Synthesis and characterization of solubility enhanced metal-free phthalocyanines for liquid crystal display black matrix of low dielectric constant

For the liquid crystal display (LCD) black matrix (BM) with a low dielectric constant and high light absorption property, it is advantageous to employ dyes instead of carbon black or pigments. For this purpose, the dyes should have high solubility in industrial organic solvents. For improved solubility in industrial solvents, three metal-free phthalocyanines (PC), peripherally substituted with bulky groups, were synthesized and dye-based BMs were fabricated. The solubility as well as the spectral and thermal properties of the dyes were examined, and the optical, thermal and dielectric properties of a dye-based black matrix were tested. The greenish phthalocyanine dyes with high molar extinction coefficients and high thermal stability showed enhanced solubility in industrial solvents as a result of the greater steric hindrance among the dye molecules and higher affinity between the dye molecules and solvents. The dye-based BMs had low dielectric constants and exhibited superior optical properties and satisfactory thermal stability.     

Synthesis of yellow pyridonylazo colorants and their application in dye–pigment hybrid colour filters for liquid crystal display

Nine yellow azo dyes were designed and synthesised by using different diazo components and pyridonyl coupling components for application in dye–pigment hybrid colour filters for liquid crystal displays. The synthesised dyes were characterised by proton nuclear magnetic resonance and elemental analysis. The thermal stability was examined by thermogravimetric analysis, and solubility was estimated in industrial solvents such as N-methyl-2-pyrrolidone and propylene glycol methyl ether acetate. The dyes, which exhibited suitable physical properties for use in a dye–pigment hybrid colour filter, were fabricated into colour filters, and their optical properties were measured.     

彩色光刻胶用蒽醌染料的合成及稳定性研究

为实现彩色滤光片更高分辨率的发展需求，作为关键原材料的彩色光刻胶着色剂从颜料向染料体系转变是重要的趋势。然而染料分子的光热稳定性较差，亟需从分子结构方面探索提升稳定性的有效策略。以1,4,9,10-蒽四醇为原料，合成了9种1,4-二氨基取代的蓝色蒽醌染料分子，探索了不同取代基对染料分子光物理性质、溶解性以及光热稳定性的影响。结果表明，所有染料分子在590~600 nm和630~650 nm波长范围内呈现双吸收峰性质，具有高的摩尔消光系数。其中三甘醇及单甲醚取代的染料分子热分解温度为300℃，在230℃加热0.5 h后失重约2%，365 nm波长光照射8 h后色差低于1.73，表现出优异的光热稳定性。研究为进一步制备光热稳定性优异的彩色光刻胶用染料分子奠定了基础。     

Holographic polymer dispersed liquid crystal reflection gratings formed by visible light initiated thiol-ene photopolymerization

Visible laser light of wavelengths 442, 488 and 532 nm was used to write holographic reflection gratings with notches into the infra-red spectral region in polymer dispersed liquid crystals (H-PDLC). The gratings were formed by the spatially periodic phase separation of nematic liquid crystal during thiol-ene photopolymerization. An organic titanocene based complex, Rhodamine 6G (Rh6G) and Pyrromethene 597 (Pym) dyes in combination with benzoyl peroxide, were used as initiators. Using visible laser light and a single prism, electrically switchable reflection gratings with notches in the blue, green, yellow, red, and near infra-red (NIR) spectral regions were fabricated using angle tuning. The photophysics of the initiator dyes was studied by absorption and fluorescence spectroscopy. Morphology studies by TEM showed a periodic distribution of discrete nematic droplets of nearly spherical shape. The development of visible photoinitiator systems broadens the range of fabrication wavelengths of dynamic reflection filters using inexpensive visible lasers.     

电子纸技术及其应用

综述了电泳显示、旋转球显示和液晶显示及其他电子纸在彩色化、高反差、低能耗、快速响应等方面的研究进展,介绍了各种原理型显示技术的优缺点。纳米颗粒电泳、胆甾液晶、有机电致发光、隐色染料显示、无机电致发光等原理显示技术的开发,以及导电高分子薄膜晶体管的应用,使电子书、智能显示卡、无墨印刷、电子报纸等技术应用逐步成为现实。指出具有柔性、节能及大视角等特点的电泳显示、旋转球显示、有机电致发光电子纸是近几年的主要研究内容。     

