EP0422919A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Antistatic adhesive tape
Assignee: Waterford Research and Development Ltd
•
Filing: 1990-10-10
•
Granted: —
•
Expires: 2010-10-10
Abstract
Abstract An antistatic pressure-sensitive adhesive tape, particularly for use in masking printed circuit boards during wave soldering, comprises 1. a polymeric film support (4) e.g. of polyimide film; 2. an intermediate electrically conductive layer (5, 12) e.g. of polymeric binder (7) containing relatively small electrically conductive filler particles (6), or a metal foil (12); and 3. a layer of pressure-sensitive adhesive (8, 15), the adhesive either containing relatively large electrically-conductive particles (9) which provide conductive pathways from one main face (3) of the adhesive layer to the other (11), or being penetrated by protrusions (14) from the intermediate layer (12) which provide such pathways, the polymeric film support, intermediate layer and adhesive layer all being resistant to temperatures up to 250 o C for up to 5 seconds.
Inventors
- 👤 Lutz R. Weinhold
- 👤 John D. Mcdonough
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 10:07
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/0073; H05K3/0076; C; C09; C09J; C09J7/00; C09J7/20; C09J7/29; C09J2203/00; C09J2203/31; C09J2301/00; C09J2301/10; C09J2301/16; C09J2301/162; H05K2201/00; H05K2201/02; H05K2201/0203; H05K2201/0206; H05K2201/0215; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0355; H05K2201/0364; H05K2201/0382; H05K2203/00; H05K2203/01; H05K2203/0191; H05K2203/06; H05K2203/068; H05K3/30; H05K3/32; H05K3/34; H05K3/3452; H05K3/3465; H05K3/3468
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
80 words
An antistatic pressure-sensitive adhesive tape comprising 1) a polymeric film support (4); 2) an intermediate electrically-conductive layer (5, 12); and 3) a layer of pressure-sensitive adhesive (8, 15); wherein electrically conductive pathways (9, 14) are provided from the outer surface (3) of the pressure-sensitive adhesive layer (9, 14) to the intermediate layer (5), and wherein the polymeric film support, intermediate layer and pressure-sensitive adhesive layer are all resistant to temperatures up to 250 o C for up to 5 seconds.
Claim 2
Dependent Claim
80 words
An antistatic pressure-sensitive adhesive tape comprising 1) a polymeric film support (4); 2) an intermediate electrically-conductive layer (5, 12); and 3) a layer of pressure-sensitive adhesive (8, 15); wherein electrically conductive pathways (9, 14) are provided from the outer surface (3) of the pressure-sensitive adhesive layer (9, 14) to the intermediate layer (5), and wherein the polymeric film support, intermediate layer and pressure-sensitive adhesive layer are all resistant to temperatures up to 250 o C for up to 5 seconds.
Claim 3
Dependent Claim
30 words
A tape according to Claim 1 wherein the support, intermediate layer and pressure-sensitive adhesive layer are all resistant to temperatures up to 260 o C for up to 25 seconds.
Claim 4
Dependent Claim
61 words
A tape according to either of the preceding claims wherein the intermediate layer (5) comprises a layer of a polymeric binder (7) containing electrically conductive particles (6) which provide conductive pathways in at least one direction parallel to the main plane of the tape, preferably such that the intermediate layer has a surface electrical resistance not greater than about 10⁵ ohms/cm.
Claim 5
Dependent Claim
39 words
A tape according to Claim 3 wherein the intermediate layer contains 30-80% by weight of conductive filler, based on the total solids of the intermediate layer, the filler preferably having an average particle size in the range 1-5 micrometres.
Claim 6
Dependent Claim
67 words
A tape according to any of the preceding claims wherein the intermediate layer comprises a layer of a polymeric binder selected from silicones and copolymers thereof such as silicone-polyester copolymers or fluorosilicones, polyimides, epoxy resins and poly(ethylene vinyl acetate) and an electrically conductive filler selected from graphite powder, carbon black powder, nickel, aluminium, copper, bronze, silver and gold powders, and particles coated with any of the foregoing.
Claim 7
Dependent Claim
33 words
A tape according to Claim 1 or 2 wherein the intermediate layer comprises a metal coating preferably of aluminium applied to the polymeric film support by metallisation or as a laminated metal foil.
Claim 8
Dependent Claim
47 words
A tape according to any of the preceding Claims wherein the pressure-sensitive adhesive layer (8) is in contact with the intermediate layer and the adhesive contains electrically conductive particles (9) which provide conductive pathways from one main face (3) of the adhesive layer to the other (11).
Claim 9
Dependent Claim
30 words
A tape according to Claim 7 wherein the pressure-sensitive adhesive layer contains 5-30% by weight of conductive filler (9), preferably having an average particle size in the range 20-50 micrometres.
Claim 10
Dependent Claim
38 words
A tape according to Claim 8 wherein the ratio between the average particle size of the filler in the adhesive layer and the thickness of the adhesive layer is in the range 1:2 to 2:1, preferably about 1:1.
Claim 11
Dependent Claim
19 words
A tape according to any of the preceding claims wherein the pressure-sensitive adhesive layer comprises a polysiloxane resin/gum adhesive.
Claim 12
Dependent Claim
32 words
A tape according to Claim 7 wherein the conductive filler is selected from metal powders including nickel, copper or aluminium, bronze powder, silver powder, gold powder, graphite powder or carbon black powder.
Claim 13
Dependent Claim
44 words
A tape according to any of Claims 1-6 wherein the intermediate electrically-conductive layer (12) has protrusions (14) which extend through the pressure-sensitive adhesive layer (15) and which provide the conductive pathways from the outer surface (3) of the adhesive layer to the intermediate layer.
Claim 14
Dependent Claim
23 words
A tape according to Claim 12 wherein the intermediate layer comprises a metal foil (12) which has been embossed to produce such protrusions.
Claim 15
Dependent Claim
31 words
A tape according to Claim 13 wherein the embossed metal foil coated with the pressure-sensitive adhesive is laminated to the polymeric film support by means of a heat-resistant laminating adhesive (13).
Claim 16
Dependent Claim
85 words
An antistatic pressure-sensitive adhesive tape comprising: 1) a polymeric film support (4); 2) an intermediate electrically conductive coating (5) on the support, and 3) a layer of pressure-sensitive adhesive (8) in contact with the intermediate electrically-conductive coating (5), the adhesive containing electrically-conductive particles (9) which provide conductive pathways from one main face (3) of the adhesive layer to the other (11), the polymeric film support, intermediate coating and adhesive layer all being resistant to temperatures up to 250 o C for up to 5 seconds.
Claim 17
Dependent Claim
85 words
An antistatic pressure-sensitive adhesive tape comprising: 1) a polymeric film support (4); 2) an intermediate electrically conductive coating (5) on the support, and 3) a layer of pressure-sensitive adhesive (8) in contact with the intermediate electrically-conductive coating (5), the adhesive containing electrically-conductive particles (9) which provide conductive pathways from one main face (3) of the adhesive layer to the other (11), the polymeric film support, intermediate coating and adhesive layer all being resistant to temperatures up to 250 o C for up to 5 seconds.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.