摘要
研究饱和蒸汽热处理过程中竹材颜色的变化规律,以期为竹材的开发利用提供理论和实验依据。采用国际照明委员会颜色系统CIE 1976 L^*a^*b^*标准色度系统,研究饱和蒸汽热处理毛竹竹片过程中竹片初始含水率和热处理时间对其颜色的影响。结果表明,在热处理过程中,竹材颜色从浅黄色变为深红褐色,整体颜色变化均匀。竹材初始含水率和热处理时间对a^*、b^*和L^*均具有较大的影响。随着热处理时间的增加,a^*先升高再降低,b^*和L^*主要呈现下降的趋势。同时,随着竹材亮度的降低,a^*以一种类似抛物线的趋势变化,而b^*主要呈现直线降低的趋势,但均大于0,表明竹处理材偏红、偏蓝。热处理时间对竹材总色差(ΔE^*)的影响主要集中在10~20 min,且ΔE^*受明度差(ΔL^*)的影响较大,而黄蓝色品差(Δb^*)对ΔE^*的影响大于红绿色品差(Δa^*)。此外,处理后竹材的颜色饱和度(C^*)和饱和度差值(ΔC^*ab)均随着热处理时间的增加而降低,而色度变化(ΔC^*)的变化趋势则相反。不同初始含水率的竹材之间,颜色亮度和黄蓝度主要分布范围差异不大,而红绿度差异较大。三大素检测结果显示,处理材颜色的差异主要是由不同初始含水率引起化学成分不同导致的。
Color frequently is one of the most valuable characteristics for a material,as it is an important aesthetic component.One method of changing bamboo-based materials color without adding dyes is the thermal modification.In order to study the response of bamboo color to different heat treatment time durations and initial moisture contents in the process of saturated steam heat treatment,and to determine the influence of the saturated steam heat treatment process on bamboo color characteristics,bamboo slices with various initial moisture contents(25%,30%,40%,50%and 65%)were heat-treated by saturated steam of 180℃with different times(10,20,30,40 and 50 min).The color change of the treated bamboo slices was quantitatively tested,and CIE 1976 L^*a^*b^*standard chroma system was used for the analysis.The results showed that during the heat treatment,the bamboo color changed from light yellow to dark red brown,and the overall color changed evenly.The initial moisture content and heat treatment time had great influence on a^*,b^*and L^*of the bamboo.Among them,a^*increased firstly and then decreased,indicating that the treated bamboo slices were reddish,while b^*and L^*mainly showed a downward trend,indicating that the treated bamboo was bluer and darker.As the brightness of bamboo decreased,the a^*changed in a parabola-like trend,while the b^*decreased in a straight line,but both of them were greater than 0.After being treated with various treatment times,the main distribution ranges of L^*and b^*were not significantly different from the initial moisture content,but the variation ranges of a^*were somewhat different.Under the same initial moisture content,the effect of the heat treatment time on the overall color difference(ΔE^*)was mainly concentrated in 10-20 min,which was greatly affected by the brightness difference(ΔL^*).The effect of yellow-blue difference(Δb^*)onΔE^*was greater than that of red-green difference(Δa^*).In addition,the color saturation difference(C^*)and saturation difference(ΔC^*ab)of the treated bamboo slices decreased with the increase of the heat treatment time,while the change trend of chromaticity variation(ΔC^*)was opposite.The results showed that the difference in color of the treated bamboo was mainly caused by the difference of chemical composition caused by the initial moisture content.
作者
娄志超
杨林添
张爱文
沈道海
刘杰
袁成龙
李延军
LOU Zhichao;YANG Lintian;ZHANG Aiwen;SHEN Daohai;LIU Jie;YUAN Chenglong;LI Yanjun(College of Materials Science and Engineering,Nanjing Forestry University,Nanjing 210037,China;Fujian Huayu Group Bamboo Industry Co.Ltd.,Jianou 353100,Fujian,China;Hangzhou Dasuo Technology Co.Ltd.,Xiaoshan 311251,Zhejiang,China)
出处
《林业工程学报》
CSCD
北大核心
2020年第4期38-44,共7页
Journal of Forestry Engineering
基金
国家重点研发计划(2017YFD0600801)
江苏省农业科技自主创新资金项目[CX(18)3033]
浙江省竹资源与高效利用协同创新中心开放项目(2017ZZY2-06)
江苏省科技计划项目(BE2018391)
福建省科技计划项目(2019N3014)。
关键词
竹材
颜色
饱和蒸汽热处理
CIE
含水率
bamboo
color
saturated steam heat treatment
CIE
moisture content
