U.S. patent application number 09/745690 was filed with the patent office on 2002-02-28 for circuit-like metallic foil sheet and the like and process for producing them.
Invention is credited to Uchibori, Shinya.
Application Number | 20020025416 09/745690 |
Document ID | / |
Family ID | 27408759 |
Filed Date | 2002-02-28 |
United States Patent
Application |
20020025416 |
Kind Code |
A1 |
Uchibori, Shinya |
February 28, 2002 |
Circuit-like metallic foil sheet and the like and process for
producing them
Abstract
A resonant tag is provided that comprises a circuit-like
metallic foil pattern that is adhered to a dielectric film prepared
from a liquid resin by a coating process. The circuit-like metal
foil pattern on one side of the dielectric film may be so aligned
with the circuit-like metal foil pattern on the other side of the
dielectric film as to form a capacitor with the dielectric film.
The dielectric film may have openings therein configured similarly
to and aligned with openings in the circuit-like metal foil, and
the configuration of the circuit-like metal foil pattern and
dielectric film may be generally spiral in configuration. An
adhesion adhesive may be coated on predetermined portions of a face
of a resonant tag base so as to leave uncoated portions between the
coated portions, and a release paper is applied to the adhesion
adhesive, the width of the uncoated portions being such as to avoid
the generation of static electricity when the release paper is
peeled from the adhesion adhesive.
Inventors: |
Uchibori, Shinya;
(Hiroshima-shi, JP) |
Correspondence
Address: |
James R. Haller
Fredrikson & Byron, P.A.
1100 International Centre
900 2nd Ave. S.
Minneapolis
MN
55402-3397
US
|
Family ID: |
27408759 |
Appl. No.: |
09/745690 |
Filed: |
December 22, 2000 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09745690 |
Dec 22, 2000 |
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08898077 |
Jul 22, 1997 |
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Current U.S.
Class: |
428/209 ;
156/230; 216/13; 340/572.3; 428/41.8; 428/458 |
Current CPC
Class: |
B32B 15/08 20130101;
G08B 13/244 20130101; Y10S 428/901 20130101; B32B 15/12 20130101;
Y10T 428/31681 20150401; Y10T 428/24917 20150115; G08B 13/2414
20130101; B32B 2519/02 20130101; Y10T 428/31544 20150401; Y10T
428/1476 20150115; G08B 13/2437 20130101; B32B 15/04 20130101 |
Class at
Publication: |
428/209 ;
428/458; 428/41.8; 340/572.3; 216/13; 156/230 |
International
Class: |
B32B 009/00; G08B
013/14; G08B 013/24 |
Claims
What is claimed is:
1. A process for fabricating a circuit-like metallic foil sheet for
resonant tag and the like, said process using a laminate comprising
a carrier sheet such as a paper or a plastic film adhered thereto a
metallic foil as the base material, and said process comprising:
patterning the metallic foil of said laminate using a stamping die
to provide a predetermined circuit-like pattern on the metallic
foil; disposing the surface of a support such as a plastic film and
the like opposed to the side of said laminate having thereon the
metallic foil; and transferring the circuit-like metallic foil to
the surface of the support by heating said circuit-like patterned
portion from the carrier sheet side of said laminate or from the
support side.
2. A process for fabricating a circuit-like metallic foil sheet as
claimed in claim 1, wherein, said process uses, as the base
material, a laminate comprising a carrier sheet adhered thereto a
metallic foil and a coating of a thermal adhesive resin formed
further thereon, and said process comprising: patterning the
metallic foil of said laminate using a stamping die to provide a
predetermined circuit-like pattern on the metallic foil; disposing
the surface of a support opposed to the side of said laminate
havint thereon the metallic foil; and transferring the circuit-like
metallic foil to the surface of the support by heating said
circuit-like patterned portion from the carrier sheet side of said
laminate or from the support side.
3. A process for fabricating a circuit-like metallic foil sheet as
claimed in claim 1, wherein, said process uses a laminate
comprising a carrier sheet adhered thereto a metallic foil as the
base material, and said process comprising: patterning the metallic
foil of said laminate using a stamping die to provide a
predetermined circuit-like pattern on the metallic foil; disposing
opposed to the side of said laminate having thereon the metallic
foil, the surface of a support which itself is thermal adhesive or
which has thereon a coating of a thermal adhesive; and transferring
the circuit-like metallic foil to the surface of the support by
heating said circuit-like patterned portion from the carrier sheet
side of said laminate or from the support side.
4. A process for fabricating a circuit-like metallic foil sheet,
said processing comprising: providing a predetermined circuit-like
pattern on a metallic foil of a first laminate comprising a carrier
sheet adhered thereto the metallic foil, by means of patterning
using a stamping die; superposing on said patterned first laminate,
a second laminate comprising a carrier sheet adhered thereto a
metallic sheet being patterned by means of patterning using a
stamping die; and heating said circuit-like patterned portions form
the carrier sheet side of either or both of the first and the
second laminates, thereby forming circuit-like metallic foils on
both sides of said support with hot-melt adhesive films being
interposed therebetween.
5. A process for fabricating a circuit-like metallic foil sheet as
claimed in claim 1, wherein the metallic foils are adhered to the
carrier sheets using an easily removable adhesive.
6. A process for fabricating a circuit-like metallic foil sheet as
claimed in claim 5, wherein the adhesive used for adhering the
metallic foils to the carrier sheets is characterized in that it
comprises a blend of an adhesion adhesive and a curing agent, and
that the adhesion force thereof decreases by heating.
7. A process for fabricating a circuit-like metallic foil sheet as
claimed in claim 1, wherein the metallic foil is a 3 to 150 .mu.m
thick foil of a metal such as aluminum, copper, or stainless
steel.
8. A process for fabricating a circuit-like metallic foil sheet as
claimed in claim 1, wherein the metallic foil is a 10 to 60 .mu.m
thick foil of a metal such as aluminum, copper foil, or stainless
steel.
9. A process for fabricating a circuit-like metallic foil sheet as
claimed in claim 1, wherein the support is a dielectric.
10. A sheet comprising a circuit-like metallic foil obtained
according to a process as claimed in claim 1.
