Carrageenan is that the carrageenan is first dissolved and filtered to remove cell wall debris. The carrageenan is then precipitated from the clear solution either by isopropanol or by potassium chloride. A hybrid technology in which seaweed is treated heterogeneously as in the semirefined process exists, but alcohol or high salt levels are used to inhibit dissolution. This process is often used on South American seaweeds and gives some of the cost benefits of semirefined processing, while allowing a wider range of seaweeds to be processed, however, the naturally low cellulose levels in some South American seaweeds allow them to be
Purple Renaissance was made from the wood of the logwood tree (H"aematoxylum campechianum"), which grew in Spanish Mexico. Depending on the different minerals added to the dye, it produced a blue, red, black or, with the addition of alum, a purple color, It made a good color, but, like earlier dyes, it did not resist sunlight or washing. In the 18th century, chemists in England, France and Germany began to create the first synthetic dyes. Two synthetic purple dyes were invented at about the same time. Cudbear is a dye extracted from orchil lichens that can be used to dye wool