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Applied films

Bubbling a film defect, temporary or permanent, in which bubbles of air or solvent vapour, or both, are present in the applied film. [Pg.682]

A number of attributes of topical drug systems that may be classified as cosmetic can make patients more or less willing to use their medications (compliant). These include ease of application, the feel of the preparation once it is on the skin, and the appearance of the applied film. Ideally, the application should be undetectable to the eye and neither tacky nor greasy. Certain items,... [Pg.238]

This expression is independent of the film thickness. Thus, when one considers reflective monitoring of metal film etching, only at the interface between film and substrate will a change in reflectivity be observed due to the change in refractive index. Although this is extremely useful for end point detection one still must apply films of known thickness for cases in which etch rate information is desired. [Pg.258]

Wedge test results suggest that the curing process (e.g., percent crosslinking) of the epoxy-polyamide primer system is not affected by the addition of organosilanes, but may be affected by NTMP. The results of substrate surface characterization, adsorption behavior of applied films, and evaluation of candidate inhibitors by chemical, mechanical, and electrochemical test methods are presented. Mechanisms to explain the observed behavior of the various phosphonate and silane polymer systems are discussed. [Pg.234]

A simplified model using a stagnant boundary layer assumption and the one-dimension diffusion—convection equation has been used to calculate wall concentration in an RO module. The integrated form of this equation, the widely applied film theory (41), is given in equation 8. [Pg.148]

Deposition has been carried out from a standard bath with a magnetic field applied, both parallel and perpendicular to the substrate [29]. Differences were found in the film properties only for a field perpendicular to the substrate. The transmission of the films in the nonabsorbing region was ca. 10% higher (see Sec. 4.1.3.1). The films deposited with the field were up to three times thicker than those deposited using the same conditions but in the absence of a field. The dark resistivity of the field-applied films was much less than that of the field-free ones (see Sec. 4.1.4.1). The cause of these effects is not clear. [Pg.168]

The definition of hiding power is based on a black and white contrasting support upon which the film of coating is applied. The thickness h of the applied film is determined at the point at which the contrasting surface just disappears, as judged... [Pg.30]

When a ferrous alloy is immersed in phosphoric acid, il initially forms a soluble phosphate. As the pH rises at the mclal/solutiun interface, the phosphate becomes insoluble and crystallizes epitaxially on Ihe substrate metal. The phosphate coating thus produced consists of a nonconduciivc layer nf crysinlx that insulates the metal from any subsequently applied film and provides a topography with enhanced tooth" for increased adhesion. The cry stals insulate microanode and microcathode centers caused by stress or imperfections in the metal surface. This greatly reduces Ihe severity of electrochemical corrosion. [Pg.435]

Pretreatment primers. In this method of use the silane may be applied from a solvent solution, by vapour phase deposition or by plasma deposition although solvent application is the more usual. The solution usually contains water and silane at a concentration of 1-2 wt%. The applied film may be water washed before subsequent coating/bonding and/or heat cured. The solvent(s) used may be important in both the stability of the solution and the performance, particularly in the wet adhesion. It has been shown that the presence of water either in the solution or as a final rinse is important, particularly in the case of AAMS and presumably other silanes [1]. Other factors which are important include the concentration of silane the pH of the solution the thickness of the silane film deposited. [Pg.24]

The trialkoxysilane compounds thus satisfy two requirements indicated by Zisman (21) for useful finishing agents. They are able to displace water from the substrate surface and to prevent its readsorption. However, it was pointed out (21) that the applied film of finishing agent must be resin-wettable—i.e., yc > 40 dynes/cm., to allow good contact between adhesive and adherend. The results with the p-chlorophenyl-... [Pg.69]

Mildewcides protect the applied film from fungus growth. [Pg.3289]

The rotor is very flexible regarding batch size. Minimum batch size may be as low as 1/8 of working capacity. However, when applying films, the batch size should be selected such that the nozzle is immersed below the surface of the bed. This minimizes the potential that the high velocity atomization air will not blow some coating droplets through the bed where they may be spray dried and collected in the filter. [Pg.370]

