The Wimbledon, London-based business, which was founded in 1896, said it will use the fund to enable it to "react quickly" to opportunities in the market, such as the purchase of equipment from failed printers.
Purbrooks chairman Martin Stern said that the company had already used some of the money to invest in new servers and to buy additional storage space.
"We are looking at investing in finishing and additional digital kit at present; essentially this fund is about making investments that add value to the business," he added.
Lender RBS has come under fire recently for shrinking its loan book to small businesses, however Stern said that the bank had been "brilliant", building further on a 60-year relationship with the printer.
Andy Rogers, relationship manager at RBS, said: "Purbrooks is a highly efficient printing company that has banked with us for many years.
"We have always worked closely with Martin and his team, keeping in close dialogue so that we can support their business plans as they grow and change."