JP5080907B2 - Method for producing double-sided metal foil-clad laminate - Google Patents

Description

  The present invention relates to a method for manufacturing a double-sided metal foil-clad laminate used for manufacturing printed wiring boards and the like.

  Conventionally, a double-sided metal foil-clad laminate in which a metal foil such as a copper foil is provided on both sides of an insulating layer, wherein the metal foils on both sides are electrically connected by bumps penetrating the insulating layer, so-called bump connection A metal foil-clad laminate has been proposed (see, for example, Patent Document 1). Such a double-sided metal foil-clad laminate is manufactured as follows.

  First, a plurality of bumps 1, 1... Are formed on the upper surface of the metal foil 2. The bump 1 can be formed in a shape having a sharp tip (upper end) such as a conical shape by making a semi-cured state after printing a conductive paste or the like. Next, the insulating sheet material 3 is placed (build-up) on the upper surface of the metal foil 2 on which the bumps 1 are formed and overlapped, and the bumps 1 are pierced through the insulating sheet material 3 from below to penetrate the insulating sheet. The tip of the bump 1 is protruded from the upper surface of the material 3. As the insulating sheet material 3, a resin film, a prepreg (resin-impregnated base material), or the like can be used. In this way, the metal foil 2 on which the bumps 1 are formed and the insulating sheet material 3 are overlapped to form an overlap 20, and a plurality of overlaps 20, 20... Are stacked while being manufactured sequentially. Here, a slip sheet 21 is interposed between the stacked products 20 adjacent to each other vertically. The slip sheet 21 is used to protect the bump 1 from damage such as cracks and chips, and to prevent the bump 1 and the insulating sheet material 3 from directly contacting the lower surface of the metal foil 2. Paper for preventing foreign matter such as conductive foreign matter from adhering. In FIG. 3A, a part of the plurality of stacked objects 20, 20,.

  Next, after the plurality of stacked products 20, 20... Are conveyed to the molding process, one superimposed product 20 is removed from the stacked product while removing the interleaf 21 as shown in FIG. Take out. Thereafter, another metal foil 5 is placed (build-up) on the taken-up stack 20. As a result, the other metal foil 5 is placed in contact with the tip of the bump 1 protruding from the upper surface of the insulating sheet material 3. Next, as shown in FIG. 3C, a superposition of the metal foils 2 and 5 and the insulating sheet material 3 is placed between the two upper and lower forming plates 22 and 22, and then heated and pressed. By forming and hardening the insulating sheet material 3, an insulating layer is formed from the insulating sheet material 3, and the metal foils 2 and 5 are bonded and integrated with the insulating layer. In this way, a double-sided metal foil-clad laminate can be formed.

In general, in the manufacturing process of the double-sided metal foil-clad laminate as described above, the ambient atmosphere such as when building up the metal foils 2 and 5 and the insulating sheet material 3 should be performed in a place where the cleanness is as high as possible. Is ideal. However, in the double-sided metal foil-clad laminate produced as described above, molding defects may occur due to dents (dents) on the surface of the metal foil 2 on which the bumps 1 are formed. This dent is caused by foreign matter 6 such as resin powder generated from the insulating sheet material 3. That is, after the foreign matter 6 generated on the surface of the insulating sheet material 3 falls on the lower interleaf paper 21, the lower metal foil 2 is conveyed during transportation to the molding process or handling (work) in the molding process. And the lower interleaving paper 21 are displaced from each other, so that the foreign matter 6 enters between the lower metal foil 2 and the lower interleaving paper 21 and is heated and pressed in this state. The foreign matter 6 is pressed against the surface (lower surface) of the metal foil 2 and a dent is generated. When such dents are generated, not only the appearance defect but also the pattern defect is caused in the subsequent circuit pattern formation.
Japanese Patent No. 3251711

  This invention is made | formed in view of said point, and it aims at providing the manufacturing method of the double-sided metal foil clad laminated board which can reduce generation | occurrence | production of a dent.

