WO2011093427A1

WO2011093427A1 - Method for manufacturing a laminate with one metal-plated side

Info

Publication number: WO2011093427A1
Application number: PCT/JP2011/051706
Authority: WO
Inventors: 昭平荒井; 有起岡▲崎▼
Original assignee: 新日鐵化学株式会社
Priority date: 2010-01-29
Filing date: 2011-01-28
Publication date: 2011-08-04
Also published as: TWI508852B; CN102781661A; JPWO2011093427A1; CN102781661B; KR20120124449A; TW201202022A; JP5661051B2

Abstract

Provided is a high-productivity method for industrial manufacture of a laminate with one metal-plated side. Said method results in excellent interlayer adhesion between an insulating film and a metal foil, with no variations in adhesive strength. The provided method also inhibits the formation of aesthetic defects such as wrinkles. The provided method, which manufactures a laminate in which a metal foil (B) is bonded to an insulating film (A) that has an adhesive surface comprising a thermoplastic resin, uses a divider film (C), both sides of which have a surface roughness (Rz) of at most 2.0 μm. Insulating films (A), metal foils (B), and the divider film (C) are layered between a pair of pressure rollers (r₁ and r₂) in the order r₁, B, A, C, A, B, r₂ and bonded via thermocompression bonding. Two laminates, each with one metal-plated side, can then be separated from the divider film (C).

Description

Method for producing single-sided metal-clad laminate

The present invention relates to a method for producing a single-sided metal-clad laminate in which a metal foil is bonded to an insulating film having an adhesive surface made of a thermoplastic resin.

With the recent reduction in size, weight and functionality of electrical devices, the use of flexible circuit boards has increased. For example, metal foil is applied to insulating films such as polyimide films and liquid crystal polymer films whose surfaces are thermoplastic. A crimped metal-clad laminate is preferably used. As a method for producing a laminate having such a structure, a method in which an insulating film and a metal foil are transported by a roll-to-roll method and is continuously thermocompressed through a pair of pressure rolls while being heated is generally employed. Yes.

For example, in Patent Document 1, when a metal foil is thermocompression bonded to one side of an adhesive sheet having a thermoplastic resin layer on both sides of a heat resistant film, a protective material is provided between the pressure surface of the thermocompression bonding apparatus and the adhesive sheet. There has been proposed a method for preventing the thermoplastic resin layer on the side where the metal foil is not laminated from being fused to a metal roll or a protective film. However, in this method, the pressure buffering effect for uniformly applying pressure is poor, and particularly when a thin adhesive sheet or a thin metal foil is used, an unadhered portion or a portion with low adhesive strength is generated due to pressure variation. In addition to this, there is a problem that voids are formed between the adhesive sheet and the metal foil, resulting in appearance defects such as wrinkles.

Further, in Patent Document 2, when a liquid crystal polymer film and a metal foil are overlapped and thermocompression bonded with a metal pressure roll, a heat resistant resin film is further overlapped and laminated on the side in contact with the metal pressure roll. A method of manufacturing a body has been proposed. According to this method, since a heat-resistant resin film is interposed between the laminate for production and the roll, a certain buffering effect can be expected, but conversely, the heat of the pressure roll is transmitted to the laminate. The thermal effect is hindered, and there is a possibility that the adhesive force between the metal foil and the liquid crystal polymer film is lowered or the adhesive force varies.

Further, in Patent Document 3, in a method for producing a laminate in which a thermoplastic polymer film and an adherend are pressure-bonded while being heat-treated between rolls, the thermoplastic polymer film and the adherend are overlapped, and from both sides thereof. There has been proposed a method in which a film and an adherend are firmly bonded in a short time by pressing in a state of being sandwiched between covering materials. However, this method has drawbacks such that the protective material is in direct contact with the heating and pressing surface, so that the protective material is rapidly deteriorated, and the number of reuses of the protective material is reduced, resulting in an increase in manufacturing cost. Similarly to the case of Patent Document 1, when a thin thermoplastic polymer film or a thin adherend is used, there is a risk of formation of an unbonded portion or a weakly bonded portion, and interlayer voids or wrinkles are generated. There is also a fear.

JP 2008-272958 A WO 2004/108397 JP 2001-88219 A

The present invention is excellent in interlaminar adhesion between an insulating film and a metal foil, has no variation in adhesive strength, and suppresses the occurrence of appearance defects such as wrinkles, while producing a single-sided metal-clad laminate with good industrial productivity. It is an object to provide a method that can be manufactured.

