VWR International Inc. of West Chester said today that it purchased the 76 percent stake in a German laboratory supplier it didn't already own for an undisclosed amount.

The German company, KMF Laborchemie Handels GmbH, has 70 employees and annual revenue of $45 million.

VWR, which supplies research laboratories, is privately held and employs 6,000. The company has revenue of about $3 billion a year.