Synthesis, thermal and optical properties of liquid crystalline terpolymers containing azobenzene and dye moieties

The synthesis, thermal properties and photochemical and photophysical studies of new azopolymers are described. These polymers contain three different types of monomer, each of which is mainly responsible for a particular function: A mesogenic benzanilide, a photochromic azobenzene and a dye unit (a benzoxazole, an anthracene or a stilbene derivative). This approach provides liquid crystalline terpolymers with different spectral properties and with the potential ability to be photoaligned by irradiation and thermotropic self-organization. The polymers have been prepared by random radical polymerisation of the corresponding methacrylate-fucntionalised units. All of the materials show good thermal stability and liquid crystalline behaviour, displaying smectic A or nematic mesophases. Optical properties of the polymers in solution display additive bands in the absorbance spectrum and luminescent properties in the emission region of the individual dye monomers. However, films of these polymers are not luminescent. A study of the absorption and redox properties of the dyes has been performed in order to evaluate the quenching process in the polymers.     

Fluorescent dyes for guest-host applications

The spectral properties of some fluorescent dyes (hicarboxilic acid derivatives) in isotropie solvents and nematic liquid crystals have been studied and the temperature of the nematic-isotropic phase transition for dye-liquid-crystal mixtures has been determined. It was found that the dyes investigated emit green light, are aligned well in nematic liquid crystals, have quite high fluorescence efficiency and do not destabilize the nematic phase of the host. They can therefore be utilized in ‘guest-host’ liquid crystal display devices.     

双羟基七甲川菁染料的合成及其光谱性能研究

通过分子设计,分别以2,3,3-三甲基吲哚和1,1,2-三甲基-1H-苯并[e]吲哚为原料,首先合成两种季铵盐,再分别同2-氯-1-甲酰-3-羟基亚甲基环己烯缩合,利用Suzuki-Miyaura反应实现染料中位C—C偶联,以超过70%的收率制备了4种带有活性羟基的七甲川菁染料。利用核磁和高分辨率质谱对染料结构进行了表征。以乙醇为溶剂,用紫外-可见光谱仪考察了染料的光谱性能。采用电流为13.4 A的高压氙灯为光源,考察了染料的光稳定性。探究了pH对染料颜色的影响,并尝试推论变色机理。结果表明,4种七甲川菁染料均在近红外区产生较强吸收,在无水乙醇中均具有良好的光稳定性。不同pH下,染料的光谱性能研究发现,七甲川菁染料吸收光谱受pH影响较大,在pH=5～7时,染料在近红外区有最佳吸收。     

Influence of acid dyes on the thermal behavior of nylon 66

To reveal the effect of acid dyes on the melt processing of recycled nylon 66, 17 acid dyes with different chemical structures were used to dye a nylon 66 yarn. The thermal stability of dyestuffs, the thermal degradation of the dyed nylon 66 during compression molding, and the melting and crystallization of the dyed nylon were investigated. During melt processing, most dyed nylon 66 changed color strength and color pattern. This is attributed to the migration and chemical reactions of dyestuffs. Acid dyes containing metal ions, such as C.I. Acid Black 60, C.I. Acid Red 186, C.I. Acid Yellow 151, and C.I. Acid Black 107, have severe impact on the thermal stability of nylon 66. The influence of metal complex acid dyes on the thermal stability of nylon 66 can be explained by a mechanism of acid-catalyzed nucleophilic acyl substitution. It was observed that the existence of acid dye in nylon 66 does not influence the melting temperature of nylon. However, some metal complex dyes reduce the crystallization temperature of molten nylon. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67: 371–382, 1998     

A next-generation wide color gamut WLED with improved spectral performance in phosphor composite functional solid

As is well known, a way to obtain a high color resolution and saturation of a liquid crystal display and thereby obtain a higher visual accuracy and comfort in the coming 5G era remains an urgent challenge. In the present study, a new type of phosphor composite material doped with Ln³⁺ ions provides a promising alternative to the color filters used in White light-emitting diodes (WLEDs), achieving a better performance regarding the realization of a wider color gamut. The advantages of this composite material are illustrated through an abundant phase and morphology analysis along with a discussion regarding the X-ray photoelectron spectroscopy of the valence bond of Ce ions, which maintain the luminescence properties of the phosphor while providing a stable and solid amorphous environment. An improved spectral performance was obtained through color filtering at 580 nm along with the regulating effects of red, green, and blue emissions according to the doped Ln³⁺ ions. Notably, we fabricated a high-performance WLED based on a Ln³⁺-doped PiG with a correlated color temperature of 5037 K, color rendering index of 72.8, and high color gamut of 91.97%, providing a new choice for the development of luminescence materials with a high color resolution and saturation.     

