申请人:Eastman Kodak Company
公开号:US05292631A1
公开(公告)日:1994-03-08
Monocyclic and polycyclic azoles having the following formula enhance the covering power of a developed silver image formed from a radiographic element comprising a radiation sensitive tabular grain silver bromide, silver bromochloride or silver bromoiodide emulsion layer containing grains having a mean equivalent circular diameter of at least 0.3 .mu.m and a grain population wherein at least 50 percent of the total grain population projected area is accounted for by tabular grains having a tabularity of greater than 8, as determined by the relationship: ##EQU1## wherein T is tabularity; ECD is the mean effective circular diameter in .mu.m of the tabular grains; and t is the mean thickness in .mu.m of the tabular grains. The azoles have the formula: ##STR1## wherein Z is --N.dbd. or --C(R.sup.5).dbd. where R.sup.5 is hydrogen, --NH.sup.2, aliphatic of 1 to 8 carbon atoms or aromatic of 1 to 8 carbon atoms; R.sup.4 is hydrogen, aliphatic of 1 to 8 carbon atoms or aromatic of 1 to 8 carbon atoms; R.sup.4 and R.sup.5 together complete a 5 or 6 membered heterocyclic nucleus containing 1 to 3 ring nitrogen atoms; L is a divalent aliphatic linking group containing 1 to 8 carbon atoms; T is an aliphatic terminal group containing 1 to 10 carbon atoms; m is 0 or 1; n is an integer of 0 to 4; and p is an integer of 2 to 4.
具有以下公式的单环和多环杂环化合物增强了由放射成像元素形成的发展银图像的覆盖力,该放射成像元素包括具有平均等效圆直径至少为0.3μm和至少50%的总晶粒面积由具有大于8的平板晶粒的平板状晶粒组成的辐射敏感的板状颗粒银溴化物,银溴氯化物或银溴碘化物乳液层。其中,平板度T由以下关系确定:T =(ECD / t)其中ECD是平板晶粒的平均有效圆直径(μm),t是平板晶粒的平均厚度(μm)。这些杂环化合物的公式为:其中Z为--N.dbd.或--C(R.sup.5).dbd.,其中R.sup.5为氢,--NH2,1至8个碳原子的脂肪族或1至8个碳原子的芳香族;R.sup.4为氢,1至8个碳原子的脂肪族或1至8个碳原子的芳香族;R.sup.4和R.sup.5共同组成一个含有1至3个环氮原子的5或6元杂环核;L为含有1至8个碳原子的二价脂肪族连接基;T为含有1至10个碳原子的脂肪族末端基;m为0或1;n为0至4的整数;p为2至4的整数。