Primer technology

The usable primer systems consist of a polymer binding agent matrix, a mixture of functional fillers, an organometallic palladium compound as catalyst for subsequent copper plating, diverse fillers for rheological adaptation to the application technique used, and a suitable solvent mixture [48]. 

Primer technology offers a raft of options for structuring three-dimensional interconnect devices. One possibility is to shape silk-screen printed films and then stabilize them by film insert molding (Section 3.1.3.1). Another option is to use tampon printing to transfer a circuit layout directly to a three-dimensional plastic body. 

FIGURE 3.24 Adhesion mechanisms, plastic - primer - copper [48] 

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PPG industries introduced a cathodic electrodeposition (ELPO) primer process, which led to every location on the primed part covered with paint. Other advances in primer technology are using thicker high-build primers for increased corrosion protection and flaw-hiding capabilities. 

The labeling procedure, based on established random primer technology (3) can be used with DNA of various types and purity see Chapter 15). The resulting fluorescein-labeled probes can be stored for several months, thus avoiding frequent labeling reactions. Valuable probe is not lost since a further purification step before hybridization is not required. 

At the time of the release of the component from the mould, adhesion is at its weakest level. Therefore, in the case of self-adhesive or primer technology, it is essential to demould cautiously as, once silicone and substrate are separated, no adhesion will form again. In the case of self-adhesive LR, upon cooling and after sufficient storage and/or further heat treatment, adhesion will develop to its utmost extent. This will be explained further in Section 11.11.1. It is essential that the plastic material used for the moulding of the hard substrate solidifies quickly at a high mould temperature. 

Printing technologies Plasma structuring Hot embossing Primer technology... 

Epoxy stmctural adhesives are used in an extraordinarily wide range of appHcations. They are available in essentially all of the forms discussed above, except for primer—Hquid combinations or as room temperature curing Hquids. The highest technology appHcation for epoxies is in aerospace stmctural... 

Acryhc stmctural adhesives have been modified by elastomers in order to obtain a phase-separated, toughened system. A significant contribution in this technology has been made in which acryhc adhesives were modified by the addition of chlorosulfonated polyethylene to obtain a phase-separated stmctural adhesive (11). Such adhesives also contain methyl methacrylate, glacial methacrylic acid, and cross-linkers such as ethylene glycol dimethacrylate [97-90-5]. The polymerization initiation system, which includes cumene hydroperoxide, N,1S7-dimethyl- -toluidine, and saccharin, can be apphed to the adherend surface as a primer, or it can be formulated as the second part of a two-part adhesive. Modification of cyanoacrylates using elastomers has also been attempted copolymers of acrylonitrile, butadiene, and styrene ethylene copolymers with methylacrylate or copolymers of methacrylates with butadiene and styrene have been used. However, because of the extreme reactivity of the monomer, modification of cyanoacrylate adhesives is very difficult and material purity is essential in order to be able to modify the cyanoacrylate without causing premature reaction. 

Significant advances in waterborne coatings have been made by PPG Industries utilizing epoxies as co-resins. These coatings are used in cathodic electrodeposited systems, widely accepted for automobile primers. Many patents have been issued for this important technology (50,51). 

Corrosion-inhibiting primers based on this technology have been in continuous service since they were first utilized with nitrile epoxies in the late 1960s. These inhibitors function by passivating the aluminum. In this process, water permeating the adhesive bondline carries a certain amount of inhibitor to the oxide surface. 

The need to identify replacements for chromate-based technologies has also resulted in the development of alternatives to resin-based corrosion-inhibiting primers. These are primarily inorganic barrier coating techniques, such as sol-gel processes, which may or may not include corrosion inhibitors. These are discussed in a later section. 

With the exception of coupling agent technology, primers for structural adhesive bonding have received little theoretical treatment in the literature beyond a discussion of mechanisms of corrosion inhibition by primer additives and limited discussion about statistical techniques for primer formulation. Perhaps because of the much more widespread use and greater economic importance of corrosion-protective coatings, the design and function of primers for these systems have... 

The ratio PVC/CPVC (or reduced CPVC) is a simple but profound index of primer film structure that is perhaps the most important parameter in all of paint technology [70]. The relationship of the reduced CPVC to film structure can be appreciated by reference to Fig. 8. This figure shows a representation of a dry primer film with a range of pigment volume fraction that increases from left to right. 

D. Heiger, High Performance Capillary Electrophoresis, Agilent Technologies Primer, Publ. no. 5968-9963E, Wilmington, DE (2000). 

R. Schuster and H. Schulenberg-Schell, A New Approach to Lower Limits of Detection and Easy Spectral Analysis, Agilent Technologies Application Primer No. 

U.S. EPA, Brownfields Technology Primer Selecting and Using Phytoremediation for Site Cleanup, EPA 542-R-01-006, Office of Solid Waste and Emergency Response, Technology Innovation Office, Washington, 2001. 

Gasification Technologies A Primer for Engineers and Scientists, edited by John Rezaiyan and Nicholas R Cheremisinoff... 

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