin layer and a vicat softening point Y (°C) of the second resin layer are different. The release film can strike a balance between the embedding property to the circuit exposure film, and the mold releasability after the press of pressurizing in the heating press in producing the circuit board by taking the above configuration.

Description

  The present invention relates to a release film.

  JP 2008-105319 A proposes a multilayer release film composed of a cushion layer and a release layer. Such a release film is obtained, for example, by adhering a coverlay film (hereinafter referred to as “CL film”) to a flexible film (hereinafter referred to as “circuit exposed film”) from which a circuit is exposed through an adhesive. And used as a release film for producing a flexible printed circuit board (hereinafter referred to as “FPC”).

JP 2008-105319 A

The release film as described in Patent Document 1 makes the cushion layer rigid in order to improve the releasability, so that the embedding property to the circuit exposed film becomes insufficient, and the CL film adhesive In some cases, exudation becomes large, and defects such as yield decrease occur.

An object of the present invention is to provide a release film capable of achieving both embedding in a circuit-exposed film and release property after the heat press in a heat press for producing a circuit board.

Such an object is achieved by the present inventions (1) to (12) below.
(1) A release film having a cushion layer and a release layer, wherein the cushion layer has a first resin layer and a second resin layer, and the Vicat softening point X of the first resin layer A release film, wherein (° C.) is different from the Vicat softening point Y (° C.) of the second resin layer.
(2) The release film according to (1), wherein the Vicat softening point X (° C.) of the first resin layer and the Vicat softening point Y (° C.) of the second resin layer satisfy X <Y.
(3) The Vicat softening point X (° C.) of the first resin layer and the Vicat softening point Y (° C.) of the second resin layer satisfy YX> 50 (1) or (2) Release film.
(4) The release film according to any one of (1) to (3), wherein the Vicat softening point X (° C.) of the first resin layer is 80 or more.
(5) The release film according to any one of (1) to (4), wherein the thickness of the second resin layer is 5% or more and 50% or less of the entire release film.
(6) The release film according to any one of (1) to (5), wherein the second resin layer includes one or more resins made of a group of polypropylene, polyester, polyamide, and polyether.
(7) The release film according to any one of (1) to (6), wherein the cushion layer includes two first resin layers.
(8) The release film according to any one of (1) to (7), wherein the release layer contains any one of polyolefin, polyester, and polystyrene as a main component.
(9) The release film according to (8), wherein the polyolefin contained in the release layer is 1.4 methylpentene.
(10) The release film according to (8) or (9), wherein the polyester contained in the release layer is polybutylene terephthalate.
(11) The release film according to any one of (8) to (10), wherein the polystyrene contained in the release layer is syndiotactic polystyrene. (12) The first release layer, the cushion layer, and the second. The release film according to any one of (7) to (11), wherein the release layer has a release film in this order, and the cushion layer has the first resin layer on both surfaces of the second resin layer. Mold film.

  According to the present invention, it is possible to provide a release film having both embedding property and release property.

It is a longitudinal cross-sectional view of the release film which concerns on 1st Embodiment of this invention. It is a figure which shows an example of the manufacturing apparatus of the release film which concerns on embodiment of this invention. It is a longitudinal cross-sectional view of the release film which concerns on 2nd Embodiment of this invention. It is a longitudinal cross-sectional view of the release film which concerns on 3rd Embodiment of this invention. It is a figure which shows an example of the usage method of the release film which concerns on embodiment of this invention. It is a figure which shows an example of the heating pattern of a heating press when using a release film which concerns on embodiment of this invention, and making CL film closely_contact | adhere to the uneven | corrugated | grooved part of a circuit pattern.

  Hereinafter, the release film of the present invention will be described in detail based on specific embodiments.

  The release film of the present invention is a release film having a cushion layer and a release layer, and the cushion layer has a first resin layer and a second resin layer, and the first resin layer. The release film is characterized in that the Vicat softening point X (° C.) and the Vicat softening point Y (° C.) of the second resin layer are different.

  The mold release film of the present invention can achieve both embedding in a circuit exposed film and mold release after pressure pressing in a heat press for producing a circuit board by adopting the above-described configuration. A release film can be provided, and in addition, generation of wrinkles during film formation can be suppressed, and a release film having excellent heat resistance can be provided.

<First Embodiment>
First, 1st Embodiment of the release film of this invention is described.

  As shown in FIG. 1, the release film 10 of 1st Embodiment is laminated | stacked in this order on the 1st release layer 1, and the cushion layer 20 which has the 1st resin layer 2 and the 2nd resin layer 3. As shown in FIG. Yes. In the following description, for convenience of explanation, the upper side of FIG. 1 is referred to as “upper” and the lower side is referred to as “lower”.

