UV油墨固化窗口的探索

UV油墨固化的基本条件就是在一定的紫外光照射下激活油墨配方中的光引发剂生成自由基,进而引发整个油墨的化学反应实现油墨固化。UV油墨组成中含有的连接料、颜料、助剂、引发剂等成分都会竞争吸收紫外光,因此探索设计一个紫外光可以最大程度被光引发剂吸收的窗口是实现UV油墨高效固化的关键。     

华光YP-U型UV油墨印刷用PS版

UV油墨,亦称紫外油墨.UV油墨是将颜料分散到由预聚体、单体和光引发剂等物质组成的成膜物中,印刷时利用紫外线照射使油墨成膜并干燥. 在紫外光的照射下,UV油墨中的光聚合引发剂吸收一定波长的光子,激发到激发状态形成自由基或离子,再通过分子间能量的传递,使聚合性预聚体和感光络合体不断交联聚合固化成膜.     

印刷UV油墨的成分及性能

紫外光(UV)固化油墨是目前在印刷行业中被认为是环保、绿色、可持续发展的油墨。它具有很多的优越性,是未来油墨发展的大趋势,正被越来越多的印刷企业所使用。UV油墨的主要成分有光引发剂、单体、预聚物、颜料、稳定剂和其他助剂,主要对这些成分做简要介绍,然后简要探讨UV油墨品质的主要性能。     

复合光引发剂对UV油墨固化速度影响的研究

选用了 6种光引发剂进行复合配制黑色丝印UV油墨 ,实验结果表明 ,用复合光引发剂比用单一光引发剂配制UV油墨的固化速度快 ;在复合光引发剂中 ,应选择吸收光谱与颜料的吸收光谱相匹配的光引发剂 ,以及吸收光谱与光源发出的主波长较一致的光引发剂 ;另外 ,油墨中复合光引发剂含量应适量 ,这些对提高UV油墨的固化速度都有很大的帮助。     

光固化UV防金属皱纹（皮纹）油墨的研制与应用

紫外光固化UV防金属皱纹（皮纹）油墨,是由聚氨酯丙烯酸树脂、环氧丙烯酸树脂、稀释剂、光引发剂及其他助剂为原料制造而成。该产品是丝网印恻的特种装饰装油墨,可广泛应用于包装印刷领域,提高产品的包装档次,使产品增值增色。     

不同颜色体系的UV丝印油墨中光引发体系的选择

使用紫外-可见分光光度计测得了黄、蓝、橙、紫4种颜料的紫外吸收图谱;在模型化的丝印油墨配方中改变光引发剂的种类,运用指压法和指抠法研究了多种光引发剂对含有这4种颜料的UV油墨的引发速度的影响。结果表明不同颜色的颜料对紫外光的吸收区域和吸收强度是不同的。对于黄色油墨,907的引发效果最佳;对于蓝色油墨,907+ITX+EDAB和910+ITX+EDAB都具有很高的引发速度;而对于橙色油墨和紫色油墨,907+ITX+EDAB则是速度最高的引发剂组合。     

光引发剂对数码喷墨用黑色UV固化油墨固化速率的影响

选用7种光引发剂配制数码喷墨用黑色UV固化油墨,实验结果表明,使用光引发剂2022的固化 速率最快;当光引发剂与胺促进剂复配时,UV固化油墨的固化速率有较大提高。     

UV光固化涂料及其研究进展

介绍了UV光固化涂料的特点及固化机理,并对紫外光固化涂料中的光引发剂、活性单体、低聚物等方面进行了综述。详细介绍了紫外光固化涂料的主要品种,包括UV光固化油性涂料、UV光固化水性涂料、UV光固化粉末涂料阐述了紫外光固化涂料的研究进展。     

UV自由基固化和阳离子固化油墨的比较试验

根据固化机理,UV固化油墨主要有自由基型和阳离子型两种。对自由基固化和阳离子固化油墨进行了对照试验,进行了自由基光引发剂的筛选,并考察了两者固化涂层的性能、温度对固化速度的影响及作为UV固化油墨的优缺点,并从理论上进行了分析。     

UV光固化炸药油墨的研究现状

本文介绍UV光固化的固化机理,井对光固化剂组成中的光引发剂的分类、活性低聚物等方面进行综述.详细介绍了UV光固化炸药油墨的应用及其在国内外的研究进展     

UV油墨的制备与性能优化

探讨了预聚物、单体、光引发剂、颜料等组分对UV油墨固化速度、附着力、耐抗性等性能的影响,应用正交实验设计方法对UV油墨各组分种类进行选择,对正交试验结果做极差分析及方差分析,结果表明：根据预先设计的组分比例,采用预聚物PQ611,单体A,光引发剂B,活性氨为加速剂,获得性能较好的UV油墨。     