界面致稳型柔性胆甾相液晶显示器件的制备与性能

以镀有氧化锡铟的聚对苯二甲酸乙二酯（ITO-PET）薄膜为柔性电极,对电极导电表面进行处理,以间隔子控制器件厚度,采用灌注法制备了界面致稳型可挠性双稳态胆甾相液晶显示器件。利用接触角测试仪、显微镜和紫外-可见分光光度等分析胆甾相液晶显示器件的微观结构及光电特性。结果表明,表面处理涂层可与液晶分子作用并产生界面致稳效应;采用大小为6 μm的间隔子,当改性层溶液中间隔子质量分数为3%时,制备了有效面积为10×15 cm²的柔性双稳态液晶显示器件,测得饱和驱动电压为40 V,在550 nm的透过率为90%;最后通过刻蚀技术处理器件电极制备了字符显示器件。     

Fabrication of Ultrahigh‐Strength Polybenzimidazole Fibers via a Novel and Green Integrated Liquid Crystal Spinning Process

Herein, the first example of ultrahigh‐strength polybenzimidazole (PBI) fibers using a PBI solution in liquid crystal state is reported via a novel and green integrated spinning technology. Microwave‐assisted polycondensation is utilized to synthesize the polybenzimidazole/polyphosphoric acid liquid crystal spinning solution and pure water is employed as the coagulating and washing bath to afford a green fabrication process. The green integrated spinning technology is eco‐friendly, cheap, and conducive for the large‐scale production of PBI fibers. The as‐prepared PBI fibers display superb flame retardancy, and the outstanding thermal stability of PBI fiber enables it to preserve structural integrity at temperatures as high as 600 °C. More significantly, it prepared the ultrahigh‐strength of PBI fiber up to 0.91 GPa, which is two times than that of the reported PBI fibers, marking a significant breakthrough for the high‐performance PBI fibers.     

Preparation of thermally stable dyes derived from diketopyrrolopyrrole pigment by polymerisation with polyisocyanate binder

Four thermally stable and solvent soluble dyes were prepared from diketopyrrolopyrrole pigment via an N‐alkylation reaction. To improve the thermal stability of the dyes, a hydroxyl functional group that could react with blocked polyisocyanates was introduced into the dyes. The prepared dyes had absorption maxima near 500 nm, and the chromaticity diagrams of all synthesised dyes exhibited smaller x and y values than those of CI Pigment Red 254, indicating that the colour of the synthesised dyes was close to an orange shade. The dyes reacting with blocked polyisocyanates showed extremely high thermal stability compared with analogous dyes not reacting with polyisocyanates.     

Preparation of flexible and transparent SMA films by simple composite with MBS potential for negative birefringence compensator

The brittleness of poly(styrene maleic anhydride) (SMA) was improved by compositing with elastic poly(methyl methacrylate‐butadiene‐styrene) (MBS) to develop it into optical film. Transparent and flexible SMA films were prepared, and the flexibility of them was checked by folding endurance test and folding bend. The transparence of SMAMBS films were proved by the transmittance and haze measurements. In actual view, the letters could be clearly observed while they were covered by prepared films. The thermal stability of them was confirmed by DSC and TGA analysis. These physical properties of films are comparable to that of polycarbonate which is widely used as optical film. Besides of these, mechanical and fracture properties of them were found to be also suitable for this purpose. Furthermore, negative birefringence could be obtained by orientationally stretching them. Such results indicate that, films prepared from composites are competent for negative birefringence optical compensator in the field of liquid crystal display. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

A new manufacturable filter design approach for spectral reflectance estimation

Selection of the best possible filter set among a set of available filters is the obvious method of increasing dimension of camera signals for spectral reflectance reconstruction. There are also methods that are focusing on the filter design regardless of noticing to the constructability of the designed filters. This study shows that direct optimization of physical variables of filter manufacturing technique is more reliable than indirect approach of designing and then physical manufacturing of the designed filters. Direct optimization of the transmission‐controlling primaries in filter manufacturing process would guarantee having the designed filters in reality. Combination of some solvent dyes was used as the spectral transmission matching system for filter manufacturing. As a conventional technique, filters were designed and best possible dye concentrations that match the desired filters were calculated. As an alternative approach, filters were also designed using direct optimization of dyes concentrations. The results showed that direct optimization of dye concentrations exhibits better performance in comparison with the conventional technique. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 316–326, 2017     

