KR101006134B1 - Method of manufacturing flexible laminated plate - Google Patents

Abstract

It is possible to correct the irregularities and wrinkles of the metal foil surface of the flexible laminated board, and to facilitate handling in the post-process of processing it.

The roll surface and metal foil of the plurality of flattening rolls 2 and 3 whose surface is made of metal and whose radius is 100-1500 mm in the laminated board 1 which formed the resin layer from the resin solution on metal foil in 200-450 degreeC atmosphere. Before or after contacting the surface, the compressed gas injectors 6 and 7 are passed through a flattening process, and the warp is removed by the compressed gas injected from the compressed gas injector, and the metal surface and the metal foil of the flattening roll are removed. While the surface is in contact with the range of 2/5 to 4/5 of the length of the roll circumference, and the tension is applied in the flow direction of the laminate, the laminate is brought into contact with the roll in a speed range of 1 to 10 m / min with the roll rotation. The winding method of the obtained elongate flexible laminated board is wound continuously, The manufacturing method of the flexible laminated board characterized by the above-mentioned.

Description

Manufacturing method of flexible laminate {METHOD OF MANUFACTURING FLEXIBLE LAMINATED PLATE}

1 is an explanatory view showing a planarization process of the present invention.

(Explanation of the sign)

1: laminated sheet 2, 3: flattening roll

4, 5: Guide roll 6, 7: Airton

This invention relates to the manufacturing method of the elongate flexible laminated board which consists of metal foil and a resin layer.

The flexible laminate is a laminate of a metal foil and a resin layer. The flexible laminate is used for a part requiring flexibility and flexibility because it has flexibility, contributing to miniaturization and weight reduction of an electronic device. Among the flexible laminates, polyimide is used for the resin layer, and is excellent in heat resistance and dimensional stability, and thus is widely used for wiring boards used in mobile phones and information terminals. As a method of manufacturing a flexible laminated board, the method of bonding a film-like polyimide to metal foil using adhesives, such as an epoxy resin, and the method of directly apply | coating a polyimide resin solution on metal foil, are manufactured, but by the latter It is possible to produce flexible copper-clad laminates having less deterioration due to adhesives and utilizing the properties of polyimide resin. In this way, Japanese Patent No. 3034838 is referred to as a method of manufacturing a flexible laminate.

Examples of failures in the case where a flexible laminate is produced by directly applying a polyimide resin solution to the metal foils exemplified above include curling, generation of ripples, foaming of the resin layer, oxidation deterioration of copper foil, and the like. Among these, since the generation of the corrugation in the flexible laminated plate manufacturing process causes the defect of a product, and lowers a yield, the provision of the manufacturing method of the flexible laminated board without a corrugation was calculated | required.

One of the methods for improving the defect phenomenon and the like, the dimension difference between the metal foil of the flexible metal foil laminate and the layer of the polymer thin film layer including a step of sliding the metal foil in the longitudinal direction in the tension state on the curved surface of the particular bar A method of correcting the problem is disclosed in Japanese Patent Laid-Open No. 64-80530.

(Patent Document 1)

Japanese Patent No. 3034838

(Patent Document 2)

Japanese Patent Application Laid-Open No. 64-80530

According to the method shown by patent document 2, it is shown that curl is correct | amended by correction of an interlayer dimension difference, and handling in a post process is easy. However, the means shown in this patent document aims at correcting the dimensional difference between the metal foil and the polymer thin film layer, and it is practically difficult to correct the wrinkles generated during the manufacture of the flexible laminate.

An object of the present invention is to provide a method for producing a flexible laminate that can correct the wrinkles generated in the flexible laminate manufacturing process.

MEANS TO SOLVE THE PROBLEM In order to solve the said subject, after examining the manufacturing process and the method, after forming the resin layer from the resin solution on metal foil, in the process of conveying this, it uses a roll under a heating atmosphere, and a roll surface And the step of closely adhering the metal foil surface of the laminated sheet made of the metal foil and the resin layer in a state where tension is applied, the inventors found that the correction of the wave wrinkles was possible, and the present invention was completed.

