2-Hydroxy-9H-thioxanthen-9-one, commonly known as 2-Hydroxythioxanthone (ITX), is a specialty chemical serving primarily as a photoinitiator in UV-curable formulations. It is extensively used in the production of printing inks, coatings, adhesives, and overprint varnishes, promoting rapid free-radical polymerization upon exposure to ultraviolet light. This enables efficient curing processes in industries including packaging, graphics arts, electronics, and textiles. Additionally, it acts as an intermediate in organic synthesis for dyes, pigments, and certain pharmaceutical compounds, and supports research in photochemistry, material science, and organic semiconductors.