SINGAPORE (BLOOMBERG) - Almost a decade ago, the son of Singapore paint tycoon Goh Cheng Liang set his sights on gaining control of Japan's biggest paint maker. He finally succeeded, and that's been a boon for the family's wealth. Their Wuthelam Holdings took a majority stake in Nippon Paint Holdings in a US$12 billion (S$16 billion) deal that was completed last month, according to filings this week. That's boosted their fortune to US$24 billion from about US$16 billion before the alliance was announced, according to the Bloomberg Billionaires Index. For years, Wuthelam and Nippon Paint operated a business with joint ventures in countries including China, India and Malaysia. In August, Nippon Paint struck an agreement that allowed them to buy out the joint venture and take over Wuthelam's wholly owned Indonesia business. In turn, the Gohs' increased their stake in Nippon Paint to about 58 per cent. "The growth will continue," said Bloomberg Intelligence analyst Horace Chan, who estimates the alliance could lift Nippon Paint's net income by about 64 per cent this year. "It will help the company in terms of simplifying the corporate structure, which will allow more efficient allocati...