KR100855420B1 - Accompanying winding spacer and method for manufacturing strip type materials using the same - Google Patents

Abstract

An accompanying winding spacer and a method for manufacturing strip type materials are provided to prevent undesired residues, patterns and wrinkles from being formed on a surface of a laminate material by removing byproducts from the surface of the laminate material. A method for manufacturing strip type materials comprises the steps of preparing a strip laminate including a substrate and a material layer deposited on the substrate, winding the strip laminate and a spacer(20) in the form of a roll by pressing a surface(24) of the spacer against the material layer of the strip laminate, and heat-treating the roll of the strip laminate and the spacer in order to discharge volatile materials from a recess of the spacer. The material layer includes volatile materials. The spacer separates all layers of the strip laminate from each other.

Description

Accompanying winding spacer and method for manufacturing strip type materials using the same}

1 is a schematic view of a conventional accompanying winding spacer, in which (A) is a plan view and (B) is a cross-sectional view along the B-B line of (A).

2 is a schematic diagram of an accompanying winding spacer according to the invention, where (A) is a plan view and (B) is a cross sectional view along the B-B line of (A).

* Description of the Drawing Symbols *

10: Conventional companion winding spacer

12: protrusion

20: companion winding spacer of the present invention

22: support plate

24: smooth first surface

26: second surface

28: rough

FIELD OF THE INVENTION The present invention relates to apparatus and methods for removing volatiles contained in materials, in particular when producing laminates for flexible printed circuit boards (PCBs) such as volatile solvents and / or gases. An apparatus and method for removing by-products.

Conventional methods for removing volatile solvents and gaseous by-products contained in strip laminates have been heat treatment by heat treatment or reduced pressure (eg, vacuum). These methods remove volatile solvents and / or gaseous by-products, dry the material, and effectively accelerate chemical reactions, including polymerization. For example, polyamic acid (PAA) varnishes containing one or more volatile solvents are coated on the surface of copper foil in the manufacture of copper clad laminates for flexible printed circuit boards. . In the next step, that is, the curing stage, the one or more volatile solvents used to dissolve the byproducts, including polyamic acid (PAA) and water, are removed and the polyamic acid is removed by heat or radiation such as ultraviolet or infrared radiation. Polymerized to PI). This curing process may be carried out by a continuous process or a batch type process. In the case of continuous processes, long curing times always lead to long curing drying which leads to expensive equipment and operating costs and serious control and operating difficulties.

In order to solve this problem, Japanese Patent Laid-Open No. 61-307789 discloses a heating method of winding a strip laminate in a roll state and heat treating the strip laminate. The method does not use any of the accompanying winding spacers, resulting in the problem of sticking between the layers of the rolled strip laminate. In order to solve the above fixing problem, Japanese Patent Laid-Open No. 4-84488 discloses a companion winding spacer made of a non-woven fabric or a stainless steel mesh having a surface roughness Ra of greater than 0.5 μm ( Disclosed is a heating method using a accompanying winding spacer. The practical application of the method is not sufficient for problems such as the fixing of nonwoven fibers as well as the transfer of patterns of the surface of the processed material (eg, patterns of fibers and mesh patterns). Another Japanese Patent Application Laid-Open No. 8-224797 discloses a companion winding spacer 10 made of copper foil having a rough surface including a plurality of protrusions 12 on one side and a smooth surface on the other side (FIG. 1). The rough surface of the spacer is pressed against the monomer-coated surface of the strip laminate. The spacer and strip laminates are then wound up in rolls. And when the spacer and strip laminate are heat treated, the volatile solvent is evaporated and released from the gaps between the protrusions 12. This method can prevent the fibers from sticking to the surface of the material being processed and can reduce the pattern transfer at the surface of the processed material. However, the problem of pattern transition still cannot be completely avoided. In addition, the spacers are expensive to produce and retreat of the spacers is frequently because the remaining monomers or by-products just jam the gaps on the rough surface of the spacers.

To completely solve the pattern transfer problem of the common heating method, another heating method discloses a spacer made of a metal mesh strip. The spacers are respectively disposed at two longitudinal edges of the strip laminate, the strip laminate and the spacer are then rolled into rolls, and the strip laminate and spacer are cured together. After the curing process, the two longitudinal edges of the patterned laminate are cut off. Thus, the finished product does not have any pattern. The practical application of this method also has some disadvantages. For example, when the metal mesh strip is rolled together with the strip laminate, unwinding the rolled mesh strip generates friction. The frictional force of the metal mesh strips creates different operation tensions and unwound speeds. Thus, the metal mesh strip exerts different forces on both edges of the strip laminate to corrode the strip laminate. In addition, if the metal mesh strip is too thick, a standing-up roll of the strip laminate does not support the load of the metal mesh strip and buckles. Therefore, the surface of the strip laminate is corrugated to have a damaged appearance. On the other hand, if the metal mesh strip is too thin, the roll strip laminates stick to each other. The metal mesh strip also loses its function, either because hot air cannot pass through the gap on the metal mesh strip or the ratio of ventilation length to gap is too large. It also leads to differences in physical and chemical characteristics in the inner and outer layers of the roll strip laminate. Furthermore, this problem cannot be solved by radiation heat treatment.