11. A process for fabricating a resonant tag using a dielectric
plastic film or a dieletric resin film as the support, said process
comprising forming a resonant circuit on both sides of the support
by transferring a circuit-like metallic foil according to a process
as claimed in claim 1.
12. A process for fabricating a resonant tag as claimed in claim
11, wherein, the support is a dielectric plastic film or a
dielectric resin film provided previously thereto a hole or a notch
at a predetermined position for connecting the metallic foil
circuits that are to be provided on both the surface and the back
of the support.
13. A process for fabricating a resonant tag, comprising:
providing, by means of patterning using a stamping die, a
predetermined circuit-like pattern on a metallic foil of a first
laminate comprising a carrier sheet adhered thereto the metallic
foil and having further thereon a hot-melt adhesive dielectric
resin film; superposing on said patterned first laminate, a second
laminate comprising a carrier sheet adhered thereto a metallic
sheet being patterned by means of patterning using a stamping die;
and heating said circuit-like patterned portions from the carrier
sheet side of either or both of the first and the second laminates,
thereby forming circuit-like metallic foils on both sides of said
support with hot-melt adhesive dielectric resin films interposed
therebetween.
14. A process for fabricating a resonant tag as claimed in claim
13, wherein a second laminate comprising a thermal adhesive
dielectric resin film formed on the surface of the metal foil is
used.
15. A resonant tag fabricated according to a process as claimed in
claim 11.
16. A resonant tag comprising a circuit-like metallic foil being
adhered to either or both sides of a dielectric film prepared from
a liquid resin by a coating process.
17. A resonant tag as claimed in claim 16, wherein the dielectric
resin film is provided on one side of the metallic foil and in the
same shape as that of the circuit-like metallic foil.
18. A resonant tag as claimed in claim 17, wherein the dielectric
resin film is laminated on one side of the metallic foil and has an
area corresponding to that of a shape defined by the outer
periphery of the circuit-like metallic foil.
19. A resonant tag as claimed in claim 16, wherein the dielectric
resin film is made of an adhesive resin.
20. A resonant tag comprising two or more laminates of circuit-like
metallic foils having on at least one side thereof a dielectric
resin film prepared from a liquid resin by a coating process, said
metallic foils being laminated using the dielectric resin coating
as an adhesive.
21. A resonant tag in which an adhesion adhesive is coated on at
least one face of a resonant tag base and a release paper is
applied on the upper face of the adhesive-coated base, the resonant
tag characterized in that the adhesion adhesive is coated in such a
manner that noncoated portion of the adhesion adhesive is provided
at appropriate width.
22. A resonant tag claimed in claim 21, wherein the noncoated
portion is in a linear shape or a lattice shape.
23. A method for deactivating resonant frequency characteristics of
the resonant tag as claimed in claim 16, wherein a short-circuit is
caused to generate at a portion such as a bent portion of a coil
circuit which is electrically weak so as to destroy a resonant
circuit, by sending strong resonant frequencies to the resonant
circuit.
24. A method for deactivating resonant frequency characteristics as
claimed in claim 23, wherein the resonant tag is a tag in which the
coil circuits of the resonant circuit are in correspondence with
each other and laminated to a dielectric film so that the coil
circuits sandwich the dielectric film.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of Invention
[0002] The present invention relates to a resonant tag equipped
with a resonant frequency circuit which resonates with a radio wave
transmitted at a particular frequency from a detector, and also
relates to processes for producing resonant tag and for fabricating
a circuit-like metallic foil sheet for a resonant tag and the
like.
[0003] 2. Description of Prior Art
[0004] As is well known, resonant tag is a tag equipped with a
resonant circuit which resonates with a radio wave transmitted at a
particular frequency. Thus, when the resonant tag is brought into
an area in which the radio wave of the particular frequency is
transmitted, the resonant tag readily reacts to operate a buzzer or
an alert lamp of a detector. Thus, to avoid shoplifting, the
resonant tags are attached to goods and the like in department
stores, discount stores, rental shops for video tapes, compact disk
(CD) shops, etc. When the payment is settled at the cashier, the
resonant tag is removed from the goods or the resonant circuit of
the resonant tag is destroyed. However, if a shop's item is passed
through a gate equipped with a particular detector without
finishing the payment, the resonant tag attached to the item
activates a buzzer, a lamp, etc., to give off an alert signal.
[0005] Basically, a resonant tag is composed of a plastic film (as
a dielectric), having a spiral (or a coil-shaped) circuit
(hereinafter referred to as a "coil circuit") on at least one side
of the film, and a circuit for use as an electrode plate of a
capacitor or another coil circuit which functions also as a
capacitor on the other side of the film. If necessary, the resonant
tag is laminated on a sheet of a base material such as a paper.
[0006] A typical resonant tag is illustrated in FIG. 6. Referring
to FIG. 6, a resonant tag comprises a plastic film 22 which
functions as a dielectric, a coil circuit 23 provided with a
metallic foil, and a metallic foil circuit 24 for a capacitor
electrode plate. The coil circuit 23 comprises a capacitor
electrode plate section 23A on one end thereof and a circuit
terminal section 23B on the other end thereof. The metallic foil
circuit 24 for the capacitor electrode plate also comprises a
capacitor electrode plate section 24A on one end thereof and a
circuit terminal section 24B on the other end thereof corresponding
to the coil circuit 23. The circuit terminal sections 23B and 24B,
which are formed by sandwitching the plastic film 22, are connected
with each other to form a resonant circuit by destroying the layer
of the plastic film 22 using a mechanical means such as pressing. A
complete resonant tag is obtained in this manner.
[0007] In addition to a resonant tag above, there is also proposed
a resonant tag having no capacitor electrode section formed on the
end portion of the coil circuit. In the proposed structure, coil
circuits are formed on both sides of a plastic film in
correspondence with each other to utilize the circuit itself as the
capacitor electrode plate.
[0008] A resonant circuit is composed of a resistance R, an
inductance L, and a capacitance (capacity of capacitor) C. The
capacitance C is formed by providing a metallic foil such as a coil
circuit, on both sides of a plastic (resin) film as a dielectric,
and the resistance R is provided by the metallic foil constituting
the circuit. Thus, to obtain a resonant tag with a predetermined
resonant frequency, the constitution of the materials should be
determined as to enable a circuit with strict accuracy in dimension
and tolerance.
