TW202313301A - Mold releasing film and method for manufacturing molded product - Google Patents

Abstract

A mold releasing film 10 of the present invention includes a first release layer 1 comprising a first thermoplastic resin composition and a cushion layer 3 comprising a third thermoplastic resin composition. A complex shear modulus of the mold releasing film 10 at 80ºC is 1.00 MPa or less. Further, it is preferred that a storage modulus of the cushion layer 3 at 150ºC is 9.0 MPa or more.

Description

Release film and manufacturing method of molded article

The present invention relates to a method for manufacturing a release film and a molded product.

In recent years, when a flexible printed circuit board, that is, a laminate is formed by bonding the cover film to the flexible circuit board with exposed circuits by heating and pressing through the adhesive layer included in the cover film, a mold release film is generally used.

When forming a flexible printed circuit board using such a release film, in other words, a laminate of a flexible circuit board and a cover film, the release film is required to have two characteristics, namely, embedding properties and mold release properties. By.

Specifically, firstly, a concave portion is formed on a flexible printed circuit board by laminating a cover film on the flexible printed circuit board, but the mold release film is required to exhibit excellent filling properties for the concave portion.

More specifically, the cover film is laminated on the flexible circuit board via the adhesive layer included in the cover film. In this lamination, the mold release film is required to exhibit excellent embedding properties in the recessed portion, and to suppress the adhesive from penetrating into the recessed portion.

In addition, after laminating a cover film on a flexible printed circuit board as described above, it is required to peel off a release film having excellent releasability from the formed flexible printed circuit board.

More specifically, when the release film is peeled from the formed flexible printed circuit board, the release film is required to exhibit excellent mold release properties on the flexible printed circuit board and to suppress elongation and breakage in the flexible printed circuit board .

In order to produce a release film having the above two properties (fillability and release properties), for example, in Patent Document 1, it is proposed to have a polyester elastomer layer as a release layer and a cushioning layer as a buffer. The release film of the polyester layer of the layer.

In this mold release film, in the state arrange|positioned so that a mold release layer may contact a flexible printed circuit board, a mold release film fills in a recessed part. Thereby, embedding properties are imparted to the release film, but from the viewpoint of suppressing penetration of the adhesive into the recesses, the development of a release film exhibiting more excellent embedding properties in the recesses is actually required.

Moreover, regarding such a problem, it also occurs in the following case in the same way: by making the state where the release film is adhered to the object formed of the material containing the thermosetting resin in a semi-cured state, and making the thermosetting resin in this state The resin is cured, and the object is used to manufacture a molded product with a concave portion. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Unexamined Patent Publication No. 2011-88351

[Problem to be Solved by the Invention]

An object of the present invention is to provide a release film capable of exhibiting excellent embedding properties in recesses and a method for producing a molded article using the release film. [Technical means to solve the problem]

Such objects are achieved by the present invention described in the following (1) to (14). (1) A release film having a first release layer made of a first thermoplastic resin composition and a buffer layer made of a third thermoplastic resin composition, characterized in that, The complex shear elastic modulus at 80° C. of the release film is 1.00 MPa or less.

(2) The release film according to (1) above, wherein, The buffer layer has a storage modulus of elasticity at 150° C. of 9.0 MPa or more.

(3) The release film according to (1) or (2) above, wherein, The storage shear elastic modulus at 80° C. of the release film is 1.00 MPa or less.

(4) The release film according to any one of the above (1) to (3), wherein, The loss shear elastic modulus at 80° C. of the release film is 0.40 MPa or less.

(5) The release film according to any one of the above (1) to (4), wherein, In the said 1st mold release layer, the 10 point average roughness (Rz) of the surface of the side opposite to the said buffer layer is 0.5 micrometer or more and 3.6 micrometers or less.

(6) The release film according to any one of (1) to (5) above, wherein The storage elastic modulus E' at 150°C of the first release layer is 100 MPa or more.

(7) The release film according to any one of (1) to (6) above, wherein The aforementioned first thermoplastic resin composition contains a polyester-based resin as a main material.

(8) The release film according to any one of (1) to (7) above, wherein The buffer layer has an average thickness of not less than 60 μm and not more than 200 μm.

(9) The release film according to any one of (1) to (8) above, wherein The average thickness of the said 1st mold release layer is 5 micrometers or more and 30 micrometers or less.

(10) The release film according to any one of the above (1) to (9), wherein, The third thermoplastic resin composition contains a plurality of thermoplastic resins, and the melting point of the thermoplastic resin is less than 80°C.

(11) The release film according to (10) above, wherein, The third thermoplastic resin composition contains a polyester resin and a polyolefin resin as the thermoplastic resin.

(12) The release film according to any one of (1) to (11) above, wherein This mold release film has the 2nd mold release layer which consists of a 2nd thermoplastic resin composition laminated|stacked on the side opposite to the said 1st mold release layer of the said buffer layer.

(13) The release film according to any one of (1) to (12) above, wherein This release film is used to form circuits.

(14) A method of manufacturing a molded article, comprising forming the first release layer of the release film of any one of the above (1) to (13) on the object so that the first release layer is on the object side. The step of arranging the release film and the step of heating and pressing the object on which the release film is arranged, in the step of arranging the release film, the side of the object on which the release film is arranged The surface is formed of a material containing a thermosetting resin in a semi-cured state. [Effect of Invention]

According to the present invention, it is possible to obtain a release film that exhibits excellent embedding properties in recesses.

Therefore, when the release film is used, for example, to form a flexible printed circuit board using a flexible circuit board and a cover film, the release film having excellent embedding properties can be embedded in the flexible printed circuit board formed. The concave part of the circuit board. Therefore, when the recess is formed on the flexible printed circuit board, it is possible to reliably suppress or prevent the adhesive agent from penetrating into the formed recess from the adhesive layer included in the cover film.

Hereinafter, the method of manufacturing the mold release film and molded article of the present invention will be described in detail based on preferred embodiments shown in the drawings.

In addition, below, the case where the flexible printed circuit board is manufactured in multilayer using the release film of this invention, that is, the case where the release film of this invention is used for circuit formation is demonstrated as an example. Moreover, before explaining the manufacturing method of the mold release film and molded article of this invention, the manufacturing method which manufactures a flexible printed circuit board in multilayer is demonstrated first.

