U.S. patent application number 12/474739 was filed with the patent office on 2009-10-08 for process for manufacturing printed circuit boards and a machine for this purpose.
This patent application is currently assigned to Chemplate Materials, S.L.. Invention is credited to Jose Antonio Cubeiro Gonzalez, Victor LAZARO GALLEGO.
Application Number | 20090250456 12/474739 |
Document ID | / |
Family ID | 33041267 |
Filed Date | 2009-10-08 |
United States Patent
Application |
20090250456 |
Kind Code |
A1 |
LAZARO GALLEGO; Victor ; et
al. |
October 8, 2009 |
PROCESS FOR MANUFACTURING PRINTED CIRCUIT BOARDS AND A MACHINE FOR
THIS PURPOSE
Abstract
Process and machine for manufacturing printed circuit boards
wherein a press packet comprised of at least two press plates of
metal material between which is arranged a printed circuit board
composition formed by one or more metal sheets, by one or more
layers of insulating material impregnated with polymerizable resins
and/or by one or more printed circuit boards with an engraved image
of a circuit, are arranged between the press plates of a press and
is pressed, subjecting said press packet to the action of a
variable induction magnetic field which generates induced currents
in each metal plate and sheet of the press packet, causing the
heating of said plates and sheets, in turn causing the heating by
thermal conduction of the layers of insulating material, melting
and liquefying the resins in said layers of insulating material and
adhering the insulating material to the metal sheets, so that, on
raising the temperature even more, the polymerizable resins in the
layers of insulating material are then polymerized, resulting,
after the cooling of the press packet, in one or more rigid boards
suitable for making printed electronic circuits. The machine to
carry out the above process comprises a variable induction magnetic
field generating device adapted to generate induced currents in the
press packet's metal plates and sheets, causing them to heat, and
means of controlling the operation of the magnetic field generating
device and controlling the temperature and pressure to which the
press packet is subjected.
Inventors: |
LAZARO GALLEGO; Victor;
(Santa Perpetua de Mogoda, ES) ; Cubeiro Gonzalez; Jose
Antonio; (Santa Perpetua de Mogoda, ES) |
Correspondence
Address: |
SUGHRUE MION, PLLC
2100 PENNSYLVANIA AVENUE, N.W., SUITE 800
WASHINGTON
DC
20037
US
|
Assignee: |
Chemplate Materials, S.L.
Santa Perpetua de Mogoda
ES
|
Family ID: |
33041267 |
Appl. No.: |
12/474739 |
Filed: |
May 29, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10549040 |
Sep 15, 2005 |
7565736 |
|
|
PCT/EP2004/002072 |
Mar 2, 2004 |
|
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12474739 |
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Current U.S.
Class: |
219/633 ;
219/635; 219/659; 219/660 |
Current CPC
Class: |
H05K 3/022 20130101;
Y10T 29/49128 20150115; B32B 15/14 20130101; H05K 2203/101
20130101; B32B 2260/021 20130101; B32B 2457/08 20130101; H05K
3/4611 20130101; Y10T 29/49155 20150115; B32B 2310/0812 20130101;
B32B 37/06 20130101; B32B 2260/046 20130101; B32B 37/04 20130101;
Y10T 29/49126 20150115; B32B 2309/68 20130101 |
Class at
Publication: |
219/633 ;
219/635; 219/660; 219/659 |
International
Class: |
H05B 6/06 20060101
H05B006/06; H05B 6/10 20060101 H05B006/10 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 27, 2003 |
ES |
200300717 |
Claims
1. An apparatus comprising: an upper press plate which is capable
of vertical displacement; a lower press plate arranged coaxially
with respect to the upper press plate, said lower plate being
capable of vertical displacement, the upper and lower plates
lacking any device to provide heat and being adapted to receive a
press packet between them; a variable induction magnetic field
generation device adapted to apply a variable induction magnetic
field in a transverse direction of the press packet, said variable
induction magnetic field running generally parallel to the planar
surfaces of the press packet and generating induced currents
causing heating in the press packet; a control circuit which
controls the frequency and voltage applied to the electromagnetic
field generation device, the temperature of the press packet, and
the pressure to which the press packet is subjected.
2. The apparatus of claim 1, further comprising temperature probes
adapted to be mounted on the press packet.
3. The apparatus according to claim 1, further comprising a
vacuuming part which produces a vacuum inside a closed structure of
the apparatus.
