Sir Lionel Alexander Bethune Pilkington OBE FRS (7 January 1920 – 5 May 1995), always known as Sir Alastair Pilkington, was a British engineer and businessman who invented and perfected the float glass process for commercial manufacturing of plate glass.
Born on 7 January 1920 in Calcutta, India, he was the son of Colonel Lionel George Pilkington MC (1889–1955) and his wife Evelyn Carnegie Bethune (1892–1985), sister of Sir Alexander Maitland Sharp Bethune, 10th Baronet. He was educated at Sherborne School and Trinity College, Cambridge, where his studies were interrupted by the outbreak of World War Two. Joining the Royal Artillery, he was captured in the Battle of Crete and spent four years as a prisoner of war in Nazi Germany. Returning to university, he obtained an engineering degree, followed by a job with the glass manufacturers Pilkington Brothers. He was not related to the Pilkington family which then controlled the business.
In 1952 he invented the float glass process, in which molten glass was "floated" over a bath of molten tin and manipulated to achieve the required product thickness, and with his associate Kenneth Bickerstaff, spent seven years perfecting and patenting its commercially successful manufacture. American inventors had tried several times to achieve an improved and lower-cost process to replace the costly plate glass, but had not succeeded. His breakthrough enabled Pilkingtons to dominate the world market for high quality flat glass for many years. Starting in the early 1960s, all the world's leading flat glass manufacturers obtained licences to use the float glass process. From technical director of Pilkingtons in 1955, he became deputy chairman in 1971 and chairman from 1973 until he reached retirement age in 1980,leaving the board in 1985.  For the rest of his life he was the company's president.
Outside activities and honours
In 1969 he was appointed a Fellow of the Royal Society and in 1970 a Knight Bachelor, as well as receiving the Wilhelm Exner Medal. In 1978 he was awarded the A. A. Griffith Medal and Prize and in 1983-4 served as President of the British Association.
Outside directorships included appointments as a director of the Bank of England from 1974 to 1984 and a director of BP from 1976 to his death. A passionate advocate of tertiary education, he was from 1980 to 1990 Pro-Chancellor of Lancaster University, from 1990 Chairman of the Campaign for the University and Colleges of Cambridge and from 1994 to his death Chancellor of the University of Liverpool.
In 1945 in London he married Patricia Nicholls Elliott (1919–1977), a former WRNS officer who was the daughter of Rear-Admiral Frank Elliott OBE, and they had a daughter Rosalind together with an adopted son James. After his wife's death, in 1978 he married the American former radio actress Leila Kathleen Wilson (1911–2005), widow of Eldridge Haynes.
- Ancestry.com. England & Wales, Death Index, 1916–2007 [database on-line]. Provo, UT, USA (subscription required) Accessed 3 December 2015
- "Pilkington PLC biography - Sir Alastair Pilkington". pilkington.com. Archived from the original on 5 March 2007.
- "BBC - History - Sir Alastair Pilkington (1920–1995)". bbc.co.uk. Archived from the original on 13 January 2005.
- U.S. Patent 2,911,759 – Manufacture of float glass, issued 10 November 1959
- Pilkington, L. A. B. (1969). "Review Lecture. The Float Glass Process". Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences. 314 (1516): 1–25. doi:10.1098/rspa.1969.0212. JSTOR 2416528.
- Who's Who 1988
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- https://www.thegazette.co.uk/London/issue/35511/page/1512/data.pdf Accessed 3 December 2015
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