Loose emulsion

A petroleum industry term for a practically stable emulsion, in contrast to a less stable, or loose , emulsion. 

Loose Emulsion A petroleum industry term for a relatively unstable, easy-to-break emulsion, as opposed to a more stable, difficult-to-treat emulsion. See also Tight Emulsion. 

Loose Emulsion. A relatively unstable, easy-to-break emulsion. See also Tight Emulsion. 

Tight Emulsion. A practically stable emulsion, as opposed to a loose emulsion. 

Emulsions are dispersions of small droplets of one liquid in another liquid, neither liquid being soluble in the other. They are electrically stabilised by some type of surface active substances know as emulsifiers. When the amount of the emulsifier is small, the emulsion is relatively unstable ( loose emulsion) and the dispersed droplets coalesce fairly easily to give large drops ( cracking of emulsion). When the concentration of the emulsifier is large, the dispersed droplets are finer and the emulsion is hard to break ( tight or stable emulsion). 

As binders for fiherfill and nonwovens, the emulsions are applied to a loose web or mat, then heated to form a film that sticks the loose fibers together. Polyester (188—191), glass (192), and rayon (193) mats are bonded in this manner for a variety of end uses including quilting, clothing, disposable diapers and towels, filters, and roofing (see Nonwoven fabrics). 

In the foregoing we loosely talked about the intensity of a sensory attribute for a given sample, as if the assessors perceive a single (scalar) response. In reality, perception is a dynamic process, and a very complex one. For example, when a food product is taken in the mouth, the product disintegrates, emulsions are broken, flavours are released and transported from the mouth to the olfactory (smell) receptors in the nose. The measurement of these processes, analyzing and interpreting the results and, eventually, their control is of importance to the food... 

Although they are a relatively small volume product—approximately 75,000 tons produced in 1949 (126)—interest in asphalt emulsion has continued at a high level. Abraham (6) has reviewed the patent literature relative to the types of emulsifying agents used, while commercial practice has been discussed by Day (16). The most common emulsifiers are sodium or potassium soaps of tall oil, abietic acid, or Vinsol resin, or colloidal clays such as bentonite for adhesive base emulsions. Lyttleton and Traxler (53) studied the flow properties of asphalt emulsions, and Traxler (122) has investigated the effect of size distribution of the dispersed particles on emulsion viscosity. A decrease in particle size uniformity was found to be accompanied by a decrease in consistency because particles of various size assume a more loosely packed condition than do those of the same size. 

As an emulsion passes through an electrical field, the small water droplets are polarized and then stretched due o ihe polar attractions. This polarization greatly increases the speed and forte of impact of the parlt-< les upon one another as they speed toward the attracting electrode Because of the weakened him due to surface stretching and because of the greater collision force due to increased peed th< droplets unite more readily Ihe elec ire. fu-ld works better on a loose-red emulsion. irnl -. irrot tolerate... 

Even if a chemical desensitizer has been used, the safelight should not be turned on until at least halfway through the estimated development time. This is because film looses its sensitivity as development proceeds. If a desensitizer has been used, the safelight can be left on when the estimated halfway point has been reached (see Desensitizers, below). Without the use of a desensitizer, the safelight should only be turned on for brief intervals, 15 to 20 seconds at a time, after the estimated halfway point. Pyro developers aid in desensitizing the film by hardening the surface of the emulsion as development proceeds (see Pyro and Development by Inspection, below). 

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