KR102240918B1 - Insulation film and method of manufacturing insulation film - Google Patents

Abstract

The present invention is a thin film coating comprising a carrier film and an insulating resin using the same to form an insulating layer, and a semi-cured (B-stage) adhesive layer on one side thereof. Regarding a thin-film-coated insulating film having a filling rate of 75% or more and an elastic modulus of 15g.f/㎠ or less in a printed circuit wiring part by coating an insulation film and a resin solution having an insulating function and an adhesive function on one side of a carrier film. will be.

Description

Insulation film and method of manufacturing insulation film {INSULATION FILM AND METHOD OF MANUFACTURING INSULATION FILM}

The present invention relates to an insulating film and a method of manufacturing the same, and to a thin film coated insulating film having excellent step fillability and a low elastic modulus of a printed circuit, and a method of manufacturing the same.

In recent years, miniaturization and slimming of electronic devices are accelerating, and in this trend, high-functionalization in which various functions are integrated is rapidly developing. Accordingly, the printed circuit board used in electronic devices is required to be miniaturized (reduced line width), integrated, and lightweight. In addition, the printed circuit board complexly includes a rigid printed circuit board, a flexible printed circuit board (FPCB), and a touch & display module according to its physical characteristics. The reason for using a variety of printed circuits is to connect or stack each function due to the effect of high-function integration, which is becoming slimmer. A flexible printed circuit board or a flexible printed circuit cable is used to connect a module having individual functions and a laminated printed circuit board to each other. Polyimide Film is used as an insulating layer to protect the circuit of the associative circuit board, and a coverlay coated with a thermosetting adhesive is used on one side of the insulating layer. Existing PI film-type coverlays have low level fillability in highly integrated microcircuit flexible printed circuit boards (FPCBs), resulting in deelamination during soldering, and corrosion of printed circuits due to plating solution and cleaning solution penetrating into the terminals There is a problem that the durability of the product is deteriorated. In addition, the stress of the PI film may cause a short circuit in the cable connected by ACF (Anisotropic Conductive Film). In addition, in the assembly process of the miniaturized and slimmed module, there is a problem of low productivity in the assembly process due to the elasticity of the film type coverlay. To solve this problem, currently, a punched PI film-type coverlay is formed by heat press, and a flexible insulating paste is printed and cured to insulate it. , Thickness control, insulation paste cracking problems. There is a problem that productivity is lowered by the above process.

Accordingly, an object of the present invention is to produce a problem of corrosion of the printed circuit due to the low level filling property by using films such as the conventional PI film, and the plating liquid and the cleaning liquid penetrating the terminal portion, while causing the stress of the PI film. Insulation paste, which causes problems such as liquid splash, liquid flow, thickness control, insulation paste cracking, and productivity reduction, is not used, without using conventional films such as PI film, which cause short circuit and decrease in productivity. It is to provide an insulating film and a method of manufacturing the same.

Thus, by forming an insulating layer by coating a resin solution using a carrier film and laminating a semi-curable adhesive layer by coating on one side to produce a thin-film coated insulating film, it has excellent step fillability and low elastic modulus of printed circuits. It is to provide a thin-film coated insulating film and a method of manufacturing the same. In addition, it is possible to shorten the manufacturing process of printed circuits by manufacturing the folded part in a single process of laminating coverlays without using insulation paste. By not using insulation paste, liquid splash defects in the insulation paste printing process and liquid flow during thermal curing , To provide an insulating film and a method of manufacturing the same that can prevent defects due to the problem of cracks after curing.

On the other hand, the present invention improves durability by improving the step fillability and minimizing the stress due to elasticity by developing a coverlay for protecting printed circuits that are used in combination in electronic devices that are miniaturized, slipped, and highly integrated as a thin-film coated product. It is intended to provide ease of module assembly.

In addition, the present invention prevents reverse bending and warpage in a specific layer in a composite laminated printed circuit board, and has excellent filling properties to reduce noise in high-speed signal transmission, thereby reducing signal integrity and RFI ( Radio Frequency Interference).

In order to achieve the above object, the present invention is a carrier film; An insulating layer formed on one surface of the carrier film; An adhesive layer formed on the insulating layer; And it provides a thin film coated insulating film having a low elastic modulus and excellent step fillability of a printed circuit including a protective film formed on the adhesive layer, and a method of manufacturing the same.

The present invention also includes the steps of (a) forming an insulating layer on a carrier film; (b) forming an adhesive layer on the insulating layer; And (c) laminating a protective film on the adhesive layer. It provides a thin-film-coated insulating film having excellent step fillability and a low elastic modulus of a printed circuit, and a method of manufacturing the same.

