瓦楞纸印刷与金属网纹辊

瓦楞纸印刷与金属网纹辊林逢铭使用金属网纹辊的传墨系统，配合柔性版和水性油墨，能大大提高瓦楞纸印刷质量。柔性版印刷属于轻压力印刷，也叫吻合印刷。印版与瓦楞纸只要轻轻接触，水性油墨就很快转移到纸版上，尤如用橡皮图章压力轻，硬质图章压力重。瓦楞低的地方也不...     

浅谈瓦楞纸板印刷用网纹辊

天津王朝包装印刷制品有限公司长期从事瓦楞纸板的图案印刷,但要获得高质量的印品,涉及的可变因素很多。设备、油墨、板材和工艺等的不断改进使今天的许多印刷原理必须服从于明天的变化。但有些问题是相对不变的,其中最主要的一点是提高印品质量,瓦楞纸版印刷机油墨网纹辊所具有的良好印刷特性是必不可少的。不过,在谈及瓦楞纸印刷用的网纹辊之前,我们应先对网纹辊作些解释。大多数网纹辊(或称传墨辊)所采用的表面有三种,即有刻纹的铬表面、有刻纹的陶瓷表面和有纹理的或称无规则墨孔的陶瓷表面。辊子镀铬或涂陶瓷之前要刻花,其机械加工方法…     

如何延长网纹辊的使用寿命

网纹辊是柔印中的核心部件,其对提高印刷质量的重要性已无须赘述。由于网纹辊是一种易损部件,并且价格不绯,因此在平时使用时,要加强对网纹辊的维护和保养。本文主要就如何延长网纹辊的寿命做一些探讨。正确使用网纹辊1、在开机印刷前,要综合考虑印版、油墨等的特点,选配合适的     

关于金属网纹辊的线数

在柔性版印刷机中与印版接触并传递油墨的这条辊就是金属网纹辊。金属网效辊在柔印机的传墨系统中是关键部分，亦是柔印机的心脏。它直接关系到印件的墨量；印刷网线图像时，亦关系到色彩的还原、层次和立体感。因此对金属网经辊的结构、作用、线数性能机理的了解，不但能恰如其分地选择好、用好金属网线辊，更主要是它关系到印刷的质量，我们研制金属网纹辊10多年，从实践中对它有些认识，谈些看法供大家参考。金属网纹辊的结构如图，它是在金属光辊上加工了无数的凹点，这些凹点的大小、形状、深浅都一致。在印刷上使用的金属网纹辊，用眼…     

如何用好柔印中的网纹辊

在柔版印刷中,网纹辊是印版传墨过程中最为精细的部分,网纹辊的运行状态对保持墨层稳定性和印品印刷质量都具有重要作用。     

如何利用网纹辊的改进技术

对于网纹辊来说，已经有了许多新的发展。但是，只有对印刷工艺进行基础调节，我们才能看到这种新的变化带来的好结果。柔性版印刷商都希望自己能够占有一定的优势。印刷机和配件生产商们也一直在宣扬其新技术改进的威力。但是如果我们不注意基础工作，所有这些新技术也不会带给我们想象的结果。下面我们来解释一下，什么是基础工作？也就是，系统在何种情况下需要进行精细的校调？－当使用橡皮夹紧辊（ｒｕｂｂｅｒｎｉｐｒｏｌｌ）来替代刮墨刀进行使用时，这种技术并不能精确地控制网纹辊上的墨层厚度。－当ＰＨ值或油墨粘性（两个影响油…     

如何利用网纹辊的改进技术

对于网纹辊来说，已经有了许多新的发展。但是，只有对印刷工艺进行基础调节，我们才能看到这种新的变化带来的好结果。柔性版印刷商都希望自己能够占有一定的优势。印刷机和配件生产商们也一直在宣扬其新技术改进的威力。但是如果我们不注意基础工作，所有这些新技术也不会带给我们想象的结果。下面我们来解释一下，什么是基础工作？也就是，系统在何种情况下需要进行精细的校调？－当使用橡皮夹紧辊（rubberniproll）来替代刮墨刀进行使用时，这种技术并不能精确地控制网纹辊上的墨层厚度。－当PH值或油墨粘性（两个影响油墨流动性的关键…     

