Stock material or miscellaneous articles – Web or sheet containing structurally defined element or... – Adhesive outermost layer
Reexamination Certificate
1999-02-22
2001-05-22
Zirker, Daniel (Department: 1771)
Stock material or miscellaneous articles
Web or sheet containing structurally defined element or...
Adhesive outermost layer
C428S343000, C428S354000, C428S458000, C428S461000, C428S480000
Reexamination Certificate
active
06235385
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electrically conductive adhesive tape formed by depositing a conductive metal layer over one surface of a resin film.
2. Description of the Prior Art
Electrically conductive adhesive tapes are widely used in a variety of technical fields associated with electrical and electronic products to bond or fix an element to a support while maintaining an electrical conductibility between the element and support.
For example, such conductive adhesive tapes are widely used in assembling processes for video display appliances such as televisions. Where such conductive adhesive tapes are used in an assembling process for a television, they serve to fix the Braun tube of the television while grounding electrostatic charges and electromagnetic waves accumulatively induced on the outer peripheral surface of the Braun tube, thereby removing the electrostatic charges and electromagnetic waves. Such conductive adhesive tapes are also widely used in assembling processes for cars and electronic products.
Generally, a Braun tube is comprised of an evacuated bulb made of glass, so that it is likely to be damaged in the event of an external impact. For this reason, such a Braun tube is not directly fixed to a casing or housing, but fixed to the casing or housing by means of a bracket bonded to the outer peripheral surface of the Braun tube by means of an adhesive tape.
Since the adhesive tape used to bond the bracket to the Braun tube has a buffering function, it is possible to prevent the Braun tube from being damaged. Even though the Braun tube explodes as it is broken in the event of a severe external impact or other accident, it is possible to reduce the flying range of pieces of broken glass, by virtue of the adhesive tape.
For such an adhesive tape adapted to fix a bracket to a Braun tube, an electrically conductive tape is mainly used in order to additionally prevent electrostatic charges and electromagnetic waves induced on the outer peripheral surface of the Braun tube from being outwardly emitted.
In a Braun tube used in video display appliances such as televisions, a very high voltage is applied to the inner surface of the Braun tube so as to form an image on that inner surface. Due to the application of such a very high voltage, electrostatic charges are induced on the outer peripheral surface of the Braun tube. When such electrostatic charge is accumulated as no removal thereof is carried out, a magnetic field and an electric field are generated. As a result, electromagnetic waves are outwardly emitted.
Recent expansion of the application of such a Braun tube results in an increase in the possibility that the user may touch or otherwise come into contact with the Braun tube. However, electromagnetic waves emitted from the Braun tube are harmful to people. Electrostatic charges induced on the Braun tube adversely influence the functions of the Braun tube. When the user is in contact with electrostatic charges for an extended period of time, he may experience unpleasant effects. In severe cases, such electrostatic charges may cause various diseases. A disturbance phenomenon may occur in electronic circuits included in the television, due to the electrostatic charges induced on the Braun tube. In severe cases, an image jittering phenomenon may occur.
In order to prevent an accumulation of electrostatic charges induced on the Braun tube and to shield electromagnetic waves emitted from the Braun tube, a variety of methods have been proposed. One method is to use an electrically conductive adhesive tape, as shown in FIG.
1
.
In accordance with the method shown in
FIG. 1
, an elongated, electrically conductive adhesive tape is cut into pieces having a desired length. The conductive adhesive tape pieces are bonded to the outer peripheral surface of a Braun tube while being uniformly spaced from one another. An iron bracket
4
is then bonded to the outer peripheral surface of the Braun tube by means of the conductive adhesive tape pieces while being electrically connected to the conductive adhesive tape pieces. Thus, electrostatic charges induced on the Braun tube is discharged via the bracket to an earth circuit
3
equipped in a cabinet.
Referring to
FIGS. 2 and 4
, an electrically conductive adhesive tapes are illustrated which is typically used for the above mentioned purpose. As shown in
FIGS. 2 and 4
, the conductive adhesive tape includes a conductive metal foil
11
made of copper or aluminum, a conductive adhesive layer
10
formed over the conductive metal foil
11
, and a strippable protective sheet. The conductive adhesive tape is used after stripping the protective sheet therefrom.
As shown in
FIG. 1
, the Braun tube has several sections, namely, a display panel section having a conductive surface on its inner surface to display an image, a neck section accommodating an electron gun
9
, and a funnel section jointing the panel section to the neck section. In order to provide the conductive surface, a conductive layer
2
is formed on the inner surface of the display panel section by sputtering metal or conductive ceramic. A deflection yoke, which serves to stabilize an electron beam emitted from the electron gun
9
, is mounted in the funnel section. A funnel-shaped metal sheet
8
is also mounted around the funnel section in order to shield electromagnetic waves emitted from the funnel section. A desired portion of the remaining outer surface of the Braun tube is attached with a conductive adhesive tape
7
in order to prevent an accumulation of electrostatic charges induced on the Braun tube and an emission of electromagnetic waves from the Braun tube.
In
FIG. 1
, the reference numeral
5
denotes a silicon resin layer adapted to insulate the outer surface of the Braun tube from a high-voltage current flowing from an anode. The reference numeral
6
denotes the anode.
The deflection yoke, which is not shown in
FIG. 1
, is comprised of an electromagnet and adapted to amplify an electron beam emitted from the electron gun
9
while adjusting the advance direction of the electron beam. Where a conductive adhesive tape, which has the structure shown in
FIG. 2
while having a nonferrous metal layer covering the entire upper or lower surface thereof, lines of magnetic force emitted from the deflection yoke can not pass through the nonferrous metal layer. Such lines of magnetic force serve to uniformly spread the electron beam emitted from the electron gun. The nonferrous metal layer shields lines of magnetic force having such a function, thereby resulting in a degradation in picture quality.
The present invention relates to an electrically conductive adhesive tape including a deposited metal layer having a net-shaped structure, as shown in
FIG. 3
c,
thereby being capable of preventing an accumulation of electromagnetic charge and an emission of electromagnetic waves without interfering with the effect provided by lines of magnetic force. In
FIGS. 3
a
to
3
c,
the metal layer is denoted by the reference numeral
13
.
The metal layer
13
may have a structure completely covering the entire upper surface of a resin film, in association with Braun tube sections not being subjected to the influence of lines of magnetic force, namely, having no effect provided by the metal layer.
Conventional conductive tapes are made using a method in which a conductive metal foil, such as an aluminum foil or copper foil, is bonded to a conductive adhesive layer formed by coating a conductive adhesive over a surface of a strippable protective sheet, or a method in which a conductive metal foil coated at one surface thereof with a conductive adhesive layer and subjected to a release process at the other surface thereof is used so that it can be rolled without using any strippable protective sheet.
Here, the term “conductive adhesive” means an adhesive having an adhesive material produced by dissolving an acrylic resin or rubber in an organic solvent, and a certain amount of conductive metal powder added in
Harrison & Egbert
Shin Wha Products Co., Ltd.
Zirker Daniel
LandOfFree
Electrically conductive adhesive tape does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electrically conductive adhesive tape, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electrically conductive adhesive tape will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2451949