Radiographic image forming method

• US 5,834,153 A
• Filed: 11/15/1996
• Issued: 11/10/1998
• Est. Priority Date: 11/20/1995
• Status: Expired due to Fees

• Current Assignee: Konica Corporation (Konica Minolta Inc.)
• Original Assignee: Konica Corporation (Konica Minolta Inc.)
• Inventors: Ohara, Hiromu, Hasegawa, Takuji
• Primary Examiner(s): Chea, Thorl
• Application Number:
  US08/746,740
• Time in Patent Office: 725 Days
• Field of Search: 430/139, 430/966, 428/690, 252/301.4 R
• US Class Current: 430/139
• CPC Class Codes: G03C 5/17 using screens to intensify X-ray images X-ray conversion screens G21K4/00
• CPC Class Codes: G21K 2004/06 with a phosphor layer
• CPC Class Codes: G21K 4/00 Conversion screens for the conversion of the spatial distribution of X-rays or particle radiation into visible images, e.g. fluoroscopic screens photographic processes using X-ray intensifiers G03C5/17; discharge tubes comprising luminescent screens H01J1/62; cathode ray tubes for X-ray conversion with optical output H01J31/50
• CPC Class Codes: Y10S 430/167 X-ray

Abstract

A radiographic image forming method is disclosed. The method comprises the steps of (1) interposing a silver halide photographic material which comprises a support having a silver halide emulsion layer on each of both sides the support and has a cross-over value of not more than 15%, between two sheets of an intensifying screen comprising a support and a fluorescent layer composed of plural fluorescent sub-layers and a protect layer provided on the support in this order from the support, in which the fluorescent sub-layers each comprises a binder and particles of a fluorescent substance having the average particle size R and the standard deviation σ of the particle size distribution satisfying a relation of 0 <σ/R≦0.5 and the values of R of the particles contained in each of the fluorescent sub-layers are different from each other, (2) imagewise exposing to radiation the intensifying screens and the silver halide photographic light-sensitive material interposed between the intensifying screens, and (3) processing the imagewise exposed light-sensitive material with processing solutions including a developing solution to forming a radiographic image.

Claims

1. A radiographic image forming method comprising interposing a silver halide photographic material between two sheets of an intensifying screen, said photographic material comprising a support with a silver halide emulsion layer on each side and having a crossover value not exceeding 15%,

each of said intensifying screens comprising a support, a fluorescent layer, and a protective layer on said fluorescent layer,

said fluorescent layer including a plurality of sub-layers, each of which comprises a binder and particles of a fluorescent substance having an average particle size R and a standard deviation σ

of particle size distribution satisfying the relation

space="preserve" listing-type="equation">O<

σ

/.sub.R ≦

0.5

one of said sub-layers having a largest R value and another of said sub-layers having a smallest R value, said largest R value being from 10 μ

m to 20 μ

m and said smallest R value being from 1 μ

m to 5 μ

m.

2. The method of claim 1, wherein the radiographic image has a contrast G of from 1.5 to 2.2.