JPH03164241A - Preparation of metal foil-laminated continuous length - Google Patents

Abstract

PURPOSE:To obtain high heat resistance and to obtain easily a metal foil double- clad laminated continuous lengths by adhering a metal foil or a heat-resistant film with a resin layer formed on the metal foil or the heat-resistant film. CONSTITUTION:At least one face of a metal foil or a heat-resistant film is coated with a soln. of a resin wherein an org. solvent-soluble polyimide resin and/or polyamideimide resin are main ingredients in an org. solvent and it is dried so as to obtain a volatile content of 1-30wt.% to form a resin layer. A plurality of heat-resistant films are piled up so as to make the resin layers face to face each other or on a metal foil or a resin layer of the heat-resistant film, another metal foil or heat-resistant film is piled up and they are wound in a roll shape. The metal foil laminated body wound in a roll shape is heated at 150-250 deg.C to remove an org. solvent in the resin layer. When the volatile content is less than 1wt.%, the resin layer does not have enough adhesive properties and in the contrary, when the volatile content exceeds 30wt.%, a volatile org. solvent remains in the laminated body or generates air bubbles.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a long metal foil laminate body that can be used, for example, in a flexible wiring board.

[Prior Art] Flexible wiring is a flexible printed circuit board, and has been widely used in recent years in response to demands for specialized electronic circuits and weight reduction.

Here, the flexible wiring board is a general term that includes so-called flexible four-way boards (FPC), flat cables, tape automated bonding (TAB) circuit boards, and the like.

The conventional manufacturing method for wiring boards is to heat a polyimide film such as DuPont's Kabuton and copper foil through an adhesive layer, and then press them together under pressure.The polyimide film is then etched from a copper-clad board. ing.

Another conventional manufacturing method is to cast and apply a heat-resistant resin solution such as a polyamic acid solution, which is a polyimide precursor, onto copper foil, and then dry and harden it to form a copper foil. Manufactured from stretched laminate by etching.

In the case of manufacturing method (2), there are restrictions on the heat resistance of the adhesive used to bond the heat-resistant film and the copper foil, so the original excellent heat resistance of the heat-resistant film can be maintained as is.
There was a problem that it could not be done.

In the case of the manufacturing method (2), the heat-resistant resin film layer is directly formed on the copper foil, so there is no drawback as in the manufacturing method (2).

[Problems to be Solved by the Invention] However, in the h method of (1), a long laminate is produced in which metal foil is laminated on both sides of a heat-resistant resin film layer, which is called double-sided laminate. It was difficult to do so. This means that in order to laminate metal foil directly onto a heat-resistant film,
This is because the film must be heated above its softening point.

Therefore, an object of the present invention is to provide a method for applying a heat-resistant resin solution onto metal foil, which can easily produce a long metal foil laminated body called "Ameji-bari". There is a particular thing.

[A way to solve problems. [Step] The manufacturing method of the present invention includes applying an organic solvent solution of a resin containing an organic solvent-soluble polyimide resin and/or a polyamide-imide resin as a main component to at least one side of the gold foil or the heat-resistant film. with a volatile content of 1~
The resin layer is dried to 301 m% to form a resin brain, and the metal foil or heat-resistant film on which the resin layer is formed are overlapped so that the resin layer faces the ear hole, or , a process in which another metal foil or heat-resistant film is overlaid on a resin layer of metal foil or a heat-resistant film and wound into a roll, and a metal foil laminate wound into a roll is heated at 150°C to 250°C. and a step of heating to remove the organic solvent in the resin layer.

The organic solvent-soluble polyimide resin and/or polyamideimide resin used in the present invention can be produced by conventionally known direct methods (reaction of acid anhydride and amine), acid chloride methods, isocyanate methods, and the like.

Examples of monomers that can be used are shown in the following in the form of acid and amine components, but these isocyanes-1 as amine components and their acid anhydrides and acid chlorides as acid components are also included. Can be used.

As the amine component, p-phenyl diamine, rl1
-phenylenediamine, 4.4'-diaminodiphenyl ether, 4.4'-diaminodiphenylmethane,
4.4'-diaminodiphenylsulfone, 4.4'
-diaminobenzophenone, 2,27-bis(4-aminophenyl)propane, 2,4-tolylenediamine, 2
．． 6-1-lylene diamine, p-xylylene diamine,
Examples include m-xylylene diamine, isophorone, hexamethylene diamine, and the like.