According to the present invention, unlike the prior art, which used PI film or insulating paste in the past, the PI film or insulating paste is not used, but an insulating layer is coated by coating an insulating resin using a carrier film and the same. ), and coated on one side of the carrier film with a thin-film-coated insulating film containing an adhesive layer in a semi-cured (B-stage) state and a resin solution having an insulating function and an adhesive function on one side of the carrier film. Thus, there is provided a thin film coated insulating film having excellent step fillability and low elastic modulus of a printed circuit, and a method of manufacturing the same.

In addition, according to the present invention, there is provided a thin-film-coated insulating film having a filling rate of a printed circuit wiring part of 75% or more and an elastic modulus of 15 g.f/cm 2 or less, and a low elastic modulus of a printed circuit. .

Specifically, according to the present invention, the thin film-coated insulating film has excellent filling properties in the steps of the metal circuit, so that the plating solution does not penetrate into the circuit and the plating cleaning solution does not penetrate into the circuit during the plating process of the microcircuit, so that the terminal part is not lifted and solder (Solder). Delamination due to heat in the process can be prevented. In addition, unlike films such as a conventional PI film, the thin film coated insulating film according to the present invention can be applied to a printed circuit board that requires low elasticity due to its low stress characteristic. In addition, according to the present invention, by laminating a thin-film coated insulating film with low elasticity, the process can be shortened by manufacturing the folded portion in a single process of laminating a coverlay without using an insulating paste. It is possible to prevent defects due to poor liquid splashing, liquid flow during thermal curing, and cracks after curing.

1 shows the structure of a thin film coated insulating film of the present invention.
Figure 2 shows a method of manufacturing a thin-film coated insulating film using the carrier film of the present invention (lamination manufacturing).
Figure 3 shows a method of manufacturing a thin-film coated insulating film using the carrier film of the present invention (laminate manufacturing).
4 shows a method of laminating a flexible printed circuit board (FPCB) of the thin film coated insulating film of the present invention.
5 shows the environmental reliability observation results of Experimental Example 2.
6 shows the results of chemical resistance evaluation of Experimental Example 3.
7 shows the step crack evaluation results of Experimental Example 4.
8 shows the result of evaluating the step filling property of Experimental Example 6.
9 shows the method and result of evaluating the flexibility of Experimental Example 7.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by an expert skilled in the art to which the present invention belongs. In general, the nomenclature used in this specification is well known and commonly used in the art.

Specific structural or functional descriptions presented in the embodiments of the present invention are exemplified only for the purpose of describing the embodiments according to the concept of the present invention, and embodiments according to the concept of the present invention may be implemented in various forms. In addition, it should not be construed as being limited to the embodiments described in the present specification, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

The present invention will be described in detail a thin film coated insulating film having excellent metal step filling properties and low stress of a printed circuit, and a method of manufacturing the same.

Existing coverlay films are generally used for the purpose of protecting wiring parts, and are manufactured by laminating a film (insulation layer) using a synthetic resin such as polyimide resin and an adhesive layer. Such a film-type coverlay is used by putting an adhesive layer of the coverlay on the wiring portion of a printed circuit board (PCB) and laminating it using a heat press. The conventional coverlay uses a film substrate as an insulating layer, so the space filling rate between the printed circuit wiring is low. Due to the low level of filling due to the thickness of the wiring, a plating solution or a cleaning solution penetrates the gap, causing corrosion of the circuit pattern or being lifted during soldering. In addition, it is difficult to manufacture a thin film and the price is high because limited materials are inevitably used. In addition, the existing coverlay using PI film has high elasticity, so additional processing is required using insulating paste when necessary, and processing defects due to this also appear.

In the present invention, a thin film coated insulating film having higher productivity, lower cost, and excellent physical properties than the insulating film is manufactured by using a carrier film as an insulating layer without using an insulating film.

The carrier film used in the present invention is used as a substrate for coating the insulating resin solution, and is used for curing and drying the insulating resin layer of the thin film. In addition, when the manufactured thin film coated insulating film is attached to protect the wiring of the printed circuit, it serves as a position guide, and thus may serve as a guide so that the thin film coated insulating film can be laminated at a predetermined position without creases.

The present invention, in one aspect, a carrier film; An insulating layer formed on one surface of the carrier film; An adhesive layer formed on the insulating layer; And it relates to a thin-film coated insulating film comprising a protective film formed on the adhesive layer (Fig. 1). Here, the thin film coated insulating film may use a carrier film as a coverlay.

The present invention also includes the steps of (a) forming an insulating layer on a carrier film; (b) forming an adhesive layer on the insulating layer; And (c) laminating a protective film on the adhesive layer. It relates to a method of manufacturing a thin-film coated insulating film having excellent fillability and low elastic modulus. Here, the thin film coated insulating film may use a carrier film as a coverlay.