[0009] In the light of the aforementioned circumstances, the coil
circuits have been formed conventionally by using, as the base
material, a plastic film (a dielectric) laminated on either or both
sides thereof a metallic foil such as an aluminum foil. In the same
manner as that for fabricating a printed circuit board, the
metallic foil on the plastic film are patterned into the circuit by
first printing the predetermined pattern using an etching-resistant
ink and then etching the printed metallic foil using a chemical
such as an acidic or an alkaline solution. Otherwise, the coil
circuits are formed by means of photoresist etching.
[0010] However, the etching process using a chemical not only
consumes time in dissolving the metallic foil, but also has
problems yet to solve concerning the post treatment of the waste
etching solution.
[0011] Concerning the plastic films for the dielectric, extruded
films of polyethylene and the like have been used conventionally.
Because extruded plastic films are under various constraints
attributed to the production process subject to various conditions
such as the slit width of the molding die and the extrusion
pressure applied to the resin, films with limited thickness and
tolerance in thickness can be obtained. More specifically, the
plastic films obtained to present by extrusion molding are
problematic in that a film below a certain thickness cannot be
obtained, i.e., there is limitation in lower-limit under molding,
and that the tolerance in thickness cannot be reduced beyond a
certain limit. A plastic film thus obtained is laminated with a
metallic foil by either thermal pressing the extruded film while it
is in a semimolten state with a metallic foil, or adhering the
extruded film with a metallic foil using an adhesive. At any rate,
both methods cannot yield stably a laminate comprising a dielectric
layer of uniform thickness. Furthermore, because of the inherently
strong covering power of the molded plastic film, the connection
between the circuits on the surface and the back of the plastic
film cannot be readily formed, or the resonant circuit once
established cannot be easily destroyed, i.e., deactivation of
resonant frequency characteristics is hard. These are other
problems in using the conventional extruded plastic films.
[0012] Prior art processes for fabricating printed circuit boards
propose stamping out a thick metallic foil into a predetermined
circuit pattern and adhering the resulting circuit to a substrate.
This process, however, is not suitable for resonant tags and the
like because a flexible board cannot be obtained from a thick
metallic foil. A process for fabricating a flexible circuit
proposes die stamping, which comprises adhering a metallic foil to
a substrate and stamping out the metallic foil into a predetermined
circuit pattern, and peeling off the metallic foil from the
unnecessary portions. However, this process is disadvantageous in
that it excludes the use of a metallic foil not strong enough for
the peeling off, and that the peeling efficiency is greatly
impaired if unnecessary portion is discontinuous.
SUMMARY OF THE INVENTION
[0013] Accordingly, an object of the present invention is to
overcome the aforementioned problems in prior art, and to provide,
by a simple fabrication process, a resonant tag having a stable
resonant frequency characteristics.
[0014] Another object of the present invention is to provide, with
high efficiency and without utilizing an etching process, a
resonant tag having a stable resonant frequency characteristics and
a circuit-like metallic foil for use in circuit boards of various
types of electric appliances, heaters, etc., in which a wiring
circuit similar to that used in resonant tag is used.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is an exploded perspective view of a resonant tag
according to an embodiment of the present invention;
[0016] FIG. 2 is an exploded perspective view of a resonant tag
according to another embodiment of the present invention;
[0017] FIG. 3 is an exploded perspective view of a resonant tag
according to a still other embodiment of the present invention;
[0018] FIG. 4 is a perspective view of a resonant tag according to
a yet other embodiment of the present invention, in which an
electrically conductive resin film is partially provided to the
resin film;
[0019] FIG. 5 is an exploded perspective view of a resonant tag
according to an embodiment of the present invention, in which a
plurality of coil-like metallic foils are laminated;
[0020] FIG. 6 is an exploded perspective view of a prior art
resonant tag;
[0021] FIGS. 7A to 7G are a schematically drawn diagram showing the
cross section views of the step sequential members obtained during
the fabrication of a resonant tag, which is provided as an
explanatory means for a process according to an embodiment of the
present invention;
[0022] FIG. 8 is a perspective view of a fabrication apparatus for
use in a process according to an embodiment of the present
invention;
[0023] FIG. 9 is a perspective view of a part of the fabrication
apparatus illustrated in FIG. 8, showing an application of the
apparatus;
[0024] FIGS. 10A to 10G are a schematically drawn diagram showing
the cross section views of the step sequential members, provided as
an explanatory means for a process according to another embodiment
of the present invention;
[0025] FIG. 11 is a perspective view of another fabrication
apparatus for use in a process according to another embodiment of
the present invention;
[0026] FIG. 12 is a perspective view of a still other fabrication
apparatus for use in a process according to a still other
embodiment of the present invention;
[0027] FIG. 13 is a side view showing a cutting die roll of the
apparatus illustrated in FIG. 12;
[0028] FIG. 14 is a side view showing a heating roll of the
apparatus illustrated in FIG. 1;
[0029] FIG. 15 is a side view showing a heat setting roll of the
apparatus illustrated in FIG. 12; and
[0030] FIG. 16 is an exploded perspective view of a resonant tag
according to yet other embodiment of the present invention.
[0031] FIG. 17 shows a case that a release paper is peeled off from
an adhesion coated on a resonant tag base.
[0032] FIG. 18 shows an example that a non-coated portion on a face
of a resonant tag base on which an adhesion adhesive is coated.
[0033] FIG. 19 shows an example that an adhesion adhesive is coated
in a shape of lattice.
[0034] FIG. 20 is a perspective view of the example of FIG. 18.
[0035] FIG. 21 is a plan view of an embodiment of the
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0036] As a result of extensive and intensive study, the present
inventor has found that a dielectric layer of a desired thickness
can be obtained by a coating process utilizing a liquid resin
instead of the conventional molded resin film and by adhering a
metallic foil circuit using said coated resin (film) as the
adhesive. The present invention has been accomplished based on the
above findings which enable a resonant tag having excellent
resonant frequency characteristics.