As acid components, terephthalic acid, isophthalic acid, trimellitic acid, 4.4'-biphenyldicarboxylic acid, pyromellitic moromi, 3.3'. 4.4'-benzofonic nontetracarboxylic acid, 3.3',4.4'-biphenylsulfonetetracarboxylic acid, adipic acid, sebacic acid,
Examples include maleic acid, fumaric acid, dimer acid, and stilbene dicarboxylic acid.

Metal foils that can be used in this invention include copper foil,
There are aluminum foils, nickel coated foils, iron foils, etc., and the surfaces of these foils may be treated with other metals (for example, zinc, chromium, nickel, etc.) or oxides. The thickness of the metal foil is usually preferably 1 μm to 100 μm.

In addition, using metal foil that has not been annealed in quality,
It is also one of the preferred embodiments to simultaneously perform annealing in the final heated embankment of this invention.

Examples of heat-resistant films that can be used in the present invention include polyimide, imide resins such as polyamideimide resins, polyamide resins, polyether ketone resins such as polyether ether ketone, polyether sulfone, etc. There are films and sheets made of so-called heat-resistant resins such as sulfone resins, fluororesins such as Volite 1 and lafluoroethylene, and silicone resins such as polysiloxane. The thickness of the heat-resistant film is usually preferably 1 μm to 100 μm.

In this invention, the solvent for dissolving polyimide and/or polyamideimide resin includes dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, ethyl cellosolve, diethylene glycol dimethyl ether, m-cresol, 0-chloro There are phenols, etc. Further, as the diluent, acetone, toluene, xylene, Solvesso, dioxane, tetrahydrofuran, etc. can be used arbitrarily.

In this case, conventionally known methods can be applied to coat metal foil or heat-resistant film with an organic solvent solution of resin, and roll coaters, knife coaters, doctor blade coaters, etc. can be used. Can be done. The thickness of the coating film containing the solvent is preferably 10 μm to 500 μm, more preferably 100 μm to 300 μm. It is also possible to repeat coating and drying for the same number of kV. Further, in this case, changing the type of resin to be applied is also included in the present invention.

The drying operation is one of the important points of this invention, and it is necessary to adjust the volatile content H of the resin layer coated on the metal foil or heat-resistant film to 1 to 30% by weight. . If the volatile content b'ul is less than 1% by weight, the resin layer will not have sufficient adhesion and it will be necessary to heat-bond it.If the volatile content b'ul exceeds 30% by weight, the inside of the laminate will 7L of todo-generating organic solvent remains or bubbles are formed, making it undesirable as a flexible printable paper.

In this invention, the peaks of the resin layer are stacked on top of each other, or before stacking other metal foils or heat-resistant films on top of each other. It is preferable to move the volatile solvent to the surface of the resin layer. For such movement, one preferred embodiment of the present invention is to bring a heating roll or the like into contact with the metal or heat-resistant film side and heat it from the fan side.

In this invention, the metal foil or heat-resistant film formed with a resin layer is stacked on top of each other so that the resin layers face each other, or on top of the resin layer of the metal foil or heat-resistant film. Overlay with other metal foil or heat-resistant film. In this overlapping process, it is preferable that the overlapping metal foils or heat-resistant films are sandwiched between 1.chi..l rolls and overlapped while being heated and pressurized. Of course, it is also possible to simply overlap them and wind them up.

Next, the metal foil laminate is heated in roll form to 150°C to 250°C. During this heating, volatile organic solvents contained in the resin layer are removed. The heating time is related to the width of the rolled metal foil molded body, the amount of solvent remaining in the resin layer, the temperature, etc., but is usually 3 hours to 20 hours.
It must be kept heated for about an hour. During this heating, it is preferable to heat in an inert atmosphere such as nitrogen or under reduced pressure.

The thickness of the resin layer after heating is generally preferably 1 μm to 150 μm, more preferably 5 μm to 50 μm.
There is no particular limitation as long as metal foil or a film-resistant film is laminated between the resin jφ. For example, if the heat-resistant film is F, the resin layer is R, and the foil is M, the following configurations are included.

