木材变色的研究状况及展望

介绍了木材变色问题的国内外研究现状,给出了木材防变色方法和对已变色木材的除色方法,并对未来的研究方向提出了自己的看法和见解。     

木材诱发变色研究现状与趋势

介绍了木材诱发变色的变色机理, 从光变色和热变色2个方面分析了木材变色是内因在外因的诱导下发生的自身化学成份的变化, 探讨了材色的评价方法、诱发变色及变色的防护方法, 并指出木材诱发变色的研究方向。     

木材微生物变色与调控研究现状和展望

木材变色是一种木材材性的缺陷,木材调色是木材变色现象的逆利用。利用微生物调控木材材色环保无污染,具有较好的发展前景。综述了易变色的木材种类、易使木材变色的菌种、微生物控制木材变色和腐朽以及微生物诱导木材调色的研究现状,并对今后木材微生物变色与调控的发展提出建议。     

拼木地板的木材染色处理

随着生活的富裕，人们越来越注重室内装修。拼木地板因其具有美丽花纹、隔热、导电不良、防滑和较高的强重比等特性，在室内装修中占很重要位置。然而，木材属生物材料，它会因各种原因而导致变色。除生物降解引起木材腐朽以外，变色对木地板的强度、耐磨性影响不大。但变色及材色不均影响了木材美观和销售竞争力。而染色可以改良不均一的材色，并可以仿制名贵木材，提高木材的经济价值和使用范围，节省贵重木材。但木材中木素及抽提物成分与天然纤维素混在一起，所以在染料的溶剂及染色方法等方面都受到一定制约。受安徽某厂委托，我们对种…     

温敏变色粉对木质家具表面漆膜性能的影响

将温敏变色粉应用到木质家具涂料中,分析温敏变色粉的加入对涂饰后家具表面的色差、漆膜附着力和漆膜光泽度的影响,可以进一步发展智能响应材料在木质家具中的应用,得到与传统涂饰方法不同的装饰效果。结果表明:室温条件下,温敏变色粉的加入,使得涂饰木材表面的材色发生变化,色差显著增加。升高温度至温敏变色粉响应温度后,添加3%～10%温敏红和3%温敏蓝的清漆涂饰木材表面材色发生消色现象,色差值降低,表面材色恢复至与未添加温变粉的涂饰木材表面材色相近的状态;扫描电镜下观察温敏蓝和温敏红两种类型的变色粉微囊外观形态良好,表面较为光滑,多为球形结构,温敏蓝微胶囊的平均粒径为3.94μm,温敏红微胶囊的平均粒径为3.27μm。而在清漆中添加温敏变色粉后,漆膜表面变得粗糙,随着温敏变色粉添加比例的上升,漆膜表面出现了颗粒的团聚。而在油性清漆中添加温敏变色粉时,涂饰漆膜表面的粗糙感并没有水性漆漆膜明显。添加3%比例的温敏变色粉对涂饰木材的漆膜附着力和光泽度并未产生显著性影响;涂饰木材的表面材色表现出良好的变色耐久性。     

防止兰考泡桐木材变色的初步试验

对多种化学药品配方防止兰考泡桐(Paulownia elongata)木材变色的效果进行了试验,并观测了处理前后材色的变化,探索到4种对防止变色有一定作用的配方。同时,初步观察了干燥条件和木材含水率对变色的影响,讨论了各种处理方法对防止兰考泡桐材变色的适用性。     

西加云杉木材单宁铁变色因素及防治

为解决西加云杉木材加工中的铁变色问题,研究了西加云杉木材内单宁引发铁变色的因素,并探寻铁变色化学防治方法,为其加工利用提供理论依据。采用CIE-L~*a~*b~*色度体系对西加云杉木材的铁变色现象进行评价,通过控制变量法分别研究木材含水率(40%,60%,80%和饱水状态)、铁离子质量分数(0.01%,0.05%,0.1%,0.5%和1%)、反应温度(25,45,65,85和95℃)及时间(0 min、1 min、5 min、10 min、30 min、1 h、6 h、12 h和24 h)等因素对西加云杉木材表面颜色的影响,并研究了草酸、次磷酸、磷酸二氢钠、乙二胺四乙酸二钠(EDTA·2Na)试剂对西加云杉木材铁变色防治处理的效果。结果表明:以上因素均对西加云杉木材的铁变色有不同程度的影响,其中,铁离子质量分数、反应温度和反应时间等因素都与变色严重程度呈正相关,即铁离子质量分数为0.01%、反应温度为25℃,反应时间为1 min时木材变色程度均最小。当含水率为40%时,变色严重程度相对较低;当含水率高于40%时,变色程度随含水率增加有增大趋势;当含水率为60%左右时,变色程度较为严重;之后,变色程度在一定范围内波动。2%草酸、5%磷酸二氢钠和2%草酸+5%磷酸二氢钠的组合均能有效防治铁变色;3%草酸对消除铁变色有一定效果,当加入0.5%EDTA·2Na螯合剂时效果更优,为避免返色,应选择3%草酸+0.5%EDTA·2Na药剂进行除色处理。当铁离子质量分数较低时,可通过降低木材含水率、避免高温及长时间接触来减轻铁变色现象;通过对其加工表面喷涂2%草酸、5%磷酸二氢钠或2%草酸+5%磷酸二氢钠试剂组合可以有效预防木材铁变色;对于已经发生铁变色的木材,可采用3%草酸配合0.5%EDTA·2Na进行涂刷处理,消除已产生的变色。     

