American Express Co. has introduced purchasing card software that helps  companies buy supplies on the Internet. 
The product, AXI Purchasing Solutions, is meant to spur the use of on-  line catalogues and paperless purchasing. 
  
American Express said only a handful of the nearly 1,000 corporations  using its purchasing cards are paying for products on-line. Many that place   orders on the Internet still pay the old-fashioned way.   
The card company said the software needed to process entire transactions  on-line has been developed only recently and should prompt companies to   automate purchasing.   
  
Internet-based systems save money, according to American Express, and  help employees comply with corporate purchasing rules. 
In April, three companies that supply this kind of automation software-  Ariba, Commerce One, and Concur Technologies-agreed to make their systems   compatible with American Express purchasing cards.   
Last month, three more companies signed on: Intelisys, Remedy, and  Tradex Technologies. 
  
Melissa Abernathy, an American Express spokeswoman, said these vendors  used to assume that "an order would be placed on-line but not the payment." 
American Express' product, which is operable with other software, offers  more purchasing information than competing systems, Ms. Abernathy said. The   company's relationships with 50,000 vendors of business-to-business   services also give it greater access to transaction data, she said.     
Other purchasing card issuers have similar programs and partnerships. GE  Capital, for example, has a relationship with Commerce One of Walnut Creek,   Calif. American Express is "a very early leader in this market," said Tom   McCleary, director of partnership relationships for Commerce One.     
American Express has been working since 1995 with companies that buy  supplies on-line. To help clients make the transition to electronic   purchasing, it formed marketing alliances with prominent on-line vendors   like Staples Inc., Office Depot business service division, and   Barnesandnoble.com.