As a result of intensive studies to solve the above-described problems of the prior art, the present inventors have determined that the combination of the insulating film and the metal foil is symmetric about the distance film so as to be symmetrical up and down. By stacking and thermocompression bonding with pressure rolls, there is no risk of film fusing to the pressure rolls, and the pressure between the pressure rolls is more evenly transmitted. In addition, it is possible to prevent the occurrence of wrinkles and the like, and further, it is found that two sets of single-sided metal-clad laminates with stable quality can be obtained at a time by peeling off from the separation film, and the present invention is completed. did.

That is, the gist of the present invention is as follows.
(1) A method for producing a single-sided metal-clad laminate in which a metal foil (B) is bonded to an insulating film (A) having an adhesive surface made of a thermoplastic resin,
Using a separation film (C) whose surface roughness (Rz) is 2.0 μm or less on both front and back surfaces, between the pair of pressure rolls (r ₁ , r ₂ ), (r ₁ ) / (B) / ( The insulating film (A), the metal foil (B), and the separation film (C) are stacked and thermocompression bonded so that they are in the order of A) / (C) / (A) / (B) / (r ₂ ). And separating from the separating film (C) to obtain two single-sided metal-clad laminates.
(2) Production of single-sided metal-clad laminate according to (1), wherein the insulating film (A) comprises a thermoplastic liquid crystal polymer film or a heat-resistant resin film having a thermoplastic resin layer on at least one surface. Method.
(3) The single-sided metal-clad laminate according to (1) or (2), wherein the separation film (C) is made of an aluminum foil, a heat-resistant resin film, or a composite film having a metal foil on the front and back surfaces of the resin film. Production method.
(4) The method for producing a single-sided metal-clad laminate according to any one of (1) to (3), wherein one side or both sides of the separation film (C) is subjected to a release treatment.
(5) The method for producing a single-sided metal-clad laminate according to any one of (1) to (4), wherein the metal foil (B) is a copper foil having a thickness of 1 to 100 μm.
(6) The single-sided metal tension according to any one of (1) to (5), wherein the delamination strength between the insulating film (A) and the separating film (C) after thermocompression bonding is 0.1 kN / m or less A manufacturing method of a layered product.

According to the present invention, a high-quality single-sided metal-clad laminate excellent in interlayer adhesion between an insulating film and a metal foil is produced industrially with high productivity, eliminating wrinkles and variations in adhesive strength. Will be able to. That is, the production method of the present invention can significantly increase the industrial production efficiency and can produce a high-quality single-sided metal-clad laminate at a lower cost than the conventional method. And since the single-sided metal-clad laminate obtained by the present invention is high quality and excellent in reliability, it is suitably used, for example, as a substrate material for circuit boards that require fine pattern formation and multilayer circuit boards. be able to.

FIG. 1 is a schematic side view for explaining an apparatus for producing a single-sided metal-clad laminate according to an embodiment of the present invention. FIG. 2 is an enlarged schematic view of the vicinity of the pressure roll. FIG. 3 is a schematic plan view illustrating the test piece used for evaluating the adhesion between the insulating film and the metal foil.

Hereinafter, the present invention will be described in detail.
In the present invention, between the pair of pressure rolls (r ₁ , r ₂ ), metal foil (B) / insulating film (A) / separating film (C) / insulating film (A) / metal foil (B) The two single-sided metal-clad laminates in which the metal foil (B) is bonded to the insulating film (A) are manufactured at the same time.

Here, the insulating film (A) used in the present invention has an adhesive surface made of a thermoplastic resin and is particularly capable of bonding the metal foil (B) to the adhesive surface by thermocompression bonding. There are no restrictions: i) In addition to those made of thermoplastic resin film, ii) A thermoplastic resin layer provided on one side of the heat-resistant resin film to form an adhesive surface, iii) Thermoplastic on both sides of the heat-resistant resin film A resin layer is provided, and any of them is used as an adhesive surface of a metal foil. Moreover, what laminated | stacked these 1 type (s) or 2 or more types into multiple layers can also be used.

Among these, as i) insulating film (A) made of a thermoplastic resin film, for example, polyethylene terephthalate resin, polyethylene naphthalate resin, polycarbonate resin, acrylonitrile / styrene copolymer resin, thermoplastic polyimide resin, liquid crystal polymer, etc. Among these, from the viewpoint of processability, electrical characteristics, heat resistance, and the like, a liquid crystal polymer or a thermoplastic polyimide resin is preferably used.

