EP0065877B1 - Industrielles Röntgenstrahlungssystem - Google Patents

Industrielles Röntgenstrahlungssystem Download PDF

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Publication number
EP0065877B1
EP0065877B1 EP82302617A EP82302617A EP0065877B1 EP 0065877 B1 EP0065877 B1 EP 0065877B1 EP 82302617 A EP82302617 A EP 82302617A EP 82302617 A EP82302617 A EP 82302617A EP 0065877 B1 EP0065877 B1 EP 0065877B1
Authority
EP
European Patent Office
Prior art keywords
screens
silver halide
industrial
emulsions
gadolinium
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP82302617A
Other languages
English (en)
French (fr)
Other versions
EP0065877A1 (de
Inventor
Thomas D. Lyons
Peter B. Jamieson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
3M Co
Original Assignee
Minnesota Mining and Manufacturing Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Minnesota Mining and Manufacturing Co filed Critical Minnesota Mining and Manufacturing Co
Publication of EP0065877A1 publication Critical patent/EP0065877A1/de
Application granted granted Critical
Publication of EP0065877B1 publication Critical patent/EP0065877B1/de
Expired legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
    • G03C5/16—X-ray, infrared, or ultraviolet ray processes

Definitions

  • This invention relates to a novel, high definition, industrial radiographic system.
  • the system uniquely combines fine grain silver halide emulsion photographic film and a light-emitting phosphor screen.
  • Nondestructive testing of articles and materials has become an integral part of quality control in modern manufacturing industries. This type of testing enables on-line and intensive evaluation of the structural soundness of products.
  • One of the most commonly used forms of nondestructive testing is radiographic images taken on industrial materials.
  • Industrial X-rays have been used for many years in the testing of support beams used in the construction of buildings, bridges and the like. They are particularly useful in the evaluation of welds and in testing metal plates for minute flaws which could affect performance.
  • Radiographic emulsions used in industrial screen/film X-ray procedures typically have emulsions where the average grain size is above 0.5 micrometers (e.g., U.S. Patent No. 3,922,545, col. 13, lines 25-46) and generally over 1 micrometer (e.g., U.S. Patent No. 3,753,714, col. 4, lines 34-40).
  • U.S. Patent Nos. 4,177,071 and 4,130,428 discloses a range of 0.25 to 1.2 micrometers for the grain size, butthe examples are only of emulsions having average grain sizes of 0.5, 0.6, 0.7 and 0.8 micrometers.
  • an industrial radiographic system comprising two high energy particle radiation intensifying screens sandwiching a radiation sensitive element which comprises: a base, a decolorizable dye underlayer on at least one side of the base, a first silver halide emulsion layer over said dye underlayer, and a second 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 characterized in that the average size of the silver halide grains in the emulsions are between 0.05 and 0.4 micrometers.
  • the screens may be X-ray intensifying screens.
  • the average size is between 0.075 and 0.35 micrometers and most preferably between 0.10 and 0.25 or even 0.20 micrometers.
  • the silver halide grains must be sensitized to light emitted by the intensifying screens when struck by X-rays. Dye sensitization of the silver halide is well understood in the art. Upon determination of the emission spectrum of the particular phosphor selected, one can readily select sensitizing dyes which are known to sensitize silver halide crystals to the appropriate region of the spectrum, usually between 400 and 780 nanometers.
  • the silver halide is sensitized to a spectral range within 25 nanometers of the maximum wavelength emission of the screen (Amax), more preferably within 15 nm, and most preferably within 10 nm.
  • the invention also provides 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, 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.
  • Radiographic emulsions used in the practice of the present invention should have silver coating. weights less than 10 g Ag/m 2 and preferably between 3 and 8 grams of silver per square meter. The most preferred range is between 3 and 7 g/m 2 of silver. These films have enabled complete processing times to be reduced to as little as ninety seconds.
  • the process would be performed by using a conventional X-ray projection source or other high energy particle radiation sources including gamma and neutron sources.
  • the particular phosphor used should have a high absorption coefficient for the radiation emitted from the source.
  • this radiation is high energy particle radiation which is defined as any of X-rays, newtrons and gamma radiation.
  • the industrial material would be placed between the controllable source of X-rays and the industrial radiographic system of the present invention. A controlled exposure of X-rays would be directed from the source and through the industrial material so as to enter and impact the radiographic system at an angle approximately perpendicular to the plane or surface of the intensifying screen and the photographic film contiguous to the inside surface of the screen.
  • the radiation absorbed by the phosphors of the screen would cause light to be emitted by the screen which in turn would generate a latent image in the two silver halide imaging layers.
  • Conventional development processes including stop baths, washes, fixing, bleaching and the like would then be used on the exposed film.
  • the silver halide grains may be selected from amongst any of the known photographic silver halide materials such as silver chloride, silver bromide, silver iodide, silver bromoiodide, silver chlorobromoiodide, silver chlorobromide, and the like and mixtures thereof.
  • photographic adjuvants and processing aids may be used in the practice of the present invention.