4. The apparatus according to claim 1, wherein the variable
induction field generation device is provided without a magnetic
core, and is formed by induction coils within which the upper press
plate and the lower press plate are arranged.
Description
[0001] This is a Divisional Application of U.S. application Ser.
No. 10/549,040 filed Sep. 15, 2005, which is a National Stage entry
of PCT/EP2004/002072 filed Mar. 2, 2004 which claims priority from
ES P 200300717 filed Mar. 27, 2003. The disclosures of each of the
above applications are incorporated herein by reference in their
entirety.
TECHNICAL FIELD OF THE INVENTION
[0002] The aim of the invention is a process for manufacturing
printed circuit boards and a machine to carry out said process.
BACKGROUND OF THE INVENTION
[0003] Printed circuit boards may take on multiple functional
compositions, essentially concerning the number of metal sheets
with an image of the circuit they form. So, for example, and among
other forms, a board composition is initially formed from a metal
sheet and a layer of insulating material impregnated with
polymerizable resin on which, once the resins are polymerized and
the board is cooled until it is hard, an engraved image of the
circuit is formed on the metal sheet; another board composition is
formed initially by two metal sheets between which there are one or
more layers of insulating material; and a third composition for a
printed circuit board is initially formed by two metal sheets
between which there are two layers of insulating material separated
by a printed circuit board provided on both faces with the already
engraved image of the circuit.
[0004] In general, the process of polymerizing the resins in the
layers of insulating material is carried out by subjecting the
board whose composition has been disclosed to pressure at the same
time as the temperature is raised until it reaches polymerization
temperature. To do this, presses are used which are essentially
differentiated by the method of heating the boards. One type of
press includes means of heating arranged on the press plates of the
press, so that the board is heated during pressing by thermal
conduction. Another type of press includes means of heating based
on passing an electric current supplied by a power
source--generally direct current--through the board's sheets; in
this case, the metal sheets are arranged continuously in order to
make it possible for the electric current to pass through.
[0005] There are drawbacks with the types of press disclosed above.
In presses wherein the means of heating are arranged on the press
plates, the rate of temperature increase and the maximum
temperatures that can be reached are very limited, which leads to
low productivity. And, in presses where the means of heating are
based on passing an electric current through the board's metal
sheets, problems of electrical insulation between these and
intermediate press plates arise.
EXPLANATION OF THE INVENTION
[0006] In the process for manufacturing printed circuit boards
which is the object of the invention, a press packet comprising at
least two press plates of metal material between which are arranged
a printed circuit board composition formed by one or more metal
sheets, one or more layers of insulating material impregnated with
polymerizable resins and/or by one or more printed circuit boards
with an engraved image of the circuit, are arranged between the
press plates of a press, and it is pressed.
[0007] The process is essentially characterized in that,
maintaining pressure on the packet, it comprises the steps of
i) subjecting the press packet to the action of a variable magnetic
induction field which generates induced currents in each of the
press packet's metal plates and sheets that heat said plates and
sheets, heating, in turn, the layers of insulating material by
thermal conduction; ii) raising the temperature in the press packet
until the resins in the layers of insulating material melt,
liquefying and flowing, and providing adhesion between the layers
of insulating material and the metal sheets; iii) raising the
temperature in the press packet until it exceeds that of the
previous phase ii), so that the polymerizable resins in the layers
of insulating material are polymerised; iv) proceeding to cool the
press packet until the layers of insulating material have hardened;
and finally removing the press packet from between the press plates
of the press and separating the press plates from the rigid board
or boards obtained.
[0008] It is also characteristic of the process that the printed
circuit board or boards with an engraved image of the circuit that
may form part of the press packet composition are obtained
according to the invention process.
[0009] Another characteristic of the process is that the metal
sheets of the press packet are made of copper and/or aluminium.
[0010] According to another aspect of the invention, the layers of
insulating material are formed from fibre glass paper and/or
material impregnated with epoxy resins, polyamides, phenolic resins
or fluoropolymers (PTFE).
[0011] In accordance with another characteristic of the invention
process, the press packet is vacuum pressed.
[0012] The machine for the invention process comprises a closed
structure provided with at least one press unit comprised of an
upper press plate capable of vertical displacement in both
directions, activated by means of propulsion, and by a lower press
plate arranged coaxially with respect to the upper press plate,
fixed to the press structure or capable of vertical displacement in
both directions, the upper and lower plates lacking any device to
provide heat and being adapted to receive a press packet between
them, in accordance with the invention process.