1. Cushion layer The cushion layer 20 of the first embodiment includes a first resin layer 2 and a second resin layer 3. Here, the Vicat softening point X (° C.) of the first resin layer 2 and the Vicat softening point Y (° C.) of the second resin layer 3 need to be different. When X and Y are different, it is possible to achieve both embedding in a circuit-exposed film and releasability after pressure pressing in a heating press when manufacturing a circuit board.

  Moreover, it is preferable that the Vicat softening point X (° C.) of the first resin layer 2 and the Vicat softening point Y (° C.) of the second resin layer 3 satisfy X <Y. With the above-described configuration, in the heat press for producing the circuit board, the embedding property in the circuit exposed film and the releasability after the pressure press are further improved, and the wrinkle at the time of forming the film is improved. Can be suppressed.

  Further, the Vicat softening point X (° C.) of the first resin layer 2 and the Vicat softening point Y (° C.) of the second resin layer 3 preferably satisfy YX> 50, and satisfy YX> 80. More preferably. With the above-described configuration, the embedding property in the circuit exposure film and the releasability after the pressure press can be further improved in the heating press when producing the circuit board. Generation of wrinkles during molding can be suppressed.

  The first resin layer 2 preferably has a Vicat softening point X (° C.) of 80 or more, more preferably 100 or more and 140 or less. When X exceeds the said lower limit, heat resistance, moldability, and mold release property can be improved while maintaining embeddability in the circuit exposed film. In addition, by being below the upper limit, the resin oozes from the end face of the release film during pressing while exhibiting sufficient embedding properties, and adheres to the press hot platen, etc., and secondary contamination occurs in the next process Can be suppressed.

Moreover, the 1st resin layer 2 is although it does not specifically limit, It is preferable that a thermoplastic resin is included. Examples thereof include polyethylene resins, ethylene copolymer resins such as ethylene-methyl methacrylate (hereinafter referred to as EMMA), ethylene vinyl acetate (hereinafter referred to as EVA), and two or more of these may be mixed. By including these, the embedding property to a circuit exposure film can be improved, maintaining the heat resistance and handling property of a release film.

  The second resin layer 3 preferably has a Vicat softening point Y (° C.) of 130 or more and 250 or less, more preferably 150 or more and 230 or less. When Y is within the above range, the handling property, heat resistance, and wrinkle resistance can be improved while maintaining the embedding property in the circuit exposed film, and the mold release property after press pressing is further improved. Can be improved. Moreover, when the said upper limit is exceeded, the film forming property of a release film will fall.

Moreover, the 2nd resin layer 3 is although it does not specifically limit, It is preferable that a thermoplastic resin is included. For example, it is preferable to include one or more resins consisting of the group of polypropylene, polyester, polyamide and polyether, and two or more of these may be mixed. By including these, handling property, heat resistance, and wrinkle resistance can be improved while maintaining embeddability in the circuit exposed film. In addition, the releasability after pressure pressing can be further improved.

Moreover, it is preferable that the 2nd resin layer 3 is 5% or more and 50% or less by the ratio of the thickness in the release film 10. By being in the said range, the mold release property after a press press can further be improved.

An adhesive resin may be interposed between the first resin layer 2 and the second resin layer 3 in the cushion layer 20, but it is preferable that there is little bleeding of the film end face.

2. Release Layer The first release layer 1 is formed from a resin having good release properties with respect to a circuit exposed film or the like (hereinafter referred to as “release layer forming resin”). As such a release layer forming resin, for example, polyolefin, polyester, and polystyrene are preferable, and the release property after pressure pressing can be further improved. Furthermore, as a polyolefin, a resin mainly composed of poly (4-methyl-1-pentene) (hereinafter referred to as “TPX (registered trademark) resin”), a polystyrene-based resin having a syndiotactic structure as polystyrene (hereinafter referred to as “hereinafter referred to as“ TPX (registered trademark) resin ”). Resin whose main component is "SPS resin", a resin whose main component is a polybutylene terephthalate resin as a polyester, and a resin whose main component is a polyetherester block copolymer.

(1) Resin mainly composed of TPX resin The resin mainly composed of TPX resin preferably contains 90% by weight or more of TPX resin, and more preferably contains 95% by weight or more. Note that the release layer 210 may be formed of only TPX resin. TPX resin is commercially available from Mitsui Chemicals, Inc. under the trade name TPX (registered trademark).

(2) Resin mainly composed of SPS resin Resin mainly composed of SPS resin is commercially available from Idemitsu Kosan Co., Ltd. under the trade name Zalek (registered trademark) (XAREC (registered trademark)). The content of the SPS resin in the release layer forming resin containing the SPS resin as a main component is 70% by weight or more and 90% by weight or less, but preferably 85% by weight or more and 90% by weight or less.