<Manufacturing method of flexible printed circuit board> Fig. 1 is a longitudinal sectional view for explaining a method of manufacturing a flexible printed circuit board in a multilayered state. Fig. 2 is a longitudinal cross-sectional view showing each step in a method of manufacturing a flexible printed circuit board in a multilayered state. Fig. 3 is a longitudinal sectional view showing an embodiment of the release film of the present invention. Fig. 4 is a partially enlarged longitudinal sectional view obtained by partially enlarging part A of the release film shown in Fig. 3 . Furthermore, in the following, for convenience of description, the upper side in FIGS. The right side is called "right".

In this embodiment, the manufacturing method for manufacturing the flexible printed circuit board 200 (hereinafter, sometimes referred to as "FPC200") as multilayer includes: the first step, which is to separate the sheet-shaped glass cloth 300A, the mold release Film 10A, FPC200, release film 10B, and glass cloth 300B are stacked in sequence. The laminated volume layer is multi-layered; in the second step, by heating and pressing the multi-layered laminated body separately, in FPC200, the cover film 220 (hereinafter, sometimes referred to as "CL film 220") is bonded to the flexible circuit board 210; The FPC 200 with the CL film 220 bonded thereon. In addition, the manufacturing method of the molded article of this invention is applied to the manufacturing method of this FPC200.

Hereinafter, each step will be described in order. (step 1) First, the laminated volume layer in which the sheet-shaped glass cloth 300A, release film 10A, FPC 200, release film 10B, and glass cloth 300B are sequentially stacked is multilayer (see FIG. 1 and FIG. 2( a ). ). In addition, below, the case where the said build-up bulk layer is two layers is demonstrated.

(1-1) First, three flat plate-shaped thermocompression bonding plates 521 are prepared, and arranged so as to form two gaps in the thickness direction thereof.

(1-2) Next, in the two gaps, the glass cloth 300A, the release film 10A, the FPC 200, the release film 10B, and the glass cloth 300B, which are each in the form of a sheet (film), are sequentially arranged from the upper side to the lower side. Overlapped state configuration. Furthermore, in this step (1-2), the FPC 200 disposed in the gap is in a state of being laminated by overlapping the flexible circuit board 210 and the CL film 220, but the flexible circuit board 210 and the CL film 220 are not covered by the CL film. The adhesive layer 222 included in the film 220 is bonded.

Thereby, as shown in FIG. 1 , between the heating and pressing plates 521, the laminated volume layer of the state in which the glass cloth 300A, the release film 10A, the FPC 200 , the release film 10B, and the glass cloth 300B are sequentially stacked is 2. layer.

Furthermore, this step (1-2) constitutes a step of arranging a release film on the object (FPC200) in the manufacturing method of the molded article of the present invention.

(step 2) Next, by going through the above-mentioned first step, the multilayer laminated body is heated and pressed respectively, thereby bonding the CL film 220 and the flexible circuit board 210 in the FPC 200 (see FIG. 1 and FIG. 2( b ). ).

(2-1) First, the heating and pressing plate 521 is heated while the glass cloth 300 ( 300A, 300B) is in contact with the heating and pressing plate 521 .

Thereby, the laminated body which laminated|stacked glass cloth 300A, mold release film 10A, FPC200, mold release film 10B, and glass cloth 300B is heated by the heat transfer from the heating pressure bonding plate 521.

In this step (2-1), the temperature for heating FPC 200 which is a laminate is not particularly limited, but is preferably 100°C to 250°C, more preferably 150°C to 200°C, for example.

Also, the time for heating the laminate is not particularly limited, but is preferably 40 sec to 5000 sec, more preferably 200 sec to 4000 sec. Thereby, glass cloth 300A, release film 10A, FPC200, release film 10B, and glass cloth 300B in a laminate can be heated substantially uniformly.

(2-2) Also, almost simultaneously with the heating of the thermocompression bonding plate 521 in the aforementioned step (2-1), the thermocompression bonding plate 521 positioned on the upper side and the thermocompression bonding plate 521 positioned on the lower side are aligned. The thickness directions of these are close (press forming method).

As a result, in the laminate in which the glass cloth 300A, the mold release film 10A, the FPC 200 , the mold release film 10B, and the glass cloth 300B respectively disposed in the two spaces formed between the three heat-compression bonding plates 521 are stacked, the Glass cloth 300A, 300B, release film 10A, 10B, FPC200 are pressurized (refer FIG. 1, FIG. 2(b)).

Thereby, since FPC200 is heated and pressurized, in FPC200, the superimposed flexible circuit board 210 and CL film 220 are bonded via the adhesive layer 222 with which CL film 220 is equipped. In other words, the cover layer 221 is bonded to the flexible circuit board 210 via the adhesive layer 222 . Also, when the FPC 200 is heated/pressurized, that is, when the cover layer 221 and the flexible circuit board 210 are bonded via the adhesive layer 222 , the release film 10 is embedded in the concave portion 223 formed in the cover layer 221 . Therefore, it is possible to suppress the adhesive from the adhesive layer 222 from penetrating into the concave portion 223 (see FIG. 2( b )).

In this step (2-2), the pressure for pressurizing FPC 200 is not particularly limited, but is preferably 0.1 MPa to 20.0 MPa, more preferably 0.5 MPa to 15.0 MPa.

Also, the time for pressurizing the FPC 200 is not particularly limited, but is preferably not less than 20 sec and not more than 5000 sec, more preferably not less than 100 sec and not more than 4000 sec.

By setting the pressure and time for pressurizing the FPC 200 within the aforementioned ranges, the cover layer 221 and the flexible circuit board 210 can be reliably bonded via the adhesive layer 222 .