Examples of the liquid crystal polymer include known thermotropic liquid crystal polyesters and thermotropic liquid crystal polyester amides derived from the compounds classified into the following (1) to (4) and derivatives thereof.
(1) Aromatic or aliphatic dihydroxy compounds (2) Aromatic or aliphatic dicarboxylic acids (3) Aromatic hydroxycarboxylic acids (4) Aromatic diamines, aromatic hydroxyamines or aromatic aminocarboxylic acids

Among the liquid crystal polymers obtained from these raw material compounds, aromatic liquid crystal polymers that do not contain an aliphatic chain in the molecule are preferred. As a typical example of such a liquid crystal polymer, a copolymer having a structural unit represented by the following formula obtained using 6-hydroxy-2-naphthoic acid and p-hydroxybenzoic acid as raw materials can be given. Incidentally, m ₂ and n ₂ in the formula is a positive number indicating the presence molar ratio of the respective structural units.

In consideration of heat resistance and workability in thermocompression bonding, the liquid crystal polymer is preferably in the range of 200 to 400 ° C., more preferably in the range of 250 to 350 ° C., and the transition temperature to the optically anisotropic melt phase. It is good to have. The liquid crystal polymer may be blended with, for example, a lubricant, an antioxidant, a filler, and the like, as long as the characteristics are not impaired.

Examples of the method for forming a liquid crystal polymer into a film include a T-die method, a laminate stretching method, and an inflation method. In the inflation method and the laminate stretching method, stress is applied not only in the mechanical axis direction of the film (MD direction) but also in the direction perpendicular to this (TD direction), so the balance of mechanical properties in the MD and TD directions. An excellent film can be obtained. In addition, a commercial item can also be used for a liquid crystal polymer film, for example, Kuraray Co., Ltd. Vecstar (registered trademark), Japan Gore-Tex Co., Ltd. BIAC, STABIAX (both are registered trademarks), etc. can be used. .

The thermoplastic polyimide resin can be formed by imidizing (curing) the precursor polyamic acid, and the polyamic acid reacts with a known diamine and acid anhydride in the presence of a solvent. Can be manufactured.

As a precursor used for a thermoplastic polyimide resin, a precursor having a structural unit represented by the following general formula (1) is preferable. In General Formula (1), Ar ₃ represents a divalent aromatic group represented by Formula (2), Formula (3), or Formula (4), and Ar ₄ represents Formula (5) or Formula (6). R ₂ represents independently a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, and V and W independently represent a single bond or 1 to 15 carbon atoms. A divalent hydrocarbon group, a divalent group selected from O, S, CO, SO ₂ , or CONH, m ₁ independently represents an integer of 0 to 4, and p is a molar ratio of the constituent units. And a value of 0.1 to 1.0.

Examples of the diamine used include 4,4′-diaminodiphenyl ether, 2′-methoxy-4,4′-diaminobenzanilide, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4 -Aminophenoxy) benzene, 2,2'-bis [4- (4-aminophenoxy) phenyl] propane, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4 Examples include '-diaminobiphenyl and 4,4'-diaminobenzanilide. Examples of the acid anhydride include pyromellitic anhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, and 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride. Products, 4,4′-oxydiphthalic anhydride and the like. Each of the diamine and the acid anhydride may be used alone or in combination of two or more. In addition, a polyimide resin is not limited to what is obtained from the said diamine and an acid anhydride.

When a thermoplastic polyimide resin film is used as the insulating film (A), the film can be formed into a film from a polyamic acid which is a precursor of a polyimide resin by a known method such as a tenter method or a casting method. In the tenter method, which is one of the typical methods, a polyamic acid solution is cast on a rotating drum, peeled off from the rotating drum in the form of a polyamic acid gel film, and heated and cured (imidized) in a tenter furnace. This is a method of forming a polyimide film. The casting method is a method in which a polyamide acid solution is applied to an arbitrary supporting substrate, dried, and then heat-treated and cured (imidized) to form a polyimide film. The imidization can be performed, for example, by heating at a temperature condition in the range of 80 to 400 ° C. for a time in the range of 1 to 60 minutes. In addition, a lubricant, an antioxidant, a filler, etc. can be mix | blended with a polyimide resin in the range which does not impair the characteristic, for example.