如何用好柔印中的网纹辊

正在柔版印刷中,网纹辊是印版传墨过程中最为精细的部分,网纹辊的运行状态对保持墨层稳定性和印品印刷质量都具有重要作用。网纹辊辊面受损的原因及其解决方法网纹辊是将油墨传递到印版图文部分的核心部件,一旦辊面出现划伤,会严重影响印品的印刷质量。以下三个方面是导致网纹辊辊面受损的主要因素。采用封闭式刮墨刀比单刮刀刮墨和胶辊挤压更容易出现辊面划伤     

柔性版印刷中的环保措施

1 前言 目前,柔性版印刷已广泛用于多种包装印刷品,如烟包、医药包装、食品包装、商标标签印刷等,形成了一定的市场。据2002年数据统计,全国已有400多条机组式、卫星式生产线,其中瓦楞纸箱柔性版印刷发展最快。柔性版印刷有如下特点:承印材料广泛、操作简单、联机一次成型、低投入高产出、印品范围厂、采用短墨路传墨系统、经压力印刷和采用环保无污染水性油墨。柔性版印刷中的环保性已是不争的事实,但到底有何措施确保这种生产的环保性呢?本文针对柔性版印刷,总结了其中采用的种种环保措施。     

Technology Education and Developing Countries

This article considers the problem of introducing technology education as a school subject in development countries. Should the subject draw inspiration from everyday circumstances in these countries, or should it leapfrog to the space age? Answers depend upon circumstance. Alternative scenarios for how technology can be introduced in these settings are set forth. They include technology as reconstituted industrial arts, and technology across the curriculum.     

Technology Education and Developing Countries

This article considers the problem of introducing technology education as a school subject in development countries. Should the subject draw inspiration from everyday circumstances in these countries, or should it leapfrog to the space age? Answers depend upon circumstance. Alternative scenarios for how technology can be introduced in these settings are set forth. They include technology as reconstituted industrial arts, and technology across the curriculum. This revised version was published online in July 2006 with corrections to the Cover Date.     

大力发展火箭制造技术

<正>航天制造技术作为现代工程制造技术的重要组成部分,对国民经济的发展以及增强国防威慑能力具有极为重要的作用,是航天产品的性能、可靠性和成本的决定性因素之一。     

发展创新文化促进科技创新

中国的创新战略激励着中国企业作为创新主体登上新一轮创新舞台,纷纷投入创新的热潮。企业也在以各种方式开拓自己的创新之路时,但却有许多外国的业界人士不断地提出质疑。电子产     

Factors that Influence Children's Developing Perceptions of Technology

Two instruments designed to ascertain children's conceptions of ‘technology’ were given to 315 English children in Years 2–6. A subset of 81 children and their teachers were interviewed. Responses to the same instruments were collected from 745 Western Australian children in the same year groups. Subsequently their teachers and 164 Australian children were interviewed. The Australian and English children had a similar range of concepts to explain technology, but the frequency of concepts varied. The results suggest that the stages of developing an inclusive concept of technology are mainly chronological, but the rates vary with individuals depending on a number of inter-related factors including home and school influence, ability, gender and opportunity to discuss ideas. Examination of these factors suggests there is a need for specific curriculum provision in technology based on adequate in- service training of teachers, which should also clarify the differences between science and technology. Children also need to be enabled to clarify their ideas through focused activities. This revised version was published online in August 2006 with corrections to the Cover Date.     

发展高效发电技术的战略选择

超临界和超超临界发电技术简介工程热力学定义水的临界状态点压力为22.115兆帕、温度为374.15℃,当达到临界点状态参数时,不再存在汽、水二相区,水直接从液态变成气态。如果水蒸气参数大于临界状态点参数,则称为超临界,相反则称为亚临界。蒸汽的高参数意味着发电效率的提高。超     

Developing Technological Stance: Children's Learning in Technology Education

Following a review of current research in children's learning in technology education, and an examination of the kinds of knowledge demanded in contemporary technology education programs in elementary schools, I argue that what is needed in early technology education programs is the scaffolding of what I am calling technological stance. This construct acknowledges the socio-cultural character of technology as a human endeavor. In contrast to programs which are oriented to application of conceptual and procedural knowledge or to programs in which knowledge is generated through interpretation of interactions with materials and tools, programs which support technological stance position learners as critical inquirers into both tool-related and discursive practices of technology.