Tea pigments, are you referring to tea polyphenols?
The process of extracting tea polyphenols is: the tea leaves are refluxed and extracted with 75%-80% ethanol three times, each time for 1-1.5 hours. The filtrate is centrifuged, and the obtained clear liquid is directly passed through the macroporous adsorption resin, and Elute impurities with deionized water, then elute with 60-70% ethanol, concentrate the ethanol solution, and spray-dry to obtain it.