When using as the insulating film (A), ii) one provided with a thermoplastic resin layer on one side of the heat resistant resin film, or iii) one provided with a thermoplastic resin layer on both sides of the heat resistant resin film, The heat-resistant resin film is not particularly limited as long as its heat deformation temperature is higher than that of the thermoplastic resin layer, but among them, a non-thermoplastic polyimide resin film is preferable. The non-thermoplastic polyimide resin can be produced by reacting a known diamine and an acid anhydride in the presence of a solvent in the same manner as the thermoplastic polyimide. It can be a polyimide resin. As this non-thermoplastic polyimide resin film, for example, Kapton EN, Kapton H, Kapton V (all trade names) manufactured by Toray DuPont Co., Ltd. ), Upilex S (trade name) manufactured by Ube Industries, Ltd., and the like. The non-thermoplastic polyimide resin film preferably has a glass transition temperature of 300 ° C. or higher, and more preferably does not deform at the thermocompression bonding temperature by a roll.

Further, the thermoplastic resin layer provided on one side or both sides of the heat-resistant resin film may be formed from a resin having a glass transition temperature at least below the heating temperature in thermocompression bonding. Although there is no restriction | limiting in particular, For example, a thermoplastic polyimide resin, a thermoplastic liquid crystal polymer, polyetheretherketone, polyethylene naphthalate etc. can be illustrated. In addition, this thermoplastic resin layer may be formed by bonding a thermoplastic resin film to a heat resistant resin film, or may be formed by applying a precursor by a cast method or the like.

The thickness of the insulating film (A) is preferably 5 to 200 μm, more preferably 10 to 100 μm. If the insulating film (A) is too thin, the rigidity is lowered, and problems such as wrinkles and tearing may occur in the manufacturing process of the metal-clad laminate and the processing process of the wiring board using the obtained laminate. On the other hand, if it is too thick, the insulating film lacks flexibility, and roll-to-roll conveyance in the manufacturing process of the metal-clad laminate becomes difficult, and problems such as difficulty in fitting a circuit-processed wiring board into a narrow housing. There is a fear.

The material of the metal foil (B) used in the present invention is not particularly limited, and examples thereof include gold, silver, copper, stainless steel, nickel, and aluminum. Of these, copper foil and stainless steel foil are preferred from the viewpoints of conductivity, ease of handling, price, and the like. Of these, any copper foil produced by a rolling method or an electrolytic method can be used. In addition, for the purpose of improving the adhesive strength with the insulating film, the metal foil is subjected to chemical surface treatment such as acid cleaning, UV treatment and plasma treatment in addition to physical surface treatment such as roughening treatment in advance. Also good.

The thickness of the metal foil (B) is preferably 1 to 100 μm, more preferably 5 to 70 μm, still more preferably 8 to 20 μm. It is desirable to reduce the thickness of the metal foil because it is easy to form a fine pattern in circuit processing. However, if it is too thin, the metal foil tends to wrinkle in the manufacturing process of the metal-clad laminate, and the circuit processing is performed. In the wiring board, the wiring is easily broken, and the reliability as the wiring board may be reduced. On the other hand, when the thickness is too thick, when the circuit is formed by etching the metal foil, the side surface of the circuit is likely to be tapered, which is disadvantageous for fine pattern formation.

Further, the separation film (C) used in the present invention needs to have heat resistance that can withstand the thermocompression bonding temperature, and needs to be easily peelable from the insulating film (A) after thermocompression bonding. From the latter point of view, the front and back surfaces of the spacing film (C) are both those having a surface roughness (Rz) of 2.0 μm or less, preferably 0.5 to 1.5 μm. Since it is easy to ensure surface smoothness as well as heat resistance, a heat resistant resin film such as a non-thermoplastic polyimide film or polyamide film, or a metal foil such as aluminum foil or stainless steel foil is suitable as the separation film (C). Used. Moreover, the composite film which has metal foil on the front and back of the resin film can also be used. When the surface roughness (Rz) of the front and back surfaces of the separating film (C) exceeds 2.0 μm, the interlayer adhesion between the insulating film (A) and the separating film (C) is improved by the anchor effect, and the insulating film Defects in appearance such as folds and wrinkles in the single-sided metal-clad laminate due to an increase in peeling resistance when the single-sided metal-clad laminate consisting of (A) and the metal foil (B) is released from the separation film (C) May occur.

