Ken Ferguson has joined INX International Ink Co. as technical manager for distributors. With more than 25 years industry experience, he has assumed national responsibilities in his new position.     Mr. Ferguson comes to INX after spending the last 18 years at Van Son Holland Ink Corporation of America in New York. Over the years he worked in various capacities, most recently as technical director for the U.S., where he managed a team of technical service, lab specialists and administrative s...