[0037] Accordingly, a resonant tag according to the present
invention is characterized in that a circuit-like (coil-like)
metallic foil is adhered to either side or both sides of a
dielectric resin film formed by a coating process.
[0038] The dielectric resin film for use in the present invention
may be formed like a coil in the same shape as that of the
coil-like metallic foil, or it may be a resin film having
approximately the same area and shape defined by the outer
periphery of the coil-like metallic foil.
[0039] More specifically, for example, a resin coating may be
formed first on one side of the metallic foil, and then stamping
out the resin-coated metallic foil into a coil-like shape. In this
manner, a coil-shaped resin film having the same shape as that of
the coil-like metallic foil can be fabricated. Otherwise, the
resonant tag can be fabricated by a process which comprises
preparing a resin film by applying a liquid resin to the surface of
a release paper and the like to form a resin film; adhering a
coil-like metallic foil to the surface of the resulting resin film;
peeling off the release paper from the resin film; and adhering the
coil-like metallic foil at the back side to the resin film on the
side from which the release paper is peeled off. Furthermore, a
resin film can be formed by applying a liquid resin to the surface
of a release paper on which a coil-like metallic foil is
superposed, and further adhering a coil-like metallic foil on the
resin film.
[0040] The liquid resin for use in the present invention in itself
is of liquid, i.e., may be a solvent-free liquid resin such as an
epoxy resin, or a resin solution which is dissolved in a solvent.
Any resin suitable for use in a coating process and having
excellent dielectric properties can be used. Specifically mentioned
are, for instance, polyolefin. Preferably, the resin film thus
obtained functions as an adhesive in adhering a metallic foil to
the resin film. Accordingly, more preferred is a resin of having
thermal adhesion properties. A filler and the like which improves
or increases the dielectric properties of the resulting film can be
incorporated into the resin film.
[0041] The resin film can be formed on either of the sides of the
coil-like metallic foil or on both sides thereof. Moreover, two or
more coil-like metallic foils having a resin film on at least one
side thereof may be superposed and adhered to each other. In such a
case, the metallic foils in each of the layers are connected by a
proper means to obtain the desired resonant frequency
characteristics.
[0042] The resin film for use in the present invention can be
formed by applying the liquid resin over the entire surface by
using roll coating, or by applying to predetermined portions to
provide a coated pattern by means of gravure printing, silk screen
printing, etc. Otherwise, color printing process may be employed to
apply a liquid resin containing a conductive filler such as a
metallic powder and the like to a part of the metallic foil
circuit. The resulting resin film may be used for connecting the
coil-like metallic foil provided on both the surface and the back
of dielectric resin film to form the desired resonant circuit.
Furthermore, the resin film containing the electrically conductive
filler may be utilized to facilitate the destruction of the
resonant circuit.
[0043] Finally, a desired resonant tag can be fabricated by
adhering a support or a decorative sheet such as a paper, a plastic
film, or a plastic sheet by an ordinary method to at least one
surface of the base for the resonant tag obtained by adhering
coil-like metallic foils to the both sides of the resin film to
provide a resonant circuit according to the process described in
the foregoing.
[0044] For instance, a resonant tag can be obtained by adhering a
paper or a plastic film to one side of the base for the resonant
tag obtained above; applying an adhesive to the other side of the
base; and further adhering a release paper to the upper side of the
base having thereon the adhesive. The resulting resonant tag
comprises a release paper so that the resonant tag can be directly
adhered to goods by simply peeling off the release paper.
[0045] In case of conventional resonant tags using a non-adhesive
film such as a polyethylene film as the dielectric, the support has
to be attached to the dielectric using an adhesion adhesive.
However, the resonant tag according to the present invention can be
implemented using an ordinary adhesive, because it uses a resin
film as the dielectric.
[0046] The process according to the present invention for
fabricating a circuit-like metallic foil sheet such as a resonant
tag is characterized in that it uses a laminate comprising a
carrier sheet such as a paper or a plastic film adhered thereto a
metallic foil as the base material, and that it comprises forming,
with notch, a predetermined circuit-like pattern in the metallic
foil of said laminate using a stamping die; disposing the surface
of a support such as a plastic film and the like opposed to the
side of said laminate having thereon the metallic foil; and
transferring the circuit-like metallic foil to the surface of the
support by heating said circuit-like patterned portion from the
carrier sheet side of said laminate or from the support side.
[0047] In the process according to the present invention, the
carrier sheet is adhered to the metallic foil using an easily
removable adhesive so that the metallic foil can be readily peeled
off from the carrier sheet upon transferring the stamped metallic
foil to the surface of the support. In particular, the use of an
adhesive the adhesion force of which decreases when heated is
preferred, because the stamped-out portion alone is transferred to
the support by heating. By thus using the particularly preferred
adhesive of the type above, the adhesion force of the heated
portion can be lowered as compared to that of the unheated
portions, thereby facilitating the pattern transfer of the heated
portion to the support.
[0048] Particularly preferred adhesives satisfying the demand above
include a pressure sensitive adhesive (or adhesion adhesive) into
which a curing agent that accelerates curing upon heating is added.
Also usable in addition to the adhesive above are adhesive
compositions based on a pressure sensitive adhesive and comprising
dispersed therein a thermosetting resin such as an epoxy resin or a
polyamide resin. The adhesion power of the adhesive compositions of
this type decreases upon heating due to the setting of the resin.
Otherwise, adhesive compositions based on an adhesive and
containing further therein an oil and fat or a wax can be used. The
oil and fat or the wax blended with the adhesive precipitates on
the adhesion is separated out on the adhesive face upon heating to
suppress the adhesion force of the adhesive.
[0049] In general, a thermal adhesive resin film is provided to the
surface of the metal foil of the laminate composed of a carrier
sheet and a metallic foil so that the stamped metallic foil can be
transferred to the support in the later process steps by thus
providing the adhesive to the surface thereof. However, this step
can be omitted in case a thermal adhesive resin film or a film
surface-coated with a thermal adhesive resin is used for the
support itself.
