铜版纸湿拉毛和湿排斥性能的研究

利用IGT印刷适性仪模拟实际印刷,以铜版纸为纸样,通过改变印刷速度和润版液供给量等印刷条件,考察了3种纸样所产生的湿拉毛和湿排斥效果.结果表明,铜版纸湿拉毛和湿排斥的性能受印刷速度的影响更大.印刷速度越高,铜版纸湿拉毛倾向越小,湿排斥倾向则越明显.另外,铜版纸的优良涂布结构使得其纵横向的湿拉毛和湿排斥性能差别不大.     

平版印刷中润版液的检测与分析

主要介绍把平版印刷的润版液参数要求及其在印刷过程中的作用,以及检测的方法.并重点分析了润版液的主要成分和添加剂在润版液中所起的作用以及对印刷的影响.     

合理管理润版液提高马口铁印刷质量

马口铁印刷属于使用润版液的平板橡皮印刷工艺，需要在油墨和润版液之间保持一个标准的平衡关系，正确管理使用润版液，可以获得稳定的印刷质量、提高印铁机的开工率。     

润版液在胶印印刷中的功能和作用

胶印是当今主要的印刷方式,印版版面影像部分和非影像部分高度相差极小,只有2微米左右,印刷过程就是水墨平衡的过程;在胶印印刷中,润版液承担版面空白部分不被油墨污染的作用。润版液分三大类:酸性润版液,醇性润版液和非离子表面活性润版液;目前最常用的是醇类润版液,其主要成分有水、电解质、缓冲剂、印版保护剂、表面活性剂、杀菌防霉剂、络合剂、醇类物质、金属清洗剂、阿拉伯树胶等。本文详细介绍润版液的组成、作用和控制相关工艺参数的方法。     

高速轮转胶印润版液的应用研究

阐述了高速轮转胶印润版液的组成,保持润版液与油墨的相对稳定,及达到印刷所要求水墨平衡的方法,提出了在高速轮转印刷中,为确保图文信息的良好再现,对润版液的正确应用和相关控制要素,具有实际应用价值.     

水的硬度对乳化油墨印刷适性的影响

探讨了胶印润版液中水的硬度对乳化之后油墨的粘着性、印刷网点扩大值和色域等影响的基本规律,为润版液配制时水的硬度确定提供了实验参考和理论数据.     

湿平整液应用与分析

本文介绍了干、湿平整轧制的不同性能,湿平整液系统组成和应用,通过平整轧制过程中主要参数计算分析,得出在湿平整轧制生产过程中,湿平整液可以降低平整机的功率损失和轧制压力损失,提高带材板形质量。     

谈谈胶印印刷用的润版液

胶版印刷，即平面印刷，其印版上需印刷的图文部分和空白部分都处于印版的同一平面上，利用水、墨平衡的原理实施印刷作业。实际印刷时，印版上不但要不断地沾补新的印墨，而且要不断注补新的润版液，在印版的空白部分保持良好的亲水性，防止油墨向空白部分扩散，保证印刷时印版上的水、墨平衡，达到良好的印刷质量。本文系统地介绍此印版润版液的作用、成分、功能、特性和实际应用时的注意事项，并列举市场上常见的润版液产品的品牌和性能特点。     

轮转印刷中水墨平衡控制浅析

商业轮转印刷机是近几年从国外引进的高速高品质印刷机。它具有印刷速度快(有的机速达60000张/小时)、印刷版面多、质量稳定、时效性强等突出优点,与单张纸机有许多共同的地方,但更有许多不同之处,如:输纸机构,印刷速度,印刷所用纸张,油墨干燥方式,折页方式,质量标准,纸张损耗等。所以我们要熟练掌握它还需要一个过程。大家都知道目前与印刷质量密切相关的因素有很多,但最难控制的可能就是印刷的水墨平衡问题了。胶印水墨平衡是指在一定的印刷速度和印刷压力下,调节润版液的供给量,使乳化后的油墨所含润版液的比例小于26%,形成轻微的W/O型…     