Furthermore, this step (2-2) constitutes a step of heating and pressing the object (FPC200) on which the release film 10 is arranged in the manufacturing method of the molded article of the present invention. Moreover, when the cover layer 221 is comprised by the material containing the thermosetting resin in a semi-cured state, the cover layer 221 comprises the surface of the object (FPC200) on which the release film 10 is arrange|positioned. Furthermore, since the release film 10 is laminated so that the surface on the side of the first release layer 1 described later is in contact with the surface of the cover layer 221, the cover layer 221 in which the concave portion 223 is formed can be maintained by the release film 10. Since the thermosetting resin is cured, the cover layer 221 (molded product) can be molded on the flexible circuit board 210 with excellent precision.

Also, in the above, the heating of the FPC 200 in the aforementioned step (2-1) and the pressurization of the FPC 200 in the present step (2-2) are preferably carried out almost simultaneously as described above, but it is also possible to perform the heating of the FPC 200 in the step (2-1) ) and steps (2-2) are implemented in sequence. However, by implementing step (2-1) and step (2-2) almost simultaneously, shortening of the time required for manufacturing FPC200 can be aimed at shortening a 2nd step.

(step 3; step (3)) Next, release film 10 (10A, 10B) is released from FPC200, and FPC200 in which CL film 220 is bonded to flexible circuit board 210 is obtained (see FIG. 2( c ).).

The release method for releasing the release film 10 from the FPC 200 is not particularly limited, but a method in which, for example, one end of the release film is held by hand and peeled in a direction of 90° to 180° is preferably used.

Furthermore, when the release film 10 is peeled from the FPC 200 , when excellent release properties are exhibited between the heat-compression bonding plate 521 and the release film 10 , the contact between the heat-pressure bonding plate 521 and the release film 10 may be omitted. Glass cloth 300 is arranged between them.

Through the above-mentioned steps, the manufacturing method of the flexible printed circuit board 200 using the mold release film 10 is comprised.

Moreover, as the release film 10 suitable for manufacture of this flexible printed circuit board 200, the release film of this invention is used. That is, as the release film 10, the release film having the first release layer 1 made of the first thermoplastic resin composition, the buffer layer 3 made of the third thermoplastic resin composition, and the second thermoplastic resin composition can be used. The second release layer 2 composed of the composition is sequentially laminated with the first release layer 1, the buffer layer 3 and the second release layer 2, and the complex shear elastic modulus of the release film 10 at 80°C is 1.00 MPa the following.

Here, as described above, in the method of manufacturing the flexible printed circuit board 200 using the release film 10, it is required to balance the filling of the concave portion 223 with the release film 10 and the release from the flexible printed circuit board 200. sex.

However, from the viewpoint of suppressing the penetration of the adhesive from the adhesive layer 222 into the recess 223, it is practical to consider the embedding properties of the release film 10 formed in the recess 223 of the flexible printed circuit board 200. Therefore, it is required to develop a release film 10 that exhibits a more excellent embedding property for the concave portion 223 in the aforementioned step (2-2).

Corresponding to such actual conditions, in the present invention, as the release film 10, a release film having a complex shear elastic modulus at 80° C. of 1.00 MPa or less is selected. Thereby, the mold release film 10 exhibits a better embedding property for the mold release film 10 formed in the concave portion 223 of the flexible printed circuit board 200 , thereby suppressing penetration of the adhesive originating from the adhesive layer 222 into the concave portion 223 .

Hereinafter, the release film 10 to which the release film of the present invention is applied will be described. ＜Release film 10＞ As shown in FIG. 3 , in this embodiment, the release film 10 is composed of a laminate in which the first release layer 1, the buffer layer 3 and the second release layer 2 are sequentially laminated, and the first release layer 1 The surface on the side is overlapped and used so as to be in contact with the CL film 220 included in the FPC 200 .

As the release film 10 , as described above, in the present invention, a release film whose complex shear elastic modulus at 80° C. is 1.00 MPa or less is selected. Thereby, the mold release film 10 provided with the more excellent followability can be obtained.

The release film 10 has better followability, so that in the aforementioned step (2-2) of the flexible printed circuit board 200 using the release film 10 , the overlapping flexible circuit boards are joined through the adhesive layer 222 210 and CL film 220, the first release layer 1 is pressed into the layer of the first release layer 1 in such a way that it follows the shape of the concave portion 223 formed by the flexible circuit board 210 and the CL film 220, and functions as a buffer. effect. Moreover, since the release film 10 is provided with the buffer layer 3 , the CL film 220 can be pressed against the flexible circuit board 210 with a uniform pressure by the release film 10 .

In particular, as described above, in the case where the heating of the FPC 200 in the aforementioned step (2-1) and the pressurization of the FPC 200 in the aforementioned step (2-2) are carried out almost simultaneously, the FPC 200 in the aforementioned step (2-1) Heating has lower responsiveness than pressurization of FPC 200 in the aforementioned step (2-2). That is, when the heating and pressurization of the FPC 200 are performed almost simultaneously, it takes a long time for the FPC 200 to reach the desired heating temperature compared to the fact that the desired pressure can be applied to the FPC 200 relatively early.

Therefore, before FPC200 is heated at the target heating temperature, the target pressure is given to FPC200. Therefore, considering the heating temperature of the FPC 200 in the aforementioned step (2-1), for example, even if the elastic modulus of the release film 10 in the range of 100° C. to 250° C. is specified as a preferable temperature range of the heating temperature , and the mold release film 10 having excellent embedding properties cannot be buried in the concave portion 223 , and the penetration of the adhesive agent from the adhesive layer 222 into the concave portion 223 cannot be sufficiently suppressed conventionally.

On the other hand, considering that in the present invention, when the target pressure is applied to FPC 200, the heating temperature of FPC 200 does not reach the target temperature, and the complex shear elastic modulus of release film 10 at 80° C. Set it below 1.00MPa. Therefore, the function as the release film 10 can be exhibited more reliably, and the release film 10 which has excellent embedding property can be embedded in the recessed part 223. Therefore, it is possible to reliably suppress or prevent the adhesive from the adhesive layer 222 from penetrating into the concave portion 223 .

Hereinafter, each layer which comprises the release film 10 is demonstrated. <Buffer layer 3> First, the buffer layer 3 will be described. This buffer layer 3 is arrange|positioned as the intermediate layer between the 1st mold release layer 1 and the 2nd mold release layer 2.