The thin film-coated insulating film of the present invention has a filling rate of 75% or more by manufacturing an insulating film using a carrier film coated with an insulating layer directly on the surface, that is, by manufacturing an insulating film without using films such as PI film. It has excellent filling properties and low stress, so the elastic modulus is less than 15g.f/㎠, which is a key technical feature.

If the formed metal circuit space is not filled with an insulator, the plating solution and washing solution permeate into the edge space of the circuit part during the plating process, causing vaporization and expansion in the SMT (Surface Mount Technology) process, causing the coverlay to be lifted. Even if there is no lift, the metal circuit is oxidized due to the infiltrated liquid, causing a problem in the durability of the product.

The above problems appearing in the PCB manufacturing process appear due to various factors such as the shape and thickness of a metal circuit, a circuit line width, and a circuit space. Therefore, it is necessary to fundamentally solve the above problem. The filling rate of the metal circuit space of the coverlay using the PI film was less than 60%. Through the present invention, when the space filling rate was 75% or more, it was confirmed that the above-described lifting or liquid penetration in the plating process did not appear.

Meanwhile, a work of connecting a display panel or a touch panel to the FPCB with an anisotropic conductive film (ACF) is performed. In particular, due to the recent demand for high resolution, thin film, and light weight of the display, the adhesion area of ACF has been reduced due to the miniaturized circuit, resulting in relatively low adhesion, and the process conditions were also manufactured under low temperature and low pressure conditions than before, resulting in lower adhesion. In case of using FPCB with high elasticity, short-circuit can occur more easily due to external impact. Therefore, insulating paste with low elastic modulus is printed on the bend with a screen printer to lower the elasticity, thereby compensating the reliability of ACF attachment. Currently used insulating pastes are usually used with a dry thickness of 25 to 30 µm, and the modulus of elasticity is 16 g.f/cm 2 to 18 g.f/cm 2 when the insulating paste thickness is 30 µm. Accordingly, in the present invention, the insulating film is characterized in that it has a modulus of elasticity of 15g.f/cm2. Insulation film with low elastic modulus replaces the process of laminating a coverlay of existing PI film and then applying insulating paste to produce a flexible printed circuit with a low elastic modulus in a single process, reducing process cost and improving manufacturing yield. Cost can be reduced and the durability of the product can be improved.

In the present invention, the insulating layer may be characterized in that it is formed by a coating method using the carrier film.

In the present invention, the adhesive layer may be characterized in that it is manufactured by directly laminating an adhesive resin on the insulating layer or by forming an adhesive layer on another film having releasability and laminating it with the insulating layer (Figs. 2 and 3). .

In the present invention, the carrier film is a PET film, semi-matt PET film, matt PET film, PEN film, PES film, TPU film, nylon (Nylon) film, PVC film, synthetic paper and synthetic It may be characterized in that at least one selected from the group consisting of resin coated paper, but is not limited thereto. Preferably, the price is low and various kinds of PET films can be used. In addition, both the release-coated and untreated surfaces of the carrier film may be used. The presence or absence of surface treatment of the carrier film is selected according to the removability of the carrier film after temporary bonding or hot pressing. In addition, the thermal deformation rate of the carrier film should be less than 1% under the hot pressing conditions (60 minutes, 150°C, 30 kg/cm ^{2 ).} If the thermal strain is higher than this, there is a problem in that the punched thin film coated insulating film cannot be adhered to the correct position due to dimensional defects, and when the carrier film is removed after heat press, it adheres to the insulating resin and the peeling force is increased or peeling is not possible.

In the present invention, it may be characterized in that the thickness of the carrier film is preferably 20 to 125 μm. When the thickness is less than 20 μm, it is difficult to laminate according to the punching position due to bending or folding when stacking a thin film coated insulating film on a printed circuit, and there is a problem of occurrence of wrinkles due to the thin film. In addition, when the thickness exceeds 125 μm, there is a problem in the filling of metal circuits after heat pressing, and there is a problem of edge burr defects in the cutting part in the punching process of the thin-film coated insulating film.

In the present invention, the carrier film is removed after temporary bonding or hot pressing and applied as a coverlay of a printed circuit board (PCB) (FIG. 4).

According to the present invention, by using a carrier film, a variety of polymer insulating materials can be used without using an expensive polyimide film, and thus, there are advantages in productivity and price.

In the present invention, it may be characterized in that the thickness of the insulating layer is preferably 2 to 12 μm. If the thickness is less than 2㎛, tearing appears after heat pressing at the stepped portion of the metal wiring in the printed circuit, and if the thickness exceeds 12㎛, the problem of lowering the filling of the stepped portion of the metallization part occurs, and the curing time according to the thickness increase is long, resulting in lower productivity. The amount of coating of insulating resin solution increases the price.