3D打印用长波紫外光固化树脂的制备

通过优化引发剂的种类和用量,得到一系列阳离子和自由基混杂体系光固化树脂,并用旋转流变仪和SLA型3D打印机进行长波紫外光固化和3D打印成型。结果表明:与芳基鎓盐类阳离子光引发剂PAG202相比,芳茂铁盐类阳离子光引发剂261具有长波紫外光固化的适应性,而光敏增感剂PAS-50对光引发剂261敏化显著,在长波紫外光下光引发剂261/PAS-50体系能快速引发树脂固化。最佳配方时,固化树脂的弯曲模量高于国内外同类树脂的,且具有较低的固化收缩率。     

Preliminary study on the utilization of lignin as filler in ultra‐violet (UV) curable system

In this study, Alcell lignin was used as filler in aliphatic urethane acrylate ultra violet (UV) curable resin system. The coating system was UV cured in the presence of free radical photoinitiator and cationic photoinitiator. The results showed that those with free radical photoinitiator produced coating film with higher degree of curing than those with cationic photoinitiator. The result of iodine number determination also showed that the unsaturated groups present in the UV curable system had reduced. This indicated that radical polymerization had taken place in the curing process of UV curable resin incorporated with lignin. In addition, the lignin content did not influence the curing process of the coating film. As for the coating film, it showed that the mechanical properties of the film were significantly influenced by the lignin content. This phenomenon was contributed by inherent stiffness of the lignin. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

The effect of different radiation sources for the UV curing of a screen‐printed,water‐based polyurethane acrylate binder

In this paper, titanium‐dioxide‐pigmented printing pastes of water‐borne, UV‐curable polyurethane acrylate binder with two different UV‐curing photoinitiator combinations were prepared and screen printed on a black t‐shirt fabric. The effects of mercury and gallium radiation sources employed either singly or in combination for UV curing and the total energy level on the printing performance were investigated. The cured textile samples were subjected to colour measurements before and after five cycles of washing, and hiding power and changes in chromacity, hue, and colour were determined. Single‐lamp applications of mercury and gallium were not satisfactory, and opaque pigment hindered deep curing, especially at thicker coating levels. It was found that employment of a mercury–gallium lamp system applying an irradiation at medium level can provide pigment printing of opaque white inks with excellent coverage, washing resistance, and medium hardness.     

Exergy and exergoeconomic analyses for integration of aromatics separation with aromatics upgrading

Methanol to aromatics produces multiple products, resulting in a limited selectivity of xylene. Aromatics upgrading is an effective way to produce more valuable xylene product, and different feed ratios generate discrepant product distributions. This work integrates the aromatics separation with toluene disproportionation, transalkylation of toluene and trimethylbenzene, and isomerization of xylene and trimethylbenzene. Exergy and exergoeconomic analyses are conducted to give insights in the splitting ratios of benzene, toluene and heavy aromatics for aromatics upgrading. First, a detailed simulation model is developed in Aspen HYSYS. Then, 300 splitting ratio sets of benzene and toluene for conversion are studied to investigate the process performances. The results indicate that there are different preferences for the splitting ratios of benzene and toluene in terms of exergy and exergoeconomic performances. The process generates lower total exergy destruction when the splitting ratio of toluene varies between 0.07 and 0.18, and that of benzene fluctuates between 0.55 and 0.6. Nevertheless, the process presents lower total product unit cost with the splitting ratio of toluene less than 0.18 and that of benzene fluctuating between 0.44 and 0.89. Besides, it is found that distillation is the biggest contributor to the total exergy destruction, accounting for 94.97%.     