The buffer layer 3 is composed of a third thermoplastic resin composition. In the present invention, the third thermoplastic resin composition contains A plurality of thermoplastic resins are preferred.

Examples of combinations of thermoplastic resins include combinations of polyester resins and polyolefin resins, combinations of polyolefin resins, and combinations of polyamide resins and polyolefin resins. By selecting a combination of a polyester-based resin and a polyolefin-based resin, the complex shear modulus of the release film 10 at 80° C. can be relatively easily set to be below the aforementioned upper limit.

The polyester-based resin is not particularly limited, but examples include polyethylene terephthalate (PET), polycyclohexane terephthalate (PCT), polybutylene terephthalate (PBT), ), polyethylene naphthalate (PEN), polycyclohexane terephthalate, polytrimethylene terephthalate, etc., one or a combination of two or more of these can be used. In addition, when using these in combination of 2 or more types, this polyester-type resin may be these mixtures, and may be a copolymer. Among these, it is particularly preferable that the polyester-based resin is polybutylene terephthalate. Thereby, excellent followability with respect to the recessed part 223 can be provided to the buffer layer 3. Moreover, when polybutylene terephthalate is contained in the 1st thermoplastic resin composition which comprises the 1st mold release layer 1, the cushion layer 3 exhibits the adhesiveness outstanding to the 1st mold release layer 1.

Also, the polyolefin resin is not particularly limited, and examples thereof include polyethylene such as low-density polyethylene and high-density polyethylene, α-olefin-based polymers such as polypropylene, ethylene, propylene, butene , pentene, hexene, octene, etc. as polymer components, copolymers of ethylene and hexene, copolymers of ethylene and octene, copolymers of α-olefin and (meth)acrylate, ethylene and vinyl acetate An ester copolymer, an α-olefin-based copolymer such as a copolymer of ethylene and (meth)acrylic acid, or the like can be used alone or in combination of two or more kinds. Among these, at least one of a copolymer of ethylene and vinyl acetate (ethylene vinyl acetate copolymer) and a copolymer of ethylene and (meth)acrylic acid (ethylene (meth)acrylic acid copolymer) is preferred. Thereby, excellent followability with respect to the recessed part 223 can be provided to the buffer layer 3.

In the case of a combination of a polyester resin and a polyolefin resin, the content of the polyester resin in the third thermoplastic resin composition is preferably 5% by weight or more, 8% by weight or more and 20% by weight or more. The following is better. Thereby, excellent followability with respect to the recessed part 223 can be provided to the release film 10.

In addition, the melting point of the thermoplastic resin contained in the third thermoplastic resin composition is preferably less than 80°C, more preferably 40°C or higher and less than 80°C. Thereby, the complex shear elastic modulus at 80 degreeC of the release film 10 can be set relatively easily below the said upper limit value.

Also, in the third thermoplastic resin composition constituting the buffer layer 3, in addition to the aforementioned resin materials, crystal nucleating agents, antioxidants, slip agents, anti-adhesive agents, antistatic agents, and colorants may also be included. , stabilizers and other additives.

The storage elastic modulus E' at 150°C of the buffer layer 3 is preferably 9.0 MPa or more, more preferably 10 MPa or more and 50 MPa or less, still more preferably 10 MPa or more and 25 MPa or less. The storage elastic modulus E' of the buffer layer 3 at 150° C. is set as described above, so that when the release film 10 in the aforementioned step (2-2) is buried in the recess 223, a part of the buffer layer 3 is released from the release film 10 The edge portion of the film is exposed, and it is possible to reliably suppress or prevent adhesion to the FPC 200 . Therefore, contamination of FPC200 can be suppressed or prevented reliably. Moreover, the peeling of the release film 10 which pinches the edge part of the release film 10 in the said process (3) can be performed easily.

Furthermore, the storage elastic modulus E' of the buffer layer 3 at 150° C. can be obtained, for example, by preparing a buffer layer 3 with a width of 4 mm and a length of 20 mm in accordance with JIS K7244-4, and using a dynamic viscoelasticity measuring device (Hitachi "DMA7100" manufactured by Hi-Tech Co., Ltd.) was measured in tension mode, at a frequency of 1 Hz, and at a heating rate of 5° C./min.

In addition, the average thickness Tk of the buffer layer 3 is preferably not less than 60 μm and not more than 200 μm, more preferably not less than 70 μm and not more than 180 μm. Thereby, the effect acquired by setting the complex shear elastic modulus in 80 degreeC of the release film 10 below the said upper limit can be exhibited more remarkably.

＜1st release layer 1＞ Next, the first release layer 1 will be described. The first release layer 1 is laminated on one side of the buffer layer 3 .

The first release layer 1 has flexibility, and in the above-mentioned method of manufacturing the flexible printed circuit board 200 using the release film 10 , the first release layer 1 is in contact with the CL film 220 included in the FPC 200 Overlay the release film 10. Furthermore, in the aforementioned step (2-2) of this manufacturing method, when the superimposed flexible circuit board 210 and CL film 220 are bonded via the adhesive layer 222, the concave portion 223 formed by the flexible circuit board 210 and the CL film 220 is followed. The layer that is pressed into the shape and functions as a protection (cushion) material that prevents the release film 10 from breaking. Moreover, the 1st release layer 1 has a function as a contact layer for exhibiting the excellent release property of the release film 10 from the CL film 220 (FPC200) in said process (3).

Therefore, in the aforementioned step (2-2), penetration of the adhesive from the adhesive layer 222 into the concave portion 223 formed in the FPC 200 can be reliably suppressed or prevented. In addition, after forming the FPC 200 in which the flexible circuit board 210 and the CL film 220 are bonded via the adhesive layer 222 of the CL film 220 in the aforementioned step (2-2), in the aforementioned step (3), the mold release film When 10 is peeled off from FPC200, elongation and breakage in FPC200 can be suppressed or prevented reliably. Moreover, when the 3rd thermoplastic resin composition which comprises the cushion layer 3 contains a polyester resin, the 1st release layer 1 can exhibit the adhesiveness outstanding to the cushion layer 3.

