Earticle

Printed mottle of coated paper is one of the most common phenomenon and the most difficult problem in offset printing. Off-set printing is processed mainly processed by the attractive properties between water and oil, so all inks for off-printing must work with dampening solution(water). It may cause the emulsion on the printing nip from the printing pressure. This study aimed to investigate the effect of emulsified inks on print mottle from emulsified cyan ink by force with each different IPA contents. We measured the print mottle by densitometer and image analysis method. The emulsified inks also give effect to flow properties of inks and it caused more ink transfer rate, however, it caused low density of inks. Moreover the emulsified inks were spreaded to around of dots and cause the thinning density on the non-printing area like print mottle. The results showed that the emulsified inks also cause scumming on the printing result with little mistake of adjusting dampening solution and mostly decreasing dot reproduction. So we could find out the obvious effect of emulsified inks to print mottle.

Studies were carried out the phenomenal observation on the effect of corona treated hotmelt laminating film in process of manufacture by 2 kinds of experiments. These are as follow: 1) In order to verify the treatment reducing value of dynes and dynes durability with the lapse of time, it was checked dynes of a pair of 4 bar discharge electrode with 9 one for 144 hr., and it show results that 9 bar discharge electrode has higher initial dynes as well as keep up 48 dynes durability long than 4 one. 2) Drawn an inference from 3 actions -Chemical-Physical-Mechanical, on laminating film in terms of SEM's observation that are the adhesive status in boundary of corona treated base film, extrusion coating hotmelt layer, and configuration of hotmelt surface after corona treated. In tandem system, EVA layers adhesion keep its stability without corona discharge treatment.

The functional dyes, which has various optical characteristics that can be applicable to field of electronic, photo electronic, such as sensor or electrode, were synthesized. Physical property and optical stability was studied with preparation of conductive type film as a kind of optical filter of plasma display panel, by adapting neon cut off dye, which can selectively absorbing between 580 and 610nm wavelength. The filter was prepared with PSA resin, which has functional group of –COOH and –OH, as binder. And the characters such as spectroscopy, heat-proof / wet-proof, thermal stability and commerciality, which must be held by functional dyes, were examined. Conductive type film is the kind of film includes only neon cut off dyes. For the neon cut off dyes, cyanine dyes can be applied. And it is observed that spectrum of before and after the durability test are not changed due to stability of dyes, as the result of coating on the mesh film with PSA binder.

We have manufactured a photoresist which has excellent dispersity and good applying property due to 330 cps of viscosity for environment-friendly and economical maskless screen plate making. And the photoresist applied on the screen stretched was exposed with mask by UV-LED light source so we could manufacture the photoresist which proper for the UV light source. And it was developed by air spray with 1.7 kgf/㎠ of injection pressure. Because of the excellence of power and resolution of the UV-LED light sourse, the pencil hardness and solvent resistance of curing photoresist film were excellent as those of conventional photoresist film. Moreover the 100㎛-width stripe image which has sharp edges was formed. So we confirmed a possibility of dry development process by air spray method.

We designed a UV-LED exposure system which has 365nm dominant wavelength due to the environment-friendly and economical maskless screen plate making. And the photoresist applied on the screen stretched was exposed without mask by beam projector with UV-LED light source. Then it was developed by air spray with 1.7 kgf/㎠ of injection pressure. The pencil hardness and solvent resistance of curing photoresist film were excellent as those of conventional photoresist film and the maximum resolution of line image formed by maskless screen plate making. was 100㎛, so we could establish the possibility of environment-friendly maskless screen plate making technology. But the sharpness of the patterns were ±40㎛ since the exposure system for maskless plate making has weak light intensity and the diffusion of light.

The color reproduction of digital still camera does not, in general, match those of the final prints. Because color gamut of these devices is different, it is therefore necessary to take account of a way to match. The way uses the optimized profile to print an image. This paper proposed a way to create the input profile of digital still camera for standardization printing process. The results of proposed way showed that for input profiles equivalent, good results relatively. In this paper, an experiment was done where the illumination sources used as the standard illumination 5200K and illuminated at a 45° angle in the best illumination efficiently. The white balance was in mode 'custom':aperture F11, exposure time 1/60s, ISO50, focal length 80mm. The images were exported and saved as 16bit RGB tiff(AdobeRGB, sRGB, ProphotoRGB) images. To do the test, the RGB values of the RGB tiff images are processed through the ICC input profile to arrive at processed CIEL*a*b* values. A profiling tool such as ProfileMaker 5.0 and Monacoprofile 4.8 are used to do this. The processed CIEL*a*b* values are compared to the reference CIEL*a*b* values and these two values are used to calculate a ΔE.

Eco printing offers the perfect balance between getting all our printing jobs done without endangering the environment. It is important to realize that the printing industry is no exception to this rampant destruction of the planet's natural resources. In fact, surprisingly enough, its effect on the environment is an extremely harmful one. Like most other production operations, printing houses also produce harmful waste products that pollute the air we breathe in. They also put a great drain on precious natural resources. Printing houses emit what are known as volatile organic compounds (VOCs), caused by the use of petroleum-based inks, laminates, varnishes and adhesives. Studies show that these compounds, when inhaled, greatly increase the risk of asthma attacks. Eco printing, however, has a larger scope than is apparent. Eco printing has a dual essence. In order to understand what it is really all about, the issue of conservation is no less important than the need to stop polluting the environment.