The SPS resin is a resin having a syndiotactic structure, that is, a stereoregular structure in which phenyl groups and substituted phenyl groups as side chains are alternately located in opposite directions with respect to the main chain formed from carbon-carbon sigma bonds. is there.

As such SPS resin, for example, as disclosed in JP-A-2000-038461, racemic dyad is 75% or more, preferably 85% or more, or racemic pentad is 30% or more, preferably Polystyrene, poly (alkyl styrene), poly (aryl styrene), poly (halogenated styrene), poly (halogenated alkyl styrene), poly (alkoxy styrene), poly (vinyl benzoic acid) having a syndiotacticity of 50% or more Esters), hydrogenated polymers thereof and mixtures thereof, or copolymers based on these.

Examples of poly (alkyl styrene) include poly (methyl styrene), poly (ethyl styrene), poly (isopropyl styrene), poly (t-butyl styrene), and the like.

Examples of poly (aryl styrene) include poly (phenyl styrene), poly (vinyl naphthalene), poly (vinyl styrene), and the like.

Examples of poly (halogenated styrene) include poly (chlorostyrene), poly (bromostyrene), poly (fluorostyrene), and the like.

Examples of poly (halogenated alkylstyrene) include poly (chloromethylstyrene).

Examples of poly (alkoxystyrene) include poly (methoxystyrene) and poly (ethoxystyrene).

Of the above, polystyrene, poly (p-methylstyrene), poly (m-methylstyrene), poly (pt-ptylstyrene), poly (p-chlorostyrene), poly (m-chlorostyrene), Particularly preferred are poly (p-fluorostyrene), hydrogenated polystyrene and copolymers containing these structural units.

In such a case, the crystallinity of the release layer forming resin is preferably 14.0% or more and less than 60.0% as measured by a differential scanning calorimeter (DSC). This is because when the crystallinity of the release layer forming resin is as described above, better mold followability than that of a conventional release film can be obtained.

(3) a resin mainly composed of polybutylene terephthalate resin,
The resin containing polybutylene terephthalate as a main component preferably contains 80% by weight or more of polybutylene terephthalate, and more preferably contains 95% by weight or more. The first release layer 1 may be formed only from polybutylene terephthalate.

(4) Resin mainly composed of polyetherester block copolymer The resin composed mainly of polyetherester block copolymer contains 90% by weight or more of polyetherester block copolymer. Preferably, it is contained at 95% by weight or more. The first release layer 1 may be formed only from the polyether ester block copolymer.

The polyether ester block copolymer is mainly composed of a polyether segment and a polyester segment. The weight ratio of the polyether segment to the polyester segment is preferably in the range of 80:20 to 90:10. The structural unit of the polyether segment is preferably mainly an oxybutylene unit, and the structural unit of the polyester segment is preferably an ester unit mainly represented by the following chemical formula (I). Such polyetherester block copolymers are commercially available from Mitsubishi Engineering Plastics Co., Ltd. under the trade names Novaduran (registered trademark) 5505S and 5510S.

(5) TPX resin, SPS resin, polybutylene terephthalate resin, polyether ester block copolymer constituting resin release layer forming resin other than TPX resin, SPS resin, polybutylene terephthalate resin, polyether ester block copolymer Examples of other resins include elastomer resins, polyolefin resins, polystyrene resins, polyester resins, polyamide resins, polyphenylene ether resins, polyphenylene sulfide resins (PPS), and the like. In addition, these resin can be used individually or in combination of 2 or more types.

Examples of the elastomer resin include natural rubber, polybutadiene, polyisoprene, polyisobutylene, neoprene, polysulfide rubber, thiocol rubber, acrylic rubber, urethane rubber, silicone rubber, epichlorohydrin rubber, styrene-butadiene block copolymer (SBR). ), Hydrogenated styrene-butadiene block copolymer (SEB), styrene-butadiene-styrene block copolymer (SBS), hydrogenated styrene-butadiene-styrene block copolymer (SEBS), styrene-isoprene block copolymer (SIR), hydrogenated styrene-isoprene block copolymer (SEP), styrene-isoprene-styrene block copolymer (SIS), hydrogenated styrene-isoprene-styrene block copolymer (S PS), or ethylene propylene rubber (EPM), ethylene propylene diene rubber (EPDM), olefin rubber such as linear low density polyethylene elastomer, or butadiene-acrylonitrile-styrene-core shell rubber (ABS), methyl methacrylate- Butadiene-styrene-core shell rubber (MBS), methyl methacrylate-butyl acrylate-styrene-core shell rubber (MAS), octyl acrylate-butadiene-styrene-core shell rubber (MABS), alkyl acrylate-butadiene-acrylonitrile-styrene-core shell rubber ( ABS), butadiene-styrene-core shell rubber (SBR), siloxane-containing cores such as methyl methacrylate-butyl acrylate-siloxane Particulate elastic material of the core-shell type, such as Rugomu, or they were modified rubber, and the like.