The separation film (C) may be subjected to a release treatment on one side or both sides of the separation film (C) for the purpose of improving the peelability from the insulating film (A) after thermocompression bonding. As a specific method of the release treatment, for example, a method of providing a heat-resistant release resin film such as a silicone resin or a fluorine resin on the separation film (C) can be mentioned.

The thickness of the separating film (C) is preferably 10 to 300 μm, more preferably 20 to 150 μm, still more preferably 30 to 100 μm. If the separation film (C) is too thin, the pressure buffering effect that uniformly disperses the pressure during thermocompression bonding is reduced, and the interlayer adhesion between the insulating film (A) and the metal foil (B) of the finished metal-clad laminate is reduced. Variation may occur. On the other hand, when it is too thick, there is a possibility that the roll-to-roll type conveyance may be hindered or the workability when peeling from the metal-clad laminate after thermocompression bonding may be deteriorated.

As a combination of the insulating film (A), the metal foil (B), and the separation film (C), it is easy to handle and economical in the thermocompression bonding process (material cost, reusability of the separation film, etc.), and one side obtained From the viewpoint of the characteristics (mechanical characteristics, electrical characteristics, thermal characteristics, workability, etc.) of the metal-clad laminate, the insulating film (A) is a liquid crystal polymer film having a thickness of 10 to 100 μm or thermoplastic on at least one surface. A polyimide film having a resin layer is used, a copper foil having a thickness of 5 to 70 μm is used for the metal foil (B), and the surface roughness (Rz) is 2.0 μm or less for both the front and back surfaces of the separation film (C). It is preferable to use an aluminum foil having a thickness of 5 to 70 μm.

A pair of pressure rolls (r ₁ , r ₂ ) was stacked in the order of (r ₁ ) / (B) / (A) / (C) / (A) / (B) / (r ₂ ). In order to thermocompression-bond the insulating film (A), the metal foil (B), and the separation film (C), a known heating and pressing apparatus having a pair of pressing rolls equipped with a heating mechanism can be used. . At that time, for the insulating film (A), the metal foil (B), and the separation film (C), if a long material wound in a roll shape is used in combination with a heating and pressing apparatus, a single-sided metal is used. Continuous production of a stretched laminate is possible. Moreover, there are no particular limitations on the pressure roll temperature and pressure conditions of the pressure roll, but it is necessary that the thermoplastic resin of the insulating film (A) be well bonded to the metal layer (B) by deformation or the like. For this reason, it is preferable to carry out at a temperature slightly lower than the Tg or melting point of the thermoplastic resin. For example, when a liquid crystal polymer film is used for the insulating film (A), a temperature range 5 to 100 ° C. lower than the melting point is preferable, and a temperature range 20 to 80 ° C. lower than the melting point is more preferable. In addition, the pressurizing pressure is preferably in the range of 20 to 200 kN / m.

In the present invention, the insulating film (A) and the metal foil (B) disposed on both sides of the spacing film (C) are symmetrical with respect to the spacing film (C). Therefore, thermocompression bonding can be performed with the temperature of the pair of pressure rolls (r ₁ , r ₂ ) being the same, and unnecessary heat loss between the rolls can be prevented. Moreover, since all of the pressure rolls are in contact with the metal foil (B), the heat conduction from the pressure roll is not easily inhibited. And after thermocompression bonding, as will be described in the following examples, the delamination strength between the insulating film (A) and the separation film (C) is 0.1 kN / m or less and can be peeled off very easily. It is possible to eliminate variations in adhesive strength, prevent wrinkling, and obtain a high-quality single-sided metal-clad laminate with high productivity. In the present invention, a single-sided metal-clad laminate is obtained from two sets of insulating films (A) and metal foil (B) via a spacing film (C). Thus, it is possible to consider a modification in which two sets of (B) / (A) / (B) are used to obtain two double-sided metal-clad laminates having metal foils on both sides at once.

Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these contents. In the examples of the present invention to be described later, unless otherwise specified, processing conditions and measurement (evaluation) conditions are as follows.

[Measurement of surface roughness]
In accordance with JIS B 0601, using a stylus type surface roughness measuring instrument (manufactured by TENCOR, TENCOR P-10) under conditions of a load of 100 μN, a scanning speed of 20 μm / second, and a measurement distance of 800 μm (10-point average) (Roughness) was measured.