[0013] In essence, the machine is characterized in that it
comprises a variable induction magnetic field generating device,
adapted to generate induced currents in the press packet's metal
plates and sheets causing them to heat, and means of controlling
the operation of the magnetic field generating device, which
essentially affect the frequency and voltage applied to the device
and the temperatures reached in the press packet, and means of
controlling the pressure to which it is subjected.
[0014] According to a preferred embodiment, the machine comprises
means for producing a vacuum inside the closed structure.
[0015] Another characteristic of the invention is that the machine
is provided with a variable induction field generation device,
without a magnetic core, formed by induction coils within which the
upper press plate and the lower press plate are arranged.
[0016] The characteristics of the invention process and machine
provide an innovative solution to the problems created by both the
known processes and machines for manufacturing printed circuit
boards. With the invention process, the heating of the press
packet's metal sheets by electromagnetic induction has the
following advantages: it produces uniform heating in the press
packet, and it is virtually possible to achieve any rate of
temperature increase of the press packet and any polymerization
temperature necessary for the resins used. The temperature reached
by the press packet is easily controlled and regulated by
controlling the voltage and/or frequency of the electrical power
applied to the circuit generating the magnetic field. It can be
applied to any press packet composition without loss of performance
concerning temperature or temperature regulation thereof; and it
does not require intermediate press plates to be equipped with
electrical insulation, as occurs in those embodiments of presses
based on passing a current through the metal plates forming the
press packet.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] By way of a non-limiting example, the attached drawings
illustrate various compositions of printed circuit boards which can
be obtained using the invention process as well as an embodiment of
the machine for the invention process. In said drawings:
[0018] FIGS. 1 to 5 are schematic section views of respective
compositions of press packets; and
[0019] FIG. 6 is a diagrammatic section representing a machine for
the invention process.
DETAILED DESCRIPTION OF THE DRAWINGS
[0020] In the following description of the invention process and
machine therefor, identical reference numbers are used by way of
simplification to designate identical or similar parts.
[0021] FIG. 1 represents a first press packet 10, comprising two
press plates, an upper press plate 11 and a lower press plate 12
respectively, between which is arranged a printed circuit board
composition formed by a first metal sheet 13 and a second metal
sheet 14 separated from one other by three layers of insulating
material 15 impregnated with polymerizable resins. Preferably, the
metal layers 13 and 14 are made of copper and the layers of
insulating material 15 are made of fibre glass material impregnated
with epoxy resins.
[0022] FIG. 2 represents a second press packet 20, comprising three
press plates, an upper press plate 11, an intermediate press plate
21 and a lower press plate 12 respectively. Between the upper press
plate 11 and the intermediate press plate 21 a printed circuit
board composition is arranged formed by a first metal sheet 13 and
a second metal sheet 14 separated from one other by three layers of
insulating material 15 impregnated with polymerizable resins, all
of them in a similar form to the printed circuit board composition
detailed in FIG. 1, and a printed circuit board composition similar
to the one arranged between the upper press plate 11 and the
intermediate press plate 21 is arranged between the intermediate
press plate 21 and the lower press plate 12.
[0023] FIG. 3 represents a third press packet 30, comprising two
press plates, an upper press plate 11 and a lower press plate 12
respectively, between which is arranged a printed circuit board
composition formed by a first metal sheet 13, two layers of
insulating material 15 impregnated with polymerizable resins, a
printed circuit board 31 with its upper and lower faces provided
with respective engraved circuit images, two layers of insulating
material 15 impregnated with polymerizable resins and a second
metal sheet 14.
[0024] FIG. 4 represents a fourth press packet 40, comprising three
press plates, an upper press plate 11, an intermediate press plate
21 and a lower press plate 12 respectively. Between the upper press
plate 11 and the intermediate press plate 21, a printed circuit
board composition is arranged formed by a first metal sheet 13, two
layers of insulating material 15 impregnated with polymerizable
resins, a printed circuit board 31 with its upper and lower faces
provided with respective engraved circuit images, two layers of
insulating material 15 impregnated with polymerizable resins and a
second metal sheet 14, all this in a similar way to the printed
circuit board composition detailed in FIG. 3; and a printed circuit
board similar to the one arranged between the upper press plate 11
and the intermediate press plate 21 is arranged between the
intermediate press plate 21 and the lower press plate 12.
