DK165040B

DK165040B - MULTIPLE CIRCUIT PLATE WITH RIGID AND FLEXIBLE AREAS

Info

Publication number: DK165040B
Application number: DK359187A
Authority: DK
Inventors: Friedrich-Wilhelm Schlitter
Original assignee: Schoeller & Co Elektronik
Priority date: 1986-07-22
Filing date: 1987-07-10
Publication date: 1992-09-28
Also published as: DK359187D0; DE3764217D1; EP0255607A3; EP0255607A2; DE3624719A1; DE3624719C2; DK165040C; EP0255607B1; ATE55531T1; DK359187A

Abstract

1. A prelaminate which may be used instead of flexible single layers in the construction of rigid-flexible circuit boards, characterized in that it consists of a plate (1) of a non-flexible (rigid) material into which flexible, adhesive-coated plastic films (2) free from edge gaps and equal in thickness to the plate (1) are inserted in the regions where the subsequent circuit board is to be flexible, the regions of the inserted flexible plastic films having to be 2 to 10 mm larger than the desired subsequent flexible regions of the circuit board.

Description

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DK 165040 BDK 165040 B

Opfindelsen angår et forlaminat, der ved opbygning af stive-fleksible kredsløbsplader kan indsættes i stedet for de fleksible enkeltlag.BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a laminate which can be inserted in the structure of rigid flexible circuit boards instead of the flexible single layers.

For nogle år siden blev der i elektronikindustri-5 en indført trykte kredsløb, der har stive og fleksible områder. Disse kredsløbsplader opbygges af stive og fleksible enkeltlag, der ved hjælp af forbindelsesfolie bliver fast sammenklæbet. Der er her tale om ikke bøjelige, f.eks. glas-epoxyharpiks, og bøjelige isolations-10 bærere, f.eks. polyimidfolie, med enkelt- eller dobbeltsidet kobberbelægning, hvori kredløbsbanerne ætses. Det stive lags form bestemmer kredsløbspladens stive del, fra hvilken det bøjelige lag fører ud og danner det bøjelige koblingsområde, der forbinder yderligere dele af 15 kredsløbet med hinanden eller udgør forbindelsen til ydre opbygninger.A few years ago, in the electronics industry-5, a printed circuit was introduced that has rigid and flexible areas. These circuit boards are made up of rigid and flexible single layers, which are fastened together by means of connecting foil. These are not flexible, e.g. glass epoxy resin, and flexible insulation carriers, e.g. polyimide foil, with single or double sided copper coating in which the orbits are etched. The shape of the rigid layer determines the rigid portion of the circuit board from which the flexible layer extends and forms the flexible coupling region which connects additional parts of the circuit to each other or forms the connection to external structures.

De bøjelige dele fremstilles ved, at man i disse områder bortbryder det stive yderlag. En sådan fremgangsmåde er f.eks. beskrevet i DE-PS 26 57 212.The flexible parts are made by breaking away the rigid outer layer in these areas. Such a method is e.g. described in DE-PS 26 57 212.

20 De bøjelige enkeltlag overdækker af fremstillings mæssige grunde i de kendte kredsløbsplader med stive og bøjelige områder hele kredsløbspladen, selvom de egentlig kun er nødvendige i den bøjelige del. Dette fordyrer sådanne kredsløbsplader, da de bøjelige enkeltlag er 25 flere gange dyrere end de stive enkeltlag.20 The flexible single layers, for manufacturing reasons, cover the known circuit boards with rigid and flexible areas throughout the circuit board, although they are really only needed in the flexible part. This expensiveens such circuit boards as the flexible single layers are 25 times more expensive than the rigid single layers.

Der er derfor opfindelsens formål at tilvejebringe et forlaminat, der ved opbygning af stive-bøjelige lederplader kan indsættes i stedet for de bøjelige enkeltlag, og som er væsentligt billigere end de hidtil 30 anvendte bøjelige enkeltlag.It is, therefore, an object of the invention to provide a laminate which can be inserted in place of the rigid flexible guide sheets in place of the flexible single layers and which is substantially cheaper than the flexible single layers used so far.