Examples of the polyolefin resin include linear high-density polyethylene, linear low-density polyethylene, high-pressure low-density polyethylene, isotactic polypropylene, syndiotactic polypropylene, block polypropylene, random polypropylene, polybutene, 1,2- Examples thereof include polybutadiene, poly (4-methyl-1-pentene), cyclic polyolefin, and copolymers thereof (for example, ethylene-methyl methacrylate copolymer).

Examples of the polystyrene resin include atactic polystyrene, isotactic polystyrene, high impact polystyrene (HIPS), acrylonitrile-butadiene-styrene copolymer (ABS), acrylonitrile-styrene copolymer (AS), and styrene-meta. Acrylic acid copolymer, styrene-methacrylic acid / alkyl ester copolymer, styrene-methacrylic acid / glycidyl ester copolymer, styrene-acrylic acid copolymer, styrene-acrylic acid / alkyl ester copolymer, styrene -Maleic acid copolymer, styrene-fumaric acid copolymer and the like.

Examples of the polyester-based resin include polycarbonate, polyethylene terephthalate, polybutylene terephthalate, and the like.

Examples of the polyamide-based resin include nylon (registered trademark) 6, nylon (registered trademark) 6, 6, and the like.

(6) Other releasability forming resins include various additives such as anti-blocking agents, antioxidants, nucleating agents, antistatic agents, process oils, plasticizers, releasing agents, flame retardants, and flame retardant aids. Agents, pigments, etc. may be blended.

Examples of the anti-blocking agent include the following inorganic particles or organic particles. Inorganic particles include Group IA, Group IIA, Group IVA, Group VIA, Group VIIA, Group VIIIA, Group IB, Group IIB, Group IIIB, Group IVB oxides, hydroxides, sulfides, nitrides, halogens , Carbonates, sulfates, acetates, phosphates, phosphites, organic carboxylates, silicates, titanates, borates and their water-containing compounds, and composite compounds and natural mineral particles centered on them Is mentioned.

Specific examples of such inorganic particles include group IA element compounds such as lithium fluoride and borax (sodium borate hydrate); magnesium carbonate, magnesium phosphate, magnesium oxide (magnesia), magnesium chloride, acetic acid Magnesium, magnesium fluoride, magnesium titanate, magnesium silicate, magnesium silicate hydrate (talc), calcium carbonate, calcium phosphate, calcium phosphite, calcium sulfate (gypsum), calcium acetate, calcium terephthalate, calcium hydroxide, silicic acid Group IIA element compounds such as calcium, calcium fluoride, calcium titanate, strontium titanate, barium carbonate, barium phosphate, barium sulfate, barium sulfite; titanium dioxide (titania), titanium monoxide, titanium nitride, two Group IVA element compounds such as zirconium fluoride (zirconia) and zirconium monoxide; Group VIA element compounds such as molybdenum dioxide, molybdenum trioxide and molybdenum sulfide; Group VIIA element compounds such as manganese chloride and manganese acetate; Cobalt chloride and cobalt acetate Group VIII element compounds; Group IB element compounds such as cuprous iodide; Group IIB element compounds such as zinc oxide and zinc acetate; Aluminum oxide (alumina), aluminum hydroxide, aluminum fluoride, alumina silicate (alumina silicate) Group IIIB element compounds such as silicon oxide (silica, silica gel), graphite, carbon, graphite, glass, etc .; Carnal stone, kainite, mica (mica, quinumo), villose ore, etc. Of natural mineral particles

Examples of the organic particles include a fluororesin, a melamine resin, a styrene-divinylbenzene copolymer, an acrylic resin silicone, and a crosslinked product thereof.

The average particle size of the above-mentioned inorganic particles and organic particles is preferably 0.1 to 10 μm, and the addition amount is preferably 0.01 to 15% by weight.

In addition, these antiblocking agents can be used individually or in combination of 2 or more types.

Examples of the antioxidant include phosphorus antioxidants, phenol antioxidants, sulfur antioxidants, 2-[(1-hydroxy-3,5-di-t-pentylphenyl) ethyl] -4, Examples include 6-di-t-pentylphenyl acrylate. These antioxidants can be used alone or in combination of two or more.

Examples of the nucleating agent include metal salts of carboxylic acids such as aluminum di (pt-butylbenzoate), metal salts of phosphoric acid such as methylenebis (2,4-di-t-butylphenol) acid phosphate sodium, talc, And phthalocyanine derivatives. In addition, these nucleating agents can be used individually or in combination of 2 or more types.

