Types of polishers

A wide variety of polishing bed designs are employed. These may be either externally or internally regenerated and supplied with various grades of tough gel or macroporous resins. The selection of a deep-bed (i.e., 36-48 inches, 900-1,200 mm deep) polisher depends on the specific operating circumstances. Types of polishers include ... 

Use of a shoe polish imparts high gloss, maintains the supple hand of the leather (qv), and increases the weather resistance of the leather (3,57—59). Three general types of polishes are produced solvent pastes, self-polishing liquids, and emulsion creams. Solvent pastes represent ca 60% of the market (58). 

Figure 3.7 shows a brief history of polishing practice. Although the rotary table type is one of the most popular polishers, many other types of polishers have been introduced by several manufactures over the years. Each type has its own characteristic features [22]. 

FIGURE 3.7 Schematic illustration of different types of polishers rotary with multitable and multihead (1), small head (2), small table (3), linear motion type (4), fixed abrasive type (5), and grinding t5 pe (6). 

There are four main types of polishing pads currently used for CMP process. They are differentiated by their microstructures and have different physical and mechanical properties. The four types are [1,2] as follows ... 

The key features, properties, and typical uses of these four types of polishing pads are listed in Table 5.1 [1,2]. 

TABLE 5.1 Key Features, Properties, and Applications of Different Types of Polishing Pads [1,2]. 

What are the differences in microstructures of the four main types of polishing pads Suggest an additional type. 

Petroleum jelly a translucent, yellowish to amber or white, hydrocarbon substance (m.p. 38-54°C) having almost no odor or taste derived from petroleum and used principally in medicine and pharmacy as a protective dressing and as a substitute for fats in ointments and cosmetics also used in many types of polishes and in lubricating greases, rust preventives, and modeling clay obtained by dewaxing heavy lubricating-oil stocks. 

Commercial polishes which claim to remove scratches from plastics are based either on abrasive particles suspended in a solvent or on a silicone polymer. The first physically smooths the edges of scratches in acrylic, polycarbonate and other rigid plastics when applied at right angles to the scratch. The second type of polish fills the scratch with a silicone polymer which wets the surfaces of flexible plastics, evens feults in surfaces and imparts high gloss. Because silicone polymers have very low surface tensions, it is very difficult to re-treat or remove polishes, so their use must be considered irreversible. Commercial polishes have not been evaluated for use on plastics in museum collections. 

Before CMP removal rate uniformity is discussed, the types of CMP, which are shown in Figure 16.1, are introduced. The carriCT type differs depending on the equipment. This means that the controllability and results of CMP removal rate uniformity also differ depending on the equipment. Several types of polisher are shown in Figure 16.1 [1]. The following is a brief explanation of the features of each polisher type, including... 

There are basically two types of polishing electrolytic (electrochemical) and mechanical. Each will be discussed separately. 

Depth filters are usually preferred for the most common type of microfiltration system, illustrated schematically in Figure 28. In this process design, called "dead-end" or "in-line" filtration, the entire fluid flow is forced through the membrane under pressure. As particulates accumulate on the membrane surface or in its interior, the pressure required to maintain the required flow increases until, at some point, the membrane must be replaced. The useful life of the membrane is proportional to the particulate loading of the feed solution. In-line microfiltration of solutions as a final polishing step prior to use is a typical apphcation (66,67). 

The different types of furniture pohshes include hquid or paste solvent waxes, clear oil pohshes, emulsion oil pohshes, emulsion wax pohshes, and aerosol or spray pohshes (3). Nonwoven wipes impregnated with pohsh ingredients have been targeted at consumers who do not wish to expend the time to dust before polishing (11). Compilations of representative formulas are given in References 3, 4, 12, and 13. Paste waxes contain ca 25 wt % wax, the remainder being solvent. Clear oil pohshes contain 10—15 wt % oil and a small amount of wax, the rest being solvent. Aerosol or spray products may contain 2—5 wt % of a sihcone polymer, 1—3 wt % wax, 0—30 wt % hydrocarbon solvent, and ca 1 wt % emulsifier. The remainder is water. 

Miscellaneous Clarifiers Various types of filters such as cartridge, magnetic, and bag filters are widely used in polishing operations, generally to remove trace amounts of suspended sohds... 

The effects of surface emissivity are exaggerated in high-temperature applications, and particular attention should be paid to the selection of the type of surface of the insulation system. Low-emissivity surfaces such as bright polished aluminum reduce heat loss by inhibiting the radiation of heat from the surface to the surrounding ambient... 

Glass-reinforced aluminum foil with either a bright polished or white lacquer surface is utilized with most types of insulant. Primarily it is used as a vapor control layer or as a means of upgrading the fire properties of plastic foams, but it does give a semi-decorative finish to the insulation. It is therefore often use where the insulation is open to view but located away from direct risk of mechanical damage. 

Preferential corrosion or attack at many other types of crystal defect may also be best illustrated during the etching of metallographically polished... 

Figure 1.53 shows diagrammatically various types of pits that can range from hemispherical with a polished surface, in which crystallographic etching has been completely suppressed, to crystallographic pits whose sides are composed of the crystal planes that corrode at the slowest rate. Pits formed on Ni during anodic polarisation in an acetic acid-acetate buffer of pH 4-6 are shown in Fig. 1.54. 

The characteristics of a polished surface are that it should be level on a macroscopic scale related, for example, to machine and grinding marks of 1-5 /im depth, and be smooth and bright on a microscopic scale typically 1-100 nm size for fine grained metal. To achieve dual levelling and smoothing a solution must satisfy three requirements by including three types of constituent ... 

The key properties here are hardness and wear resistance, ability to. stand minor knocks and dents without cracking and resistance to various domestic chemicals. These vary with type of appliance, e.g. detergent solutions are important for washing machines, while a fridge will be required to withstand fruit juices, ketchup and polishes. Good colour and appearance in white and mainly pastel shades will be expected. Corrosion resistance is required, especially for washing machines, and domestic appliances frequently have to withstand humid conditions in kitchens. 

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