German brand Walter Knoll showed a selection of new products during this year's imm Cologne furniture fair, including a chair designed by Foster + Partners (+ slideshow).

The London-based architecture firm created an upholstered dining chair entitled Foster 525. It features two slender panels instead of legs, and these extend upwards to form armrests. The firm previously designed a backless leather sofa for the company in 2009.

Also on show were several new versions of chairs first created by Turkish designer Sadi Ozis. The Fishnet chair – originally made from net woven between a steel framework in 1959 – features a bent petal-shaped chair and back, resting on slender metal legs.

The Burgaz chair has also been re-released, with an upholstered seat replacing its original woven seat, alongside an updated version of the Rumi chair, which features a half-moon-shaped cutout in the backrest.

Other furniture presented at the fair included pieces from Walter Knoll's Classic Edition range, which encompasses updated versions of historic products, launched to mark the company's 150-year-anniversary last year.

These included a new version of the 375 armchair, originally released in 1957 and described by the company as "not a chair for lolling around, but taking a seat". Walter Knoll's in-house design team has also created a new range of marble-topped tables, designed to accompany the chairs.

Other reissues include the Votteler chair, created by German designer Arno Votteler in 1956. The furniture rests on a tubular steel framework, and features armrests made from triangular panels of solid wood.

Walter Knoll has also added a new sofa and armchair to its Isanka range, created by Austrian design firm EOOS, and new editions of its Liz range of chairs, including woollen fabric with metallic threads, and a leather covered version.

This year's imm Cologne ran from 18 to 24 January. German furniture manufacturer Thonet also debuted new editions of classic furniture at the fair, showing outdoor versions of its Bauhaus chairs.