Examples of the plasticizer include polyethylene glycol, polyamide oligomer, ethylene bisstearamide, phthalate ester, polystyrene oligomer, polyethylene wax, silicone oil, and the like. In addition, these plasticizers can be used individually or in combination of 2 or more types.

Examples of the release agent include polyethylene wax, silicone oil, long chain carboxylic acid, and long chain carboxylic acid metal salt. In addition, these mold release agents can be used individually or in combination of 2 or more types.

Examples of the process oil include paraffinic oil, naphthenic oil, and aroma oil. Of these, paraffinic oils having a percentage of the number of carbon atoms related to paraffin (straight chain) calculated by the ndM method to the total number of carbon atoms of 60% Cp or more are preferable.

The viscosity of the process oil is preferably 15 to 600 cs at 40 ° C., more preferably 15 to 500 cs. The amount of process oil added is preferably 0.01 to 1.5 parts by weight, more preferably 0.05 to 1.4 parts by weight, based on 100 parts by weight of the release-forming resin. More preferably, the content is 0.1 to 1.3 parts by weight. In addition, these process oil can be used individually or in combination of 2 or more types.

(7) Release layer thickness The first release layer 1 has a thickness of 10 to 100 µm, preferably 15 to 50 µm. If the release layer is thinner than this, the release layer is broken after press lamination, and the release layer resin tends to remain on the FPC side when the FPC and release film are separated. On the other hand, when it is thicker than the above range, the embedding property is deteriorated, the anti-shape following property is inferior, and the flow amount of the adhesive attached to the coverlay tends to increase.

The release film 10 is not particularly limited, but is preferably 40 μm or more and 200 μm or less, and more preferably 50 μm or more and 160 μm or less. By being within the preferable range, workability can be improved.

<Method for producing release film>
The release film 20 according to the present embodiment can be manufactured by a method such as a coextrusion method or an extrusion lamination method.

In the coextrusion method, the release film 20 is manufactured by simultaneously extruding the first release layer 1, the first resin layer 2, and the second resin layer 3 using a feed block and a multi-manifold die. In the coextrusion method, the melt M that has passed through the die 510 is guided to the first roll 530 and fixed to the first roll 530 by the touch roll 520 as shown in FIG. The release film 200 is cooled by the first roll 530 until it is detached from the 530. Thereafter, the release film 200 is sent to the downstream side in the film feeding direction (see the arrow in FIG. 2) by the second roll 540, and is finally taken up by a take-up roll (not shown). At this time, the temperature of the first roll 530 is preferably 30 to 100 ° C., the temperature of the touch roll 520 is preferably 30 to 100 ° C., and the peripheral speed of the second roll 540 with respect to the first roll 530. The ratio is preferably from 0.990 to 0.998.

In the extrusion laminating method, the temperature of the extruder cylinder is set to 200 to 300 ° C. to extrude the first release layer 1, and the first release layer 1 is combined with the first resin layer 2 and the second resin layer 3. The release film 20 is manufactured by laminating the first release layer 1 and the cushion layer 20 by merging. In the extrusion laminating method, the release layer forming resin melt M that has passed through the die 510 is guided to the first roll 530 and fixed to the first roll 530 by the touch roll 520 as shown in FIG. Before being released from the first roll 530 and cooled by the first roll 530 to form the release layer film F. Thereafter, the release layer film F is sent downstream by the second roll 540 in the film feeding direction (see the arrow in FIG. 2). And the melt (not shown) of cushion layer formation resin is made to merge with release layer film F sent to the film feed direction downstream side, and it is integrated with release layer film F, and release film 200 is made. Manufactured. In addition, the release film 200 manufactured in this way is further wound up by the winding roll (not shown) provided in the film feed direction downstream side. At this time, the temperature of the first roll 530 is preferably 30 to 100 ° C., the temperature of the touch roll 520 is preferably 30 to 100 ° C., and the circumference of the second roll 540 with respect to the first roll 530 is The speed ratio is preferably 0.990 to 0.998.

If necessary, crystallization of the TPX resin, SPS resin, polybutylene terephthalate resin, and polyetherester block copolymer in the first release layer 1 of the release film 200 obtained as described above is performed. The degree may be adjusted by a known heat treatment apparatus. For example, the heat treatment may be performed in the vicinity of 50 to 220 ° C. using a method of heat-setting the release film 200 in a dryer using a tenter device or a heat treatment roll.

Second Embodiment
As shown in FIG. 3, the release film 10 of the second embodiment includes a first release layer 1, a cushion layer 20 having a first resin layer 2 and a second resin layer 3, and a second release mold. Layer 4 is laminated in this order. In the following description, for convenience of explanation, the upper side of FIG. 3 is referred to as “upper” and the lower side is referred to as “lower”.

