Wetting action

Also known as surfactants and stool softeners, emollients (e.g., salts of docusate) act by increasing the surface wetting action on the stool leading to a softening effect. They reduce friction and make the stool easier to pass. These agents are not recommended for treating constipation of long duration. 

Fig. 20. Nucleation from pits on a solid surface. The foregoing bubble shapes exist if the liquid has good wetting action on the solid.

Abrasive cleaners arc used lo remove soils and stains from hard surfaces that are durable lo the scouring action. Such surfaces include stainless steel and porcelain plumbing fixtures, metal and ceramic cooking utensils, and various stone, metal, and ceramic building surfaces. Typically, these products consist of a very high level of abrasive (commonly silica flour) with moderate to low levels of a dry chlorine bleach (KDCC or chlorinaled trisodium phosphate) and low levels of surfactant (LAS) and builder (STP) for wetting action and improved stain removal... 

Table I shows the overall variation in the weights when the simulated-flood procedure was applied to similar pairs of identical books over an 8-mo period. The simulated flood was applied to these books as if they were loosely packed on the shelf—i.e., stored with minimum pressure applied to them. The relationship of each book s dry weight with the temperature and relative humidity of the room appears to have been comparable. The variability of the wetting action of both types of books is also similar however, the variances (the standard deviation squared) associated with the weights of the drained books are significantly different (statistical significance reported at the 95% confidence level unless otherwise noted) by use of an F-test (3). Since the handling of book pairs—i.e., one uncoated- and one coated-paper book—was the same in preparing samples for subsequent restoration studies, it might be concluded that drainage water from the books containing uncoated paper could be different from books with coated paper.

The excellent wetting action of LEONIL EB results in very good wetting out even in loom-state fabrics and rapid penetration of the size film. 

The Ink formulations usually contain an unsaturated monomer or prepolymer, a radical precursor and/ or an actinic sensitizer, a polymer vehicle base, and pigmentation. Recent formulations Include polyunsaturated polyenes, and polyacrylates with thiol or benzoin radical sources.. The acid or hydroxyl content of the resin base is usually varied to adjust the water or oleophillic wetting action of the composition. 

Another function of surface active polymers such as PVA is their wetting action. This can be seen from Table 6.5 where the advancing contact angle of small droplets of boehmite sol with non-ionic surfactant on a hydrophobised alumina substrate are given for increasing PVA concentration. Aging time of the droplets on the substrate was 4 min. 

Amphoteric surfactants offer an excellent degree of lubrication, corrosion inhibitor, and wetting action and provide a protective colloid for silk and wool processing. The major uses of amphoterics are in the scouring and dyeing of protein fibres to prevent chafing, crack marks and crow s feet. Amphoterics are comparatively expensive and some of them are not heat stable and hence cannot be used at elevated temperature. 

As already noted, however, in lithography we are not operating at equilibrium we are not waiting for spontaneous wetting action we are forcing the wetting action. The pressure and shearing forces at roller nips are purposely far in excess of the ink s viscous resistance to flow, to assure that the ink will move a small but finite distance at the ink-to-ink roller couples, within 10 2 to 10 second dwell times. 

Dishwasher Rinse Aids are formulated from the Hamposyl sarco-sinates and low-foam nonionics. The sarcosinate surfactant raises the cloud point and solubility of the nonionic and increases wetting action without contributing added foam. 

Mixtures show a less effective wetting action of the solution in comparison to single ionic species on the SH surface where the increased topography of the coating leads to a significant increase in the contact angle. The presence of non-ionic... 

Questions of plant-leaf wetting are examined in [8, p. 374]. Improvements in wetting of leaves can be achieved by the use of surfactants in the formulation, in combination with other reagents. Substances that improve the wetting action of various formulations are termed wetting agents. 

MACKADET RS is an optimum blend of sulfosuccinate and lauryl sulfate for use as an economical, in place, carpet and upholstery shampoo. The use of the sulfosuccinate reduces the wetting action upon the carpeting, thereby reducing the drying time. 

K. L. Yung, J. Kong, and Y. Xu, Studies on flow behaviors of polymer melts in nanochannels by wetting actions. Polymer, 48, 7645 (2007). 

---