$0Japan 's Hoya Corp. has announced that it will spend about 13 million JPY (146 million USD) to open a glass substrate plant in Vietnam in 2011. $0 $0 Part of the Japanese company’s efforts to meet strong demand from hard drive makers, the plant, to be built in the Hanoi-based Thang Long Industrial Park , will have an estimated capacity of 12 million units of product per month, the company said. $0 $0 Once the factory reaches its full capacity in the autumn of 2011, Hoya Corp's total production capacity for hard drive material will be equivalent to 52 million 2.5-inch units per month, up 70 percent from the present level, the company said. $0 $0 The company has set up glass substrate plants in the Philippines , Thailand and China . It also plans to open a second Philippine factory in the autumn, with a monthly capacity of 10 million units of product, boosting the firm's overall capacity by over 30 percent to roughly 40 million units of product. $0 $0 Currently, Hoya Corp. controls more than 60 percent of the global market for glass substrates for hard drives./.$0