杨树木材变色病病原菌的鉴定

杨树木材变色病已影响了我国木材工业从粗放加工型向精细加工型的发展,已给木材工业带来重大经济损失。山东杨树木材变色病主要为褐变和红变。经分离培养、纯化、接种试验,依其培养性状和形态学特征,鉴定出杨树褐变、红变变色病的病原菌分别为Lasiodiplodia theobromae和Fusarium decemcellulare。     

白桦木材常规干燥变色规律的研究

针对白桦存在的干燥变色这一缺陷,从干燥变色规律方面展开系统研究,结果表明,白桦木材材色随干燥温度和相对湿度的增加而加深,80℃和70％的相对湿度是材色速增的临界值.     

关于兰考泡桐木材变色成分的初步研究

用含水乙醇提取兰考泡桐木材的浸提物,将其分为可溶于石油醚、氟仿、乙醚、乙酸乙酯和水5种溶剂的级分,在滤纸和泡桐材单板上分别进行模拟变色观察试验,肯定了使该木材发生棕红色变色的成分主要存在于水溶部分。对水溶部分的分析结果表明,无色花色甙和原花色甙类化合物是主要的变色成分。对变色成分的性质和影响变色的因素也进行了简要的讨论。     

木材干燥变色的研究现状及其发展趋势

木材在干燥过程中产生的干燥变色导致木材使用价值和利用率的降低,这已经引起了国内外研究者的普遍关注。就近年来木材在干燥过程中诱发变色的研究进展予以评述,为木材干燥变色的深入研究以及木材资源的高效利用提供参考。     

泡桐材变色类型的确定及变色真菌的鉴定

对泡桐材变色类型的研究表明,泡桐材变色存在着真菌变色。同时从新伐的泡桐木材中分离出两种真菌,经鉴定是链格孢菌和一种根霉菌,这两种真菌可引发泡桐木材变色。     

Induced discoloration of buerger maple during drying process

Buerger maple (Liquidambarformosana Hance) is a kind of wood that is easily discolored. This paper tries to obtain satisfactory color and a broad prospect in the utilization of buerger maple by induced discoloration. The authors analyze the mechanism of induced discoloration of buerger maple based on the analysis of visual physical parameter, the infrared spectrum (IRS) and the scanning electron microscope (SEM) under different drying conditions. The result shows that it is feasible to induce discoloration during the drying process. The wood color tends to be red and fuscous during inducing discoloration of buerger maple.The induced discoloration mechanism is: 1) the high temperature and humidity accelerates the oxidation reaction of polyphenol,leuco-fancy pigment and tannin, which changes the wood color to red; 2) the hydroxy (-OH) is oxidized and the carbonyl (-C=0),carboxyl (-COOH), ester and ketone groups form during the high temperature steaming, which results in wood piece discoloration.     

FeCl2处理麻栎木材化学变色工艺及变色机理研究

通过化学试剂与木材中木质素、抽提物等成分发生反应,可以改变木材的颜色,从而达到对木材表面修饰的目的。以氯化亚铁(FeCl2)为变色剂,通过浸渍的方式获得了变色麻栎(Quercus acutissima)单板。利用正交试验研究了亚铁离子的质量分数、处理温度、处理时间以及干燥温度对麻栎单板变色的影响,获得了最佳处理工艺;利用色差仪对麻栎表面的色度系数进行了测试,并通过紫外漫反射光谱和红外光谱对麻栎变色的原因进行了探究。实验结果表明:经氯化亚铁溶液处理后,麻栎单板表面变为蓝黑色,颜色均匀,纹理清晰;影响麻栎单板变色的各因素主次顺序为氯化亚铁质量分数>干燥温度>处理温度>处理时间。氯化亚铁对麻栎进行化学变色处理的优化工艺参数为:氯化亚铁质量分数为1.0%、处理时间为10 min、处理温度为80℃、干燥温度为40℃。碱抽提可以去除麻栎单板表面大部分可以与铁离子发生变色反应的木质素或酚类物质,碱抽提后的麻栎不再发生明显的变色反应;麻栎与铁离子的变色反应,主要发生在木材的酚羟基和芳香环取代基上,木材中的酚类物质与铁离子络合反应是其变色的主要原因。     