  • materials include gelatin extenders, chemical sensitizers (including sulfur and gold compounds), development accelerators (e.g., onium and polyonium compounds), alkylene oxide polymer accelerators, antifoggant compounds, stabilizers (e.g., azaindenes especially the tetra- and pentaazaindenes), surface active agents (particularly fluorinated surfactants), antistatic agents (particularly fluorinated compounds), plasticizers, matting agents, hardening agents, hardening accelerators, and the like.
  • chemical sensitizers including sulfur and gold compounds
  • development accelerators e.g., onium and polyonium compounds
  • alkylene oxide polymer accelerators e.g., antifoggant compounds
  • stabilizers e.g., azaindenes especially the tetra- and pentaazaindenes
  • surface active agents particularly fluorinated surfactants
  • the base may be any one of the well known photographic support materials such as glass, polymeric films such as cellulose acetate (and triacetate), polyesters (particularly polyethyleneterephthalate), polycarbonates, polystyrene, and polyvinyl acetal film base. Many other materials may also be used.
  • photographic support materials such as glass, polymeric films such as cellulose acetate (and triacetate), polyesters (particularly polyethyleneterephthalate), polycarbonates, polystyrene, and polyvinyl acetal film base. Many other materials may also be used.
  • the dye underlayer must contain a decolorizable dye.
  • decolorizable it is meant that the light absorbing ability of the dye must be substantially diminishable or capable of being completely removed.
  • the dye in the binder which forms the underlayer may be readily soluble in aqueous alkaline solutions used in the processing (developing) of the film element so that the dye would be washed out of the element.
  • the dye could be alkaline solution bleachable, heat bleachable, sulfite bleachable, or removable in any other manner which would not require destruction of the image in the film.
  • Heat bleaching of the dyes may be accomplished by selecting dyes which are themselves thermolabile or by combining them with materials which can bleach the dyes when heated.
  • the combination of bleachable dyes with nitrate salts capable of liberating HN0 3 , or nitrogen oxides when heated to 160-200°C are particularly desirable.
  • the dye underlayer is particularly important because it prevents cross-talk within the radiographic element.
  • Cross-talk occurs when light emitted from one screen passes through one silver halide emulsion and the base into the second silver halide emulsion and forms a latent image there.
  • the second emulsion i.e., the emulsion on the side of the base away from the emitting screen under consideration
  • the second emulsion is relatively far removed from the screen, the light image is greatly dispersed and the resolution would be greatly reduced. It is, therefore, essential that the dye underlayer absorb radiation of the wavelength emitted by the phosphors.
  • a series of silver halide emulsions with narrow grain size distribution was made in which the grain size was varied from 0.20 to 0.6 micrometers.
  • the emulsions were made using a double jet procedure under controlled pAg conditions.
  • the grains in all cases were iodobromide in composition containing 2.75 mole % iodide and were of cubic habit.
  • the emulsions were handled in the normal manner for coagulating, washing and reconstituting them.
  • the reconstituted emulsions were treated with conventional sulfur and gold sensitizers and were digested at 55°C to increase their sensitivity, cooled to 40°C, and treated with post sensitization additives and stabilizers (namely, tetraazaindines, additional halides, antifoggants, and a spectral sensitizer chosen to provide maximum sensitivity at 550 nm which matches the maximum emission characteristics of 3M's Trimax@ intensifying screen) as is common to the art.
  • post sensitization additives and stabilizers namely, tetraazaindines, additional halides, antifoggants, and a spectral sensitizer chosen to provide maximum sensitivity at 550 nm which matches the maximum emission characteristics of 3M's Trimax@ intensifying screen
  • the photographic films were prepared by separately coating the above emulsion onto both sides of a polyester film base which had previously been coated with an aqueous alkaline soluble dye in a gelatin layer.
  • the film base was 1.8x 10- 4 m. (7 mil) photograde polyester.
  • the emulsions were applied using a precision photographic coating machine.
  • the final coatings contained 5.1 g Ag/m 2 .
  • This example shows the use of the materials of the present invention in commercial industrial radiographic situations.
  • the X-ray intensifying screens used in the practice of the present invention are phosphor screens well known in the art. These phosphors are materials which absorb incident X-rays and emit radiation in a different portion of the electromagnetic spectrum, particularly visible and ultraviolet radiation. Calcium tungstate and rare earth (gadolinium and lanthanum) oxysulfides and gadolinium or lanthanum oxybromides are particularly useful phosphors.
  • the gadolinium oxysulfides and the lanthanum oxysulfides and the phosphates and arsenates can be doped to control the emussion wavelengths and improve their efficiency. Many of these phosphors are shown in U.S. Patent No. 3,725,704 and U.K. Patent No.
  • the phosphate and arsenate phosphors may be generally represented by the formula wherein a is 0.01 to 0.50, b is 0 to 0.50, c is 0 to 0.02, d is 0 to 0.10, e is 0 to 0.02 and X represents phosphorous or arsenic atoms or mixtures thereof.
  • c is 0, a is 0.05 to 0.30 and d is 0 to 0.02.
  • the sum of b, c, d and e should be greater than zero and should most preferably be at least 0.005.
  • the oxysulfide rare earth phosphors may be represented by the formula wherein Z is'the dopant element or elements,
  • g is 0 to 1.99
  • h is 0 to 1.99
  • f is 0.0005 to 0.16.
  • b is 0, a is 0.15 to 1.00, f is 0.0010 to 0.05 and Z is terbium.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
  • Conversion Of X-Rays Into Visible Images (AREA)