In the present invention, the insulating layer may be characterized in that it is made of at least one selected from the group consisting of a thermoset resin, a thermoplastic resin, and a photocurable resin. Specifically, the insulating layer is an epoxy resin, polyurethane resin, polyester resin, polyimide resin, amide resin, phenoxy resin (phenoxy resin). resin), noblock resin, melamine resin, celluloid acetate resin, alkyd resin, rosin ester resin, maleic resin, It may be characterized in that it is made of at least one selected from the group consisting of ethylene acrylate resin, urethane acrylate resin, epoxy acrylate resin, and modified resins thereof, It is not limited thereto.

In the present invention, flame retardants, surfactants, adhesion promoters, and the like may be used for the insulating layer resin. As a flame retardant, phosphorus-based flame retardants such as TEP (Triethyl phosphate), RDP (Resorcinol bis (diphenyl phosphate), TCP (Tricresyl phosphate), IPPP (Isopropylphenyl phosphate)), or MCA (Melamine cyanurate), ATO (Aluminium trioxide), ATH (Aluminium Inorganic flame retardant such as trihydrate), etc. In the present invention, flame retardant is secured by using a flame retardant of 15% compared to resin, and a silicone-based surfactant for preventing pinholes and leveling properties of the coating film when coated on a carrier film. A silane-based coupling agent or a triazine derivative can be used to improve the adhesion between layers of printed circuits.

In the present invention, the adhesive layer may be characterized in that it is in a semi-cured (B-stage) state. The adhesive layer must be semi-cured after coating drying, and must be fully cured (C-stage) by heat press after being laminated with a printed circuit.

In the present invention, the adhesive layer may be made of a resin that is the same as or different from that of the insulating layer resin.

In the present invention, the adhesive layer may include an adhesion promoter and a surfactant to improve the function of the adhesive layer.

In the present invention, it may be characterized in that the thickness after drying the coating of the adhesive layer is preferably 3 to 30 μm. If the thickness is less than 3 μm after drying, there is a problem in that the resin flow is low in the heat press process, so that the filling of the steps of the circuit wiring is low, and the adhesion to the printed circuit part is low. On the other hand, when the dry thickness of the adhesive layer exceeds 30 μm, there is a problem that contamination of the plated terminal portion and non-plating occur due to excessive resin flow in the heat press process.

In the present invention, the insulating layer and the adhesive layer may be characterized in that formed by a single coating using a carrier film.

[Example]

Hereinafter, the present invention will be described in more detail through examples. These examples are for illustrative purposes only, and it will be apparent to those of ordinary skill in the art that the scope of the present invention is not construed as being limited by these examples. Therefore, it will be said that the practical scope of the present invention is defined by the appended claims and their equivalents.

Preparation Example 1: Preparation of Insulation Composition 1

Put 40 parts by weight of cyclohexanone into a 10-liter container equipped with a stirrer, and put 20 parts by weight of polyimide modified resin (HPC-9000-21, Hitachi Chemical) and 30 parts by weight of aluminum hydroxide (OSDH-3, Ohsung Corporation). After stirring for 10 minutes, 10 parts by weight of a dispersant (BYK-167, Bayer) was added and stirred for 30 minutes to make a mixed solution. Then, use a basket mill (DWS-25, Daewon Stech) containing zirconia beads (Zirconia bead particle diameter 5㎛). Disperse for 40 minutes at 1,500 rpm. The dispersion solution 1 was prepared by filtering the dispersed solution with SUS#1000 mesh.

20 parts by weight of the prepared dispersion 1 was added to a container equipped with a stirrer, 50 parts by weight of a polyimide modified resin (HPC-9000-21, Hitachi Chemical) and 19.5 parts by weight of cyclohexanone were added, and the mixture was stirred for 20 minutes. 10 parts by weight of a modified resin (Arakid-9201N, Arakawa Chemical) and 0.5 parts by weight of a leveling agent (BYK 307, Bayer) were added and stirred for 1 hour. The completely mixed solution was filtered with SUS#1000 mesh to prepare insulating composition 1.

Preparation Example 2: Preparation of Insulation Composition 2

Put 30 parts by weight of dimethyl acetamide in a 10-liter container equipped with a stirrer and 10 parts by weight of polyimide modified resin (Torlon Al-30, Solvay) and 30 parts by weight of aluminum hydroxide (OSDH-3, Ohsung Corporation). After stirring for a minute, 10 parts by weight of a dispersant (BYK-167, Bayer) was added and stirred for 40 minutes to make a mixed solution. Then, use a basket mill (DWS-25, Daewon Stech) containing zirconia beads (Zirconia bead particle diameter 5㎛) to 1,500 Disperse at rpm for 60 minutes. The dispersion solution 2 was prepared by filtering the dispersed solution with SUS#1000 mesh.