[Evaluation of peelability of separation film (C)]
A laminate (B / A / C / A / B) containing a separation film (C) after thermocompression bonding is cut into a length of 10 mm in the length direction of the pressure roll and a length of 150 mm in the laminating direction (MD direction). A strip-shaped peelable test piece was prepared, and the interlayer peelability between the insulating film (A) and the separating film (C) was measured according to JIS K 6854-3 (T-type peeling). The peeling speed at this time was 100 mm / min.

[Adhesion evaluation of metal-clad laminates]
The obtained single-sided copper clad laminate was cut into a length of 150 mm in the laminating direction (MD direction), and the copper foil was etched by a subtractive method using a commercially available etchant (Adeka Kermica FE-210, manufactured by ADEKA Corporation). Then, a linear conductor pattern 7 having a width of 1 mm and a length of 100 mm was formed along the laminating direction (FIG. 3). At this time, the linear conductor pattern 7 is formed at three positions in the center position in the width direction (length direction of the pressure roll) of the single-sided metal-clad laminate, and 30 mm away from the center in the width direction left and right respectively. An adhesion test piece was obtained. About the three linear conductor patterns of this adhesion test piece, the intensity | strength which peels from an insulating film (A) was measured according to JISC6471 8.1 method B (180 degree direction peeling). And the case where the average value of the three peel strengths is 1.0 kN / m or more is good, the case where it is 0.5 kN / m or more and less than 1.0 kN / m is acceptable, and the case where it is less than 0.5 kN / m “Adhesion” was evaluated in three stages to be defective. Further, the difference between the maximum value and the minimum value among the three peel strengths was evaluated as “adhesion variation”.

Example 1
As the insulating film (A), a long film in which a liquid crystal polymer film 1 (melting point: 320 ° C.) having a thickness of 50 μm and a width of 70 mm is wound is prepared, and a metal foil (B) having a thickness of 12 μm and a width is prepared. A long copper foil in which 70 mm of commercially available electrolytic copper foil 2 (surface roughness Rz: insulating film laminated surface 1.6 μm, exposed surface 1.4 μm) is wound in a roll shape is prepared as a separation film (C) A long aluminum foil in which an aluminum foil 3 having a thickness of 50 μm and a width of 70 mm (surface roughness Rz: 1.2 μm on both sides) was wound in a roll shape was prepared. As shown in FIG. 1, these are set on an insulating film feeding roll A, a metal foil feeding roll B, and a separation film feeding roll C, respectively, and between the pair of pressure rolls 4 (r ₁ , r ₂ ), “ Electrolytic copper foil 2 / Liquid crystal polymer film 1 / Aluminum foil 3 / Liquid crystal polymer film 1 / Electrolytic copper foil 2 ”are supplied so as to overlap in this order (FIG. 2), and naturally cooled after thermocompression bonding. The foil 3 and the liquid crystal polymer film 1 are delaminated, the aluminum foil 3 is recovered by a separation film winding roll C ′, and the single-sided copper clad laminate 5 in which the liquid crystal polymer film 1 and the electrolytic copper foil 2 are bonded together is: It was made to collect with the product winding roll x installed in two places, respectively.

Then, the electrolytic copper foil 2, the liquid crystal polymer film 1, and the aluminum foil 3 are all moved at a speed of 0.7 m / min, and the pressure between the two rolls is between the pressure rolls 4 having a surface temperature of 240 ° C. After thermocompression bonding, the laminate is cooled by natural cooling after thermocompression bonding, and the aluminum foil 3 is collected by the separation film winding roll C ′. The single-sided copper clad laminate 5 according to the above was recovered. Note that the pressure roll 4 of the apparatus used in Example 1 is a carbon steel metal roll having a length of 130 mm and a roll diameter of 150 mm.

