着色介质及表面粗糙度对热固化基托树脂着色的影响

Effects of coloring agents and surface roughness on the coloring of heat-cured base resin

目的:研究4种着色介质对不同表面粗糙度的热固化基托树脂的表面着色状况。方法:制作64个热固化基托树脂试件,随机分成4组,不同组试件的测试面打磨出不同的粗糙度等级,用表面粗糙度轮廓仪测量其表面粗糙度参数Ra并记录,然后将每组试件分别浸泡于蒸馏水(对照)、咖啡、茶和陈醋中,用分光光度比色仪测量试件浸泡前及浸泡4周后的颜色,得到L*、a*、b*值,计算浸泡前后的色差△E,采用统计学方法,分析热固化基托树脂着色与上述因素的关系。结果:除对照组外,咖啡组和茶组试件的色差值△E均增大(P<0.05),且咖啡组的△E大于茶组(P<0.05),陈醋组的△E无明显改变(P>0.05);同一浸泡液中不同表面粗糙度的试件的△E值差异有显著性(P<0.05),表面粗糙度越大,△E越大。结论:外源性色素能引起基托树脂的着色,并且树脂表面越粗糙,着色越明显。

Objective： To study the staining of heat-cured base resin with different surface roughness by different coloring agents.Methods：64 specimens（20 mm×20 mm×5 mm） made of heat-cured base resin were divided into 4 groups（n=16） and then different surface roughness degree were produced for different groups.A surface roughness tester was used to measure Ra along 3 tracks on each surface.The specimens in the 4 groups were immersed in coffee,tea,vinegar and water（n=4 for each coloring agent） respectively and treated for 4 weeks.The initial and further color values of each specimen were measured using a colorimeter.The CIE L＊a＊ b＊ values were recorded and color differences（△E） after staining were calculated.Data were statistically analyzed using analysis of variance（ANOVA）.Results： The △E of the specimens in coffee and tea was significantly affected by the immersion solutions（P0.05）,and the higher（△E） was observed in the samples treated by coffee than by tea（P0.05）.There were no statistically evidence of color change in water and in vinegar（P0.05）.The specimens with greater surface roughness demonstrated the higher △E（P0.05）.Conclusion：Extrinsic pigment may stain heat-cured base resin,the rough surface can increase the staining susceptibility.