In a container equipped with a stirrer, 10 parts by weight of N-methyl pyrrolidone and 44.5 parts by weight of dimethyl acetamide were added, and 20 parts by weight of a polyimide modified resin (Torlon Al-30, Solvay) was added. After stirring for a minute to completely dissolve, 20 parts by weight of the dispersion 2 was added and 5 parts by weight of an epoxy modified resin (YDCN-500-8P, Kukdo Chemical) was added while stirring, and 0.5 parts by weight of a leveling agent (BYK 307, Bayer) was added and stirred for 90 minutes. . The completely mixed solution was filtered with SUS#1000 mesh to prepare insulating composition 2.

Preparation Example 3: Preparation of Insulating Adhesive Composition 1

Put 20 parts by weight of cyclohexanone and 30 parts by weight of methyl isobutyl ketone into a 10-liter container equipped with a stirrer, and put 10 parts by weight of polyurethane-modified resin (CAPU-1, noru paint) and aluminum hydroxide ( OSDH-3, Ohsung Corporation) 30 parts by weight of the product, stirred for 10 minutes, 10 parts by weight of a dispersant (BYK-167, Bayer), and stirred for 30 minutes to make a mixed solution, and then a basket mill with zirconia beads (Zirconia bead particle size 5㎛) (DWS-25, Daewon Stech) was used to disperse for 40 minutes at 1,500 rpm. The dispersion solution 3 was prepared by filtering the dispersed solution with SUS#1000 mesh.

In a container equipped with a stirrer, 20 parts by weight of the prepared dispersion 3 and 30 parts by weight of a polyurethane-modified resin (CAPU-1, norupate) were added, and 14.5 parts by weight of cyclohexanone and methyl isobutyl ketone. ) 20 parts by weight and stirred for 20 minutes, 15 parts by weight of epoxy-modified resin (YDCN-500-8P, Kukdo Chemical) and 0.5 parts by weight of a leveling agent (BYK 307, Bayer) were added and stirred for 90 minutes. The completely mixed solution was filtered with SUS#1000 mesh to prepare an insulating adhesive composition 1.

Preparation Example 4: Preparation of adhesive composition

12 parts by weight of an epoxy-modified resin (YDCN-500-8P, Kukdo Chemical) was placed in a 10-liter container equipped with a stirrer, and 27.9 parts by weight of cyclohexanone and 20 parts by weight of butyl acetate were added, followed by stirring for 40 minutes. In the dissolved solution, 40 parts by weight of a polyester modified resin (IT-180, norupate) and 0.1 parts by weight of a leveling agent (Dynol 604, Air Products) were added and stirred for 30 minutes to filter the completely mixed solution with SUS#1000 mesh to form an adhesive layer composition. Was prepared.

Example 1

Insulation composition 1 was applied to a carrier film (Thickness 23㎛, PET film) by a slot die coating method and dried for 5 minutes at 170℃ in a drying furnace to prepare an insulating layer having a thickness of 5㎛, and the oven temperature was 100℃. It was aged for 48 hours (Aging). After coating the adhesive composition on the aged insulating layer coating film by a micro gravure coating method and drying it at 150℃ for 3 minutes to form a 5㎛ dry-thick B-stage adhesive layer, release protective film (PS 010 (50), A&S) was laminated and aged in an oven at a temperature of 40° C. for 72 hours to prepare Example 1.

Example 2

Insulation composition 1 was coated on a carrier film (Thickness 50㎛, PET film) by a slot die coating method and dried for 5 minutes at 170℃ in a drying furnace to prepare an insulating layer with a thickness of 7.5㎛, and the oven temperature was 100℃. It was aged for 72 hours (Aging). After coating the adhesive composition on the aged insulating layer coating film by a micro gravure coating method and drying it at 150℃ for 3 minutes to form a 5㎛ dry-thick B-stage adhesive layer, release protective film (PS 010 (50), A&S) was laminated and aged in an oven at 40° C. for 72 hours to prepare Example 2.

Example 3

Insulation composition 2 was applied to a carrier film (Thickness 50㎛, PET film) by a slot die coating method and dried for 5 minutes at 170℃ in a drying furnace to prepare an insulating layer having a thickness of 5㎛, and then the oven temperature was 100℃. It was aged for 48 hours (Aging). After coating the adhesive composition on the aged insulating layer coating film by a micro gravure coating method and drying it at 150℃ for 3 minutes to form a 5㎛ dry-thick B-stage adhesive layer, release protective film (PS 010 (50), A&S) was laminated and aged in an oven at 40° C. for 72 hours to prepare Example 3.

