Printability tests

The level of discharge treatment used in this study is quite high, but not by any standards excessive. (Experimental details can be found in Ref. 7.) It corresponds to the level of maximum autohesion under the heatsealing conditions employed in this study (Fig. 3). It also corresponds to a level at which the film used would pass a searching printability test. The surface energy measured... 

It is recommended to carry out miscibility tests to check that no separation (flotation, sedimentation, coagulation) will occur due to the preservation treatment. This is very important for coating slurries preservation where any rheological change in these complex formulations can destabilise the coating. These tests can include enduction ( draw down test ), brightness test, printability tests. 

A. Mackay and A. Wright, Correlation between laboratory printability testing and commercial printing, 50 Appita Annual General Conference, APPITA, Rotura, 1996, p. 405. 

The main purpose of this chapter is to describe methods of modifying polyolefin surfaces in such a way as to render them printable, and also to describe the tests that are available for determining the effects of treatment and... 

An overview of the lithographic process is presented with particular emphasis on the role that surface and colloid chemistry plays. Recent research has shown the importance of these chemistries in fountain solution, ink and plate interactions and the effect of these interactions on the dynamic behavior of the lithographic ink on press. Data on the rheological behavior of preformed fountain solution/ink emulsions is presented along with an evaluation of prints made with the inks on an actual press run. The importance of pre-testing the emulsification behavior of printing inks in predicting their printability is demonstrated. 

To overcome these difficulties, printable compositions were formulated. The printable sensor inks contained three major components the metal oxide, glass frit for adhesion, and organic vehicles that burn off during firing. A catalyst, in the form of a precious metal chloride, was applied and fired on the sintered metal oxide layer alternatively, precious metal resinate solutions were incorporated directly into the ink. Initial tests of these printable layers demonstrated sensor resistivities that changed rapidly and reversibly by as much as a factor of 14. The response time was a few seconds while recovery took about 1 min, although complete recovery was often longer than 16 h. 

Whereas actual measurements of contact angles are usually made in science laboratories, the principles are exploited in the water-break test and in the use of liquids of different surface tensions to assess the printability of polyolefins. 

However, there still remain many important paper properties which are not yet measurable on-line, and where on-Kne measurements will probably not be available in the near future. Most important to note in this category is printabihty. A printability sensor, e. g., would be able to predict missing dots in a real printing test. 

Fig. 6 Influence of contaminants released from silicone gasket materials on the corrosion behavior of 316L. Ex situ immersion test H SO, pH 2, 500h, 100°C. LfMliquid injection moldable, SP screen printable...

The lead-free transition will have some impact on the stencil printing process. Printability of solder paste depends on flux formulation, but not for all alloy types. Experience has proven that there are no differences when printing lead-free solder pastes than when printing tin/lead solder pastes. Formal testing has verified that the printed volume of several lead-free solder pastes and tin/lead solder pastes were the same statistically when using the same stendl, printing equipment and boards (Figure 2). 

In this section, the most important methods of testing coated papers will be described. The printability and the final print quality can often be successfully predicted on the basis of these relatively simple tests. 

Using a test vehicle which included QFPs with pitches ranging from 0.3 to 0.5 mm, and CSPs with pitches ranging from 0.4 to 0.6 mm, a study was conducted to understand the manufacturing impact of three no-clean, lead-free solders from the Sn-Ag-Cu family compared to a standard no-clean eutectic Sn-Pb solder paste. The evaluation focused on printability, solder paste pot-life, wettability, reflow process window, and inspection [33]. 

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