That is, in the manufacturing method of the elongate flexible laminated board which has a metal foil and a resin layer, after making it into the laminated board which formed the resin layer from the resin solution on the metal foil, in the atmosphere of 150-450 degreeC, the surface is metal and a radius The laminated sheet with the roll rotation in such a state that the metal foil surface is in contact with the roll surface of the flattening roll having a thickness of 100 to 1500 mm in the range of 2/5 to 4/5 of the roll circumferential length, and a tension is applied in the flow direction of the laminated sheet. After carrying out the process of carrying out the contact conveyance in the speed range of 1-10 m / min, winding long elongate flexible laminated board is performed continuously, The manufacturing method of the flexible laminated board characterized by the above-mentioned. Here, 1) two to five flattening rolls are disposed, and in each roll, the laminated plate is brought into contact with the above conditions, and 2) a compressed gas injector is arranged before or after the roll surface is brought into contact with the metal foil surface. And providing a step of removing the warpage by the compressed gas injected therefrom, 3) the tension applied to the laminated plate in the range of 100 to 300 N / m, or 4) the metal foil is copper foil, and the resin layer is poly It is a preferable aspect of this invention that it is a mid resin layer.

Hereinafter, the present invention will be described in detail.

Although this invention relates to the manufacturing method of a flexible laminated board, the flexible laminated board manufactured here is a long one. As a unit, it is a thing of width 200-1500mm normally, and becomes 50-3000m. Outline of the manufacturing process of the flexible laminate includes a) preparing a metal foil and a resin solution, b) applying a resin solution to the metal foil, c) drying or curing the resin solution applied to the metal foil to form a laminate, d There is a process of winding the laminated body into a roll, but other processes are added as necessary.

Although the metal foil used by this invention is not restrict | limited in particular about the kind, Preferably, it selects from copper foil or stainless steel foil. In the case of copper foil in this invention, it is defined as containing copper foil alloy. Copper foil alloy means an alloy foil containing copper as essential and containing at least 1 type or more of different types of elements other than copper, such as chromium, zirconium, nickel, silicon, zinc, beryllium, and copper content 90 weight% or more. . The thickness of the metal foil is preferably in the range of 5 to 100 µm, particularly preferably in the range of 12 to 50 µm. If the thickness is less than 5 µm, curling occurs in the laminated sheet in the manufacturing process, and conveyance becomes difficult. If the thickness exceeds 100 µm, sufficient flexibility is not obtained when the laminated sheet is obtained.

As resin, it is preferable that it is heat resistant resin, Specifically, polyimide resin, a liquid crystal resin, etc. are illustrated. The polyimide resin may be one having an imide bond in its structure such as polyimide, polyamideimide and polyetherimide. This resin is used in the form of a resin solution in order to apply it in a uniform thickness. Here, in the case of a resin solution, the state of the precursor resin solution is also included. Although it is preferable to melt | dissolve resin and to have a low boiling point as a solvent used in order to make it into a resin solution, it can also be used as it is, without removing the reaction solvent used at the time of resin synthesis.

As a method of apply | coating a resin solution on metal foil, a well-known means can be used. Specifically, a blade coater method, a knife coater method, a river coater method, etc. can be mentioned.

After the resin solution is applied onto the metal foil in the coating step, it is usually a laminate to form a resin layer on the metal foil by drying or heating to remove the solvent in the resin solution or to promote the polymerization reaction. When the resin precursor solution is applied, it is cured here. The preferable thickness range of the resin layer after drying is 6-80 micrometers, Especially preferably, it is the range of 12-50 micrometers. If the thickness of the resin layer is less than 6 µm, the strength is insufficient for practical use as a laminated plate. On the other hand, if the thickness of the resin layer exceeds 80 µm, flexibility and flexibility are insufficient.

Although the said resin layer may consist only of a single layer, Preferably it consists of multiple layers. When making a resin layer into a polyimide resin layer of multiple layers, it is preferable to use what shows favorable adhesiveness to the resin layer which contact | connects a metal bond. As a polyimide resin which shows favorable adhesiveness, the thing whose glass transition temperature is 350 degrees C or less is mentioned. In addition, in the intermediate layer not in contact with the metal foil, a dimensional change rate with respect to temperature change, i.e., a low thermal expansion resin having a linear expansion coefficient of 30 × 10 ^-6 / ° C or less, in particular 20 × 10 ^-6 / ° C or less, in terms of dimensional stability is used. It is preferable. In the case where the polyimide resin layer is formed of two or more layers, the ratio of the thickness (L) of the low thermal expansion resin layer to the thickness (H) of the high thermal expansion resin layer having a higher linear expansion coefficient than that is H / L = 0.1 to 0.5. It is advantageous to make the range. Here, thickness L and thickness H mean the total thickness, when each resin layer consists of a some resin layer. Moreover, even when a polyimide layer is a multilayer, it is preferable that the linear expansion coefficient as a whole polyimide layer shall be 30x10 <^-6> / degreeC or less.