[0050] The carrier sheet to be used in the present invention should
be sufficiently thick so that it may not be simultaneously stamped
out when the metallic foil is stamped out into a predetermined
circuit-like pattern by stamping. It should be of a proper
thickness, however, so that the metallic foil adhered thereto would
not break in case the rolled laminate is unrolled for the
continuous processing thereof. Usable as the carrier sheets include
a sufficiently thick and strong paper such as fine paper (slick
paper) or parchment paper, and a plastic film such as a
polyethylene film, polypropylene film, or a polyester film. Among
them, paper is preferred from the viewpoint of, for example, heat
transfer properties upon hot image transfer, ease in handling, and
cost.
[0051] The metallic foil for use in the present invention is not
particularly limited, and usable are, for example, a copper foil,
an aluminum foil, or a stainless steel foil. Moreover, a thin soft
aluminum foil, a foil conventionally believed unsuitable for this
type of application, can be used advantageously in the present
invention. Metallic foils from several microns (.mu.m) to several
hundred microns (.mu.m) can be used in the present invention. More
specifically, however, a foil from 3 to 150 .mu.m in thickness is
preferred. In case of aluminum foils, those from 10 to 60 .mu.m in
thickness are preferred.
[0052] Stamping techniques conventionally known in the art of
manufacturing labels and cans can be readily utilized for forming,
with notch, the predetermined circuit-like pattern in the metallic
foil alone, i.e., half-cutting method.
[0053] The laminate of the metallic foil which is stamped out into
the circuit-like pattern by stamping is transferred to the support
first by using a hot mold having a heating protrusion patterned
into approximately the same shape as that of the stamped-out
circuit-like pattern, or by heating and applying pressure to the
surface of the carrier sheet of the laminate using a heat sealer
and the like. Then, when the laminate is peeled off from the
support, the metallic foil stamped out into a circuit-like pattern
remaining on the support by the thermal adhesion, and the
unnecessary portion is removed together with the laminate. Once the
circuit-like metallic foil is transferred to the support, the
adhesion of the metallic foil to the support is preferably assured,
for example, by further heating and applying pressure to the entire
structure if necessary. In case the support is heated after the
metallic foil is transferred, the heating pattern need not be of
the same width as that of the stamped out metallic foil, and, it
may be, for example, narrower than that of the metallic foil.
[0054] In the heating step for transferring the circuit-like
metallic foil to the support, the heat may be applied from the
support side if a thin sheet such as a paper or a plastic film is
used as the support. Otherwise, the heat may be applied from both
sides of the carrier sheet and the support.
[0055] In fabricating a resonant tag by the process according to
the present invention, a dielectric plastic film or a dielectric
resin film is used as the support. The circuit-like metallic foil
is transferred to each of the sides of the dielectric support using
the above process to form a circuit or a capacitor section on both
sides of the support. In this manner, a resonant circuit is
established to provide the base for the resonant tag.
[0056] In case of using a resin film as the support, a resin
coating is prepared by, for example, applying a predetermined
liquid resin to a release paper. The resin film on the release
paper is then used as the support to transfer thereon the
circuit-like metallic foil. The release paper is peeled off
thereafter and another circuit-like metallic foil can thus be
transferred thereafter to the face of the metallic foil applied
resin film in which the peeling-off is done, i.e., the peeled-off
face, to obtain a base for the resonant tag.
[0057] The resins for use as the dielectric plastic film or the
dielectric resin film include those conventionally used in this
field. Specifically mentioned are films or resin paints such as
polyethylene, polypropylene, polystyrene, polyester, etc.
Furthermore, heat-resistant products can be fabricated using
heat-resistant resins such as polyimide for the support.
[0058] Preferably, a hole or a cutting is provided previously to
the support, i.e., the dielectric plastic film or the dielectric
resin film, to connect the metallic foil circuits formed on the
surface and the back of the support or to facilitate the
destruction of the resonant circuit by applying current in case of
need. The hole or the cutting is provided at a position in the
support where the metallic foil on the surface is superposed on the
metallic foil on the back. The electric energy necessary for
deactivating the resonant state can be controlled by adjusting the
position at which the hole or the cutting is provided. Moreover,
the hole or the cutting can be used for connecting the circuits
provided on the upper and the lower sides of a multi-layered
printed circuit board.
[0059] In fabricating a resonant tag, there is no particular
limitation for the thermal adhesive resin to be applied to the
surface of the metallic foil. Accordingly, any type of resin
suitable for coating and having excellent dielectric
characteristics, such as polyolefin, can be used. In addition, a
filler and the like which improves or increases the dielectric
properties of the resulting film can be incorporated into the resin
film if desired. Furthermore, if necessary, a dielectric plastic
film may be laminated onto the surface of the metallic foil in the
laminate, and the dielectric plastic film may be further coated
with a thermal adhesive resin. In this case, the metal foil in the
laminate is stamped out together with the plastic film so that it
may be transferred to the support.
[0060] Otherwise, in the process according to the present
invention, the base for the resonant tag can be fabricated by
subjecting the laminates each having thereon a metal foil stamped
out into the circuit-like pattern to heating under pressure without
using a support. The thermal adhesive resin applied to the surface
of the metallic foils serve as the support. Accordingly, the
laminates are disposed in such a manner that the side having
thereon the metallic foil may face each other, and heat is applied
from the side of the carrier sheets. Similar to the case described
above, a dielectric resin is used as the resin of the thermal
adhesive resin film. It is also possible to provide the thermal
adhesive resin to the metallic foil of the first laminate alone
while applying no resin film to the metallic foil in the second
laminate. Furthermore, a simple thermal adhesive resin film can be
applied to the metallic foil of the first laminate while applying a
dielectric resin film to the metallic foil of the second laminate.
The resulting two laminates are then joined to provide a base for
the resonant tag as an integrated body.
[0061] The base for the resonant tag thus obtained by adhering
coil-like metallic foils as the resonant circuit to the both
surfaces of the resin film can be finished into a desired product.
A desired resonant tag or a resonant label can be implemented by
adhering a reinforcing member or a decorative sheet such as a
paper, a plastic film, or a sheet to at least one side of the
resulting base for the resonant tag.
