Ejection stability

When metal particles or metal powder are used instead of a pigment or a dye in an UV curable ink composition, there is a problem in that it is difficult to sufficiently exhibit properties such as gloss provided inherently by the metal. In addition, the storage stability of the composition is lowered. This causes a problem in that the composition is turned into a gel, and thus ejection stability of the composition is lowered due to the increase of the viscosity (10). The negative influence of the metal powder can be eliminated by a surface treatment with a fluorine type silane compoimd or a fluorine type phosphoric add ester. 

When the first solvent (1,2-hexanediol) content is less than 3%, bleeding in the resulting images occurs. In contrast, when the content is more than 6%, the viscosity increases and inferior storage stability is observed. Further, the ejection stability test shows a lot of dots missing and deviation (15). 

An inkjet recording ink composition, which is particularly suitable in textile use, has been described. The composition exhibits a high rub fastness and a dry cleaning resistance, as well as a high ejection stability. This can be achieved by adding a poly(urethane) resin to the ink composition. A key factor is that the poly(urethane) resin should contain 50% or more of a tetrahydrofuran-insoluble portion. Then, the resulting inkjet composition could be superior in rub fastness, dry cleaning resistance and ejection stability. 

A radiation curable inkjet ink composition has been described that contains vinyl monomers, a photopolymerization initiator such as described in Ref. (8) and poly(siloxane) that allows marking, can be performed on a package substrate or a semiconductor substrate. The ink composition has the excellent visibility of a recorded image, ejection stability of the ink, and scratch resistance. 

The poly(siloxane) is preferably a polyether or polyester-modified poly(dimethyl siloxane). The hydrophdic-lipophilic balance value of the poly (siloxane) should be in a range of 9 to 12. In this range, the visibility of a recorded image, the ejection stability, and the scratch resistance becomes excellent. 

The facility with which a-cleavage occurs in solution depends on the stability of ttae adical fragments that can be ejected. Dibenzyl ketone, for exan le, is readify cleav jjiboto-lytically. Similarly, r-butyl ketones undergo a-cleavage quite readify on p ioCo in solution. ... 

We can use Fig. 17.13 to predict the type of disintegration that a radioactive nuclide is likely to undergo. Nuclei that lie above the band of stability are neutron rich they have a high proportion of neutrons. These nuclei tend to decay in such a way that the final n/p ratio is closer to that found in the band of stability. For example, a l4C nucleus can reach a more stable state by ejecting a (3 particle, which reduces the n/p ratio as a result of the conversion of a neutron into a proton (Fig. 17.15) ... 

A carbanion can be a good leaving group in SNl-type solvolyses when the anion is highly stabilized by strong electron-withdrawing substituents. Mitsuhashi reported some examples of such reactions for substrates which eject an anion stabilized by cyano (and nitro) groups [81] (Mitsuhashi, 1986), [82] (Mitsuhashi and Hirota, 1990) and [83] (Hirota and Mitsuhashi,... 

REP, a rod of metal or alloy, referred to as a consumable electrode, is rotated at high speed about its longitudinal axis. Simultaneously, it is melted gradually at one of its ends by a heat source, such as an arc, a plasma, or an electron beam, etc. A thin film of the molten metal is detached from the rod end and ejected from the periphery of the rod by centrifugal force, forming spherical droplets. The atomization is conducted in an inert atmosphere, usually argon. Helium may be used to increase arc stability and convective cooling efficiency of droplets. 

A number of thermal stability tests arc available, some of which have developed into national (DIN) or international industrial standards (ISO). Pigments in thermoplastic systems, for instance, are studied under heat extrusion conditions [110]. The colorant to be tested, possibly together with titanium dioxide, is dispersed in the thermoplastic, using a mixer and a granulating extruder (Sec. 1.8.3). The pigmented test pellets are then fed into a screw extruder which ejects a standardized test specimen with defined dimensions [111]. Starting at the lowest possible temperature level, the extrusion temperature is increased by intervals of 10 or 20°C between samples. 

At the stability boundary, ion motion is in resonance with this modulation voltage, and thus ion ejection is facilitated. Axial modulation basically improves the mass-selective instability mode of operation. 

Easily ionizable anthracene forms the cation-radical as a result of sorption within Li-ZSM-5. In case of other alkali cations, anthracene was sorbed within M-ZSM-5 as an intact molecule without ionization (Marquis et al. 2005). Among the counterbalancing alkali cations, only Li+ can induce sufficient polarization energy to initiate spontaneous ionization during the anthracene sorption. The lithium cation has the smallest ion radius and its distance to the oxygen net is the shortest. The ejected electron appears to be delocalized in a restricted space around Li+ ion and Al and Si atoms in the zeolite framework. The anthracene cation-radical appears to be in proximity to the space where the electron is delocalized. This opens a possibility for the anthracene cation-radical to be stabilized by the electron s negative field. In other words, a special driving force for one-electron transfer is formed, in case of Li-ZSM-5. 

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