PP棉滤芯与胶印润版液过滤级数的关系

目的研究PP棉滤芯对胶印润版液的过滤净化性能,在满足过滤要求的前提下,为胶印机润版液过滤系统选择合理的过滤级数。方法设置四级润版液过滤净化系统,以0.5,1μm孔径的PP棉滤芯作为过滤介质,测量润版液经过每级过滤前后的p H值、电导率和表面张力。结果以孔径1μm的PP棉滤芯作为一级过滤,0.5μm的PP棉滤芯为二级、三级、四级过滤滤芯,经过第4级过滤后,润版液核心参数处于印刷要求范围内,但变化率不足1%。结论此类胶印润版液过滤装置最优过滤级数为三级过滤。     

Prospective Validation of High-Shear Wet Granulation Process by Wet Granule Sieving Method. II. Utility of Wet Granule Sieving Method

The general utility of a method for determination of high-shear wet granulation end point by monitoring the wet granule particle size distribution was evaluated. Wet granulation was conducted in a 25-liter high-shear mixer using four model drugs with different solubilities and particle sizes (ethenzamide, unmilled and milled acetaminophen, and antipyrine). For each drug formulation, its wet granule particle size fraction and target range for granulation end point determination were selected based on the tablet characteristics that are known to be influenced by the wet granulation process. Granules manufactured under different conditions (i.e., different main and chopper blade speeds and binder supplying rate) but manufactured to the same granulation end point determined by the selected fraction and range showed very similar granule characteristics and subsequently very similar tabler characteristics. From the fact that there was a good correlation between the wet and dry-sized granule particle size distributions even if the drying method was changed from fluid-bed drying to vacuum drying, the general application of the end point determining method was verified. Further, the method was shown to be sensitive to the critical granulation parameters for granulation progression and to be very capable of determining the granulation extent. Thus, it was suggested that the method is applicable to various drugs and formulations for determination of wet granulation end point.     

To Wet or Not to Wet: That Is the Question

Wetting transitions have been predicted and observed to occur for various combinations of fluids and surfaces. This paper describes the origin of such transitions, for liquid films on solid surfaces, in terms of the gas-surface interaction potentials V(r), which depend on the specific adsorption system. The transitions of light inert gases and H₂ molecules on alkali metal surfaces have been explored extensively and are relatively well understood in terms of the least attractive adsorption interactions in nature. Much less thoroughly investigated are wetting transitions of Hg, H₂O, heavy inert gases and other molecular films. The basic idea is that nonwetting occurs, for energetic reasons, if the adsorption potential’s well-depth D is smaller than, or comparable to, the well-depth ε of the adsorbate-adsorbate mutual interaction. At the wetting temperature, T _w, the transition to wetting occurs, for entropic reasons, when the liquid’s surface tension is sufficiently small that the free energy cost in forming a thick film is sufficiently compensated by the fluid-surface interaction energy. Guidelines useful for exploring wetting transitions of other systems are analyzed, in terms of generic criteria involving the “simple model”, which yields results in terms of gas-surface interaction parameters and thermodynamic properties of the bulk adsorbate.     

划伤缩微品的湿法复印

复印时,在划伤的缩微品上涂布四氯乙烯等适当液体,可以得到清晰度良好的硬拷贝。本文讨论了湿法复印的基本原理,并报导了试验的方法和结果。本文还讨论了其他有关湿法复印的技术问题。     

Topological Adhesion of Wet Materials

Achieving strong adhesion between wet materials (i.e., tissues and hydrogels) is challenging. Existing adhesives are weak, toxic, incompatible with wet and soft surfaces, or restricted to specific functional groups from the wet materials. The approach reported here uses biocompatible polymer chains to achieve strong adhesion and retain softness, but requires no functional groups from the wet materials. In response to a trigger, the polymer chains form a network, in topological entanglement with the two polymer networks of the wet materials, stitching them together like a suture at the molecular scale. To illustrate topological adhesion, pH is used as a trigger. The stitching polymers are soluble in water in one pH range but form a polymer network in another pH range. Several stitching polymers are selected to create strong adhesion between hydrogels in full range of pH, as well as between hydrogels and various porcine tissues (liver, heart, artery, skin, and stomach). The adhesion energy above 1000 J m^?2 is achieved when the stitching polymer network elicits the hysteresis in the wet materials. The molecular suture can be designed to be permanent, transient, or removable on‐demand. The topological adhesion may open many opportunities in complex and diverse environments.     