Example 4

Insulation composition 2 was applied to a carrier film (Thickness 125㎛, PET film) by a slot die coating method and dried for 5 minutes at 170℃ in a drying furnace to prepare an insulating layer with a thickness of 7.5㎛, and the oven temperature was 100℃. It was aged for 72 hours (Aging). Apply the adhesive composition to the release protective film (PS 010 (50), A&S) by a micro gravure coating method, and dry it at 150° C. for 3 minutes to achieve a 5 μm semi-cured (B-stage) state. An adhesive layer was prepared. Example 4 was prepared by laminating the prepared insulating layer with the coated carrier film and aging in an oven at 40° C. for 72 hours.

Example 5

Apply insulating adhesive composition 1 to a carrier film (Thickness 50㎛, PET film) by a slot die coating method, and dry it at 140℃ for 2 minutes by drying to form an insulating adhesive layer with a thickness of 20㎛, and then a release protective film (PS 010(50), A&S) was laminated. Example 5 was prepared by aging the prepared thin film coated insulating adhesive film in an oven at 40°C for 72 hours.

Example 6

Insulating adhesive composition 1 is coated on a carrier film (Thickness 50㎛, PET film) by a slot die coating method and dried at a temperature of 140℃ for 2 minutes to form an insulating adhesive layer having a thickness of 30㎛. (PS 010(50), A&S) was laminated. Example 6 was prepared by aging the prepared thin film coated insulating adhesive film in an oven at 40°C for 72 hours.

Comparative Example 1

Heat-resistant and flexible epoxy-based insulation paste (NPR-5/BR-HE No.1, Nippon Polytech Corp.) on a test coupon (flexible printed circuit) was screen-printed using a 180 mesh polyester plate and cured in an oven at 150°C for 30 minutes to test. It was manufactured by forming an insulating layer having a thickness of 10 μm on the printed circuit of the coupon.

Comparative Example 2

Heat-resistant and flexible epoxy-based insulation paste (NPR-5/BR-HE No.1, Nippon Polytech Corp.) on a test coupon (flexible printed circuit) was screen-printed using a 180 mesh polyester plate and cured in an oven at 150°C for 30 minutes to test. It was manufactured by forming an insulating layer having a thickness of 20 μm on the printed circuit of the coupon.

Comparative Example 3

Heat-resistant and flexible epoxy-based insulation paste (NPR-5/BR-HE No.1, Nippon Polytech Corp.) on a test coupon (flexible printed circuit) was screen-printed using a 180 mesh polyester plate and cured in an oven at 150°C for 30 minutes to test. It was manufactured by forming an insulating layer having a thickness of 30 μm on the printed circuit of the coupon.

Comparative Example 4

Heat-resistant and flexible polyester-based insulating paste (CR-18Y2-MS, Asahi Chemical) is screen printed on a test coupon (flexible printed circuit) using a 180 mesh polyester plate, and cured in an oven at 150°C for 30 minutes, and the thickness is applied to the printed circuit of the test coupon. It was prepared by forming an insulating layer of 20㎛.

Comparative Example 5

Heat-resistant and flexible polyester-based insulating paste (CR-18Y2-MS, Asahi Chemical) is screen printed on a test coupon (flexible printed circuit) using a 180 mesh polyester plate, and cured in an oven at 150°C for 30 minutes, and the thickness is applied to the printed circuit of the test coupon. It was prepared by forming an insulating layer of 30㎛.

Comparative Example 6

Put a coverlay (7Q18, Toray) on the circuit wiring of the test coupon (flexible printed circuit), then temporarily bond it with a temporary folding machine (joining condition: 10sec. at 150℃, 3㎏/㎠), and heat bonding with a hot press (press condition). : 60min.at 150°C, pressure 30kg/cm2).

In order to compare and evaluate Examples 1 to 6 and Comparative Examples 1 to 6, samples were prepared by the following method.

After removing the release protective film laminated to the adhesive layer of the thin-film coated insulating film (Examples 1 to 6) prepared above, place it on the circuit wiring part of the test coupon (flexible printed circuit) and attach it with a temporary folding machine (joining condition: 10 seconds, 150° C., 3kg/cm ² ) and then the carrier film was removed. The thin film coated insulating film adjoined to the flexible printed circuit was completely cured and bonded by hot press (press condition: 60 minutes, 150°C, 30kg/cm ^{2) to prepare a sample for evaluation.}

Tables 1 and 2 show the stacked structures and thicknesses of Examples 1 to 6 and Comparative Examples 1 to 6, and cross-sectional structures for sample preparation for evaluation.