The 1st mold release layer 1 is comprised from the 1st thermoplastic resin composition. In addition, the first thermoplastic resin composition is preferably composed of a composition that can set the storage elastic modulus E' of the first release layer 1 at 150° C. to 100 MPa or more, for example, it is better to mainly contain a polyester resin. good. Thereby, the said storage modulus E' can be set to 100 MPa or more relatively easily, and the said function can be given to the 1st release layer 1 reliably. In addition, it is relatively easy to impart the aforementioned functions to the release film 10 , that is, it is relatively easy to set the complex shear elastic modulus of the release film 10 at 80° C. to the aforementioned upper limit value or less.

Also, the polyester-based resin is not particularly limited, but for example, the same resins as those mentioned in the aforementioned third thermoplastic resin composition can be used, and among them, polybutylene terephthalate (PBT) is particularly preferable. . Thereby, the effect obtained by using a polyester resin can be exhibited more notably. Moreover, when polybutylene terephthalate is contained in the 3rd thermoplastic resin composition which comprises the buffer layer 3, the 1st release layer 1 which exhibits the outstanding adhesiveness with respect to the buffer layer 3 can be set.

Furthermore, when the first thermoplastic resin composition is mainly composed of polyester-based resins, it may contain thermoplastic resins other than polyester-based resins. Examples of such thermoplastic resins include polyethylene, polypropylene, polypropylene, - Polyolefin-based resins such as methyl-1-pentene, polystyrene-based resins such as syndiotactic polystyrene, and the like can be used alone or in combination of two or more kinds.

In addition, the first thermoplastic resin composition may contain at least one of inorganic particles and organic particles in addition to the aforementioned thermoplastic resins.

The inorganic particles are not particularly limited, but examples include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, boric acid Aluminum whiskers, boron nitride, crystalline silica, amorphous silica, antimony oxide, E glass, D glass, S glass, and the like can be used alone or in combination of two or more.

Also, the organic particles are not particularly limited, but examples include polystyrene particles, acrylic particles, polyimide particles, polyester particles, silicone particles, polypropylene particles, polyethylene particles, fluororesin particles and core-shell particles, etc., one of them can be used or two or more can be used in combination.

In addition, the average particle diameter of the inorganic particles and organic particles is preferably from 3 μm to 20 μm, more preferably from 5 μm to 20 μm. Thereby, when at least one of inorganic particles and organic particles is contained in the first thermoplastic resin composition, the surface of the surface of the first release layer 1 opposite to the buffer layer 3 can be relatively easily Roughness is set within the range described later.

When the first mold release layer 1 has unevenness on its surface, the 10-point average roughness (Rz) of the surface is preferably 0.5 μm or more and 3.6 μm or less, more preferably 1.0 μm or more and 3.5 μm or less . Thereby, when releasing the mold release film 10 from FPC200 (flexible circuit board 210), this mold release can be implemented with the excellent mold release property. In addition, the aforementioned 10-point average roughness (Rz) can be measured in accordance with JIS B 0601-1994.

The storage elastic modulus E' at 150°C of the first release layer 1 forming this structure is preferably 100 MPa or more, more preferably 100 MPa or more and 1000 MPa or less, and particularly preferably 100 MPa or more and 200 MPa or less. Thereby, the above-mentioned function can be provided reliably to the 1st mold release layer 1.

Furthermore, the storage elastic modulus E' at 150°C of the first release layer 1 can be obtained by preparing the first release layer 1 with a width of 4 mm and a length of 20 mm in accordance with JIS K7244-4, and using viscoelastic A measuring device (manufactured by Hitachi High-Tech Co., Ltd., "DMA7100") was used for measurement in tension mode, at a frequency of 1 Hz, and at a heating rate of 5° C./min.

Moreover, the average thickness T1 of the said 1st mold release layer 1 becomes like this. Preferably it is 5 micrometers or more and 30 micrometers or less, More preferably, it is 6 micrometers or more and 25 micrometers or less. Thereby, since the average thickness of the 1st mold release layer 1 is set in an appropriate range, the above-mentioned function can be given to the 1st mold release layer 1 more reliably.

Furthermore, as mentioned above, regarding the thickness of the first mold release layer 1, when the surface of the first mold release layer 1 opposite to the buffer layer 3 has a concave-convex shape, the thickness of the convex portion includes the convex portion. The thickness is measured at the positions of the recesses and the positions including the recesses, respectively.

Also, in the first thermoplastic resin composition constituting the first mold release layer 1, in addition to the above-mentioned resin material, inorganic particles, and organic particles, the same ones as those listed in the above-mentioned third thermoplastic resin composition may be included. additive.

＜Second release layer 2＞ Next, the second release layer 2 will be described. This 2nd mold release layer 2 is laminated|stacked on the other surface side of the cushion layer 3, ie, the surface side of the cushion layer 3 opposite to the 1st mold release layer 1.

The second mold release layer 2 has flexibility, and in the above-mentioned method of manufacturing the flexible printed circuit board 200 using the mold release film 10 , the first mold release layer 1 and the CL film 220 of the FPC 200 are laminated and released. film 10, and in the aforementioned step (2-2) of the manufacturing method, when the overlapping flexible circuit board 210 and CL film 220 are bonded via the adhesive layer 222, as the force from the heating and pressing plate 521 is transmitted to The layer of buffer layer 3 plays a role. Moreover, the 2nd mold release layer 2 has the function as a contact layer for exhibiting the excellent mold release property between the glass cloth 300 and the mold release film 10 in the said process (3).

The second release layer 2 is composed of a second thermoplastic resin composition, and the second thermoplastic resin composition is preferably selected so that the storage elastic modulus E' of the second release layer 2 at 150° C. can be set to 100 MPa or more. Specifically, the resin preferably mainly contains a polyester-based resin similarly to the aforementioned first thermoplastic resin composition. Thereby, the said storage elastic modulus E' can be set to 100 MPa or more relatively easily, and the said function can be given to the 2nd mold release layer 2 reliably. In addition, it is relatively easy to impart the aforementioned functions to the release film 10 , that is, it is relatively easy to set the complex shear elastic modulus of the release film 10 at 80° C. to the aforementioned upper limit value or less.