Claims (6)

1. Industrie-Röntgensystem mit zwei zur Verstärkung von Hochenergie-Teilchenstrahlung dienenden Leuchtschirmen, zwischen denen ein strahlungsempfindliches Element angeordnet ist, das folgende Teile umfaßt:
1) Einen Tragkörper,
2) auf mindestens einer Seite des Tragkörpers eine entfärbbare Farbstoff-Unterschicht,
3) über der Farbstoff-Unterschicht eine erste Silberhalogenid-Emulsionsschicht und
4) auf der anderen Seite des Tragkörpers eine zweite Silberhalogenid-Emulsionsschicht,

wobei die beiden Silberhalogenid-Emulsionsschichten auf die Wellenlänge der Strahlung sensibilisiert sind, die von den Leuchtschirmen beim Einfall von Hochenergie-Teilchenstrahlung emittiert wird, dadurch gekennzeichnet, daß die Silberhalogenidkörner in den Emulsionen eine durchschnittliche Korngröße zwischen 0,05 und 0,4 pm haben.
2. System nach Anspruch 1, dadurch gekennzeichnet, daß die genannten Leuchschirme Röntgenstrahlen-Verstärkerschirme sind.
3. System nach Anspruch 2, dadurch gekennzeichnet, daß die durchschnittliche Korngröße zwischen 0,075 und 0,35 pm beträgt.
4. System nach Anspruch 2 oder 3, dadurch gekennzeichnet, daß die Emulsionen mit mindestens einem aensibilisierenden Farbstoff derart sensibilisiert sind, daß ihre maximale Empfindlichkeit bei einer Wellenlänge liegt, die von der von den Bildschirmen emittierten Wellenlänge höchster Intensität um nicht mehr als 25 nm abweicht.
5. System nach Anspruch 2 oder 3, dadurch gekennzeichnet, daß die Leuchtstoffe der genannten Leuchtschirme mindestens teilweise aus den Gadoliniumoxysulfiden, den Lanthanoxysulfiden, den Gadolinium-Landthanoxysulfiden, den Gadoliniumoxybromiden, den Lanthanoxybromiden oder den Lanthan-Gadoliniumoxybromiden bestehen.
6. Verfahren zum zerstörungsfreien Prüfen von industriellen Werkstoffen, in dem ein industrieller Werkstoff zwischen einer gesteuerten Röntgenstrahlenquelle und dem Röntgensystem angeordnet wird und Röntgenstrählen von der Quelle durch den industriellen Werkstoff hindurch in das Röntgensystem annähernd rechtwinklig zu den Verstärkerschirmen abgegeben werden, so daß in der ersten und der zweiten Silberhalogenid-Bildaufnahmeschicht ein latentes Bild erzeugt wird, dadurch gekennzeichnet, daß das Röntgensystem ein System nach Anspruch 2 ist.
EP82302617A 1981-05-26 1982-05-21 Industrielles Röntgenstrahlungssystem Expired EP0065877B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US26740281A 1981-05-26 1981-05-26
US267402 1988-11-04

Publications (2)

Publication Number Publication Date
EP0065877A1 EP0065877A1 (de) 1982-12-01
EP0065877B1 true EP0065877B1 (de) 1986-08-06

