No abstract

In Electrophotography printing technique with liquid toners, large quantities of ink are deposited on photoreceptor. Voltage variations during the development phase (ΔV=200V) will directly influence the thickness of ink layer on photoreceptor. Optimal reproduction is achieved when smallest image elements (screen dots) have smallest possible diameter, and respectively higher optical density. Suitable method for reproduction analysis is based on spectrophotometric measurement of halftones and on optical densitometry. By adjusting the voltage during development (II. phase) will allow largest manipulation of color (ΔE RR = 10.01). Optimal results are achieved with voltage of -125 V. Under this conditions, average printed screen element had average diameter of 56.9 μm and a maximum reflectance of R=33.50%. Variation of voltage on other two developing devices affect only slightly the color reproduction (ΔE DEV =1.26; ΔE SQU =0.94.) and have lower impact on the size of screen elements (Δd DEV =8.1 μm; Δd SQU =4.1 μm).

Packaging can be briefly defined as a science, method and technology for product preservation. The function of packaging is to protect the product that is packed in it and to protect the environment from the content inside the packaging. As a result, the products can be gaseous, liquid or solid.[1-3] The packaging must be suitable for use, i.e. handling, transport and distribution. It should inform the potential and the actual buyer and it should "sell the product". [4,5] An important part of the packaging design is the material from which it will be made. The basic conditions that packaging must meet are the following: strength on material pressure, elasticity, plasticity, stiffness and resistance to strain, toughness, mechanical endurance and printing.[4] Packaging must protect the content and be protected itself from oxidation, moisture, odor, chemical agents and microbes. To meet these requirements, polymer materials and nanotechnology are now being used.[5,6] Packaging can also be made according to the materials, purpose in traffic, durability and function.

The machine printing and rapid cultural development in Europe begins with the discovery of metal lettering at the end of the 15th century. This printing technique has been named the letterpress printing and is one of the greatest inventions of mankind. The development of printing was one of the main indicators of the development of individual countries. We believe that today in the world and in Europe the Croatian development of that age is significantly neglected. This paper presents European development and development in Croatia. This paper will contribute to a more accurate evaluation of Croatian printing and cultural level of that time by displaying Croatian achievements of that era, the printing staff, printed works and printing houses, throughout European and Croatian development of printing.

The basic directions of the ecological sustainability of the sheet fed offset printing are in the area of the application of the renewable and recycled raw materials for the production of the printing materials, in the decrease of the energy consumption, the usage of the energy from the renewable sources and in the production without waste; or if the waste was formed that it could be used in the same production or in another one. The analysis of the life cycle assessment offset printed matter has shown all the importance of the recycled paper usage in relation to the usage of the paper made from the virgin fibres and with it the possible influence on the quality of the environment. The main object of these investigations is the contribution to the explanation of the mechanism of the deinking flotation of prints made with the ink based on mineral oils and prints with greater share of the renewable raw material. Some prints were exposed to moist heat ageing before recycling. The brightness of handsheet, number and area of specks and chromatic coefficient in relation to the ink formulation and the conditions of the moist heat ageing of prints are discussed.