Paper absorbency

Paper absorbency is important for proper ink drying. A paper s surface should allow the ink vehicle to penetrate at the proper rate to achieve proper setting of the ink. If the surface is too absorbent, it causes low ink holdout and loss of gloss. If it is not absorbent enough, it causes ink to transfer to other sheets in a stack, or sheets to stick together. 

This salt is much more difficult to obtain in dry, pure form than is the corresponding sulfate. It is very soluble in water, but from concentrated solution it is deposited in crystals which in color are almost identical with those of the sulfate. Upon exposure to air, even during filtration with the pump, the crystals turn yellow through oxidation. Probably this is not due to greater ease of oxidation on the part of the solid salt but to the physical conditions that prevail. The saturated, cold solution is very viscous and sticky, and absorbent paper absorbs this liquid very slowly. Owing to the great solubility of the salt, the solution has a low vapor pressure and does not tend to evaporate in the air. Consequently, the crystals remain coated with a film of concentrated mother liquor which oxidizes very fast in the air. 

Argento-iodized paper will retain its good qualities for some weeks. Some persons even affirm that it may he kept for an indefinite period in a dry place. It is said, on good authority, to be much improved by exposing it for an hour or two to strong sunshine. When this is done, It should not bo excited imme. diatoiy after insulation, bnt kept for some days previously in the dark, since it has been found that paper absorbs light in sufficient quantity to react on a sensitive surface placed in contact with it la the dork. 

Table 4 and 5 show the color and optical density of photodecomposed 2-monosubstitutedamino-5-azidoben-zoic acid. The colors in table 4 were produced by UV irradiation to a filter paper absorbed with 30% methanol solution of azide compounds. The colors in table 5 were produced by UV irradiation to a grained aluminum plate or polyester film coated with 10% solution of mixture of novolak and azide compounds (10 3 ) solved in methylethylketone. 

The impregnated paper absorbs the relevant component of the solution and the component is partitioned between the impregnated paper and the solvent that... 

SPILL CLEAN-UP stop leak if possible absorb small quantities on paper evaporate on a glass or an iron dish in a fume hood, then bum paper absorb liquid spills with noncombustible materials (e.g, dry earth, sand, vermiculite), and transfer to chemical waste containers all equipment used when handling the product must be grounded remove all sources of ignition. 

Fig. 8.10 Effect of PVAM wet strength resins on paper absorbency...

Acid extracts were combusted for 2 min in a Packard, Tricarb Model 306 sample oxidizer. Three 0.5-ml aliquots of each of the cooled sulfuric acid extracts were transferred into combustion cones containing a paper absorbent. About 0.1 g of Combust Aid was added immediately prior to placement in the combustion basket of the oxidizer. Labeled C02 was trapped in Carbo-Sorb (approx. 7 ml) and scintillation cocktail containing Permafluor V (about 13 ml). Radioactivity was measured by liquid scintillation analysis in a Beckman LS 6800 counter and corrected for efficiency and recovery. Data collected as dpm s were converted to mg based on the amount of paraquat ion in the original spray solution. 

C.K.S. Pillai, C.P. Sharma, Review paper absorbable polymeric surgical sutures chemistry, production, properties, biodegradability, and performance. J. Biomater. Appl. 25 (2010) 291-366, doi 10.1177/0885328210384890. 

Further, aramid paper is less hygroscopic than cellulose paper [40]. However, a poly(ether imide) paper absorbs less water than a conventional aramid paper [41]. Therefore, especially under humid conditions, a poly(ether imide) paper is superior to an aramid paper. 

The formation of metal complexes is often accompanied by very striking changes in color. One example is the use of aqueous solutions of C0CI2 as invisible ink. This ink is essentially colorless however, when the paper on which it was used is heated, the ink becomes a legible blue color. This color gradually fades as the paper absorbs atmospheric moisture. The phenomenon responsible for the appearance of color is shown by equilibrium (3). 

The next stage is to separate the plastic from the paper. This was initially a problem as both are similar in density. The solution is to wet the mixture. The paper absorbs water and as a result becomes denser than the plastic. 

When volumes less than about 5 mL must be filtered, there is a danger of losing material on the filter paper, because the paper absorbs a significant volume of liquid. A Pasteur filtering pipet (Sec. 2.5) should be used in such cases. The liquid mixture to be filtered is transferred by pipet into the filtering pipet as shown in Figure 2.51. The plug should be rinsed with about 0.5 mL of solvent to maximize the recovery of the solute. 

The amount of PAE resin required in hygienic paper production is between 0.1% and 4% calculated on dry fibers. Depending on the addition level, the relative wet-strength can be increased to over 35% without significantly drop in paper absorbency. 

PEI was the first effective wet-strength resin used during paper manufacturing in neutral/alkaline conditions without negative effect on paper absorbency. The mechanism of PEI differs from that... 

This weight distribution shows the effects of moisture transfer between the categories in the refuse during storage and handling. For example, the food waste tends to lose moisture and the paper absorbs moisture. 

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