Method for producing both sides a metal foil-clad laminate of the present invention, by penetrating pierce the bumps 1 in the insulating sheet 3 causes the metal foil 2 formed with bumps 1 on the upper surface overlapping the insulating sheet 3 the formation of the insulating sheet 3 superposition product 20 is protruded the tip of the bump 1 on the upper surface, a so as to contact the tip of the bump 1 and another metal foil 5 and the insulating sheet 3 overlay, and thereafter, in the manufacturing method of the double-metal-foil-clad laminate to integrate the said insulating sheet member 3 and the metal foil 2, 5 by press molding, the insulating sheet material and said another metal foil 5 3 is overlapped with the interleaving papers 21 and 21 superimposed on the top and bottom of the superposed product 20 and then the interleaving papers 21 and 21 are removed from the superposed material 20. Features It is intended.

The method of manufacturing both sides a metal foil-clad laminate of the present invention, after inverted vertically superposed state interleaves 21 and 21 and below the overlay object 20, the insulating sheet 3 of the metal foil 2 It is preferable to remove the foreign matter 6 adhering to the surface that is not superimposed.

Method for producing both sides a metal foil-clad laminate of the present invention is preferably removed by capturing the previous SL foreign matter 6 in slime 7.

Method for producing both sides a metal foil-clad laminate of the present invention, when the pre-Symbol foreign matter 6 is removed by capturing in the adhesive material 7, it is preferable to 0.1~100kPa the pressure applied to the metal foil 2 .

Method for producing both sides a metal foil-clad laminate of the present invention, in order to remove the foreign matter 6 adhering to the surface of which is not superimposed with the dielectric sheet 3 before Symbol metal foil 2, the metal foil 2 It is preferable to supply plasma 9 to the surface.

Method for producing both sides a metal foil-clad laminate of the present invention, in order to remove the foreign matter 6 adhering to the surface of which is not superimposed with the dielectric sheet 3 before Symbol metal foil 2, the metal foil 2 It is preferable to irradiate the surface with ultraviolet rays 10.

In the present onset Ming, inverted before superimposing said insulating sheet member 3 and the other metal foil 5, up and down in a state in which the superposed slip sheet 21, 21 above and below the overlay object 20 and, thereafter, by removing the interleaf paper 21 and 21 from the overlay object 20, the said foreign matter 6 adhering to the surface of the insulating sheet material 3 is dropped on the interleaf sheet 21 is removed by it can be said is foreign matter 6 is unlikely to adhere to the surface of the metal foil 2, 5, it is capable to reduce the occurrence of dents.

  Hereinafter, the best mode for carrying out the present invention will be described.

  First, a plurality of bumps (projections) 1, 1... Are formed on the upper surface of the metal foil 2. Here, as the metal foil 2, an arbitrary conductive material having an arbitrary thickness can be used. For example, a copper foil having a thickness of 8 to 105 μm can be used. The bump 1 can be formed in a shape having a pointed tip (upper end) such as a conical shape by printing a conductive paste such as a silver paste and then making it semi-cured. The size and interval of the bumps 1 can be arbitrarily set. For example, the diameter of the bottom surface can be set to 80 to 300 μm and the height can be set to 80 to 300 μm.

  Next, the insulating sheet material 3 is placed (build-up) on the upper surface of the metal foil 2 on which the bumps 1 are formed and overlapped, and the bumps 1 are pierced through the insulating sheet material 3 from below to penetrate the insulating sheet. The tip (upper end) of the bump 1 is protruded from the upper surface of the material 3. As the insulating sheet material 3, a resin film, a prepreg (resin-impregnated base material), or the like can be used. As the resin of the insulating sheet material 3, a known material such as an epoxy resin or a phenol resin can be used, and as the base material of the prepreg, a known material such as a glass nonwoven fabric or a glass woven fabric can be used. Moreover, the thickness of the insulating sheet material 3 can also be set arbitrarily, for example, can be 20-200 micrometers. Moreover, it is preferable to make the front-end | tip of bump 1 protrude 5-20 micrometers from the upper surface of the insulating sheet material 3. FIG. In this way, the metal foil 2 on which the bumps 1 are formed and the insulating sheet material 3 are overlapped to form an overlapped product 20.