In order to solve the problems of the general heating method described above, the present invention provides an apparatus and method using a spacer to release the volatile solvent contained in the material. This method has the disadvantages of the conventional heating methods described above: unwanted residues (fibers, etc.), patterns and wrinkles are present on the surface of the strip laminate material and physical and chemical properties in the inner / outer layers of the roll strip laminate Overcome the disadvantages of changing (eg, non-uniform surface color).

In order to achieve the above object, the spacer according to the invention is used to release the volatiles contained in the strip laminate. The strip laminates and spacers are wound together in rolls and heat treated to release volatiles. The spacer has a surface with a smooth surface on one side and a rough surface protruding on each of the two longitudinal edges. The rough portion comprises a plurality of recess portions as gas passages.

The strip laminate and spacer of the present invention are wound together in a roll. The volatile material is released from the strip laminate when the strip laminate is heat treated via depressions provided in the rough portions of the longitudinal edges of the spacer.

A method for producing a laminate for a printed circuit board using a companion winding spacer according to the present invention comprises the steps of: (1) providing a strip laminate comprising a substrate and a layer of material coated on the substrate and containing a volatile material; ; (2) the spacers separate all layers of the roll strip laminate, and the surface of the spacer having the rough portion is pressed against the material layer of the strip laminate so that the strip laminate and the spacers are rolled and rolled; And (3) heat treating the strip laminate and the roll of spacers to release volatiles from the depressions of the roughness at both edges of the spacer.

The accompanying winding spacer according to the invention effectively prevents the strip laminate from wrinkling due to an unbalanced tension at both edges of the spacer. In addition, the spacer of the present invention can be made of a heat conducting material to increase the heat-dissipative cross-sectional area (ie, the thickness of the strip laminate with the spacer is greater than the thickness with only the strip laminate). Thus, the spacer minimizes the temperature difference between the roll strip laminate inner and outer layers, and prevents the inner and outer layers of the strip laminate from having different physical and chemical properties due to temperature differences. In addition, the spacer according to the invention effectively improves the strength of the roll strip laminate and prevents the standing roll strip laminate from buckling due to the overweight of the spacer located at the upper edge. Therefore, the spacer according to the invention makes it possible to produce extra-thin strip laminates.

The strip material used in the present invention is a thin layer material having a length to width ratio of greater than ten. The strip laminate used in the present invention is a stacked composite consisting of a plurality of said strip materials.

Referring to Figure 2, the accompanying winding spacer 20 of the present invention is used to release the volatiles contained in the strip laminate. The strip laminate and spacers 20 are wound in rolls and heat treated to remove the volatiles. The spacer 20 includes a support plate 22 having a soft first surface 24 and a second surface 26 opposite the first surface 24. The second surface 26 has rough portions 28 protruding at each of its longitudinal edges. The rough portion 28 is an integral or separate portion of the second surface 26 of the spacer 20. When considering cost as well as replaceability, a separate rough portion 28 is preferred.

When the rough portion 28 and the support plate 22 are integral parts of the spacer 20, the rough portion 28 is a structure having continuous convex portions. There is no particular limitation on such structures. The present invention can be used in any general structure in which heated and evaporated volatiles can be released from the edge of the roll strip laminate through the continuous recess portion without blocking the flow of volatile gases.

For example, the structure described above with continuous depressions is a plane that includes a plurality of protrusions. The protrusion includes a cylinder, an elliptical column, a horseshoe column, a rectangular column and a trapezoidal column. The protrusions are manufactured by mechanical or chemical processes such as machining, etching and the like.

When the rough portion 28 and the support plate 22 are separate portions of the spacer 20, the rough portion 28 is a strip structure with continuous depressions such as mesh strips. There is no particular limitation on such structures. The height of the rough portion 28 according to the present invention is not particularly limited as long as the vapor is thick enough to be released through the depressions. However, it is preferable that the said height is between 15-1000 micrometers.

The support plate 22 of the spacer 20 is made of the same or different material as the rough portion 28. In addition, any material excellent in high temperature and exhibiting heat resistance can be applied to the present invention. In view of both the heat conduction and support elements for the roll strip laminate, the support plate 22 is preferably a laminate coated with copper foil, aluminum foil, stainless steel foil or the above-described metal foil. There is no particular limitation on the thickness of the support plate 22 according to the present invention. However, for effective support, the total thickness for the support plate 22 and the strip laminate is preferably between 30 and 3000 μm. Therefore, the present invention is applicable to ultra-thin strip laminates (for example, 9 μm copper film laminates).

The strip laminate using the accompanying winding spacers 20 according to the invention may be a strip laminate having a heat resistant resin film coated on a metal foil. The resin film contains a volatile material, which is released by heat or radiation treatment. The strip laminate according to the invention may be a copper film laminate or an aluminum film laminate coated by a polymer such as polyethylene, polypropylene, polyester, polyamide, polyimide or polystyrene or a combination thereof. However, the strip laminate is not limited to the samples described above.