[0062] For instance, a paper or a plastic film may be adhered to
one side of the base for the resonant tag using an adhesive, while
applying an adhesion adhesive to the other side and attaching
thereto a release paper. A resonant tag directly applicable to
goods by peeling off the release paper can be obtained in this
manner.
[0063] Thus, because a coating process of a liquid resin is
employed for fabricating a dielectric film is employed, the present
invention provides a resonant tag comprising a dielectric film far
superior to the conventional plastic films fabricated by extrusion
molding concerning tolerance in film thickness. Furthermore, by
using the resin film directly as an adhesive, the fluctuation in
thickness of the dielectric layer in conventional resonant tags
attributed to the plastic film being adhered using an adhesive can
be eliminated. Moreover, a wider selection for a resin is allowed,
and a filler and the like for improving the dielectric
characteristics of the resin film can be added in the resin at a
desired concentration. It is also possible to blend two or more
types of resins as desired. Accordingly, a resonant tag improved in
resonant frequency characteristics or a resonant tag having the
desired flexibility is made available.
[0064] Furthermore, the operation of stamping out the metallic foil
into a coil-like shape in the present invention is also
facilitated, because the resin film is formed on at least one side
of the metallic foil.
[0065] Moreover, the process according to the present invention
comprises using a laminate as a base material comprising a carrier
sheet having adhered thereon a metallic foil, so that the metallic
foil alone can be stamped out into a desired pattern, and that the
stamped-out portion can be transferred to the support by heating
and applying pressure from the carrier sheet side or the support
side. Comparing with the conventional process of die stamping, it
can be seen that the process according to the present invention
allows a desired circuit pattern to be formed even on a thin and
soft metallic foil. The process according to the present invention
furthermore enables the formation of concentric patterns composed
of large and small circles in addition to the continuous coil-like
patterns generally used in the prior art processes.
[0066] In case of using a paper for the carrier sheet, a mark for
aligning the carrier sheets may be formed. By using this mark, the
metallic foil circuits can be formed easily on both the surface and
the back of the support in a superposed arrangement. Thus, a
resonant tag comprising a capacitor consisting of a dielectric film
interposed between two facing metallic foil circuits can be readily
implemented.
[0067] In case a laminate comprising a metallic foil surface-coated
with a thermal adhesive resin film is used as the dielectric layer
in the present invention, the dielectric layer is established by
the coating of a liquid resin. Thus, the resulting dielectric film
is far superior to the conventional plastic films fabricated by
extrusion molding concerning tolerance in film thickness.
Accordingly, a resonance tag improved in resonant frequency
characteristics and in flexibility is made available.
EXAMPLE 1
[0068] FIG. 1 shows an exploded perspective view of a resonant tag
according to an embodiment of the present invention, in which a
resin film 2 being provided as a dielectric layer is formed in the
same shape as that of an aluminum foil 3a stamped out into a
coil-like shape. Referring to FIG. 1, the resin film 2 is disposed
far apart from the aluminum foil 3a. However, in practice, a liquid
resin is applied to the aluminum foil and stamped together with the
aluminum foil 3a. Accordingly, the resin film 2 is integrated with
the surface of the aluminum foil 3a to provide a monolithic
body.
[0069] Referring to FIG. 1, a coil-like aluminum foil 3b is
superposed on the aluminum foil 3a and adhered to the resin film 2
in such a manner that the coiling direction thereof is reversed
with respect to the coiling direction of the aluminum foil 3a. In
case a thermal resin is used for the resin film 2, the aluminum
foil 3a is superposed on the aluminum foil 3b, or a support 4 is
further optionally superposed thereon, and the resulting laminate
is subjected to hot contact bonding. Specifically in the present
example, a resin film 2 is also formed to the aluminum foil 3b in
the same manner as in aluminum foil 3a, and a support 4, e.g., a
paper or a plastic film, is laminated on the lower surface thereof.
A release paper 6 is adhered to the support 4 by interposing an
adhesion adhesive 5 therebetween. On the other hand, a paper 8 is
adhered to the upper surface of the aluminum foil 3a using an
adhesion adhesive or an adhesive 7 to obtain the desired resonant
tag 1.
[0070] The paper 8 is provided to protect or to hide the resonant
circuit thereunder. Accordingly, the paper is provided with a
printing as a label indicating, for instance, a trade name, a
distributor, or an advertising phrase.
[0071] FIG. 2 shows an exploded perspective view of a resonant tag
according to another embodiment of the present invention, in which
a resin film 2a is provided at the same area as that of a shape
defined by the outer periphery of the coil-like aluminum foil 3a.
The other constitution of the resonant tag is the same as that of a
structure illustrated in FIG. 1. Accordingly, the explanation for
the same members as those illustrated in FIG. 1 is omitted by
attaching the same symbols thereto. In the present example, the
resin film 2a is shown as a planar film. However, a liquid resin
may be applied to the entire surface of the coil-like aluminum foil
to form a film. Accordingly, a shape comprising a resin film
between the aluminum foil coils can be implemented. More
specifically, a coil-like protrusion can be formed on a flat plane.
In this manner, the insulation of the aluminum foils formed on both
the surface and the back of the resin film can be further
assured.
[0072] FIG. 3 shows an exploded perspective view of a resonant tag
according to a still other embodiment of the present invention, in
which a coil-like resin film 2 is provided together with a planar
resin film 2a. In case a plastic film 4 is used as the support, a
coil-like aluminum foil 3b having the coil-like resin film 2
provided on one side thereof is adhered first to the plastic film
using the resin film 2. Then, a resin film 2a can be formed by
applying a liquid resin to the entire surface (inclusive of the
surface of the support 4 which is seen through the coil) of the
aluminum foil 3b having no resin film 2 thereon.
[0073] FIG. 4 shows a perspective view of a resonant tag according
to a yet other embodiment of the present invention, in which an
electrically conductive or a semiconductive resin film 2b mixed
therein an electrically conductive material (e.g., an aluminum
powder or a copper powder) is formed in the midway of the resin
film 2 by means of color printing. The conductive resin film is
provided in the midway of the aluminum foil circuit in this
example, however, a conductive resin film can be provided linearly
in the outermost portion 2c of the coil as a connection point to
provide a current path between the metallic foils laminated on the
surface and the back of the resin film 2.