  In the present invention, as shown in FIG. 1 (a), a plurality of superposed articles 20, 20... Are stacked while being sequentially produced. Try to load. Therefore, a plurality of stacked products 20, 20... Are stacked with the interleaf paper 21 interposed between the stacked products 20, 20 adjacent to each other in the vertical direction. The slip sheet 21 is used to protect the bump 1 from damage such as cracks and chips, and to prevent the bump 1 and the insulating sheet material 3 from directly contacting the lower surface of the metal foil 2. Paper for preventing foreign matter such as conductive foreign matter from adhering. Any material can be used as the interleaving paper 21. For example, it is preferable to use a film formed by sandwiching the upper and lower surfaces of the film with gin-free paper and having a thickness of 100 to 1000 μm. 1 (a) and 1 (b), a part of the plurality of stacked objects 20, 20,.

Next, in a state where a plurality of stacked products 20, 20... Are stacked, they are conveyed to the next molding process by a conveyor or the like. Next, as shown in FIG. 1 (b), the whole of the plurality of superposed articles 20, 20,... By this reversal, the upper surface of the insulating sheet material 3 placed on the metal foil 2 faces downward, and the foreign matter 6 such as resin powder adhered to the upper surface of the insulating sheet material 3 is caused by the weight of the lower interleaf 21. Dropped on top and removed. Therefore, it becomes difficult for the foreign material 6 to enter between the metal foil 2 and the interleaving paper 21 on the upper side, and the occurrence of dents due to the foreign material 6 can be reduced. Next, as shown in FIG. 1 (c), one superposed product 20 is taken out from the load. At this time, the interleaving papers 21 and 21 are taken out in a state of being superposed on the top and bottom of the superposed product 20. Next, the upper interleaf sheet 21 is removed from the superposed product 20 taken out, and the glossy surface (shiny surface) of the upper surface of the metal foil 2 is exposed. Next, the foreign matter 6 such as resin powder attached to the upper surface of the metal foil 2 is removed. Here, as shown in FIG. 1 (d), when removing the foreign material 6, it is captured by the adhesive 7. The adhesive 7 is for adhering the foreign matter 6 to make it easier to remove, and a cloth containing a sticky substance such as pine resin can be used. For example, it is called “tag rack”. Can be used. Moreover, when removing the foreign material 6 with the adhesive 7, the foreign material 6 adhering to the upper surface of the metal foil 2 is wiped off with the adhesive 7. At this time, the pressure applied to the metal foil 2 is 0.1 to 100 kPa ( 0.01 to 1.0 kgf / cm ² ) is preferable. If the pressure applied to the metal foil 2 is less than 0.1 kPa, the removal of the foreign matter 6 may be insufficient. If the pressure applied to the metal foil 2 is greater than 100 kPa, the bumps 1 may be broken or damaged or the adhesive 7 May be transferred to the metal foil 2 to cause poor appearance. By removing the foreign matter 6 from the surface of the metal foil 2 in this way, in the next process, the foreign matter 6 is less likely to be pressure-formed in a state where it exists on the surface of the metal foil 2, and the occurrence of a dent is generated. Can be reduced.

  After removing the foreign material 6 from the surface of the metal foil 2 of the superposed product 20 as described above, the lower interleaf 21 is removed from the superposed product 20 to expose the bumps 1. Thereafter, another metal foil 5 is superposed on the surface of the superposed product 20 on which the bump 1 is formed, and build-up is performed. Thereby, the other metal foil 5 is arranged in a state in contact with the tip of the bump 1 protruding from the lower surface of the insulating sheet material 3. Next, as shown in FIG. 1 (e), a superposition of the metal foils 2 and 5 and the insulating sheet material 3 is placed between the two upper and lower forming plates 22 and 22, and then heated and pressed. By forming and hardening the insulating sheet material 3, an insulating layer is formed from the insulating sheet material 3, and the metal foils 2 and 5 are bonded and integrated with the insulating layer. Here, the conditions of the heat and pressure molding can be appropriately set according to the type and thickness of the resin of the insulating sheet material 3, for example, temperature 125 to 190 ° C., pressure 0.98 to 10.3 MPa, time It can be 90-120 minutes. In this way, a double-sided metal foil-clad laminate in which the metal foils 2 and 5 on both sides are electrically connected by the bumps 1 can be formed.

