After completing a Bachelor of Science (BSc) in New Zealand Thomas Athol Pressley joined a tannery in the United Kingdom as Works Chemist (1938). In 1943 he joined the British Leather Manufacturers Research Association in London and five years later was transferred to Sydney. The following year in 1949 he joined the Division of Industrial Chemistry at the CSIRO (Commonwealth Scientific and Industrial Research Organisation). Later the division was restructured and became the Division of Protein Chemistry. It was at this time that Pressley began to work on wool processing and utilisation.

He spent a lot of his time trying to solve problems in the health industry. One of his first collaborative successes was the production of a neutral detergent to be used in the blanket boiling sterilisation process used by hospitals. The product marketed as "Softly" became a household name. He also developed sheepskin underlays for hospital beds. Next Pressley moved his attention to the flammability of children's clothing. This was a collaborative project with the Burns Research Unit at the Royal Children's Hospital and the National Safety Council.