  Hereinafter, although the second embodiment will be described, the description will focus on the differences from the first embodiment, and the description of the same matters will be omitted. In the present embodiment, the same components as those of the first embodiment are denoted by the same reference numerals as those of the components described above, and detailed description thereof is omitted.

The release film 10 of the second embodiment is a release film having another release layer on the lower surface of the release film according to the first embodiment. By setting it as the said structure, the mold release property from the metal mold | die after a hot press improves. The second release layer 4 can be the same as the first release layer 1 in the first embodiment, and the first release layer 1 and the second release layer in the second embodiment can be used. It is preferable to use the same release layer in the mold layer 4. By using the same thing as the 1st mold release layer 1 and the 2nd mold release layer 4, the curvature of a mold release film can be controlled.

The first release layer 1, the first resin layer 2, and the second resin layer 3 in the second embodiment are also the first release layer 1, the first resin layer 2, and the second resin in the first embodiment. The thing similar to the resin layer 3 can be used.

The release film 10 is not particularly limited, but is preferably 40 μm or more and 200 μm or less, and more preferably 50 μm or more and 160 μm or less. By being within the preferable range, workability can be improved.

<Third Embodiment>
As shown in FIG. 4, the release film 10 of the third embodiment includes the first release layer 1, the first resin layer 2 on the upper surface of the second resin layer 3, and the first resin layer 5 on the lower surface. The cushion layer 20 which has and the 2nd mold release layer 4 are laminated | stacked in this order. In the following description, for convenience of explanation, the upper side of FIG. 4 is referred to as “upper” and the lower side is referred to as “lower”.

In the following, the third embodiment will be described. The description will focus on the differences from the first embodiment, and the description of the same matters will be omitted. In the present embodiment, the same components as those of the first embodiment are denoted by the same reference numerals as those of the components described above, and detailed description thereof is omitted.

The release film 10 of the third embodiment is a release film having another first resin layer 5 on the lower surface of the cushion layer in the release film according to the second embodiment. By setting it as the said structure, the embedding property to a circuit exposure film improves in a heating press. The first resin layer 5 can be the same as the first resin layer 2, and the first resin layer 2 and the first resin layer 5 in the third embodiment are preferably the same. By using the same thing about the 1st resin layer 5 and the 1st resin layer 2, the curvature of a release film can be controlled.

The first release layer 1, the first resin layer 2, and the second resin layer 3 in the third embodiment are also the first release layer 1, the first resin layer 2, and the second resin in the first embodiment. The thing similar to the resin layer 3 can be used.

The release film 10 is not particularly limited, but is preferably 40 μm or more and 200 μm or less, and more preferably 50 μm or more and 160 μm or less. By being within the preferable range, workability can be improved.

As mentioned above, although the release film of this invention was shown and demonstrated 1st Embodiment, 2nd Embodiment, and 3rd Embodiment, it is not limited to these embodiments.

<Example of use of release film>
The release film 100 according to the embodiment of the present invention is disposed so as to wrap the CL film so that the CL film adheres to the concavo-convex portion of the circuit pattern when the CL film adheres to the circuit exposed film. At the same time, it is pressurized by a press device. Specifically, as shown in FIG. 5, the release film 100 is obtained by sandwiching a circuit-exposed film and a CL film temporarily fixed with an adhesive 340 so that the release layers face each other. The sheet is sequentially sandwiched between a Teflon (registered trademark) sheet 330, a rubber cushion 320, and a stainless steel plate 310, and pressed by a hot platen 300 (see white arrows in FIG. 5). The heating method using the hot platen 300 is as shown in FIG. That is, the hot platen 300 is heated from room temperature to 185 ° C. in 20 seconds to 1 minute from the start of pressurization, and then maintained at that temperature for 2 minutes. Thereafter, the hot platen 300 is cooled from 185 ° C. to room temperature over 20 seconds to 1 minute. In addition, the press pressure at this time is suitably adjusted at 2-20 MPa.

<Example>
EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated in detail, this invention is not restrict | limited at all by these Examples.

Example 1
1. Production of release film (1) Release layer raw material TPX resin (TPX (registered trademark) MX002 manufactured by Mitsui Chemicals, Inc.) is used as the first release layer and second release layer raw material. It was.

(2) Raw material for cushion layer As raw material for the first resin layer in the cushion layer, ethylene-methyl methacrylate copolymer (methyl methacrylate derived unit content: 5% by weight) (Aclift manufactured by Sumitomo Chemical Co., Ltd.) (Registered Trademark) WD106) (hereinafter referred to as “EMMA”) was used as a raw material for the second resin layer, using polypropylene (manufactured by Sumitomo Chemical Co., Ltd., Nobrene (registered trademark) (hereinafter referred to as “PP”)). The Vicat softening point of PP was 80 ° C., and that of PP was 160 ° C.