F/R/M M/R/F/R/M M/R/M/R/M M/R/M The metal foil dry layer elongated body obtained in this way is processed by conventionally known subtracting techniques, The wiring can be temporarily processed by f-blowing or the like.

In addition, in this invention, other resins, organic compounds, and inorganic υE can be used by combining and/or reacting compounds and the like. For example, resins such as epoxy compounds, silicone compounds, and fluorine compounds, and inorganic compounds such as organic compounds, silicon oxide, titanium oxide, and calcium carbonate may be used within the range that does not impede the purpose of the present invention, i.e. Normally, 1 weight melon% to 30% for the same amount of resin.
It can be used in combination with a weight of 96.

[Operations and Effects of the Invention] In this invention, a heat-resistant resin layer with a high melting point and a high glass transition point is plasticized by containing a small amount of an organic solvent, and is thermally bonded at a temperature below the melting point and the glass transition point. It is. After thermal bonding, the organic solvent remaining in the resin layer is diffused and removed by heating the resin layer for a long time while the resin layer is wound up into a roll.

In the method of this invention, a metal or heat-resistant film is bonded to a metal or heat-resistant film using a resin layer formed on the metal or heat-resistant film. is obtained, and it is also possible to easily cut a so-called double-sided metal foil laminated elongated body.

Therefore, the manufacturing method of the present invention can be widely used as a manufacturing method for flexible wiring boards and the like.

[Example code] It is shown below? 6 all enjoy In%.

Example] A long electrolytic copper foil with a thickness of 35 μm (JT manufactured by Nippon Mining Co., Ltd.
A solution of commercially available polyamide-imide resin (trade name: Torlon 4000T) with a solid content of 20% in N,N-dimethylacetamide (DMAc) was placed on top of the C foil to a thickness of 150.
It was cast and coated using a comma coat so that it became IT+. After coating, the inside of the tunnel furnace set at 80℃ was heated for about 4 hours.
Passed it in minutes. The volatile content of the resin layer at this time was 15%.

A polyimide film (trade name: Kapton 100H) was layered on the resin layer of the laminate (1) thus obtained, and the laminate was laminated by roll lamination at 150°C and 60 kg/cm at 20.5 m/min. (n) was produced. Next, on the film surface of this laminate (n), the laminate (1) prepared in advance was placed so that the resin side faced to each other, and heated at 150°C and 60 kg/am2.
Roll lamination was carried out at 0.5 m/min and the film was wound up.

The obtained roll-shaped body was heated in a hot air dryer heated to 160° C. for 15 hours to obtain a long double-sided flexible printed circuit air plate. This double-sided flexible printed circuit wiring board was evaluated for appearance, adhesive strength, 'I'-ITJ heat resistance, and appearance after etching.

The adhesive strength was determined to be 7 lpj by peeling at 90° at a tensile speed of 50 mm/min. The heat resistance of 1111 was evaluated by floating the sample in a half-river bath at 260° C. and measuring the time it took for the sample to swell and peel. The results are shown in Table 1.

Example 2 (Manufacture of polyamide-imide resin) 19.28 g (0.10 mol) of trimellitic anhydride and 2.4 g of trimellitic anhydride were placed in a 4-separable flask equipped with a thermometer, a stirring device, a reflux condenser, and a nitrogen inlet tube. -Tolylene diisocyanate (2.4-TDI) 3.5 L) g (
0.02 mol), bitolylene diisocyanate (TOD
I) 21.10 g (0.08 mol) of N-methyl-
Add to 150 g of 2-pyrrolidone (NMP) and heat to 160° C. with stirring. The mixture was heated for 1 hour and further reacted at 160°C for 5 hours. N of the obtained polymer
Logarithmic viscosity in MP was 1.81.

(Product) Production of φ body) Add 10% of commercially available epoxy resin (trade name, Epicoat 154) to NMP solution lfk of polyamideimide resin.
6 and added NMP to make a 15% solution.

This solution was cast in the same manner as in Example 1, and then
The mixture was continuously passed through a tunnel furnace set at 0°C. The volatile content of the resin layer at this time was 2,896. The resin layers of the bond layer body thus prepared were stacked facing each other, and then heated at 150°C, 60kg/cm2, and 0.5°C.
It was roll laminated and wound up at 5 m/min.

