US4707435A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Industrial X-ray system
Assignee: 3M Co
•
Filing: 1983-04-13
•
Granted: 1987-11-17
•
Expires: 2003-04-13
Abstract
Abstract Industrial radiographic systems having low grainines and high information density may be constructed with intensifying screens sandwiching radiation sensitive elements having emulsions wherein the average size of the silver halide grains is less than 0.4 micrometers.
Inventors
- 👤 Thomas D. Lyons
- 👤 Peter B. Jamieson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:26
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/16; Y; Y10; Y10S; Y10S430/00; Y10S430/167
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
151 words
An industrial radiographic system comprising two high energy particle radiation intensifying screens sandwiching a radiation sensitive element which comprises: (1) a base, (2) a decolorizable dye underlayer on at least one side of the base, (3) a first black-and-white silver halide emulsion layer over said dye underlayer, and (4) a second black-and-white silver halide emulsion layer on the other side of said base, wherein both of said silver halide emulsion layers are spectrally sensitized to the wavelength of radiation emitted by said screens when struck by high energy particle radiation and wherein the average size of the silver halide grains in the emulsions are below 0.4 micrometers, at least 75% of the total number of grains are within 0.07 micrometers of the average grain size, both emulsions provide a contrast of greater than 4.0 at an optical density of 2.0, and the element can provide D max of at least 3.5.
Claim 2
Dependent Claim
151 words
An industrial radiographic system comprising two high energy particle radiation intensifying screens sandwiching a radiation sensitive element which comprises: (1) a base, (2) a decolorizable dye underlayer on at least one side of the base, (3) a first black-and-white silver halide emulsion layer over said dye underlayer, and (4) a second black-and-white silver halide emulsion layer on the other side of said base, wherein both of said silver halide emulsion layers are spectrally sensitized to the wavelength of radiation emitted by said screens when struck by high energy particle radiation and wherein the average size of the silver halide grains in the emulsions are below 0.4 micrometers, at least 75% of the total number of grains are within 0.07 micrometers of the average grain size, both emulsions provide a contrast of greater than 4.0 at an optical density of 2.0, and the element can provide D max of at least 3.5.
Claim 3
Dependent Claim
12 words
The system of claim 1 wherein said screens are X-ray intensifying screens.
Claim 4
Dependent Claim
16 words
The system of claim 2 wherein the average grain size is between 0.075 and 0.35 micrometers.
Claim 5
Dependent Claim
37 words
The system of claim 2 wherein the emulsions are sensitized by at least one sensitizing dye so that the maximum sensitivity of the emulsions is within 50 nanometers of the maximum intensity wavelength emission of the screens.
Claim 6
Dependent Claim
22 words
The system of claim 4 wherein said maximum sensitivity is within 25 nanometers of the maximum intensity wavelength emission of the screens.
Claim 7
Dependent Claim
64 words
A process for the non-destructive testing of industrial materials which comprises placing an industrial material between a controlled X-ray source and the radiographic system of claim 2, directing X-rays from the source through the industrial material and into said radiographic system at an angle approximately perpendicular to said intensifying screens to generate a latent image in said first and second silver halide imaging layers.
Claim 8
Dependent Claim
25 words
The system of claim 2 wherein the phosphors of said screens comprise gadolinium oxysulfides, lathanum oxysulfides, gadolinium-lanthanum oxysulfides, gadolinium oxybromides, lanthanum oxybromides, or lanthanum-gadolinium oxybromides.
Claim 9
Dependent Claim
37 words
The system of claim 3 wherein the emulsions are sensitized by at least one sensitizing dye so that the maximum sensitivity of the emulsions is within 50 nanometers of the maximum intensity wavelength emission of the screens.
Claim 10
Dependent Claim
25 words
The system of claim 3 wherein the phosphors of said screens comprise gadolinium oxysulfides, lathanum oxysulfides, gadolinium-lanthanum oxysulfides, gadolinium oxybromides, lanthanum oxybromides, or lanthanum-gadolinium oxybromides.
References Cited (Backward Citations)
DE232661C
Cited
US3753714A
Cited
US3705858A
Cited
US3725704A
Cited
US4130428A
Cited
US4130429A
Cited
US3912933A
Cited
US3922545A
Cited
US4049454A
Cited
GB1565811A
Cited
US4177071A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-11-16 | 1991-05-18 | 1991-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-16 | 1995-05-18 | 1995-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-16 | 1999-05-18 | 1999-11-17 | $7700.00 | Window Closed / Lapsed |