(3) Production of release film Using co-extrusion method, a first resin layer, a second resin layer, a cushion layer configured in the order of the first resin layer, and a first release layer on the front and back of the cushion layer A release film having a second release layer was produced.

  Specifically, a release film was produced by simultaneously extruding TPX resin, EMMA and PP using a multi-manifold die. In addition, the temperature of the 1st roll 530 at this time was 30 degreeC, the temperature of the touch roll 520 was 30 degreeC, and the peripheral speed ratio of the 2nd roll 540 with respect to the 1st roll 530 was 0.990.

  The thicknesses of the first release layer and the second release layer of this release film were both 28 μm, the thickness of the first resin layer in the cushion layer was 12 μm, and the thickness of the second resin layer was 20 μm. It was.

2. CL film adhesion test Actually, the circuit exposed film temporarily clamped with an adhesive is wrapped with the release film so that the first release layer faces the circuit exposed film from both sides. The sample was heated and pressed with the heating pattern shown in FIG. As a result, the amount of the adhesive between the circuit exposed film and the CL film that flowed out to the circuit pattern (hereinafter referred to as the amount of CL adhesive exudation) was 70 μm, indicating good embedding of the release film (Table). 1). Moreover, the peeling defect of the release film after a hot press did not generate | occur | produce, but it became a favorable result (refer Table 1). The smaller the amount of the CL adhesive oozing out, the better the embedding property. In this test, the CL adhesive exudation amount of less than 90 μm is excellent in embedding property and is determined as A. On the other hand, when the CL adhesive oozing amount was 90 μm or more, the embedding property was inferior, and B was determined. In the evaluation of releasability, if the release film can be easily peeled at the time of release, the release property is judged as A as good release, and if the release film is taken to the mold at the time of release, the release property is B was determined as insufficient. In addition, the evaluation of wrinkles is performed by observing the release film after hot pressing, and when no wrinkles are observed, it is determined as A with a good suppression of wrinkles. did.

(Example 2)
A release film was prepared and evaluated in the same manner as in Example 1 except that the configuration of the release film was changed as shown in Table 1. The results are shown in Table 1.

(Example 3)
A release film was prepared and evaluated in the same manner as in Example 1 except that the configuration of the release film was changed as shown in Table 1. The results are shown in Table 1.

Example 4
The structure of the release film was changed to Example 1 except that the second resin layer was changed to polybutylene terephthalate (Novaduran (registered trademark) 5020 manufactured by Mitsubishi Engineering Plastics) (hereinafter referred to as “PBT1”). A release film having the same layer structure was produced and evaluated. The results are shown in Table 1.

(Example 5)
The structure of the release film was the same as in Example 1 except that the second resin layer was changed to 6-nylon (UBE nylon (registered trademark) 1022B manufactured by Ube Industries, Ltd.) (hereinafter referred to as “PA”). A release film having a layer structure of was prepared and evaluated. The results are shown in Table 1.

(Example 6)
Polybutylene terephthalate / polytetramethylene glycol block copolymer (polybutylene terephthalate structural unit / polytetramethylene glycol structural unit 90 parts by weight / 10 parts by weight) (Novaduran manufactured by Mitsubishi Engineering Plastics Co., Ltd.) (Registered trademark) 5505S) (hereinafter referred to as “PBT2”), a release film was prepared in the same manner as in Example 1 except that the thickness configuration of the release film was as shown in Table 1. went. The results are shown in Table 1.

(Example 7)
Except that SPS resin (Zarek (registered trademark) S107 manufactured by Idemitsu Kosan Co., Ltd.) was used as a release layer raw material, and the configuration of the release film was changed as shown in Table 1, it was the same as in Example 1. A release film was prepared and evaluated. The results are shown in Table 1.

(Example 8)
SPS is used as a raw material for the release layer, and the second resin layer is changed to polycarbonate (Iupilon (registered trademark) E-2000 manufactured by Mitsubishi Engineering Plastics Co., Ltd.) (hereinafter referred to as “PC”). A release film was prepared and evaluated in the same manner as in Example 1 except that the configuration was changed as shown in Table 2. The results are shown in Table 2.

Example 9
A release film was prepared in the same manner as in Example 1 except that SPS was used as a raw material for the release layer, the second resin layer was changed to PBT1, and the configuration of the release film was changed as shown in Table 2. And evaluated. The results are shown in Table 2.

(Comparative Example 1)
As shown in Table 1, the release film was prepared and evaluated in the same manner as in Example 1 except that the cushion layer was changed to one EMMA layer having a thickness of 44 μm as shown in Table 1. The results are shown in Table 1.

(Comparative Example 2)
As shown in Table 1, a release film was prepared and evaluated in the same manner as in Example 1 except that the cushion layer was changed to a PP layer of 44 μm as shown in Table 1. The results are shown in Table 1.

