Some reproductions are better than originals. Take the famous stacking “Panton chair.” Advances in the plastics industry have led to chairs of better quality than the originals. Danish designer Verner Panton (1926-1998) came up with the idea for the very first single-molded plastic chair in 1959-60. Vitra, headquartered in Basel, Switzerland, produced a polyurethane hard-foam version for Herman Miller in the late 1960s. Vitra switched to injection-molded thermoplastic construction in the early 1970s, then stopped production in 1975. Growing interest in mid-century modern design led Vitra to reintroduce the chair in the 1990s. Now it’s made of reinforced polypropylene, a tough, matte-surfaced plastic that can be dyed all the way through. A new chair sells for about $250 and is available in several colors.