Denne opgave løses ifølge opfindelsen ved, at forlaminatet består af en plade af et ikke bøjeligt, stift materiale, i hvilket der i. områder, hvori den senere kredsløbsplade skal være bøjelig, er indført bøje-35 lige, klæbestofovertrukne kunststoffolier fri for spalter langs randene og med samme tykkelse, idet det ind- 2This task is solved according to the invention in that the laminate consists of a sheet of non-flexible rigid material, in which flexible, adhesive-coated plastic films free of gaps along the edges are introduced into areas in which the later circuit board must be flexible. and with the same thickness as it contains 2

DK 165040 BDK 165040 B

førte bøjelige kunststoffolies område er noget større end det ønskede senere bøjelige område af kredsløbspladen.the area of the flexible flexible film led is somewhat larger than the desired later flexible area of the circuit board.

Ved anvendelsen af sådanne forlaminater bliver 5 fremstilling af kredsløbsplader med stive-bøjelige områder gjort væsentligt billigere, sålænge de bøjelige områder af den færdige kredsløbsplade ikke udgør mere end 50% af hele kredsløbet, idet det stive materiale er væsentligt billigere end den bøjelige kunststoffolie.In the use of such laminates, the manufacture of circuit boards with rigid flexible areas is made substantially cheaper as long as the flexible areas of the finished circuit board do not constitute more than 50% of the entire circuit, the rigid material being substantially cheaper than the flexible plastic film.

10 Fremstillingen af sådanne forlaminater sker på den måde, at man i såkaldte pre-pregs, det er glasmåtter med ikke ophærdet epoxyharpiks, med et værktøj stanser eller skærer udsparinger, der er noget større end de ønskede bøjelige dele af kredsløbspladen. Med samme 15 værktøj bliver komplementære stykker udskåret af en klæbemiddelovertrukket bøjelige kunststoffolie og uden spalter langs randene indsat i pre-pregene, idet pre-preg og kunststoffolie vælges således, at tykkelsen af pre-preget i presset tilstand har samme tykkelse som den 20 klæbes tof overtrukne kunsts tof folie. På henholdsvis over-og undersiden af dette basismateriale lægges derpå en kobberfolie og denne sammensætning presses ved tryk og temperatur til et laminat.The manufacture of such laminates is done in such a way that in so-called pre-pregs, that is glass mats with non-cured epoxy resin, with a tool, cut or cut recesses which are somewhat larger than the desired flexible parts of the circuit board. With the same tool, complementary pieces are cut from an adhesive-coated flexible plastic film and without slits along the edges inserted into the pre-embossing, selecting the pre-embossing and plastic foil so that the thickness of the pre-embossed in the pressed state is the same thickness as the adhesive. coated art tow foil. A copper foil is then placed on the top and bottom of this base material and this composition is pressed into a laminate at pressure and temperature.

De indpassede bøjelige kunststoffolierområder må 25 være nogle milimeter, fortrinsvis 2 til 10 mm, større end de senere bøjelige områder således, at en upåklagelig klæbning af den bøjelige kunststof folie i det stive område sikres.The fitted flexible plastic foil regions must be some millimeters, preferably 2 to 10 mm, larger than the later flexible areas so as to ensure impeccable adhesion of the flexible plastic foil in the rigid area.

Fig. 1 og 2 viser skematisk et eksempel på en ud-30 førelsesform for forlaminatet ifølge opfindelsen i længde- og tværsnit. I udsparingen i en stiv plade 1, f.eks. af glas-epoxyharpiks, er en bøjelig klæbemiddel overtrukket kunststoffolie 2, f.eks. af polyimid eller polyester, indført uden spalter langs kanten. Disse for-35 laminater er derpå sædvanligvis forsynet med et kobberlag 3 på over- og undersiden.FIG. 1 and 2 show schematically an example of an embodiment of the front laminate according to the invention in longitudinal and transverse sections. In the recess in a rigid plate 1, e.g. of glass epoxy resin, is a flexible adhesive coated plastic wrap 2, e.g. of polyimide or polyester, inserted without gaps along the edge. These precast laminates are then usually provided with a copper layer 3 on the upper and lower sides.

Claims

DK 165040 B Forlaminate which can be inserted in place of rigid flexible circuit boards in place of the flexible single layer, characterized in that it consists of a plate (1) of non-flexible rigid material, in which in the areas in which the later circuit board must be flexible are inserted flexible, with adhesive-coated coastal film (2) without slits along the edge and of the same thickness, whereby the area of the inserted flexible plastic film must be somewhat larger than the desired later flexible area of the circuit board .