Also, the polyester-based resin is not particularly limited, but for example, the same resins as those mentioned in the aforementioned third thermoplastic resin composition can be used, and among them, polybutylene terephthalate (PBT) is particularly preferable. . Thereby, the effect obtained by using a polyester resin can be exhibited more notably.

Furthermore, when the second thermoplastic resin composition is mainly composed of polyester resin, it may contain thermoplastic resins other than polyester resin. The same resins are cited.

In addition, the second thermoplastic resin composition may contain at least one of inorganic particles and organic particles in addition to the aforementioned thermoplastic resins.

The inorganic particles and organic particles are not particularly limited, but the same particles as those mentioned in the above-mentioned first thermoplastic resin composition can be used.

The storage elastic modulus E' at 150°C of the second release layer 2 forming this structure is preferably 100 MPa or more, more preferably 100 MPa or more and 1000 MPa or less. Thereby, the above-mentioned function can be provided reliably to the 2nd mold release layer 2.

Moreover, the average thickness T2 of the said 2nd mold release layer 2 becomes like this. Preferably it is 5 micrometers or more and 30 micrometers or less, More preferably, it is 6 micrometers or more and 25 micrometers or less. Thereby, the above-mentioned function can be given to the 2nd mold release layer 2 more reliably.

In addition, in the second thermoplastic resin composition constituting the second mold release layer 2, in addition to the above-mentioned resin material, inorganic particles, and organic particles, the same ones as those listed in the above-mentioned third thermoplastic resin composition may be included. additive.

In addition, in the first mold release layer 1 and the second mold release layer 2, the first thermoplastic resin composition and the second thermoplastic resin composition may be the same or different, but from the viewpoint of substitutability, preferably are the same or of the same nature. Moreover, in the 1st mold release layer 1 and the 2nd mold release layer 2, the average thickness may be the same, and may differ.

In the release film 10 having the structure of laminating the first release layer 1, buffer layer 3, and second release layer 2 as described above, the average thickness Tt thereof is preferably 90 μm or more and 250 μm or less, more preferably 100 μm or more And 220μm or less. Thereby, the effect acquired by setting the complex shear elastic modulus in 80 degreeC of the said release film 10 below the said upper limit can be exhibited more reliably.

Here, as mentioned above, the complex shear elastic modulus of the mold release film 10 at 80° C. may be 1.00 MPa or less, preferably 0.65 MPa or less. By setting the complex shear modulus of the release film 10 at 80° C. as described above, it is possible to more reliably suppress or prevent the adhesive from the adhesive layer 222 from penetrating into the concave portion 223 .

Moreover, the storage shear elastic modulus of the release film 10 at 80° C. is preferably 1.00 MPa or less, more preferably 0.60 MPa or less. In addition, the loss shear modulus of the release film 10 at 80° C. is preferably 0.40 MPa or less, more preferably 0.25 MPa or less. By separately setting the storage shear modulus and loss shear modulus of the release film 10 at 80° C. as described above, it is possible to more reliably suppress or prevent the adhesive from the adhesive layer 222 from penetrating into the recess 223 .

The complex shear modulus, storage shear modulus and loss shear modulus of the release film 10 at 80°C can be obtained as follows: The release film 10 having a circular shape in plan view was measured at a frequency of 10 Hz, a strain of 0.1%, and a heating rate of 4° C./min using a viscoelasticity measuring device (manufactured by Anton Paar, “MCR102”).

Furthermore, in the present embodiment, the release film 10 is composed of a laminate in which the first release layer 1, the buffer layer 3, and the second release layer 2 are sequentially laminated, but it is not limited to this structure. It is a laminate configuration including an intermediate layer such as an adhesive layer arranged between the first release layer 1 and the buffer layer 3 and at least one of the second release layer 2 and the buffer layer 3 .

Also, if the release film 10 can maintain excellent release properties between the glass cloth 300 and the release film 10 in the aforementioned step (3), the second release layer 2 in contact with the glass cloth 300 can be omitted.

As mentioned above, although the manufacturing method of the release film of this invention and a molded article was demonstrated, this invention is not limited to these.

For example, in the above-mentioned embodiment, the case where the release film of the present invention is applied to the press molding method of laminating two layers of flexible printed circuit boards disposed between heating and cooling plates has been described. The number of laminated flexible printed circuit boards is not limited to two layers, and may be one layer or three or more layers.

In addition, although the mold release film of the present invention is applied to the case of pressurizing a flexible printed circuit board arranged between heating and cooling plates using a press molding method, it is not limited thereto. Pressurization can be performed using, for example, a roll-to-roll pressing machine, and further can also be performed using a vacuum pressure forming method. [Example]

Hereinafter, the present invention will be described in detail based on examples, but the present invention is not limited thereto.

1. Preparation of raw materials The following materials were prepared as raw materials for manufacturing the release film.

• Thermoplastic resin material Low-density polyethylene (LDPE, manufactured by Ube Maruzen Co., Ltd., "R300") Ethylene vinyl acetate copolymer (EVA, manufactured by DOW-MITSUI POLYCHEMICALS, "P1403") Ethylene-vinyl acetate copolymer (EVA, manufactured by DOW-MITSUI POLYCHEMICALS, "EV360") Ethylene vinyl acetate copolymer (EVA, manufactured by DOW-MITSUI POLYCHEMICALS, "V5274") Ethylene methyl methacrylate copolymer (EMMA, manufactured by Sumitomo Chemical Co., Ltd., "WH102") Ethylene methyl acrylate copolymer (EMA, manufactured by SK Chemicals, "29MA03") Ethylene methyl acrylate copolymer (EMA, manufactured by Nippon Polyethylene Co., Ltd., "EB050S") Polybutylene terephthalate (PBT, manufactured by Changchun Petrochemical Company, "1100-630S") Copolymerized polybutylene terephthalate (PBT, manufactured by Mitsubishi Engineering Plastics Corporation, "5505S") Polypropylene (PP, manufactured by Sumitomo Chemical Co., Ltd., "FH1016") Adhesive polyolefin (AD, manufactured by Mitsubishi Chemical Corporation, "F515A")

2. Manufacture of release film <Example 1> First, as the first thermoplastic resin composition and the second thermoplastic resin composition, 70 parts by weight of polybutylene terephthalate (PBT, 1100-630S) and copolymerized polybutylene terephthalate (PBT, 5505S) composition consisting of 30 parts by weight. Also, as the third thermoplastic resin composition, 40 parts by weight of ethylene vinyl acetate copolymer (EVA, EV360), 35 parts by weight of ethylene methyl methacrylate copolymer (EMMA, WH102), polybutylene terephthalate A composition consisting of 10 parts by weight of diester (PBT, 1100-630S) and 15 parts by weight of polypropylene (PP, FH1016).

