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Electrical grade

In the manufacture of a laminate for electrical insulation, paper, which is the best dielectric, is normally selected as the base reinforcement. An electrical grade of paper is in fact a better dielectric than the resin and thus in eonditions... [Pg.657]

Resins for this purpose generally use melamine-formaldehyde ratios of 1 2.2 to 1 3. Where electrical grade laminates are required the condensing catalyst employed is triethanolamine instead of sodium carbonate. [Pg.688]

Electrical grades Modified Glass modified Modified 30% GF ... [Pg.546]

This paper reports the results of a molecular-level investigation of the effects of flame retardant additives on the thermal dedompositlon of thermoset molding compounds used for encapsulation of IC devices, and their implications to the reliability of devices in molded plastic packages. In particular, semiconductor grade novolac epoxy and silicone-epoxy based resins and an electrical grade novolac epoxy formulation are compared. This work is an extension of a previous study of an epoxy encapsulant to flame retarded and non-flame retarded sample pairs of novolac epoxy and silicone-epoxy compounds. The results of this work are correlated with separate studies on device aglng2>3, where appropriate. [Pg.213]

EGA. The overall ion profiles for the semiconductor grade epoxy compounds are presented in Figures 9 and 10 for samples F(FR) and G(no-FR), respectively. Very little outgasslng is observed from these samples below 200 C, in marked contrast to the results obtained for the electrical grade epoxy samples. These data clearly reflect the effects of the more stringent processing controls employed in the production of the semiconductor grade materials. Also, because of the lower out-... [Pg.224]

Elemental Analyses. The X-ray fluorescence measurements of Table 11 indicate a somewhat higher total Br content for the semiconductor grade novolac (sample F) than for the electrical grade (sample A). However, the data of Table 111 indicate halide concentrations in the extract that are an order of magnitude lower for the semiconductor grade novolac (sample G) is a factor of three material (sample F). [Pg.229]

Since no difference was found between FR and non-FR formulations in device aging studies, some other cause must account for the relatively early failures observed for devices molded in the electrical grade epoxy material and aged under bias at 200°C. These failures are attributed to chloride contamination present in the non-semiconductor grade epoxy resin. The extractable Cl concentration is a factor of four higher than Br, and this is correlated with a much higher concentration of CHoCl than CH Br in the EGA data below 200°C. The high Br concentration is also attributed to the... [Pg.229]

Epoxy resin can have varying amounts of inorganic material remaining in the product after its synthesis. One of these is sodium chloride, which is formed by the reaction of sodium hydroxide with epichlorohydrin molecules, as described in Chap. 2. This is important in electrical applications because the sodium salt can be hydrolyzed and can degrade electrical properties. Some epoxy resin manufacturers will offer special ultrapure electrical grades or low-chlorine grades of epoxy resins for application where this is an important factor. [Pg.13]

Nonconductive fillers are employed with electrical-grade epoxy adhesive formulations to provide assembled components with specific electrical properties. Metallic fillers generally degrade electrical resistance values, although they could be used to provide a degree of conductivity as discussed above. [Pg.174]

The effect of electrical-grade fillers (e.g., silica) on the electrical properties of the adhesive is usually marginal. Generally fillers are not used to improve electrical resistance characteristics such as dielectric strength. The unfilled epoxy is usually optimal as an insulator. Also under conditions of high humidity, fillers may tend to wick moisture and considerably degrade the electrical resistance properties of the adhesive. [Pg.174]

The one exception where certain fillers can provide electrical property improvement is in arc resistance. Here hydrated aluminum oxide and hydrated calcium sulfates will improve arc resistance if cure is sufficiently low to prevent dehydration of the filler particles. Electrical-grade fillers generally improve the arc resistance of cured epoxy systems, as indicated in Table 9.10. [Pg.174]

Electrical grade High dielectric strength Circuit breakers... [Pg.440]

Polyamide (nylon) reinforcements can be in fabric form to provide excellent electrical grade laminates for conventional industrial use. Type... [Pg.462]

See other pages where Electrical grade is mentioned: [Pg.304]    [Pg.316]    [Pg.296]    [Pg.553]    [Pg.124]    [Pg.921]    [Pg.231]    [Pg.498]    [Pg.648]    [Pg.654]    [Pg.688]    [Pg.760]    [Pg.215]    [Pg.217]    [Pg.217]    [Pg.224]    [Pg.224]    [Pg.229]    [Pg.231]    [Pg.592]    [Pg.740]    [Pg.296]    [Pg.553]    [Pg.148]    [Pg.316]    [Pg.618]    [Pg.124]    [Pg.789]    [Pg.238]    [Pg.449]    [Pg.102]    [Pg.2872]    [Pg.231]    [Pg.498]    [Pg.648]    [Pg.654]   
See also in sourсe #XX -- [ Pg.330 , Pg.452 ]



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