(Comparative Example 3)
As shown in Table 2, the release film was prepared in the same manner as in Example 1 except that the release layer was changed to SPS with a thickness of 20 μm and the cushion layer was changed to EMMA with a thickness of 44 μm. Went. The results are shown in Table 2.

(Comparative Example 4)
As shown in Table 2, the release film was prepared in the same manner as in Example 1 except that the release layer was changed to SPS having a thickness of 20 μm and the cushion layer was changed to PP having a thickness of 44 μm. Went. The results are shown in Table 2.

  As is clear from the results in Tables 1 and 2, the release film of the present invention has the ability to embed in a circuit-exposed film and the release property after pressure press in a heating press when producing a circuit board. It can be compatible.

DESCRIPTION OF SYMBOLS 1 1st release layer 2 1st resin layer 3 2nd resin layer 4 2nd release layer 5 1st resin layer 10 Release film 20 Cushion layer 100 Release film 200 Release film 300 Hot plate 310 Stainless steel plate 320 Rubber cushion 330 Teflon (registered trademark) sheet 340 A circuit-exposed film and a CL film temporarily fixed with an adhesive 510 Dice 520 Touch roll 530 First roll 540 Second roll

 The release film according to the present invention is characterized in that the workability of the hot press can be improved, and the rate of non-defective products such as FPC can be increased, and the CL film adheres to the circuit exposed film by the hot press. It is particularly useful as a release film that is sometimes used to wrap a coverlay film in order to bring the CL film into close contact with the uneven portion of the circuit pattern.

  Other known release films include (1) those used in the production of laminates, (2) those used in the production of advanced composite materials, and (3) those used in the production of sports and leisure goods. The release film according to the present invention is also useful as these release films. Note that the release film used in the production of the laminated board is a press-molding process for producing a multilayer printed board, in order to prevent adhesion between the printed board and the separator plate or other printed boards. It is an intervening film. Moreover, the release film used at the time of manufacture of advanced composite material products is, for example, a film used when various products are manufactured by curing a prepreg made of glass cloth, carbon fiber or aramid fiber and an epoxy resin. The release film used in the production of sports / leisure goods is, for example, the manufacture of fishing rods, golf club shafts, windsurfing poles, etc., when the prepreg is rolled into a cylindrical shape and cured in an autoclave. It is a film that is wound on top.

  The release film is also useful as a release film for adhesive tape, double-sided tape, masking tape, label, seal, sticker, poultice for skin application, and the like.

  This release film is also useful as a process film used in the production of printed circuit boards, ceramic electronic parts, thermosetting resin products, decorative boards and the like. The process film referred to here means that the metal plate or resin is not bonded to each other during the molding process when manufacturing printed circuit boards, ceramic electronic parts, thermosetting resin products, decorative boards, etc. It refers to a film that is sandwiched between metal plates or between resins, and is particularly suitable for use in the production of laminated plates, the production of flexible printed circuit boards, the production of advanced composite materials, and the production of sports and leisure goods.

Claims (12)

A release film having a cushion layer and a release layer,
The cushion layer has a first resin layer and a second resin layer,
A release film, wherein the Vicat softening point X (° C) of the first resin layer is different from the Vicat softening point Y (° C) of the second resin layer. The release film according to claim 1, wherein the Vicat softening point X (° C.) of the first resin layer and the Vicat softening point Y (° C.) of the second resin layer satisfy X <Y. The release film according to claim 1 or 2, wherein the Vicat softening point X (° C) of the first resin layer and the Vicat softening point Y (° C) of the second resin layer satisfy YX> 50. The release film according to any one of claims 1 to 3, wherein the first resin layer has a Vicat softening point X (° C) of 80 or more. The release film according to any one of claims 1 to 4, wherein the thickness of the second resin layer is 5% or more and 50% or less of the entire release film. The release film according to any one of claims 1 to 5, wherein the second resin layer contains one or more resins made of a group of polypropylene, polyester, polyamide, and polyether. The release film according to any one of claims 1 to 6, wherein the cushion layer includes two first resin layers.   The release film according to any one of claims 1 to 7, wherein the release layer is mainly composed of polyolefin, polyester, or polystyrene.   The release film according to claim 8, wherein the polyolefin contained in the release layer is 1.4 methylpentene.   The release film according to claim 8 or 9, wherein the polyester contained in the release layer is polybutylene terephthalate.   The release film according to any one of claims 8 to 10, wherein the polystyrene contained in the release layer is syndiotactic polystyrene.   A release film having a first release layer, a cushion layer, and a second release layer in this order, wherein the cushion layer has the first resin layer on both surfaces of the second resin layer. The release film in any one of 7-11.

Images