In the manufacturing method of the double-sided metal foil-clad laminate of the present invention as described above, after removing the foreign matter 6 from the superposed product 20 by the adhesive 7, before superimposing another metal foil 5 on the superposed product 20, As shown in FIG. 2, it is possible to supply plasma 9 or irradiate ultraviolet rays 10 on the surface of the metal foil 2 from which the foreign matter 6 of the overlapped product 20 has been removed. Thereby, the foreign matter 6 such as oil adhering to the surface of the metal foil 2 can be decomposed and removed by the plasma 9 or the ultraviolet ray 10, and molding defects due to the foreign matter 6 such as oil can be prevented. Here, only one of the supply of the plasma 9 and the irradiation of the ultraviolet rays 10 may be performed, or both may be sequentially performed. The supply condition of the plasma 9 can be, for example, a cleaning time of 10 minutes using a CO ₂ plasma at a vacuum degree of 1.5 Pa, and the irradiation conditions of the ultraviolet ray 10 are, for example, an ultraviolet lamp 300 nm, 300 W × The irradiation can be performed for 6, 10 minutes, but is not limited thereto.

  And in the method of the above conventional example, the appearance defect rate of the double-sided metal foil-clad laminate due to the dent is 25%, but in the present invention, the appearance failure rate of the double-sided metal foil-clad laminate is 7%. Diminished.

An example of embodiment of this invention is shown and (a)-(e) is schematic. It is the schematic which shows other embodiment same as the above. A prior art example is shown, and (a) to (c) are schematic views.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bump 2 Metal foil 3 Insulating sheet material 5 Metal foil 6 Foreign material 7 Adhesive material 9 Plasma 10 Ultraviolet rays

Claims (6)

By penetrating pierce the bumps on the insulating sheet material causes the metal foil to form a bump on the top surface overlapping the insulating sheet material, said superposition product obtained by projecting the tip of the bump on the upper surface of the insulating sheet material formed, superimposed and with other metal foil the insulation sheet so as to contact with the tip of the bump, after this, double-metal for integrating said metal foil and said insulating sheet material by press molding the method of manufacturing a foil-clad laminate, prior to superimposing the other metal foil and said insulating sheet, inverted up and down in the stacked state interleaves and below the overlay was then said overlaid A method for producing a double-sided metal foil-clad laminate, wherein the slip sheet is removed from a laminate. After reversed vertically superposed state interleaves and below the overlay material, claims and removing foreign matter adhering to the surface of which is not superimposed with the insulating sheet material of the metal foil Item 2. A method for producing a double-sided metal foil-clad laminate according to Item 1.   The method for producing a double-sided metal foil-clad laminate according to claim 2, wherein the foreign matter is captured and removed with an adhesive. When trapping and removing the foreign substance in the adhesive material, the method for producing the double-sided metal-foil-clad laminate according to claim 3, characterized in that the 0.1~100kPa the pressure applied to the metal foil. When removing the foreign matter adhering to the surface of which is not superimposed with the insulating sheet material of the metal foil, any one of claims 2 to 4, characterized in that to supply the plasma to the surface of the metal foil 1 The manufacturing method of the double-sided metal foil clad laminated board as described in a term. When removing the foreign matter adhering to the surface of the person who the not overlapped with insulating sheet material of the metal foil, any one of claims 2 to 5, wherein applying ultraviolet light to the surface of the metal foil 1 The manufacturing method of the double-sided metal foil clad laminated board as described in a term.

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