The soft first surface of the spacer 20 according to the invention is a plane having a substantially smooth surface, although having a small change in the height of the physical surface. The smooth surface 24 has an average roughness depth Rz of less than 1 mm. In addition, the depressions of the roughened portion 28 on the spacer 20 according to the present invention may have different sizes or non-uniform distributions, as long as they do not affect the release of volatiles from the depressions.

The strip laminate comprising the volatile materials mentioned in the present invention comprises a plurality of separate metal foils supported by a layer of material. The material layer may be made of a single material or a plurality of materials. Metal foils, such as copper foils used in the strip laminates, can be coated using polyimide resin precursor solutions as the base substrate.

The accompanying winding spacer 20 according to the invention is used to produce a laminate for the printed circuit board. The laminate for the printed circuit board includes a conductive layer made of a metal foil (eg, copper foil) and an insulating layer which is a resin solution (eg, polyimide resin precursor) coated on the metal foil. Each of the laminates may be pre-dried and then rolled together with a spacer 20 according to the invention in a rolled state. When winding the laminate and the spacer 20, the soft first surface 24 of the spacer 20 faces the conductive layer of the laminate and the second surface 26 toward the insulating layer. Solvents and byproducts remaining in the polyimide resin precursor are evaporated and released when the roll laminate is cured. During the heat treatment, a ring-closing reaction converts the precursor to polyimide. Water (water) and other by-products produced in the reaction and monomers (gas by-products) which remain unreacted are also evaporated and released.

The volatile material heated and evaporated as described above is discharged from the inside of the roll laminate through a passage formed by depressions of the rough portion 28 located at both longitudinal edges of the spacer 20. This prevents the surface of the finished product from being contaminated by preventing volatiles from accumulating between and within the roll laminate layers. The soft first surface 24 of the spacer 20 is in contact with the conductive layer to prevent the appearance of the laminate from becoming tacky. In addition, the spacer 20 reinforces the standing roll laminate by increasing the cross sectional area with respect to the roll laminate. Since the spacer 20 increases the conductive cross sectional area, it also improves thermal conduction efficiency. Therefore, the temperature difference between the inner and outer layers of the roll laminate is minimized. This prevents the inner and outer layers of the laminate from having different physical and chemical properties (eg, uneven surface color) due to the difference in heating temperatures of the inner and outer layers of the roll laminate.

In addition, the soft first surface 24 of the spacer 20 according to the invention is pressed against the conductive layer of the laminate to increase the cross-sectional area of the load-bearing laminate. Although conventional metal mesh strips are used as the roughness 28 of the spacer 20 and the metal mesh strips have different tension and releasing speeds at both longitudinal edges of the spacer 20, the increased cross sectional area is both. Makes the spacer 20 less sensitive to different tensions at the edges. Therefore, there is less possibility of wrinkles on the laminate.

While the present invention has been described in connection with the preferred embodiments, the above-described embodiments are illustrative rather than limiting, and thus the invention is not limited to the above description and various changes and modifications may be made without departing from the scope of the appended claims. It is obvious to those skilled in the art that it is possible.

The present invention can solve the above-mentioned problems of the prior art by releasing volatile substances and by-products contained in the strip laminate by the above configuration.

Claims (12)

As a companion winding spacer for releasing volatiles contained in the strip laminate: A soft first surface provided at one side; And A second surface having a rough portion protruding on each of the longitudinal edges, the second surface being provided on an opposite side of the first surface; A companion winding spacer wound together with the strip laminate in a rolled state and heat or radiated to release volatiles and by-products. The spacer of claim 1, wherein the rough portion and the second surface of the spacer are integral parts. 3. The spacer of claim 2, wherein the rough portion has a structure with continuous depressions. 4. The spacer of claim 3, wherein the rough portion comprises a plurality of protrusions protruding from the second surface. The spacer of claim 1, wherein the roughened portion and the second surface of the spacer are separated parts. 6. The spacer of claim 5, wherein the rough portion is a strip structure with continuous depressions. 7. The spacer of claim 6, wherein said strip structure is one of a metal strip and a metal mesh strip. The spacer of claim 1, wherein a total thickness of the spacer and the strip laminate is 30 to 3000 μm. 2. The method of claim 1, wherein when the spacer and the strip laminate are wound together in a rolled state, the soft first surface of the spacer is pressed against one side of the strip laminate containing no volatile material and having a roughened portion. The second surface is pressed against the other side of the strip laminate containing volatiles. The spacer of claim 1, wherein the height of the rough portion is 15 to 1000 μm. The spacer of claim 1, wherein an average roughness depth Rz of the soft first surface is less than 1 mm. (1) providing a strip laminate comprising a substrate and a layer of material coated on the substrate and containing a volatile material; (2) The spacer separates all layers of the roll strip laminate, and the surface of the spacer having the rough portion is pressed against the layer of the strip laminate containing volatiles and by-products to roll the spacer and strip laminate of claim 1 in a rolled state. Stacking and winding up with; And (3) heat or radiation treatment of the roll of spacer and strip laminate to release the volatiles from the recesses of the rough portions provided at both edges of the spacer; Method for producing a laminate for a printed circuit board.

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