仿生光子晶体结构色在木材颜色功能性改良中的应用前景

对木材表面进行颜色功能性改良是提高木材使用价值的重要途径.文中总结传统木材染色和诱导变色工艺的发展现状及存在的问题,提出利用结构色进行颜色改良是一种清洁无污染的生态仿生着色技术,综述其在木质材料领域中的研究现状,并从木质材料表面结构色构筑及机理、木质材料表面结构色的光响应及界面机理、木质材料表面仿生结构色薄膜大规模应用...     

木材光降解机理及研究进展

木材受紫外可见光照射后易发生降解, 表面的材色和力学性能都会下降, 大大影响木材的使用价值和美学特点。文中针对木材光降解机理进行了讨论, 在提出木质素是木材光降解中关键组分的同时, 强调了抽提物对木材光变色的具体影响; 通过详细叙述光降解过程中木材发生的化学变化, 进一步表明该过程中自由基中间体的生成和新的发色团的产生; 系统总结了影响木材光降解的主要因素, 并提出防治木材表面光降解的技术手段。     

Contribution of active defense responses in the limitation of fungal spread in the sapwood of living sugi (Cryptomeria japonica) tree

The participation of active defense responses in the limitation of fungal spread in the sapwood of living sugi tree was determined. Isolates ofGuignardia cryptomeriae were inoculated to living trees, fresh logs, frozen and thawed logs and autoclaved logs, and the spread of wood discoloration and fungal hyphae was assessed. In autoclaved logs and freeze-treated logs, wood discoloration and reaction zone formation were not observed, and fungal hyphae of both of virulent and avirulent isolates grew rapidly in the wood. In fresh logs, wood discoloration and the formation of a pale reaction zone and transition zone were observed. Virulent isolates spread rapidly, but the spread of avirulent isolates was inhibited. In living trees, wood discoloration was observed and reaction zones were formed at lesion margins. These results indicated that constitutive defense mechanisms had no effect on the spread of both of virulent and avirulent isolates, and that active defense responses were important in the limitation of spread of fungal hyphae, hence in the limitation of wood discoloration. Further, it appeared that avirulent, but not virulent, races ofG. cryptomeriae were easily inhibited even by weak host responses. This study was presented at 105th and 106th Annual Meeting of the Japanese Forestry Society.     

Effects of log storage and drying on birch (<Emphasis Type="Italic">Betula pendula</Emphasis>) wood proanthocyanidin concentration and discoloration

In conventional drying, sawn birch (Betula sp.) timber darkens and reddens from the inside while the layer a few millimetres under the yellowish surface remains light in color. Lack of information concerning the chemical basis of the discoloration hinders the development of a reliable solution for this problem. In this study, the role of soluble proanthocyanidins in discoloration of birch wood was investigated because the polymerization and oxidation of these compounds are known to yield insoluble reddish compounds. Different periods of log storage affected the synthesis of soluble proanthocyanidins during conventional drying. Concentration of proanthocyanidins also correlated with changes in the color of birch wood. Discoloration appeared differently in conventionally dried and vacuum-dried wood, which indicates that the discoloration mechanism in these drying methods may differ chemically, and/or the compounds that take part in discoloration may be different at different drying temperatures.     

简述木材退变色、漂白及染色

从3个方面扼要论述了影响木材变退色的因素、木材漂白的方法及其影响因子、染色处理。     

Decay development in living sapwood of coniferous and deciduous trees inoculated with six wood decay fungi

Development of decay and/or discoloration was assessed in the functional sapwood of one coniferous and three deciduous trees after wounding and artificial inoculation with six wood decay fungi. Living stems of mature Douglas fir, beech, oak, and sycamore trees were wounded in spring 2002 and immediately inoculated with brown, white, and soft rot fungi. Extent of discoloration and decay, wood weight loss, and total phenols in the reaction zone (zone of active response at a dynamic interface between living sapwood and wood colonized by decay fungi) were assessed 16 and 28 months after inoculation.