In Example 1 above, delamination between the liquid crystal polymer film 1 and the aluminum foil 3 after thermocompression bonding was carried out very smoothly without problems, and the recovered liquid crystal polymer film surface and the electrolytic copper foil surface of the single-sided copper clad laminate 5 were When visually confirmed, no tears, wrinkles, or surface roughness were observed. During the production of the single-sided copper clad laminate 5 according to Example 1, the peelable test piece described above was cut out before entering the peeling roll 6 after being thermocompression bonded with the pressure roll 4, and the liquid crystal polymer film 1 and the aluminum foil 3. As a result of examining the delamination property, it was confirmed that it was an interfacial delamination level at which the numerical value was not measured and it was possible to exfoliate very well. Moreover, from one side of the single-sided copper clad laminate 5 collected at two locations, an adhesion test piece was prepared as described above, and the adhesion evaluation between the liquid crystal polymer film 1 and the electrolytic copper foil 2 was performed. The “adhesion” evaluated by the average value of the peel strengths obtained with the three linear conductor patterns was good. Furthermore, the “variation in adhesion” obtained from the difference between the maximum value and the minimum value among the three peel strengths is 0.03 kN / m, and the liquid crystal polymer film 1 and the electrolytic copper foil 2 are surfaces. It was confirmed that they were evenly bonded inside. The results are shown in Table 1.

(Example 2)
As the spacing film (C), a commercially available heat-resistant polyimide film 3 (Tg: 340 ° C., surface roughness Rz: 0.9 μm on both front and back surfaces) that is non-thermoplastic with a thickness of 50 μm was used. Thus, a single-sided copper-clad laminate according to Example 2 was obtained.

In Example 2, delamination between the liquid crystal polymer film 1 and the heat-resistant polyimide film 3 after thermocompression bonding was performed very smoothly without any defects, and the front and back surfaces of the collected single-sided copper-clad laminate 5 were visually confirmed. However, no tears, wrinkles, or rough surfaces were observed. In the measurement using the peelable test piece, 0.07 kN / m interfacial peeling was confirmed. Furthermore, evaluation by the adhesion test piece shows that “adhesion” is good, “adhesion variation” is 0.02 kN / m, and the liquid crystal polymer film 1 and the electrolytic copper foil 2 are in-plane. It was confirmed that it was adhered evenly. The results are shown in Table 1.

(Example 3)
One side according to Example 3 except that a double-sided copper-clad laminate (Espanex M series (MB12-25-12CEG) manufactured by Nippon Steel Chemical Co., Ltd.) was used as the spacing film (C) A copper clad laminate was obtained. This double-sided copper-clad laminate has a polyimide resin with a thickness of 25 μm as an insulating layer at the center, and a copper foil with a thickness of 12 μm is provided on both sides, and the surface roughness (Rz of the exposed surface of the copper foil) ) Is 1.0 μm.

In the manufacture of Example 3, delamination between the liquid crystal polymer film 1 and the heat-resistant polyimide film 3 after thermocompression bonding was performed very smoothly without any defects, and the front and back surfaces of the collected single-sided copper clad laminate 5 were visually observed. As a result of confirmation, no tears, wrinkles, or rough surfaces were observed. Further, in the measurement using the peelability test piece, 0.04 kN / m interface peeling was confirmed, and in the evaluation using the adhesion test piece, “adhesion” was good and “adhesion variation” was 0. It was 03 kN / m, and it was confirmed that the obtained single-sided copper-clad laminate 5 was uniformly bonded in the plane. The results are shown in Table 1.

(Comparative Example 1)
The single-sided copper-clad wire according to Comparative Example 1 is the same as Example 1, except that a composite polyimide film having a thickness of 25 μm and having thermoplastic polyimide on the front and back surfaces is used as the spacing film (C). A laminate was obtained. This composite polyimide film is obtained by providing a thermoplastic polyimide of about 2 μm on both sides of a non-thermoplastic polyimide of about 21 μm, and the surface roughness (Rz) of the front and back surfaces made of thermoplastic polyimide was 2.3 μm. It was.

In Comparative Example 1, the composite polyimide film used as the separation film did not peel off well from the liquid crystal polymer film 1 after thermocompression bonding, and it was 0.50 kN / m in the measurement using the peelable test piece, confirming the cohesive failure. It was. Moreover, when the front and back of the collect | recovered single-sided copper clad laminated body 5 was confirmed visually, the roughness by the cohesive failure was confirmed on the whole surface of the liquid crystal polymer film. On the other hand, in the evaluation with the adhesion test piece, “adhesion” was acceptable, but “adhesion variation” was 0.15 kN / m, which is a single-sided copper clad laminate compared with the results of the examples. The in-plane adhesion was found to be non-uniform. The results are shown in Table 1.