Example laminated structure, thickness and evaluation sample Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Carrier film thickness PET film
23μm PET film
50μm PET film
50μm PET film
125μm PET film
50μm PET film
125μm Insulation layer thickness Insulation Composition 1
5μm Insulation Composition 1
7.5μm Insulation composition 2
5μm Insulation composition 2
7.5μm Insulating adhesive composition 1
20μm Insulating adhesive composition 1
30μm Adhesive layer thickness 5μm 5μm 5μm 5μm none none Manufacturing method Lamination Lamination Lamination Paper Lamination Lamination Product form Coating film Coating film Coating film Coating film Coating film Coating film Evaluation sample

Laminated structure, thickness and evaluation sample of Comparative Example Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Carrier film thickness none none none none none none Insulation layer thickness NPR-5/BR-HE No.1
10μm NPR-5/BR-HE No.1
20μm NPR-5/BR-HE No.1
30μm CR-18Y2-MS
20μm CR-18Y2-MS
30μm PI Film
(7Q18)
7.5μm Adhesive layer thickness none none none none none 5μm Product form Paste Paste Paste Paste Paste PI Film Evaluation sample

DSflex-600S (Doosan Electronics) was used for the Flexible Cooper Clad Laminate (FCCL) (DSflex-600S Spec.: PI thickness: 20㎛, Copper foil thickness: 12㎛ (electrolytic copper foil), Pattern: 70㎛/ 70㎛, 60lines)

The prepared sample was evaluated according to the following evaluation method.

Experimental Example 1: Solder heat resistance

Each of the evaluation samples shown in Tables 1 and 2 was floated on a solder at 290° C. for 60 seconds, heated, and allowed to stand at room temperature for 10 minutes, followed by one additional time in the same manner, and then evaluated. The evaluation method was evaluated by visually observing the presence or absence of discoloration and the occurrence of air bubbles before and after soldering. If there is no change in the evaluation sample, Pass, and if there is change, the changed evaluation item is indicated.

Experimental Example 2: Environmental reliability

Each of the evaluation samples shown in Tables 1 and 2 was left in a chamber at a temperature of 85° C. and a relative humidity of 85%RH for 72 hours, and then the presence or absence of discoloration and lifting was visually observed and evaluated. Pass if there is no discoloration, and record the change item if there is a change (FIG. 5).

Experimental Example 3: Chemical resistance

Isopropyl alcohol of 98% purity, 5% sulfuric acid (H ₂ SO ₄ ) aqueous solution, and 5% sodium hydroxide (NaOH) aqueous solution were prepared. The prepared solution was put in a 500 ml beaker each 300 cc and placed in an ultrasonic cleaner (HSD-D250H, Korea Ultrasound Co., Ltd.). The three solutions were heated, and each of the evaluation samples shown in Tables 1 and 2 were immersed in the solution at a temperature of 50° C., followed by ultrasonic cleaning for 30 minutes. The ultrasonically cleaned evaluation sample was washed with purified water and dried in an oven at 50° C. for 30 minutes to observe and visually evaluate the surface change (FIG. 6).

Experimental Example 4: Step Crack

FR4 rods of 0.1t (100㎛), 0.2t (200㎛), 0.3t (300㎛), and 0.4t (400㎛) to be used as a step were cut into sizes of 5mm in width and 25cm in length. The cut FRP rods were arranged at intervals of 20 mm on Cu1.0Oz in the order of thickness, and both ends were fixed with heat-resistant tape. An adhesive layer was placed on the FRP rod in which the thin film coated insulating films of Examples 1 to 6 and the coverlay of Comparative Example 6 were arranged, and heated and pressurized with a heat press (60min. It was fabricated and the FR4 etch portion was observed with a microscope to evaluate the presence or absence of cracks (FIG. 7).

Experimental Example 5: Surface resistance

A surface resistance tester (SRM-110, Wolfgang Warmbier) was placed on the insulating layer surface of each of the evaluation samples shown in Tables 1 and 2, and five locations were measured, and the average of the displayed resistance values was indicated.

Experimental Example 6: Terminal fillability

Each of the evaluation samples shown in Tables 1 and 2 was cut in a section to check the filling properties of the printed circuit board and the coverlay. In the filling evaluation, the cross section was cut to evaluate the degree of filling the insulating layer and the adhesive layer in the space between adjacent circuits. As for the evaluation scale, the area filled in the space of the adjacent wiring was expressed in% (FIG. 8).

Experimental Example 7: Flexibility Evaluation

Solder (60sec. at 260℃) each of the evaluation samples shown in Tables 1 and 2, and then strongly fold the vertical part of the wiring on the copper pattern side 180 degrees with your finger, and then rotate the folded part in the reverse direction. Also, folding was done once. In the same manner, 10 times were performed, and the presence or absence of cracks was observed every 1, 5, and 10 times (FIG. 9).