高分子染料在纤维染色中的研究进展

在纤维染色中,染料可以分为反应性高分子染料,分散高分子染料及酸性高分子染料等。这些染料具有各自鲜明的染色性能特点,如反应性高分子染料可与纤维以共价键结合而染色,分散性高分子染料与纤维有很好的相容性,酸性高分子染料可与相应的单体染料具有相同的染色性能但热稳定性更好。本文介绍了各类高分子染料的结构特点及在纤维染色中的应用情况。有24篇参考文献。     

BODIPY荧光二向性液晶染料的制备及性能

以8-(4-碘苯基)氟硼吡咯为原料,与4-乙炔基苯基胆甾醇酯或4-乙炔基苯戊基双环己基甲醇酯进行Sonogashira偶联反应,制备了两个含氟的荧光二向性液晶染料DC-1和DC-2,其化学结构均由1HNMR、13CNMR和HRMS鉴定。将染料DC-1和DC-2进行光谱测试,最大吸收波长和最大发射波长分别在503和517 nm,发亮绿色荧光。基于宾-主(G-H)效应,将染料DC-1和DC-2作为宾体组分溶于主体液晶E7中,测得DC-2在液晶E7中的吸收二向色比高达8.91,有序参数为0.73,可应用在宾-主型液晶显示器(GH-LCD)中。经差热扫描量热仪(DSC)测试,染料DC-1和DC-2在一定温度范围内具有介晶性质,并通过偏光显微镜(POM)验证了DC-1和DC-2的液晶织构。     

Comparison of the performance of masterbatch and liquid color concentrates for mass coloration of polypropylene

The properties of polypropylene (PP) mixed with masterbatch (MB) and liquid color concentrates (LCC), respectively, were compared by preparing samples of PP with MB and PP with LCC and neat PP as a reference material using 1–4 extrusion cycles. Two colors were examined, i.e., a white color consisting of pigment white 6, and a green color consisting of pigment white 6, pigment blue 15:3, and pigment green 7. The color difference between PP prepared with MB and LCC was determined and the mechanical, rheological, and crystalline properties of PP prepared with MB and LCC were found to be generic. The color of PP obtained from MB and LCC were comparable. Further, it was found that the tensile strength, the viscosity, and the crystal structure obtained were similar when using LCC instead of MB. The viscosity of the treated PP generally decreased with increasing extruder retention time due to thermal degradation. The tensile strength and the crystal structure were independent of increased extruder retention time. © 2015 Wiley Periodicals, Inc. Col Res Appl, 41, 484–492, 2016     

Graphene oxide modified waterborne polyurethane-based dye with high color-fastness performance

Graphene oxide (GO) was incorporated into waterborne polyurethane-based polymeric dyes to prepare GO modified polymeric dyes for further improving the performances of waterborne polyurethane-based dyes. Structure properties of the prepared polymeric dyes were analyzed using FTIR and UV–Vis spectrophotometers. The fastnesses to dry-wet rubbing, thermal migration, light, and the mechanical properties of the GO modified polymeric dye films were further investigated. The introduction of GO might lower the tensile strength and the elongation at break of polymeric dye films. Meanwhile, the color of modified polymeric dye films turned to be darker as the GO dosage increased. Moreover, most of the above-mentioned properties could be enhanced considerably. In particular, the dry-wet rubbing and thermal migration fastness of modified polymeric dye films could be enhanced up to grade 5. This suggests that the GO modified waterborne polyurethane-based dye has the potential to be used in leather finishing coloring with high performance.     

Colorimetric characteristics of colored single-coat enamels

Compositions for single-coat glass enamels that allow obtaining a wide color range of coatings with sufficiently good surface quality for steel articles were developed. Different dyes were tested. Properties of the coatings such as the chemical stability, adhesive strength, gloss, and thermal stability were investigated and the firing temperature range, 670–740°C on average, was determined. The colorimetric characteristics of single-coat enamels were calculated. The enamel coatings obtained can be used in mass production.