Next, the first release layer 1 was obtained by forming a film by extrusion T-die method using the first thermoplastic resin composition.

Next, the first release layer 1 is sequentially formed into films using the extrusion T-die method using the third thermoplastic resin composition and the second thermoplastic resin composition, thereby forming a buffer layer on the first release layer 1 3 and the second release layer 2 were sequentially laminated to obtain the release film 10 of Example 1.

In addition, in the obtained release film 10, the average thickness T1 of the 1st release layer 1 was 15 micrometers, the average thickness Tk of the buffer layer 3 was 80 micrometers, and the average thickness T2 of the 2nd release layer 2 was 15 micrometers.

Also, for the release film 10, the complex shear elasticity at 80°C was measured at a frequency of 10 Hz, a strain of 0.1%, and a heating rate of 4°C/min using a viscoelasticity measuring device (manufactured by Anton Paar, "Product No. MCR102"). Modulus, storage shear modulus and loss shear modulus, the results were 0.63MPa, 0.59MPa and 0.21MPa.

In addition, for the first mold release layer 1 and the buffer layer 3, each measured at 150° C. using a dynamic viscoelasticity measuring device (“DMA7100” manufactured by Hitachi High-Tech Co., Ltd.) in tension mode, frequency 1 Hz, and heating rate 5° C./min. Under the storage elastic modulus E', the result is 180MPa and 16MPa.

Also, for the first release layer 1, the average roughness of 10 points on the surface exposed on the side opposite to the buffer layer 3 was measured using a surface roughness measuring device (manufactured by Mitutoyo Corporation, "SURFTST SJ-210") ( Rz), the result was 2.7 μm.

<Example 2, Comparative Examples 1~4> The compositions shown in Table 1 were used as the first thermoplastic resin composition, the second thermoplastic resin composition, and the third thermoplastic resin composition, and the first mold release layer 1 and buffer layer having the average thicknesses shown in Table 1 were formed. 3 and the second release layer 2, in the same manner as in Example 1 above, the complex shear elastic modulus of the release film 10 at 80°C was obtained as shown in Table 1 in Example 2, Release film 10 of Comparative Examples 1-4.

3. Evaluation The following evaluations were performed about the mold release film 10 of each Example and each comparative example, respectively.

3-1. Landfill performance of release film The mold release film 10 of each Example and each comparative example was made into width 270 mm, respectively. In addition, it is assumed that a cover film 220 (manufactured by Arisawa Manufacturing Co., Ltd., "CMA0525") is attached to the flexible circuit board 210 so that the adhesive layer 222 included in the cover film 220 is formed on the flexible circuit board 210 side. After FPC200 (laminated body) with pitch 50 μm, width 50 μm, and height 18 μm of unevenness, release film 10 is pressed into FPC200 laminated with 2 layers as shown in FIG. 1 under the conditions of 180°C, 3MPa, and 15 minutes. Then, in the state of the laminate of FPC200 and release film 10 , the laminate is cut (sheared) in the thickness direction, and one end of release film 10 is held to peel off release film 10 . The maximum infiltration amount of the adhesive agent in the concave part of FPC200 in planar view at the time of pinching and peeling off one end of the release film 10 was measured, and evaluated according to the following criteria.

[evaluation criteria] A: The maximum infiltration amount is less than 55 mm. B: The maximum infiltration amount is 55 or more and less than 65 mm. C: The maximum infiltration amount is 65 or more.

3-2. Peelability of release film The release film 10 of each example and each comparative example was set to have a width of 270 mm, and the cover film 220 (manufactured by Arisawa Manufacturing Co., Ltd., "CMA0525") was adhered to the flexible circuit board 210 to cover the flexible circuit board 210. After forming the adhesive layer 222 of the film 220 as the flexible circuit board 210 side, FPC 200 (laminated body) having irregularities with a pitch of 50 μm, a width of 50 μm, and a height of 18 μm was formed at 180° C., 3 MPa, and 15 minutes. The release film 10 is press-fitted into the FPC 200 laminated with two layers as shown in FIG. 1 . Then, the ease of peeling (release property) of the release film 10 when one end of the release film 10 was pinched and peeled was evaluated according to the following criteria.

[evaluation criteria] A: When peeling off a release film, peeling was possible. B: When the release film was peeled off, the buffer layers were fused together and it was difficult to peel off.

3-3. Summary Table 1 shows the evaluation results obtained in the above-mentioned 3-1. Embedding property of the release film and the above-mentioned 3-2. Release property of the release film.

