Molding color

Colorability is another reason IDs select plastics for many products. Molding color into a product eliminates finishing and painting operations, thus reducing costs. Beyond cost, integral color also masks the nicks, chips and scratches that impair appearance during the life of the product. Color effects are almost limitless. Transparent, translucent, pearlescent, fluorescent, or marbleized colors are readily available for use in plastics. 

Balloons today are still made from the rubber latex from the rubber tree using molds. Color is added as desired. 

Specialized training is an absolute requirement for technical service personnel. A typical example is a person involved in supporting a polymer for which the use is the manufacture of rotationally molded consumer products. The technical service person is expected to be reasonably familiar with topics such as polymer rheology evaluations, gel-permeation chromatography, rotational molding, color science, regulatory requirements for use, mechanical and photochemical behavior of the pigmented polymer, optics, and so forth. Expertise of this variety cannot be expected to be obtained without careful... 

The chemical system and the final molded product requirements determine machinery requirements. Features to review in specifying equipment based on requirements to produce products includes the addition of a third and fourth component coloring paste in order to mold colored products. Many machinery suppliers offer color-dosing units in conjunction with a three or four component mixing head as auxiliary equipment. Clamps come in a variety of shapes and sizes most are custom-built. A clamp should have a smooth action through its... 

Rotational Molding. The process of rotational molding is ideal for creating hollow parts. Polyethylene is the most common polymer used in rotational molding. Powdered plastic is introduced into a clamshell mold. Color and additives, usually a micro-pulverized blend, are added and the mold is closed. The mold is then rotated. The powder is distributed to the mold s surface by the centrifugal force. The mold is heated and a melt skin forms on the mold s surface. Spinning continues as the mold is allowed to cool. The mold is then opened, the part removed, and the process starts again. 

As a new class of compounds, ester-amide based polymeric dyes do not benefit the formulator with a wealth of background information on the use of additives to enhance performance. The purpose of this paper is to explore the use of several wax additives in improving the residual haze of PP moldings colored with polyester-amide based polymeric dyes. 

The economics of recycling PET are more favorable than recycling HDPE. To iacrease the recycling of HDPE, the separation of bottles made of these two plastics could be omitted and a mixture processed. Coarse, light-colored powders of the two polymers have been prepared by an experimental soHd state shear extmsion pulverization process (55). The powder has been successfully injection molded without pelletization. 

Processing. SAN copolymers may be processed using the conventional fabrication methods of extmsion, blow mol ding, injection molding, thermoforming, and casting. Small amounts of additives, such as antioxidants, lubricants, and colorants, may also be used. Typical temperature profiles for injection mol ding and extmsion of predried SAN resins are as follows (101). 

Nonnutrient Additives. Nonnutritional dietary additives provide antioxidants to preserve freshness, flavor enhancers to stimulate food selection, color to meet the owner s expectations, pellet biaders to minimi2e fine particles, mycostats to minimi2e mold growth, and iagredient-flow enhancers. Pet foods do not iaclude coccidiostats, antibiotics, added hormonal materials, and fly-larval iasecticides used ia other animal feeds. 

Red Phosphorus. This aHotropic form of phosphoms is relatively nontoxic and, unlike white phosphoms, is not spontaneously flammable. Red phosphoms is, however, easily ignited. It is a polymeric form of phosphoms having thermal stabiUty up to ca 450°C. In finely divided form it has been found to be a powerful flame-retardant additive (26,45—47). In Europe, it has found commercial use ia molded nylon electrical parts ia a coated and stabilized form. Handling hazards and color have deterred broad usage. The development of a series of masterbatches by Albright Wilson should facihtate further use. 

C. V. Boys, Soap Bubbles Their Colors and the Forces Which Mold Them, Dover Pubhcations, New York, 1959 originally pubhshed by the Society for Promoting Christian Knowledge, London, 1890. 

The diisobutyrate ester of trimethylpentanediol is an economical, low color primary plasticizer for use ia surface coatings, vinyl flooring, moldings, and other vinyl products. This diester is commercially available from Eastman as Kodaflex TXIB plasticizer (49). 

Composites. The history of phenoHc resin composites goes back to the early development of phenoHc materials, when wood flour, minerals, and colorants were combined with phenoHc resins to produce mol ding compounds. In later appHcations, resin varnishes were developed for kraft paper and textile fabrics to make decorative and industrial laminates. Although phenoHcs have been well characterized in glass-reinforced composites, new developments continue in this area, such as new systems for Hquid-injection molding (LIM) and sheet-molding compounds (SMC). More compHcated composite systems are based on aramid and graphite fibers. 

Gel coats are pigmented polyester coatings appHed to the mold surface and are an integral part of the finished laminate. Gel coats are used widely on hand lay-up and spray-up parts to enhance surface aesthetics and coloration as weU as to provide an abrasion-resistant waterproof surface that protects the underlying glass-reinforced stmcture. 

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