Family

ID=23018616

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82302617A Expired EP0065877B1 (de) 1981-05-26 1982-05-21 Industrielles Röntgenstrahlungssystem

Country Status (10)

Country Link
EP (1) EP0065877B1 (de)
JP (1) JPS57198456A (de)
AR (1) AR241831A1 (de)
AU (1) AU550866B2 (de)
BR (1) BR8203024A (de)
CA (1) CA1196733A (de)
DE (1) DE3272443D1 (de)
ES (1) ES8308075A1 (de)
MX (1) MX157370A (de)
ZA (1) ZA823627B (de)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU589980B2 (en) * 1985-05-29 1989-10-26 Cancer Institute Board, The Method and apparatus for high energy radiography
CA1271567A (en) * 1985-05-29 1990-07-10 Cancer Institute Board, (The) Method and apparatus for high engery radiography
IT1185307B (it) * 1985-07-25 1987-11-12 Minnesota Mining & Mfg Materiali fotosensibili per uso in radiografia e procedimento per la formazione di una immagine radiografica
DE3614476A1 (de) * 1986-04-29 1987-11-12 Du Pont Deutschland Aufzeichnungssystem fuer die strahlentherapie
IT1226917B (it) * 1988-07-14 1991-02-22 Minnesota Mining & Mfg Combinazione di elementi fotosensibili da usare in radiografia.
EP0384634A3 (de) * 1989-02-23 1990-11-07 Eastman Kodak Company Radiographische Schirm/Film-Konstruktionen mit verbesserter Quantendetektionsleistungsfähigkeit
EP0437117A1 (de) * 1990-01-10 1991-07-17 Konica Corporation Photographisches lichtempfindliches Silberhalogenidmaterial mit verbesserten diagnostischen Eigenschaften
JP2770205B2 (ja) * 1991-10-24 1998-06-25 富士写真フイルム株式会社 放射線画像読取方法ならびにエネルギーサブトラクション方法

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0028521A1 (de) * 1979-10-31 1981-05-13 EASTMAN KODAK COMPANY (a New Jersey corporation) Grün emittierende Röntgen-Verstärkerschirme

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3005104A (en) * 1958-09-17 1961-10-17 Knapp Mills Inc Method and means for testing metals
JPS4830497B1 (de) * 1969-11-21 1973-09-20
US3725704A (en) * 1971-01-28 1973-04-03 Lockheed Aircraft Corp Rare earth phosphors for x-ray conversion screens
US4130428A (en) * 1971-11-05 1978-12-19 Agfa-Gevaert, N.V. Combination of photosensitive elements suited for use in radiography
GB1477639A (en) * 1974-03-11 1977-06-22 Agfa Gevaert Nv Photo-sensitive combination of elements suited for use in radiography
US3922545A (en) * 1974-02-26 1975-11-25 Eastman Kodak Co Process for nondestructively testing with a desensitized silver halide radiographic layer
JPS5179593A (en) * 1975-01-06 1976-07-10 Dainippon Toryo Kk Zokanshi
JPS5857735B2 (ja) * 1975-01-22 1983-12-21 株式会社日立製作所 放射線検知フイルム
US4210715A (en) * 1975-08-02 1980-07-01 Konishiroku Photo Industry Co., Ltd. Light-sensitive silver halide photographic material and method of processing thereof
DE2540344A1 (de) * 1975-09-10 1977-03-17 Siemens Ag Mit roentgenstrahlen zur fluoreszenz anregbarer leuchtstoff
GB1565811A (en) * 1976-06-28 1980-04-23 Minnesota Mining & Mfg Luminescent phosphor materials
JPS53106125A (en) * 1977-02-28 1978-09-14 Fuji Photo Film Co Ltd Dyestuff image recording

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0028521A1 (de) * 1979-10-31 1981-05-13 EASTMAN KODAK COMPANY (a New Jersey corporation) Grün emittierende Röntgen-Verstärkerschirme

Also Published As

Publication number Publication date
AU8413882A (en) 1982-12-02
JPH0473136B2 (de) 1992-11-20
DE3272443D1 (en) 1986-09-11
BR8203024A (pt) 1983-05-10
EP0065877A1 (de) 1982-12-01
ES512479A0 (es) 1983-08-01
ZA823627B (en) 1983-05-25
ES8308075A1 (es) 1983-08-01
JPS57198456A (en) 1982-12-06
AR241831A1 (es) 1992-12-30
AU550866B2 (en) 1986-04-10
CA1196733A (en) 1985-11-12
MX157370A (es) 1988-11-18

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