[Table 1] Example comparative example 1 2 1 2 3 4 Release film 10 1st release layer 1 (1st) thermoplastic resin composition Polybutylene terephthalate (PBT 1100-630S)[wt%] 70 70 100 70 70 70 Copolymerized polybutylene terephthalate (PBT 5505S) [wt%] 30 30 30 30 30 Average roughness of 10 points on the surface (Rz) (μm) 2.7 2.9 3.5 2.5 2.8 2.5 Average thickness T1(μm) 15 15 15 15 15 15 buffer layer 3 (3rd) thermoplastic resin composition Low-density polyethylene (LDPE R300) [wt%] 50 35 Ethylene vinyl acetate copolymer (EVA P1403) [wt%] 20 Ethylene vinyl acetate copolymer (EVA EV360) [wt%] 40 100 Ethylene methyl methacrylate copolymer (EMMA WH102) [wt%] 35 35 Ethylene vinyl acetate copolymer (EVA V5274) [wt%] 45 Ethylene methyl acrylate copolymer (EMA 29MA03) [wt%] 40 Ethylene methyl acrylate copolymer (EMA EB050S) [wt%] 40 Polybutylene terephthalate (PBT 1100-630S)[wt%] 10 10 15 15 10 Polypropylene (PP FH1016) [wt%] 15 15 20 15 Adhesive polyolefin (AD F515A) [wt%] 15 20 Average thickness Tk(μm) 80 80 80 80 80 80 1st release layer 2 (2nd) thermoplastic resin composition Polybutylene terephthalate (PBT 1100-630S)[wt%] 70 70 100 70 70 70 Copolymerized polybutylene terephthalate (PBT 5505S) [wt%] 30 30 30 30 30 Average thickness T2(μm) 15 15 15 15 15 15 Complex shear elastic modulus (MPa) of release film 10 at 80°C 0.63 0.60 1.19 1.05 1.06 <0.1 Storage shear elastic modulus (MPa) of release film 10 at 80°C 0.59 0.57 1.09 1.01 1.01 <0.1 Loss shear elastic modulus (MPa) of release film 10 at 80°C 0.21 0.19 0.49 0.29 0.33 <0.1 Storage elastic modulus E'(MPa) of buffer layer 3 at 150°C 16 14 16 twenty one 12 <0.1 Storage elastic modulus E'(MPa) of the first release layer 1 at 150°C 180 180 180 190 180 190 Average thickness Tt (μm) of release film 10 110 110 110 110 110 110 evaluate Embedding properties of release film 10 A B C C C A Release property of release film 10 A A A A A B

As shown in Table 1, the following results are shown. In each example, the complex shear elastic modulus of the release film 10 at 80° C. was set to be 1.00 MPa or less. As a result, penetration of the adhesive into the recess 223 was suppressed. .

On the other hand, the following results were shown. In each of the comparative examples, the complex shear modulus of the release film 10 at 80° C. could not be set to 1.00 MPa or less, so the penetration of the adhesive into the concave portion 223 was clearly confirmed. . [Industrial availability]

According to the present invention, it is possible to obtain a release film that exhibits excellent embedding properties in recesses. Therefore, when the release film is used to form, for example, a flexible printed circuit board using a flexible circuit board and a cover film, the release film having excellent embedding properties can be embedded in the flexible printed circuit board formed on the flexible circuit board and the cover film. The concave part of the printed circuit board. Therefore, when the concave portion is formed on the flexible printed circuit board, it is possible to reliably suppress or prevent the adhesive from penetrating into the formed concave portion from the adhesive layer included in the cover film. Therefore, the present invention has industrial applicability.

1: The first release layer 2: The second release layer 3: buffer layer 10: Release film 10A: Release film 10B: Release film 200: Flexible Printed Circuit Board (FPC) 210: flexible circuit substrate 220: Covering film (CL film) 221: Overlay 222: Adhesive layer 223: Concave 300: glass cloth 300A: glass cloth 300B: glass cloth 521: Heated crimping plate T1: Average thickness of the first release layer T2: Average thickness of the second release layer Tk: the average thickness of the buffer layer Tt: Average thickness of release film

[FIG. 1] It is a longitudinal cross-sectional view for explaining the manufacturing method of the flexible printed circuit board in the state which manufactures a multilayer. [Fig. 2] (a) to (c) are longitudinal cross-sectional views showing each step in a method of manufacturing a flexible printed circuit board in a multilayered state. [ Fig. 3 ] is a longitudinal sectional view showing an embodiment of the release film of the present invention. [ Fig. 4 ] is a partially enlarged longitudinal sectional view obtained by partially enlarging part A of the release film shown in Fig. 3 .

1: The first release layer

2: The second release layer

3: buffer layer

T1: Average thickness of the first release layer

T2: Average thickness of the second release layer

Tk: the average thickness of the buffer layer

Tt: Average thickness of release film

Claims (14)

A release film having a first release layer made of a first thermoplastic resin composition and a buffer layer made of a third thermoplastic resin composition, characterized in that, The complex shear elastic modulus at 80° C. of the release film is 1.00 MPa or less. Such as the release film of claim 1, wherein, The storage elastic modulus at 150° C. of the buffer layer is 9.0 MPa or more. Such as the release film of claim 1 or 2, wherein, The storage shear elastic modulus at 80° C. of the release film is 1.00 MPa or less. Such as the release film of claim 1 or 2, wherein, The loss shear elastic modulus at 80° C. of the release film is 0.40 MPa or less. Such as the release film of claim 1 or 2, wherein, In this 1st mold release layer, 10 point average roughness Rz of the surface of the side opposite to this buffer layer is 0.5 micrometer or more and 3.6 micrometers or less. Such as the release film of claim 1 or 2, wherein, The storage elastic modulus E' at 150°C of the first release layer is 100 MPa or more. Such as the release film of claim 1 or 2, wherein, The first thermoplastic resin composition contains a polyester resin as a main material. Such as the release film of claim 1 or 2, wherein, The buffer layer has an average thickness of not less than 60 μm and not more than 200 μm. Such as the release film of claim 1 or 2, wherein, The average thickness of this 1st mold release layer is 5 micrometers or more and 30 micrometers or less. Such as the release film of claim 1 or 2, wherein, The third thermoplastic resin composition contains a plurality of thermoplastic resins, and the melting point of the thermoplastic resin is less than 80°C. Such as the release film of claim 10, wherein, The third thermoplastic resin composition contains a polyester resin and a polyolefin resin as the thermoplastic resin. Such as the release film of claim 1 or 2, wherein, This mold release film has the 2nd mold release layer which consists of a 2nd thermoplastic resin composition laminated|stacked on the side opposite to this 1st mold release layer of this buffer layer. Such as the release film of claim 1 or 2, wherein, This release film is used to form circuits. A method of manufacturing a molded article, comprising disposing the release film on the object in such a manner that the first release layer of the release film according to any one of claims 1 to 13 becomes the object side step and the step of heating and pressing the object on which the release film is arranged, and in the step of arranging the release film, the surface of the object on which the release film is arranged is composed of semi-cured Made of thermosetting resin material.

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