A discussion on spraying is incomplete without a discourse on nozzle maintenance and testing. In any coating application, the spray nozzle is the single most critical component. Its performance dictates droplet size control, the quality of the applied film and the reproducibility of the resultant product properties. These include appearance, potency, film coating efficiency, and release characteristics. In retrospective process troubleshooting, spray nozzle performance is often the leading cause of product deviations. [Pg.377]

Note-. This is a typical cold cream formulation. The cooling effect comes from the slow evaporation of water from the applied films. The aromatic is added at as low a temperature as possible to prevent its loss by volatilization during manufacture. [Pg.77]

Here, we investigated the properties of the applied films of DCNDBQT by different east methods - spin-eoating and vacuum sublimation. [Pg.695]

Fig. 27 Plots of the normalized change of the absorbance (AA/F) vs the used film thickness. At 308-nm irradiation (o) a maximum value is reached. In the case of 248-nm irradiation ( ) a maximum value is reached within the applied film thickness. REPRINTED WITH PERMISSION OF [Ref. 60], COPYRIGHT (1996) Springer Verlag... Fig. 27 Plots of the normalized change of the absorbance (AA/F) vs the used film thickness. At 308-nm irradiation (o) a maximum value is reached. In the case of 248-nm irradiation ( ) a maximum value is reached within the applied film thickness. REPRINTED WITH PERMISSION OF [Ref. 60], COPYRIGHT (1996) Springer Verlag...
Most conventional lacquers are completely thermoplastic in nature, although some of the new lacquer types do cure chemically. Others impart markedly different protective or decorative properties to the applied film. A list of the key innovations that have occurred in the lacquer industry over the past 40 years is shown in Table VII. [Pg.1077]

The two associative thickeners examined in the remainder of this text whose synthesis has not been discussed are hydrophobe-modified alkali-swellable emulsions (HASE) discussed in Chapters 25, 27, and 28, and hydrophobe-modified (hydroxyethyl)cellulose (HMHEC, discussed in Chapters 17, 18, and 27). HASE thickeners, by far the lowest cost hydrophobe-modified thickeners produced, should have achieved the largest market share on the basis of cost of production, but this situation does not appear to be the case (discussed in Chapter 28) in large part because of the poor properties observed with the lowest cost latex, vinyl acetate, used to form the continuous film. The applied-film properties 46) of vinyl acetate can be substantially improved through the use of HEUR polymers. HMHEC, synthesized by a matured (30-year-old) commercial slurry process (47) has achieved commercial acceptance, in large part because of linear high shear rate viscosities achieved in blends with HEUR thickeners (Chapter 27). [Pg.162]

The nature of the shear viscosifying component and possibly the magnitude of the shear viscosity can contribute to the magnitude of the DUEVs (42). This information will relate to many applications in which extrusion rates are not totally extensional in nature (e.g., automotive sealants and mobility control studies (23, 26) in which the permeability of the formation is a critical factor). For roll-applied films, the magnitude of these different deformation rates (16) are significantly different (Figures 8 and 9) and their relative contribution to a formulation s performance may be complex. [Pg.257]

Hydrophobically modified, ethoxylated urethanes (HEURs) are the thickeners of choice in exterior coatings and in corrosion-resistant, high-gloss industrial latex finishes. This chapter presents an overview of our research efforts and discusses approaches to the synthesis of HEUR polymers with different molecular architectures, geometrical influences on solution properties, and viable mechanisms by which this class of associative thickener effects desirable coatings rheology and applied film properties. [Pg.496]


See other pages where Applied films is mentioned: [Pg.295]    [Pg.224]    [Pg.431]    [Pg.99]    [Pg.186]    [Pg.275]    [Pg.159]    [Pg.170]    [Pg.4]    [Pg.1305]    [Pg.321]    [Pg.185]    [Pg.189]    [Pg.189]    [Pg.354]    [Pg.36]    [Pg.1735]    [Pg.364]    [Pg.376]    [Pg.275]    [Pg.197]    [Pg.761]    [Pg.592]    [Pg.593]    [Pg.380]    [Pg.274]    [Pg.320]    [Pg.459]    [Pg.485]    [Pg.495]   
See also in sourсe #XX -- [ Pg.279 , Pg.285 , Pg.288 , Pg.294 ]




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