水性油墨用新型乳液设计合成及构效关系

A large proportion of food packaging is printed using solvent-based ink systems. Solvent-based inks primarily contain alcohols and esters as volatile organic compounds (VOC) with concentration ranging from 50% to 70% at print viscosity. As a result of drying processes a VOCs will be released to the air circulating in the dryer and without treatment .The solvents are not evaporated completely，some amount is retained in the ink and being released slowly, which is an inherent health problem and has negative effects in the perception of aroma and taste of the food contents of the package. Therefore, there is a growing demand to make use of water based inks. But water-based inks still have some problems. One of the main problems is the slower absorption of water based inks into the substrate, as well as poor wetting properties on non-absorbent substrates,that is because the higher surface tension of water. Wet rub resistance tends to be poor when printing with water-based inks on polymeric substrates, which may be related to the fundamental difficulty of achieving good wetting of these surfaces. A longer time is required for the inks to dry using water-based inks in packaging of non-hygroscopic substrates printing. Emulsion is a key component when selecting the resin to be used in the water-based ink. The emulsion polymers have lower polarity which gives a faster water release than with acrylic solutions and improved drying speed. The aim of this study is to overcome the above mentioned drying and adhering problems of the water based ink in packaging printing. To achieve this target we have done through material design, particle design, size design, design and synthesis of molecular weight with a low surface tension emultion of core shell copolymer and hyperbranched emulsion will be synthetize for water-based ink. The characterization of microstructure of the synthesized latex ,thermodynamic properties, particle size and distribution, size and molecular weight distribution and interfacial tension are measurand using SEM, TEM, IR, NMR, DSC , particle size analyzer, gel permeation chromatography GPC, interfacial tension meter. Study the relationship molecular characteristics and emulsion polymerization process and the curing of the relationship,to be obtained emulsion with good adhesion and fast drying for water-based ink in the non-polar materials attached and.The purpose of the present project is to analyse and understand the performance of a family of water-based acrylic printed on different polymer-coated boards Several print quality parameters are evaluated，correlations between these and ink rheology, surface tension in the wet state, and surface energy in the dry state before and after printing will be investigated. The results will provide innovative ideas and theoretical foundation for water-based printed on polymer-coated boards film for food packaging.

随着全球环保意识增强和生活水平提高，节能减排和食品包装安全成为众所关注的问题。食品包装大多为薄膜材料，使用溶剂型油墨进行印刷，存在污染大气和溶剂残留量高的缺点。水性油墨以水做溶剂，在安全和环保方面具有不可替代的优势，但在聚合物基材料表面印刷时出现附着性差和干燥慢问题。从水性油墨关键组分乳液入手，设计和制备新型乳液并研究其在食品包装薄膜的润湿和干燥，有可能解决上述问题。本项目从界面化学的角度设计乳液，通过粒子和粒径设计、分子量设计等合成出核壳结构低表面张力乳液，利用扫描电镜、透射电镜、红外光谱仪、核磁共振仪、示差扫描量热仪、粒度分析仪、凝胶渗透色谱仪、表面张力仪等手段表征乳液的微观结构、热力学性能、粒径、分子量和表面张力，探讨乳液的分子特性与食品薄膜材料上附着和干燥的关系，研究水性油墨在薄膜材料上的干燥机理。本项目研究成果对阐明水性油墨在非极性材料的表面润湿和干燥机制具有理论意义和应用前景。

随着国家对空气污染治理步伐的加大，水性油墨作为一种以水为主要溶剂的环保油墨成为印刷企业进行结构升级的首选材料之一，但承印在塑料薄膜上的凹印水墨与柔印水墨受到干燥速度及附着力的影响而不能得到很好的应用。本项目以新型乳胶为研究对象，对其在水墨乳液中的构效关系进行研究。具体内容主要制备了低表面张力核壳结构改性丙烯酸酯乳液，研究了单体组成、乳化剂种类以及制备工艺对乳液粒径大小及分布、吸水率、附着力和干燥性设等影响，研究了多相体系中组分相容性的影响因素，设计制备的乳液在几种薄膜上具有很好的附着力和干燥性。得到影响附着力和干燥性的关键因素，对于水性油墨在薄膜食品包装上的进一步推广应用有重要意义。解决乳液在非吸附薄膜上的干燥性和附着力问题，并重新研究其基础理论与基本技术。