ABS塑料件多层"湿碰湿"涂装新工艺

对ABS塑料多层涂装工艺进行了探讨,指出采用"湿碰湿"工艺可提高生产效率和产品合格率,涂层各项性能指标合格.     

Carboxymethylstarches in Wet Granulation

Abstract

Commercialized carboxymethystarches (CMS) are both carboxyme-thylated and cross linked potato starch.

The influence of carboxymethylation and cross linkage on the disintegrating properties of starch are studied.

Tablets are made with acetaminophen as drug, Emcompress as diluant, Magnesium stearat as lubricant, and potato starch or its derivatives as disintegrants.

Tablets are prepared by direct compression or by wet granulation with the disintegrant intervening only in internal phasis.

Five disintegrants were studied, with two different concentrations:

native potato starch

potato starch simply cross linked

potato starch simply carboxymethylated

two potato starches both cross linked and carboxymethylated at two different degrees

Compressibility of powders blending and grain for compression are discussed.

The hardness, the tablet disintegration and the rate of drug dissolution are studied.

The results showed that the simply carboxymethylated starch has a totally different behaviour after direct compression or wet granulation. The poor results after wet granulation could be imputed to the bursting of starch granules during grain drying. Since it has lost its granular structure, the carboxymethylated starch will only allow a poor disintegration and a slow dissolution of the drug.

A very similar behaviour of native and simply cross linked starch: the results of which are bad for tablets either prepared by wet granulation or direct compression.

A very similar behaviour of the starches both carboxymethylated and cross linked, allowing a very good disponibility, either with tablets prepared by direct compression or wet granulation. These experiments prove :

the need for an sufficient cross linkage for CMS in a wet granulation process     

Carboxymethylstarches in Wet Granulation

Commercialized carboxymethystarches (CMS) are both carboxyme-thylated and cross linked potato starch.

The influence of carboxymethylation and cross linkage on the disintegrating properties of starch are studied.

Tablets are made with acetaminophen as drug, Emcompress as diluant, Magnesium stearat as lubricant, and potato starch or its derivatives as disintegrants.

Tablets are prepared by direct compression or by wet granulation with the disintegrant intervening only in internal phasis.

Five disintegrants were studied, with two different concentrations:

native potato starch

potato starch simply cross linked

potato starch simply carboxymethylated

two potato starches both cross linked and carboxymethylated at two different degrees

Compressibility of powders blending and grain for compression are discussed.

The hardness, the tablet disintegration and the rate of drug dissolution are studied.

The results showed that the simply carboxymethylated starch has a totally different behaviour after direct compression or wet granulation. The poor results after wet granulation could be imputed to the bursting of starch granules during grain drying. Since it has lost its granular structure, the carboxymethylated starch will only allow a poor disintegration and a slow dissolution of the drug.

A very similar behaviour of native and simply cross linked starch: the results of which are bad for tablets either prepared by wet granulation or direct compression.

A very similar behaviour of the starches both carboxymethylated and cross linked, allowing a very good disponibility, either with tablets prepared by direct compression or wet granulation. These experiments prove :

the need for an sufficient cross linkage for CMS in a wet granulation process     

Prospective Validation of High-Shear Wet Granulation Process by Wet Granule Sieving Method. I. Selection and Characterization of Sieving Parameters for Wet Granules

To characterize the progression of high-shear wet granulation for various drugs and formulations based on the particle size distribution of wet granules during granulation, a general sieving method for wet granules was investigated. Wet granulation was conducted in a 25-liter high-shear mixer using four model drugs with different solubilities and particle sizes (ethenzamide, unmilled and milled acetaminophen, and antipyrine). Because of its small size and efficient sifting mechanism, a sonic sifter was used to determine the wet granulation particle size distribution. From the good correlation of particle size distribution between wet granules and dry-sized granules, an intensity of 80% of full-scale amplitude and a sieving time of 3 min were selected as wet granule sieving parameters. 7% general sieving method showed good measurement precision as long as the determination was completed within 20 min after sampling, Further, the method was independent of sampling position within the mixer chamber.