US3612871A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for making visible radiation damage tracks in track registration materials
Assignee: General Electric Co
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Filing: 1969-04-01
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Granted: 1971-10-12
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Expires: 1989-04-01
Abstract
Abstract An improved method for treating a plastic film by charged particle irradiation to make tracks formed in the film visible. The film is subjected to irradiation with charged particles, then is exposed to radiation selected from the group consisting of electromagnetic radiation having wavelengths less than about 4,000 angstroms and electrons having energy levels above about 1.5 X 106 electron volts in the presence of oxygen. When treated with a solvent which preferentially attacks the material along the particle tracks, the tracks dissolve away rapidly, leaving substantially cylindrical holes in the film, with little degradation of the body of the film. This preetching treatment results in more rapid etching of the damage tracks, in tracks of more uniform cross section, in smaller initial pore sizes and in greater thermal stability of the tracks.
Inventors
- 👤 Wayne T Crawford
- 👤 James S Humphrey Jr
- 👤 Warren De Sorbo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 05:13
CPC Classifications
G; G01; G01T; G01T5/00; G01T5/10
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
90 words
In a track registration process wherein a track registration material is irradiated with charged particles which form tracks of altered material along their trajectories in the material and the irradiated material is etched with a reagent which selectively attacks and enlarges the altered material along said tracks whereby said tracks are made visible; the improvement wherein said irradiated material is exposed to radiation selected from the group consisting of electromagnetic radiation having wavelengths less than about 4,000 angstroms and electrons having energy levels above about 1.5 X 106 electron volts.
Claim 2
Dependent Claim
90 words
In a track registration process wherein a track registration material is irradiated with charged particles which form tracks of altered material along their trajectories in the material and the irradiated material is etched with a reagent which selectively attacks and enlarges the altered material along said tracks whereby said tracks are made visible; the improvement wherein said irradiated material is exposed to radiation selected from the group consisting of electromagnetic radiation having wavelengths less than about 4,000 angstroms and electrons having energy levels above about 1.5 X 106 electron volts.
Claim 3
Dependent Claim
21 words
The process according to claim 1 wherein said charged particles are alpha particles and said track registration material comprises cellulose materials.
Claim 4
Dependent Claim
22 words
The process according to claim 1 wherein said charged particles are fission fragments and said track registration material comprises a polycarbonate resin.
Claim 5
Dependent Claim
13 words
The process according to claim 1 wherein said electromagnetic radiation is ultraviolet radiation.
Claim 6
Dependent Claim
22 words
The process according to claim 4 wherein said ultraviolet radiation has wavelengths in the region from about 3,600 to about 3,800 angstroms.
Claim 7
Dependent Claim
13 words
The process according to claim 1 wherein said electromagnetic radiation is gamma radiation.
Claim 8
Dependent Claim
12 words
The process according to claim 1 wherein said electromagnetic radiation is X-radiation.
Claim 9
Dependent Claim
15 words
The process according to claim 1 wherein said electromagnetic radiation results from electron beam irradiation.
Claim 10
Dependent Claim
63 words
A track registration process comprising the steps of irradiating a track registration material with charged particles which form damage tracks along paths in said material traversed by said charged particles; exposing the irradiated material to radiation selected from the group consisting of electromagnetic radiation having wavelengths less than about 4,000 angstroms and electrons having energy levels above about 1.5 X 106 electron volts.
Claim 11
Dependent Claim
63 words
A track registration process comprising the steps of irradiating a track registration material with charged particles which form damage tracks along paths in said material traversed by said charged particles; exposing the irradiated material to radiation selected from the group consisting of electromagnetic radiation having wavelengths less than about 4,000 angstroms and electrons having energy levels above about 1.5 X 106 electron volts.
Claim 12
Dependent Claim
21 words
The process according to claim 9 wherein said charged particles are alpha particles and said track registration material comprises cellulose materials.
Claim 13
Dependent Claim
22 words
The process according to claim 9 wherein said charged particles are fission fragments and said track registration material comprises a polycarbonate resin.
Claim 14
Dependent Claim
38 words
The process according to claim 11 wherein said material is immersed in an etching solution comprising about 6-normal sodium hydroxide at a temperature of from about 50* C. to about 80* C. for about 5 to 20 minutes.
Claim 15
Dependent Claim
13 words
The process according to claim 9 wherein said electromagnetic radiation is ultraviolet radiation.
Claim 16
Dependent Claim
22 words
The process according to claim 13 wherein said ultraviolet radiation has wavelengths in the region from about 3,600 to about 3,800 angstroms.
Claim 17
Dependent Claim
13 words
The process according to claim 9 wherein said electromagnetic radiation is gamma radiation.
Claim 18
Dependent Claim
12 words
The process according to claim 9 wherein said electromagnetic radiation is X-radiation.
Claim 19
Dependent Claim
15 words
The process according to claim 9 wherein said electromagnetic radiation results from electron beam irradiation.
References Cited (Backward Citations)
US3493751A
Cited
US3415993A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-11 | 1975-04-12 | 1975-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-11 | 1979-04-12 | 1979-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-11 | 1983-04-12 | 1983-10-12 | $7700.00 | Window Closed / Lapsed |