The obtained roll-shaped product was heated in a hot air dryer heated to 200° C. for 20 hours to obtain a long double-sided flexible printed circuit board. The IP value of this double-sided flexible printed circuit board was determined in the same manner as in Example 1. The results are shown in Table 1.

Length Example 3 A 20% DMAc solution of the commercially available polyamide-imide resin (trade name: Torlon 4000T) used in Length Example 1.
Add 2U of epoxy resin (product name: Epicoat 154) to k.
%, and a laminate was produced in the same manner as in Example 1.

The volatile content D (-r'Gk) of the resin layer at this time was 12%.
H. Layer them so that they are oriented in the χ・I direction, and heat them at 150°C.
Roll lamination was performed at 601 cg/crn2 and 0.5 m/min, and the material was wound up.

The obtained roll-shaped product was heated at 150°C for 15 hours,
A long double-sided flexible printed circuit board was obtained. Evaluation of this double-sided flexible printed substrate for river passage was carried out in the same manner as in Example 1. The results are also shown in Table 1.

Length Example 4 Instead of the commercially available polyamide-imide resin (trade name: Torlon 4000T) used in Length Example 3, N,N-dimethylformamide (DMF) of a commercially available polyimide resin (Up John Chu 2080) was used. A laminate was obtained in the same manner as in Example 1 by blending 1096 epoxy resins (Nishi product name: Epicoat 154) into a solution having a solid content of 20%. The volatile content 6l-TQ of the resin layer at this time was 7%. A polyimide film (trade name: Upilex S) was superimposed on the resin layer of the laminate thus obtained, and
, 601 cg/cm 2 and 0.5 m/min, and the film was rolled up. The obtained roll-shaped product was heated to 160
15 rl. A long, single-sided flexible printed circuit board was heated for a period of 10 minutes. This single-sided flexible printed circuit board was measured in the same manner as in Example 1. The results are also shown in Table 1.

Comparative Example 1 A laminate was produced in the same manner as in Example 2, except that the coating was passed through a tunnel for 2 minutes to dry after coating. The non-volatile content of the resin was 28% in Example 2, while it was 45% in Comparative Example 1. Joshi F! AI
Using this laminate, a long flexible printing circuit board was obtained, which had the same square width as in Example 2. The obtained double-sided flexible printed circuit preliminaries had significant flow of the resin layer and swelling of the copper foil. The s/+r value was carried out in the same manner as in Example 1, and the results are also shown in Table 1.

Comparative Example 2 Example 1 and I, i1 except that the resin layer after coating was dried by passing through a tunnel furnace at 80°C for 4 minutes and then passing through a tunnel at 200°C for 4 minutes. A laminate was produced. The non-volatile content of the resin layer of the right melon in Comparative Example 2 was 0. It was 5%. Using this laminate, a polyimide film (trade name: Kabuton 100H) was overlaid in the same manner as in Example 1, and the film was heated at 200°C for 60k.
When roll lamination was carried out at a speed of 20.5 g/cm/min, a laminate with good adhesion could not be obtained. Length The results were evaluated in the same manner as in Example 1, and the results are also shown in Table 1.

As is clear from Table 1, length examples 1 to 1 according to the present invention
No. 4 has stable and high adhesive strength and good heat resistance. On the other hand, in Comparative Example 1 in which the volatile content in the resin layer exceeds the range of the present invention, blistering of the copper foil and generation of bubbles in the resin layer after the final heat treatment were observed. Discoloration was also observed. The adhesive strength showed highly variable values.

Furthermore, in Comparative 81I2, which had a lower volatile content than the fourth range of the resin composition of the present invention, the adhesive strength was insufficient and almost no bonding could be achieved.

Claims (1)

[Claims] (1) At least one surface of the metal foil or heat-resistant film is coated with an organic solvent solution of a resin whose main component is an organic solvent-soluble polyimide resin and/or a polyamide-imide resin, and the volatile content is 1 to 30%. % by weight, and stacking a plurality of metal foils or heat-resistant films on which the resin layers are formed so that the resin layers face each other, or A process of overlaying another metal foil or heat-resistant film on the resin layer of the metal foil or heat-resistant film and winding it into a roll, and heating the rolled metal foil laminate at 150°C to 250°C.
A method for manufacturing a metal foil laminated elongated body, comprising a step of heating the resin layer to remove an organic solvent in the resin layer.