After the process of drying or hardening and making a laminated body is complete | finished, the process of winding up a laminated body and making it into a roll shape is performed. In the present invention, a flattening step may be provided during the step of forming the roll, and once the laminate is wound (temporarily wound) into a roll, it is unwound again and sent to the flattening step, and after it is flattened, the laminate is rolled up into a roll. You may also The latter method has the advantage that the equipment can be miniaturized, but the former method is advantageous because the former method can be continuously produced, so that the productivity is excellent. Moreover, although the well-known method can be employ | adopted for the winding which does not have a planarization process, a wave wrinkle easily arises in a laminated body, and the defective product rate becomes high. Therefore, in this invention, a flattening process is provided in either the process of winding up a laminated body into a roll shape, or the process of making it into a roll shape after temporary winding.

The process of planarizing the laminated body obtained by heating or drying is provided in the line which conveys a laminated body to a winding roll. This will be described below with reference to the drawings. FIG. 1 is an explanatory view for explaining this planarization step, and the laminate 1 is brought into contact with the metal surface of the planarization rolls 2 and 3 via the guide roll 4 to be planarized to guide the planar roll 5. Via this, it is sent to the take-up roll which omits illustration, and it becomes a roll shape. Although two examples of this roll for knitting are shown in the drawing, at least one of them may be used, preferably a plurality of rolls are used, and two to five are suitable. It is possible to correct wrinkles even with one flattening roll. However, by using a plurality of flattening rolls, the time for adhering the laminate and the flattening roll can be lengthened, so that the wrinkles are more easily corrected.

Although the size of the roll for flattening needs to exist in the range of 100-1500 mm, Preferably it is the range of 150-1000 mm. If the radius is less than 100 mm, the curvature of the roll is large, so that the resin layer and the metal foil cause plastic deformation, and curls are likely to occur on the laminate. Moreover, when the radius exceeds 1500 mm, it becomes difficult to apply the tension required for bringing the laminated sheet into close contact with the roll and correcting wrinkles. The material of the roll is preferably a material having high rigidity such as metal or ceramics and high heat resistance. However, in order to maintain the quality of the metal foil on the laminated plate surface, the roll surface needs to be made of metal. In that case, it is preferable to perform antirust treatment on the surface.

This planarization process is performed under a heating atmosphere. In general, since the glass transition temperature and the heat deformation temperature of the resin used in the resin layer of the flexible laminate are 150 ° C or more, it is difficult to correct wrinkles in the resin layer because only elastic deformation occurs in the temperature range below that. Moreover, since the chemical structure itself of a resin layer changes at the temperature over 450 degreeC, it is unpreferable. Therefore, the atmospheric temperature in a conveyance process needs to be 150-450 degreeC, Preferably it is 200-450 degreeC. In particular, when the resin layer is made of polyimide resin, it is preferable to bring the resin layer into contact with the substrate under a 300 to 400 ° C atmosphere for the above reason.

In the conveyance step, the metal foil surface of the laminate is brought into close contact with the curved surface of the flattening roll inward, but at this time, the laminate is carried out in a state in which tension is applied in the laminate plate flow direction. The tension applied to the laminated sheet is determined by the compressed gas injector disposed as necessary before and after the flattening roll, for example, the pressure of air blown out from the air turns 6 and 7, the rotational speed of the roll, the conveying speed of the laminated sheet, and the like. Can be controlled. It is preferable that the range of the tension applied to a laminated board exists in the range of 100-300 N / m. If this range is less than 100 N / m, it may be difficult to bring the metal foil surface of the laminated sheet into flat contact with the roll. At a pressure exceeding 300 N / m, the laminated sheet is stretched in the flow direction during the conveying process, and the rate of dimensional change is reduced. Anisotropy may arise.

