High contrast photographic elements containing ballasted hydrophobic
isothioureas
    4.
    发明授权
    High contrast photographic elements containing ballasted hydrophobic isothioureas 失效
    含有BALASTED HYDROPHOBIC同位素的高对比摄影元素

    公开(公告)号:US5126227A

    公开(公告)日:1992-06-30

    申请号:US599218

    申请日:1990-10-17

    IPC分类号: G03C1/06

    CPC分类号: G03C1/061

    摘要: Silver halide photographic elements which are capable of high contrast development, when processed in the presence of a hydrazine compound that functions as a nucleating agent, contain both an amino compound which functions as an incorporated booster and a ballasted hydrophobic isothiourea compound comprising a ballasting group, that is attached to the sulfur atom, which serves to restrict the mobility of the compound and thereby aid in retaining it in the photographic element during development. The ballasted hydrophobic isothiourea compound is highly effective in reducing pepper fog and also serves to restrain image spread.

    Black and white photographic elements containing release compounds and
method of preparing photographic emulsion
    9.
    发明授权
    Black and white photographic elements containing release compounds and method of preparing photographic emulsion 失效
    含有释放化合物的黑色和白色照相元件和制备照相乳剂的方法

    公开(公告)号:US5500338A

    公开(公告)日:1996-03-19

    申请号:US455944

    申请日:1995-05-31

    摘要: The invention provides a black and white photographic element comprising a support having situated thereon at least one silver halide emulsion, the element containing a release compound that provides a non-imagewise distribution of a photographically active moiety, wherein the release compound has the structure ##STR1## wherein R.sup.1 is an electron withdrawing moiety;m is 0, 1, 2 or 3;R.sup.2 is a group containing an aqueous solubilizing group;q is 1 or 2;TIME is a timing group;n is 0, 1, 2 or 3; andPAM is a photographically active moiety.Also provided is a method of preparing a photographic emulsion comprising precipitating silver halide grains in a colloidal medium, washing the grains, sensitizing the grains by adding dyes, chemical sensitizers and heating, and adding to the emulsion a methanolic solution comprising a release compound as described above.

    摘要翻译: 本发明提供了一种黑色和白色照相元件,其中包含一个载体,其上至少有一个卤化银乳剂,该元素含有提供摄影活性部分的非成像分布的释放化合物,其中该释放化合物具有结构其中R 1是吸电子部分; m为0,1,2或3; R2是含有水溶性基团的基团; q为1或2; TIME是一个时间组; n为0,1,2或3; 并且PAM是照相活性部分。 还提供了一种制备照相乳剂的方法,其包括在胶体介质中沉淀卤化银颗粒,洗涤晶粒,通过添加染料,化学增感剂和加热使颗粒致敏,并向乳液中加入包含如上所述的释放化合物的甲醇溶液 以上。