[0074] FIG. 5 is an exploded perspective view of a resonant tag
according to an embodiment of the present invention, in which a
plurality of coil-like aluminum foils each having thereon a resin
film are laminated. More specifically in the present example, three
aluminum foils 3 are laminated. In FIG. 5, a reference numeral 10
shows a position at which the upper and the lower aluminum foils
are connected. A further compact resonant tag having a
predetermined resonant characteristics can be implemented by thus
joining a plurality of foils.
EXAMPLE 2
[0075] FIGS. 7A to 7G are a schematically drawn diagram showing the
cross-sectional view of the step sequential members obtained during
the fabrication process of a resonant tag, which is provided as an
explanatory means for a process according to an embodiment of the
present invention. In FIG. 7A, a metallic foil 102 surface-coated
with a thermal adhesive resin film 101 is adhered to a carrier
sheet 104 using a pressure-sensitive adhesive or an adhesion
adhesive 103 to provide a laminate as the base for the resonant
tag.
[0076] Referring to FIG. 7B, the laminate 110 is subjected to
stamping to form a notch 109 to the metallic foil 102. The
resulting laminate 110 is then superposed on a support (a plastic
film) 108 and the notched portion is heat-contacted by using a mold
111 (FIG. 7C). Upon peeling off the laminate 110, the metallic foil
102 of the heated circuit pattern alone is transferred to the
support 108 (FIG. 7D). After thus providing a circuit-like metallic
foil 102 on the surface of the support 108, the same operation is
repeated to the back thereof to establish a circuit-like metallic
foil 102 on both surfaces of the support 108. Thus is obtained a
base for the resonant tag (FIGS. 7E to 7G).
[0077] FIG. 8 is a perspective view of a fabrication apparatus for
use in the continuous operation of the process described above.
[0078] Referring to FIG. 8, a laminate 150 supplied in the form of
a roll is rewound and fed to a first cutting press 160 for stamping
out the metallic foil. The metallic foil is stamped out together
with a support 151 so that it may be transferred to the support 151
by using the first heating press 161. The combined laminate 150 and
the support 151 is separated at the reverse roll 167. The
unnecessary laminate 152 is taken up, while a support 151a having
thereon the metallic foil circuit is further subjected to pressing
under heat by using a first heat setting press 162.
[0079] The first cutting press 160 for use in stamping out the
metallic foil and the portion for transferring the metallic foil to
the support 151 using the first heating press 161 are illustrated
in FIG. 9. Referring to FIG. 9, there is also shown a perforating
apparatus 190 for boring a hole (reference can be made to FIG. 16)
in the support 151 (in a case that the support is a dielectric
film) for use in connecting the metallic foil circuit on the
surface of the dielectric film with that on the back of the
film.
[0080] Turning to FIG. 8, the support 151a provided with a metallic
foil circuit over one surface thereof is then reversed by the
reverse roll 168. The back of the support 151a is combined to a
laminate 150 which is rewound from a rolled laminate 150 shown in
the right hand side of FIG. 8, and is transferred with a metallic
foil in the same manner as described above using a second cutting
press 163. In this manner, the support 151a together with the
laminate 150 is passed through a second heating press 164 and a
second heat setting press 165 to provide a final product 153 having
a metallic foil circuit on the surface and the back of the support
151a.
[0081] If necessary, a printed paper is attached, an adhesion
adhesive is applied, or a release paper is laminated to the product
thus obtained to obtain a resonant tag or a resonant label.
EXAMPLE 3
[0082] FIGS. 10A to 10G are a schematically drawn flow diagram
showing the cross section views of the step sequential members
obtained during the fabrication process of a resonant tag, which is
provided as an explanatory means for a process according to another
embodiment of the present invention. The process steps illustrated
in FIGS. 10A to 10D are the same as those described in Example 2
with reference to FIGS. 7A to 7D. A circuit-like metallic foil 102
is provided on one side of the support 107, and a laminate 110
having provided previously thereon a metallic foil 102 by stamping
is superposed on the upper side of the metallic foil 102 provided
on the support 107. The entire structure is then subjected to
heating under pressure to form another circuit-like metallic foil
102 on the surface of the previously established circuit-like
metallic foil 102.
[0083] The support 107 of the base for a resonant label thus
obtained is coated with a pressure sensitive adhesive (adhesion
adhesive) 106 for use in adhering the resonant label, and a release
paper 105 is attached to the surface covered on the
adhesion-adhesive coated label to finally obtain a resonant
label.
[0084] FIG. 11 is a perspective view of a fabrication apparatus for
use in the continuous operation of the process described above.
[0085] Similar to the process described in Example 2 with reference
to FIG. 8, a laminate 150 supplied in the form of a roll is rewound
and fed to a first cutting press 160 for stamping out the metallic
foil. The metallic foil is stamped out together with a support 151
so that it may be transferred to the support 151 by using the first
heating press 161. The combined laminate 150 and support 151 are
separated at the reverse roll 167. The unnecessary laminate 152 is
taken up, while the support 151a having thereon the metallic foil
circuit is further subjected to pressing under heating by using a
first heat setting press 162. The process of the present example
is, however, different from that with reference to FIG. 8. More
specifically, the support 151a having the metallic foil circuit on
one face thereof is fed to the next step without being reversed by
the roll 168. The support 151a is assembled with a laminate 150
rewound from the rolled laminate 150 placed on the center of the
apparatus. The laminate 150 has thereon a stamped metallic foil
provided in the same manner as that in Example 2 using a second
cutting press 163. The resulting structure comprising the support
151a and the laminate 150 is passed through a second heating press
164 and the second heat setting press 165 to finally obtain a
product 154 having a second metallic foil circuit on the metallic
foil circuit previously provided on the support. A resonance label
as illustrated in FIG. 10G is finally obtained by applying an
adhesion adhesive to the support of the product obtained above, and
further adhering thereto a release paper.
EXAMPLE 4
[0086] FIG. 12 shows another type of a fabrication apparatus for
use in the continuous operation of the process according to the
present invention. The apparatus differs from those described in
the foregoing examples in that rolls are used in the place of plate
type cutting press, heating press, and heat setting press.
