Pelletization liquid color concentrate

In dust-free and dispersed form, they are supplied as concentrated plastic granules (masterbatch pellets), as concentrated pastes, and as liquid colors. These products are added at different stages in the processing of plastics. 

Color Concentrate A colorant system where colorants and additives are compounded into a binder material. These can be in the form of pellets, coarse powders, granules, liquids, or pastes. 

Liquid colors are compatible with a wide variety of polymers, including PVC, polyethylene vinyl acetate (EVA), nylons, PET, polycarbonate, alloys, high-temperature polymers, and the full range of polyolefins and styrenics. Many liquid colors are suitable to color food-contact polymers and comply with all government regulations worldwide for shipping, use, and disposal. Lead times for liquid color are typically less than those for pellet or other melted color concentrates, since the processing is quick and efficient. 

Figure 20.4. Common methods of coloring plastics (a) 100 pellets of natural regin (b) liquid color on pellets (c) 4% pellet concentrate (d) excess of dry color.

Colorants come in several forms including liquids and dry concentrates. Color concentrates are typically used at a level of 3-4 percent. They are available in several forms including pellet, dice, chip, granular, or strand. The selection of the proper... 

Companies will custom formulate colorant and additive products designed to be used by plastic molders, who will, in turn, produce the final consumer products. The raw materials for colorant and additive products may be in powder, liquid, or solid form. The products formulated from them may also be in powder, liquid, or solid form. Dry color formulations (powder form) currently comprise less than 5% of the total colorant and additive products being produced today. Liquid formulations account for another 5% however, this form of product is increasing in popularity and is expected to capture a larger share of the colorant and additives market in the near future. The solid form, known as concentrates or masterbatch products, are concentrated ingredients encapsulated in a carrier resin that is usually in pellet form. This type of product comprises the overwhelming majority of the formulated products used by molders and compounders today. A discussion of the basic production processes associated with the production of the various colorant and additive product types is presented below. 

The reaction flask is allowed to cool and is then immersed in an ice-watcr bath. A solution of 160-180 g. (4 4.5 moles) of sodium hydroxide pellets in 500 ml. of water is added slowly with stirring until the pH rises to 5. After the addition of400 ml. of ether, the products are transferred to a 5-1. separatory funnel and then shaken. I he darkly colored organic upper layer is separated and the aqueous layer extracted with two 500-ml. portions of ether. The combined ether extracts are dried over anhydrous magnesium sulfate and concentrated to about 800 ml. under reduced pressure in a rotary evaporator. The concentrated extract is transferred to a 1-1. round-bottomed flask and fractionated through a 25-cm. Vigreux column under reduced pressure. A forerun of dioxane is collected and then tctrahydro-4H-pyranc-4-onc distils as a colorless liquid, b.p. 59 60°/l3 mm. The yield is 102 112 g. (50 55%) for the two steps, based on 3-chloropropionyl chloride. 

The physical form of the compound or concentrate and equipment used in manufacturing colored plastic objects can vary. Color houses can provide liquid, powdered, or pelletized systems that can be converted using all types of equipment (media mills, extruders, continuous mixers). The functions and equipment typical of a color house are detailed in the following. 

---