[0025] FIG. 5 represents a fifth press packet 50, comprising four
press plates, an upper press plate 11, a first intermediate press
plate 21, a second intermediate press plate 21 and a lower press
plate 12 respectively. Between each pair of superimposed press
plates, i.e. between press plates 11 and 21; 21 and 51; and 51 and
12, a printed circuit board composition is arranged, formed by a
first metal sheet 13 and a second metal sheet 14 separated by three
layers of insulating material 15 impregnated with polymerizable
resins, all in a similar way to the printed circuit board
compositions shown in FIGS. 1 and 2. It should be noted that the
continuity between the first metal sheets 13 of each of the
compositions and the continuity between the second metal sheets 14
is in no way necessary for the application of the invention
process, but rather is given by way of example of the application
of the invention process in cases where the press packets are
formed in the way shown in FIG. 5, i.e. providing physical
continuity between the first and second metal sheets.
[0026] The press plates used to carry out the process are made of
metal material, such as aluminium or steel, and preferably magnetic
steel.
[0027] Likewise, the result of the process, according to the
invention, is optimum when the metal sheets used to produce the
circuit boards are made of copper and/or aluminium.
[0028] The faces of the metal sheets intended to be in contact with
the layers of insulating material are mechanically or chemically
treated to increase their roughness and adherence to said layers of
insulating material.
[0029] Alternatively, the surface of the metal sheets used and
intended to be in contact with the layers of insulating material
may be impregnated with adhesives or resins, also to increase the
adherence of the metal sheets to the insulating material used.
[0030] As indicated above, in FIGS. 1 to 5, the application of the
invention process has been represented by way of example, but there
are many other possible configurations providing different
embodiments of press packets. The invention process is applicable
to all of them and, once the press packet has been formed and
subjected to pressure by the machine of the invention, as will be
described below by way of example, the following steps are taken:
i) subjecting the press packet 10; 20; 30; 40; 50 to the action of
a variable magnetic field that generates induced currents in the
press plates 11; 12; 21; 51; in the metal sheets 13; 14 and in the
printed circuit boards with images of circuits 31, heating them
and, by thermal conduction, heating the layers of insulating
material 15; ii) raising the temperature in the press packet 10;
20; 30; 40; 50 until the resins in the layers of insulating
material 15 melt and said material adheres to the metal sheets;
iii) raising the temperature of the press packet until the resins
in the layers of insulating material 15 polymerize; and iv)
proceeding to cool the press packet 10; 20; 30; 40; 50 until the
layers of insulating material 15 harden, removing the press packet
from between the press plates of the press and separating the press
plates 11; 12; 21; 51 from the rigid board or boards obtained.
[0031] The machine of the invention represented diagrammatically in
FIG. 6 comprises a closed structure 60 provided with means 61 for
producing a vacuum inside it and a vacuum gauge 62. Inside the
structure 60, there is a press unit comprising an upper press plate
63 capable of vertical displacement in both directions; a lower
press plate 64, arranged coaxially with respect to the upper press
plate 63, which in this example of embodiment is fixed to the
structure 60, although it is understood that, as a variant of
embodiment not represented, said lower plate may be capable of
vertical displacement in both directions; and means of propulsion
of the upper press plate 63 comprising a cylinder 65 provided with
a piston 66 whose rod 67 is fixed to the upper press plate 63, all
adapted to receive a press packet 70 between the upper plate 63 and
the lower one 64, with a printed circuit board composition such as
those given in FIGS. 1 to 5, or any other possible one. In this
example of embodiment, a single press unit is shown, although it is
understood that the closed structure 60 may contain more than one
press unit, for example, two or more press units, and that their
number will be dictated, among other factors, by the volume of
printed circuit board production required.
[0032] FIG. 6 shows that the machine of the invention is provided
with a variable induction magnetic field generation device 68,
without a magnetic core, basically formed by induction coils within
which the upper press plate 63, the press packet 70 and the lower
press plate 64 are arranged. In addition, the magnetic field
generation device 68 is provided with means of control 69, which
are essentially intended to control the frequency and power supply
voltage to these coils, which enables the temperatures reached by
the press packet 70 to be altered.
[0033] The times and temperatures required to polymerize the resins
which may be used in the manufacturing process of the boards depend
on the composition of the resins and the pressure applied to the
press packet. For this reason, the machine is provided with a
pressure regulator 71 and with one or more temperature probes 72.
The information obtained by the pressure regulator and temperature
probes is used to govern the machine's means of control 69.
* * * * *