[0087] Referring to FIG. 12, the apparatus comprises a first and
second cutting die rolls 180 and 183, heating rolls 181 and 184,
and heat setting rolls 182 and 185.
[0088] Referring to FIG. 13, the cutting die rolls 180 for use in
the present apparatus may be a pair of rolls comprising, for
instance, a metallic roll 180a equipped with a cutting blade 801 on
the surface thereof and a rubber roll 180b having a smooth surface.
Referring to FIG. 14, the heat setting rolls 181 may be, for
example, a pair of rolls 181a and 181b each having a heating
pattern protrusions on the surface thereof in a manner similar to
the relief printing rolls. Referring to FIG. 15, for instance, the
pair of heat setting rolls 182 comprise two rolls each having a
smooth surface.
[0089] The apparatus illustrated in FIG. 12 is essentially the same
as that shown in FIG. 11, except that the presses are replaced by
rolls.
EXAMPLE 5
[0090] FIG. 16 shows an exploded perspective view of a modified
type of a resonant tag obtained by a process described in Example
2. A hole 113 is provided previously to a plastic dielectric film
112 that is used as the support, and circuits are provided on both
sides of the dielectric film 112 using a metallic foil 102. The
hole 113 perforated in the dielectric film 112 is used for
connecting the circuits provided on both sides of the dielectric
film 112, or for destroying the resonant circuit.
[0091] In the resonant tag according to the present example, a
non-coated portion can be left over on the thermal adhesive resin
film 101 formed on the surface of the metallic foil 102 of the
laminate at the position corresponding to the hole 113 provided to
the dielectric film 112.
[0092] Referring to FIG. 16, the resonant tag does not have a
capacitor electrode section on the edges of the coil-like circuit.
More specifically, coil-like metallic foil circuits 102 are formed
on both sides of the dielectric film 112 so that the circuits
themselves function as the capacitor electrode plates. That is, the
circuits are disposed faced to each other with a dielectric film
interposed therebetween. The electric energy and the like necessary
for destroying the resonant circuit can be controlled by adjusting
the position of the hole 113.
[0093] The present invention has been described in detail by making
special reference to resonant tags and resonant labels. However,
the present invention enables transfer of linearly pattenred
metallic foils of a desired width (e.g., from 1 mm to about 10 mm)
to various types of articles. Accordingly, the application field of
the present invention is not only limited to that of resonant tags,
single layer printed circuit boards, multi-layered printed circuit
boards, etc. Other application fields include the production of
electric carpets, electric blankets, heating plates for melting
snow, etc., in which the present invention is applied to
heat-resistant plastic sheets and woven cloth; defoggers for
automobiles, in which the present invention is applied to glass
sheets; and defrosting glasses and sheets, in which the present
invention is applied to glass sheets and vinyl sheets of
greenhouses. It is also useful in extensive fields, inclusive of
the field of manufacturing ceramic bodies such as chinawares or
japan, in which metallic patterns are formed.
[0094] While the invention has been described in detail and with
reference to specific embodiments thereof, it will be apparent to
one skilled in the art that various changes and modifications can
be made therein without departing from the spirit and scope
thereof.
[0095] In a resonant label of such a type that an adhision adhesive
5 is coated on one-side face of a resonant tag base A and a release
paper 6 is covered thereon, there is a case that static electricity
is generated when the release paper 6 is peeled off from the face
of the adhision adhesive 5 in use of the final product. (see FIG.
17) At that time, there is possibility that resonant
characteristics are lost (or diactivated) by the electrostatic
discharge.
[0096] In order to prevent such a defect, it may select an adhesion
adhesive which does not cause static electricity or provide
non-coated portions 5a on the face of the resonant tag material on
which the adhesion adhesive is coated, as shown in FIGS. 18 to 20.
FIG. 28 shows an example that the non-coated portions 5a are
linearly provided. FIG. 20 shows a perspective view of the example
of FIG. 18. The linear-shaped non-coated portions 5a may be
provided in parallel to a direction where the release paper 6 is
peeled off or may be provided at a right angle thereto. FIG. 19
shows an example that the non-coated portion 5a is provided in a
shape of a lattice. On top of these examples, the adhesion adhesive
may be provided in appropriate intervals, e.g., in a shape of
dotted lines.
[0097] In the conventional resonant tags, a film such as plastic
film has been used as a dielectric layer and coil circuits of
resonant circuits have been formed on the both sides of the
dielectric layer. In a method of transmitting very strong resonant
frequencies to the resonant tags in the conventional method of
diactivating the resonant circuits, the thickness of the dielectric
layer has been thick and has not been easily shorted, so that it
has been relied on oa method that a portion which is easily shorted
is formed at the neighborhood of a capacitor electrode plate
section provided at the end portion of the resonant circuits.
[0098] In the present invention, the dielectric layer is different
from the conventional plastic film and is formed from very thin
resin layer having dielectric characteristics and having several
microns in thickness and which has also a role of an adhesive. In a
case that strong dielectric frequencies are transmitted to the
resonant circuits in the conventional method, a large number of
electrons are accumulated at a portion, e.g., end portion(s) of
bent portion(s) of coil circuits, which is electrically most weak,
and a dielectric layer at that portion is destroyed and
electrically shorted, whereby the circuits which have been arranged
to be constant frequencies can be destroyed. As the electrically
most weak portion, it will not be limilted to the bent portion of
the coil circuit, but it may be prepared by narrowing the width of
the coil circuit or partly narrowing parts of the coil circuit.
[0099] The above-mentioned effects of destroying circuits are
remarkably exerted in a case of a resonant tag in which a capacitor
electrode plate section ois not formed at the end portion of the
resonant circuit and instead, two coil circuits which form a
resonant circuit are opposed to each other by sandwiching the
dielectric layer and are plasted to utilize the circuits themselves
as a capacitor electrode plate section.
[0100] Referring now to FIG. 21, which shows an embodiment of the
invention, "A" shows shorting portions of two coils, and "B" shows
the range of the destroyed portion. This range becomes electrically
the most weak portion, but other portions may become exceptionally
electrically weak.
* * * * *