Although the compressed gas injection device, specifically, an air turn, shows the example arrange | positioned in front of the planarization roll 2, and the back of the planarization roll 3, respectively, the position of arrangement | positioning of a planarization roll, a guide roll, etc. is shown. By adjusting, it is not necessary to install. However, when using two or more flattening rolls, it is preferable to provide at least one air turn per 1 flattening roll. In particular, when using two or more flattening rolls, it is preferable to arrange an air turn between the rolls. This airton not only adjusts the tension, but also eliminates warpage to ensure flattening.

Therefore, before or after the metal foil surface and the roll surface of the laminated sheet are brought into close contact, it is preferable to remove the warpage by spraying air or nitrogen with a compressed gas injector. By providing this bending removal process, a metal foil surface and a roll surface become easy to adhere uniformly in the whole part, and the recurrence of the wrinkles after a laminated board is removed from a roll can be prevented.

It is necessary that the range where the metal foil surface and the roll surface of a laminated board are in close contact is 2/5-4/5 of the circumferential length of a roll. That is, when this flattening roll is made into the column shape of radius r, this circumference becomes 2 (pi) r, and it makes it contact in the range of 4/5 (pi) -8-8 (pi) r. If this adhesion range is less than 2/5 of the roll circumference length, wrinkles cannot fully be suppressed. In addition, when the adhesion range exceeds 4/5 of the roll circumferential length, it becomes difficult to make the metal foil surface of the laminate and the adhesion surface of the roll surface uniformly adhere to the whole range, and as a result, the effect of the present invention can be efficiently expressed. There will be no.

The conveyance speed in a conveyance process shall be 1-10 m / min. At speeds of less than 1 m / min, the time the laminate is placed under a heating atmosphere is prolonged, and curling is more likely to occur in the laminate. At speeds exceeding 10 m / min, the time between the metal foil and the roll is shortened to correct wrinkles sufficiently. It is difficult to do.

The metal foil and the flexible laminate are continuously conveyed to the winding step including the coating step, the drying step, and the flattening step, and the tension is continuously applied to prevent the winding shift, the wrinkles, the sagging, and the like from being made of a plastic or paper core. Wound on ash Thus, by carrying out the whole process continuously, a flexible laminated board can be manufactured efficiently. However, after lamination | stacking the laminated board which passed through the drying process, it can also send to a winding process including a planarization process again.

(Example)

Although the Example of this invention is shown to the following and this invention is demonstrated in more detail, this invention is not limited to this.

Example 1

As the resin solution, polyamic acid resin solution A (2500 cp / 24 ° C.) and polyamic acid resin solution B (28000 cp / 24 ° C.) dissolved in N, N-dimethylacetamide were prepared. As the metal foil, a long electrolytic copper foil having a width of 540 mm, a length of 540 mm, and a thickness of 12 µm was prepared. While conveying this copper foil continuously, the resin solution was apply | coated uniformly in three layers so that it might become an order of A, B, and A on copper foil. This coated copper foil was dried for 6 minutes at 90-130 degreeC by the floating furnace, and heat-cured at 130-360 degreeC for 20 minutes, and the copper clad laminated board which has a polyimide thin film layer on copper foil was obtained. It was 40 micrometers when the thickness of the polyimide thin film layer was measured here.

The laminate thus obtained had wavy irregularities (wrinkles) of about 1 to 2 mm in height at a pitch of 10 to 20 mm in the flow direction. Subsequently, in this 270 degreeC atmosphere, this laminated sheet is made into the copper foil surface inside one metal flattening roll curved surface of 300 mm radius, and the said roll surface and copper foil in the state which applied 200 N / m tension in the flow direction of a laminated board. The surfaces were brought into close contact with each other in the range of 7/10 of the circumferential length of the rolls, and the laminate was conveyed at a speed of 5 m / min with the rotation of the flattening rolls. Then, the flexible copper clad laminated board was wound up passing through the roll shape used only for conveyance. The obtained flexible copper clad laminated board had a good appearance without the wrinkles.