Experimental Example 8: Elasticity test

Each evaluation sample indicated in Tables 1 and 2 was evaluated with a springback tester (Model: BMSCF-360, BMS Tech), and the values were recorded.

According to the evaluation method according to Experimental Examples 1 to 8, the results of evaluating the prepared Examples 1 to 6 and Comparative Examples 1 to 6 are shown in Table 3.

Example and Comparative Example evaluation results Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Solder heat resistance Pass Pass Pass Pass Pass Pass discoloration discoloration Pass discoloration discoloration Uplifting Environmental reliability Pass Pass Pass Pass Pass Pass discoloration discoloration Pass discoloration Pass Pass Chemical resistance IPA Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass H ₂ SO ₄ Pass Pass Pass Pass Pass Pass Oxidation Oxidation Pass Oxidation Oxidation Pass NaOH Pass Pass Pass Pass Pass Pass Uplifting Uplifting Uplifting Uplifting Uplifting Uplifting Step crack 0.1t Pass Pass Pass Pass Pass Pass N/A N/A N/A N/A N/A Pass 0.2t Pass Pass Pass Pass Pass Pass N/A N/A N/A N/A N/A Pass 0.3t Crack Pass Pass Pass Crack Pass N/A N/A N/A N/A N/A Pass 0.4t Crack Pass Crack Pass Crack Crack N/A N/A N/A N/A N/A Pass Surface resistance (Ω) 10 ¹² 10 ¹² 10 ¹² 10 ¹² 10 ¹² 10 ¹² 10 ³ 10 ⁸ 10 ¹² 10 ⁷ 10 ¹² 10 ¹² Step filling (%) 90% 87% 90% 86% 92% 92% 100% 100% 100% 100% 100% 57% Evaluating the number of bends 10 times pass 10 times pass 10 times pass 10 times pass 10 times pass 10 times pass 5 times
Crack 5 times
Crack 1 time
Crack 5 times
Crack 1 time
Crack 10 times pass Elasticity test (g.f/㎠) 10.1 12.5 10.6 12.8 10.4 12.6 8.5 11.4 16.2 14.5 18.5 20.5

As described above, specific parts of the present invention have been described in detail, and it is obvious that these specific techniques are only preferred embodiments for those of ordinary skill in the art, and the scope of the present invention is not limited thereby. something to do. Accordingly, it will be said that the substantial scope of the present invention is defined by the appended claims and their equivalents.

1: printed circuit metal pattern
2: substrate
11: carrier film
22: insulating layer
33: adhesive layer
44: protective film

Claims (28)

(a) forming an insulating layer on the carrier film; (b) forming an adhesive layer on the insulating layer; And (c) laminating a release protective film on the adhesive layer,
The carrier film is one or more selected from the group consisting of PET film, semi-gloss PET film, matte PET film, PEN film, PES film, TPU film, nylon film, PVC film, synthetic paper, and paper coated with synthetic resin,
The carrier film has a thickness of 20 to 125 μm,
The carrier film has a thermal deformation rate of less than 1% under heat press conditions (60 minutes, 150°C, 30 kg/cm ^{2 ),}
The thickness of the insulating layer is 2 to 12 μm,
The insulating layer is an epoxy resin, polyurethane resin, polyester resin, polyimide resin, amide resin, phenoxy resin, noblock resin, melamine resin, celluloid acetic acid resin, alkyd resin, rosin ester resin, maleic resin, ethylene acrylate At least one resin selected from the group consisting of resins, urethane acrylate resins, epoxy acrylate resins, and modified resins thereof; Aluminum hydroxide; Dispersant; And cyclohexanone or dimethyl acetamide: formed by applying an insulating composition consisting of a coating method,
The insulating layer further comprises a silicone-based surfactant,
The insulating layer further comprises a silane-based coupling agent or a triazine derivative,
The thickness of the adhesive layer is 3 to 30 μm,
The adhesive layer maintains a semi-cured (B-stage) state after coating drying, and is completely cured (C-stage) by heat press after lamination with a printed circuit,
The adhesive layer further comprises an adhesion promoter and a surfactant,
The thin film coated insulating film has a filling rate of 75% or more and an elastic modulus of 15g.f/cm2 or less,
The insulating layer is directly coated on the carrier film,
The adhesive layer is a method of manufacturing an insulating film, characterized in that produced by forming an adhesive layer on a release protective film and laminating it with the insulating layer.
delete delete delete delete The method of claim 1, wherein the insulating layer and the adhesive layer are formed by a single coating using a carrier film.
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