ART MARKET / A collector who backs his own hunches: Trends mean nothing to Robert Loder. Abstract Expressionism is his great love and he wants us to share it, as Geraldine Norman reports

WHAT HAPPENS to artists when their 'movement' goes out of fashion? The one or two who have achieved household-name status get treated as Old Masters, with travelling exhibitions and retrospectives. The rest find themselves ignored by critics and unpopular with smart commercial galleries who are caught up with newer trends. They are shunted into a backwater, invisible to the greater public, where they are supported by like- minded artists and collectors - to re- emerge decades later, if they are lucky, as rediscovered geniuses.

Remember Abstract Expressionism? Or Colour Field painting? They were movements that were at their peak in the 1950s and 1960s, but artists who fell in love with them then - or who caught up with them later - are still working in those modes today. Robert Loder, one of Britain's most offbeat private collectors, has been quietly amassing a large body of their work. His collection can be seen at the Atlantis Gallery in Whitechapel until 11 September under the title 'Lead and Follow: the Continuity of Abstraction'.

Loder hopes the exhibition will help set the rediscovery process in motion. He writes in the exhibition catalogue of the artists he admires who 'stand outside the current preoccupations of the contemporary art market, conscious perhaps that if you keep your old clothes long enough there will come a time when they emerge from the wardrobe enhanced by age, to delight another audience.'

Loder, a British businessman, is an art patron on Victorian lines - he has more in common with Prince Albert than with his contemporaries, notably a deep belief in the value of culture and an idealistic desire to help stimulate the process of creation.

He began conventionally enough. The son of the second Baron Wakehurst, he was educated at Eton and Cambridge then worked for the Anglo American Corporation in Johannesburg and Lusaka from 1957 to 1966. It was there he started to show his offbeat side. In Johannesburg he helped run Union Artists, a black theatre group that played to mixed audiences in the heartland of apartheid. And in 1959 he founded the African Arts Trust, which assists black artists from South Africa.

On his return to London, Loder became treasurer, then chairman, of the Institute of Contemporary Arts. Meanwhile, backed by his friend Lord Rothschild, he built up a business with offices in 30 countries and 2,000 employees. Since 1982, he has been executive chairman of Curtis Brown, the literary agency. He treats the chairmanship with agreeable informality, as I discovered when I went to discuss his art collection - he makes his own cups of tea and has no secretary. His bookshelves groan with catalogues of exhibitions he has helped to mount.

Loder's first foray into art was to form a vast collection of British prints. 'I regarded it as a way of learning about painting,' he says. He amassed several hundred, dating from 1790 to 1930, which were shown at the Fitzwilliam Museum in Cambridge in 1985 and then sold to the Koriyama City Museum of Art in Japan. That left him free to concentrate on contemporary painting and sculpture.

Loder's mentor in this field is the sculptor Anthony Caro, one of the very few British abstract artists who have successfully broken into the 'Old Master' category. They met in 1980, when Caro was trying to tour an exhibition of British abstract art in South African townships. They found they were 'kindred spirits' Loder says. The following year, when staying in New York State, they developed the idea of running workshops for professional artists. The first Triangle workshop - so called because the artists were American, Canadian and British - was held in 1982. The workshops became an annual event, and Loder subsequently helped organise similar workshops in South Africa, Zimbabwe, Botswana, Mozambique, Zambia, Jamaica, Namibia, and from 1990 at Shave Farm in Somerset.

Loder points out that the works he is showing at the Atlantis Gallery do not constitute a collection in the conventional sense of carefully selected paintings bought from galleries. 'Nearly all the paintings were bought from the artists themselves,' he says.

The sculpture tends to look a bit like Caro even when it is by other sculptors. There is a good Caro of 1981, a 6ft Bronze Screen, but Loder has also bought pieces by younger artists such as Andrew Sloan and Clay Ellis who also work in welded steel. And there's a big ladder-shaped wooden structure called Mull by the American artist, Willard Boepple.

The key note for the paintings collection is provided by John Hoyland and Basil Beattie, both survivors from the heroic days of the Sixties, when their work was at the forefront of the British avant-garde. Loder has also sought out works by Hoyland's friend Brian Fielding, who died in 1987.

To make his collection more comprehensive, Loder has bought at auction works by the British pioneers Bryan Winter, Terry Frost and Alan Davie; he has also extensively patronised the middle generation: artists who kept the flame of abstraction alight in studios in Greenwich - Geoffrey Rigden, Mali Morris, Geoff Hollow and Clyde Hopkins - and bought works by their friend Fred Pollock. He is keen to encourage young artists, too; the youngest is Rebecca Fortnum, 31.

In among the expressionists, there are also one or two exponents of cleanly controlled patterning who stand out: Yuko Shiraishi gives a hint of the Zen aesthetic of Japan while Callum Innes suggests that post-modernism may be taking abstraction down a different road altogether.

The real outsider, however, is the Westminster Study of 1987 by the Boyle Family, a corner of Westminster pavement and adjacent road, cast in glass fibre and carefully textured to imitate the original, yellow line and all. The Boyles' work is generally called 'realist' or 'conceptual' - but Loder is an old friend of Mark Boyle so he's decided the piece is an 'abstract' and deserves a place in his show.-