Photocrosslinking of functionalized rubbers. X. Butadiene–acrylonitrile copolymers

The photocrosslinking of polyacrylonitrile‐block‐polybutadiene‐block‐polyacrylonitrile (ABA) was shown to proceed within seconds at ambient temperature upon UV exposure in the presence of an acylphosphine oxide photoinitiator. The curing process was followed by infrared spectroscopy, insolubilization, and hardness measurements. Complete insolubilization could not be achieved with the neat ABA rubber because of the poor reactivity of the 2‐butene double bond and the low vinyl content of the polybutadiene chain. The addition of multifunctional acrylate monomers (20 wt %) causes a substantial increase of both the reaction rate and the crosslink density of the polymer, which becomes completely insoluble in toluene in less than 1 s upon UV irradiation. An even greater effect was observed by using small amounts (1 wt %) of a trifunctional thiol crosslinker. Both the thiol and the photoinitiator concentrations were shown to affect the kinetics of the thiol–ene polymerization and the polymer network crosslink density. A direct relationship was found to exist between the swelling degree of the UV‐cured rubber and the interchain molecular weight of the network. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2204–2216, 2001     

Preparation and mechanism of free-radical/cationic hybrid photosensitive resin with high tensile strength for three-dimensional printing applications

A ultraviolet (UV)-curing free-radical/cationic hybrid resin is designed and developed by blending epoxy resin with an acrylic resin, including N-acryloyl morpholine, polyurethane acrylic ester (PUA), free-radical and cationic photoinitiator. During UV-curing, crosslinking locks the acrylate and epoxide polymers together through non-covalent interaction. Most likely, the interpenetrating polymer network (IPN) structure can be generated in the three-dimensional (3D)-printed objects. The obtained results from Fourier transform infrared spectroscopy (FT-IR) show that bisphenol A epoxy resin and acrylic resin are both successfully involved in the UV-curing process. In addition, the effects of the mass ratio of epoxy to acrylic resin and the UV irradiation time on the properties of the hybrid resin are systematically investigated using liquid crystal display (LCD) 3D printers. It is found that the tensile strength of the hybrid resin increases in a certain range and the elongation at the break maintains an upward trend with the increasing mass ratio. Finally, it is found that the shrinkage of the hybrid resin also depends on the mass ratio of epoxy to acrylic resin, which decreases with the increase of the epoxy resin content in a certain range. Thus, herein we propose a feasible UV-curing mechanism for the synthesis of hybrid resins for 3D printing applications.     

Synthesis and characterization of palm‐based resin for UV coating

The production of UV curable acrylated polyol ester prepolymer from palm oil and its downstream products offer potential and promising materials for applications such as polymeric film preparation and coatings. In this study, palm olein polyol was reacted with acrylic acid in the presence of a catalyst and inhibitors via condensation esterification process. The reaction temperature of 80°C and the stirring rate of 400 rpm produce a homogeneous product. Based on iodine value result, the suitable amount of p‐toluene sulfonic acid monohydrate used as catalyst was 3.0% (w/w) of palm olein polyol. Different UV curable formulations have been investigated using the synthesized prepolymers with monomers and a small amount of photoinitiator. Monomers used were 1,6‐hexanediol diacrylate (HDDA) and trimethylolpropane triacrylate (TMPTA) while photoinitiator used was 1‐hydroxy cyclohexyl phenylketone (Irgacure 184). The mixtures were cured to make thin polymeric films under UV radiation with doses between 2 and 14 passes (energy per pass is 0.6 J/cm²). Coating and curing was carried out on glass for pendulum hardness and FTIR analysis. Pendulum hardness of the film prepared using monomer HDDA and the prepolymer previously synthesized using 3.0% catalyst was 24.5%. The radiation dose needed was 14 passes. The highest pendulum hardness of 49.4% was achieved using monomer TMPTA and the prepolymer synthesized using 2.0% catalyst. The radiation dose needed was 10 passes. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

丁腈橡胶／丙烯酸酯UV固化压敏胶的研究

将丁腈橡胶溶于丙烯酸酯类混合单体中制成胶液，在常温下涂布于基材后进行紫外光辐照制备压敏胶带。采用红外光谱对UV辐照下的聚合过程进行了扫描分析并提出了固化机理。研究了光引发剂、UV辐照剂量、体系组成等对压敏胶带综合性能的影响。     

Synthesis and photopolymerization characterization of a novel difunctional photoinitiator

A novel difunctional photoinitiator HBP‐TDI‐HBP based on 4‐hydroxybenzophenone (HBP) and toluene‐2,4‐diisocyanate (TDI) was synthesized and characterized by ¹H NMR and UV–Vis absorption spectroscopy. The kinetics of photopolymerization was studied by real‐time infrared spectroscopy. It showed that HBP‐TDI‐HBP was a more effective photoinitiator than benzophenone. When this photointiator and amine were used to efficiently initiate polymerization of acrylates and methacrylates, both rate of polymerization and final conversion increased with increase of HBP‐TDI‐HBP concentration, light intensity, and amine concentration. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008