Example 2

The laminated sheet produced in the same manner as in Example 1 was subjected to a copper foil surface inside on one flattened metal roll curved surface having a radius of 300 mm in a 220 ° C. atmosphere and to a tension of 220 N / m in the flow direction of the laminated sheet. The roll surface and the copper foil surface were brought into close contact with each other in the range of 1/2 of the circumferential length of the roll, and the laminate was conveyed at a speed of 5 m / min with the rotation of the roll. Then, the flexible copper clad laminated board was wound up through the roll shape used only for conveyance. The obtained flexible copper clad laminated board had a good appearance without the wrinkles.

Example 3

The laminated sheet produced in the same manner as in Example 1 was a copper foil surface on one flattened metal roll curved surface having a radius of 200 mm in a 200 ° C atmosphere, and a tension of 100 N / m was applied in the flow direction of the laminated sheet. The roll surface and the copper foil surface were brought into close contact with each other in the range of 1/2 of the circumferential length of the roll, and the laminated plate was conveyed at a speed of 5 m / min with the rotation of the roll. . Then, the flexible copper clad laminated board was wound up passing through the roll shape used only for conveyance. The obtained flexible copper clad laminate had a good appearance without wavy wrinkles.

Example 4

The laminated sheet produced in the same manner as in Example 1 was subjected to a copper foil surface inward on three continuous flattened metal roll surfaces having a radius of 300 mm in a 360 ° C. atmosphere and to a tension of 130 N / m in the flow direction of the laminated sheet. The roll surface and the copper foil surface were brought into close contact with each other in the range of 1/2 of the circumferential length of the roll, and the laminate was conveyed at a speed of 1 m / min with the rotation of the roll. lost. Then, the flexible copper clad laminated board was wound up passing through the roll shape used only for conveyance. The obtained flexible copper clad laminated board had a good appearance without the wrinkles.

Comparative Examples 1-2

In Example 1, the same operation was performed except having made the contact | adherence range of the roll surface and copper foil surface into the range of 1/5 of the roll circumference length. In this case, the laminated plate and the roll did not adhere uniformly to the conveyance step, and the wrinkles remained on the laminated plate even after the conveyance on the roll was completed.

In Example 1, the operation was carried out under the same conditions under normal temperature atmosphere. In this case, in the conveyance process, the laminated board and the roll were in close contact with each other, but the wrinkles were regenerated after being conveyed on the roll. The state of wrinkles after conveyance was hardly changed from before conveyance.

Comparative Examples 3 to 4

In Example 2 and Example 4, the same operation was performed except having performed in normal temperature atmosphere. In this case, in a conveyance process, a laminated board and a roll did not adhere uniformly. Moreover, the state of the wrinkles after completion | finish of roll conveyance was about the same as before conveyance.

According to the manufacturing method of the flexible laminated board of this invention, the unevenness | corrugation and the wrinkle of the metal foil surface of a laminated board can be correct | amended. As a result, a smooth laminated plate can be obtained, and handling in a later step can be facilitated, and variation in the dimensional change of the resin layer generated when etching the metal foil of the laminated plate can be minimized to an industrial level. High value for use

Claims (5)

In the manufacturing method of the elongate flexible laminated board which has a metal foil and a resin layer, after making it into the laminated board which formed the resin layer from the resin solution on the metal foil, in 150-450 degreeC atmosphere, the surface is metal and a radius is 100-1500 mm. The metal sheet surface is in contact with the roll surface of the flattening roll in the range of 2/5 to 4/5 of the roll circumferential length, and in addition to the tension in the flow direction of the laminated sheet, the laminate is rolled in a range of 1 to 10 m / with roll rotation. A process for producing a flexible laminate, characterized in that the winding of the elongate flexible laminate is continuously carried out after the step of carrying the contact in the speed range of min. The manufacturing method of the flexible laminated board of Claim 1 which arrange | positions 2-5 rolls for planarization, and carries out contact conveyance of a laminated board in each roll. The flexible laminate according to claim 1 or 2, wherein a compressed gas injector is arranged before or after the roll surface is brought into contact with the metal foil surface, and a step of removing wrinkles by the compressed gas injected therefrom is provided. Manufacturing method. The method for producing a flexible laminate according to claim 1 or 2, wherein the tension applied to the laminate is in the range of 100 to 300 N / m. The manufacturing method of the flexible laminated board of Claim 1 or 2 whose metal foil is copper foil, and a resin layer is a polyimide resin layer.

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