(Comparative Example 2)
A single-sided copper-clad laminate according to Comparative Example 2 was produced in the same manner as in Example 1 except that the separation film (C) was not used. Although it tried to separate, the liquid crystal polymer film 1 used as the insulating film (A) was heat-sealed, and in the measurement of taking a peelable test piece, it was 0.70 kN / m and cohesive failure was confirmed. It was. The obtained single-sided copper-clad laminate was visually observed to be rough due to cohesive failure on the entire surface of the liquid crystal polymer film, and a single-sided copper-clad laminate with a good appearance could not be obtained.

(Comparative Example 3)
One side according to Comparative Example 3 except that the layers were stacked in the order of “electrolytic copper foil 2 / liquid crystal polymer film 1 / aluminum foil 3” between the pair of pressure rolls 4 except for the above. A copper clad laminate was produced.

In Comparative Example 3, only one single-sided copper-clad laminate can be obtained, but delamination between the liquid crystal polymer film 1 and the aluminum foil 3 after thermocompression bonding is performed smoothly, and the recovered single-sided copper-clad laminate 5 No tears, wrinkles, or rough surfaces were observed on the front and back surfaces. Moreover, the interface peeling of 0.01 kN / m was confirmed by the measurement by a peelability test piece, and “adhesion” was acceptable by the evaluation by the adhesion test piece. However, the “variation in adhesion” was 0.17 kN / m, which was found to be inferior to the in-plane adhesion uniformity as compared with the results of the examples.

(Comparative Example 4)
Comparative example, except that the aluminum foil 3 / electrolytic copper foil 2 / liquid crystal polymer film 1 / aluminum foil 3 are stacked in this order between the pair of pressure rolls 4 except for the above. A single-sided copper clad laminate according to No. 4 was produced.

In Comparative Example 4, only one single-sided copper-clad laminate can be obtained as in Comparative Example 3, but delamination between the liquid crystal polymer film 1 and the aluminum foil 3 after thermocompression bonding was smoothly performed and the recovered single-sided No tears, wrinkles or surface roughness was observed on the front and back surfaces of the copper clad laminate 5. Moreover, the interface peeling of 0.01 kN / m was confirmed by the measurement by a peelability test piece, and "adhesion" was favorable by the evaluation by an adhesion test piece. However, “adhesion variation” was 0.07 kN / m, which was found to be inferior to the in-plane adhesion uniformity as compared with the results of the examples.

From the above results, according to the manufacturing method according to the present invention, a high-quality single-sided metal-clad laminate excellent in interlayer adhesion between the insulating film and the metal foil without wrinkles and variations in adhesive strength is obtained. It was found that it can be produced industrially with high productivity. In addition, this invention is not restrict | limited to the said embodiment, A various deformation | transformation is possible.

1: Liquid crystal polymer film (insulating film (A))
2: Electrolytic copper foil (metal foil (B))
3: Aluminum foil (spaced film (C))
4: Pressure roll 5: Single-sided copper-clad laminate 6: Peeling roll 7: Linear conductor pattern

Claims

A method for producing a single-sided metal-clad laminate in which a metal foil (B) is bonded to an insulating film (A) having an adhesive surface made of a thermoplastic resin,
Using a separation film (C) whose surface roughness (Rz) is 2.0 μm or less on both front and back surfaces, between the pair of pressure rolls (r 1 , r 2 ), (r 1 ) / (B) / ( The insulating film (A), the metal foil (B), and the separation film (C) are stacked and thermocompression bonded so that they are in the order of A) / (C) / (A) / (B) / (r 2 ). And separating from the separating film (C) to obtain two single-sided metal-clad laminates.
The method for producing a single-sided metal-clad laminate according to claim 1, wherein the insulating film (A) comprises a thermoplastic liquid crystal polymer film or a heat-resistant resin film provided with a thermoplastic resin layer on at least one surface.
The method for producing a single-sided metal-clad laminate according to claim 1 or 2, wherein the separation film (C) is made of an aluminum foil, a heat-resistant resin film, or a composite film having a metal foil on the front and back surfaces of the resin film.
The method for producing a single-sided metal-clad laminate according to any one of claims 1 to 3, wherein one or both sides of the separation film (C) are subjected to a release treatment.
The method for producing a single-sided metal-clad laminate according to any one of claims 1 to 4, wherein the metal foil (B) is a copper foil having a thickness of 1 to 100 µm.
The method for producing a single-sided metal-clad laminate according to any one of claims 1 to 5, wherein the delamination strength between the insulating film (A) and the separation film (C) after thermocompression bonding is 0.1 kN / m or less. .