Yuko Ishii, a 53-year-old factory worker in central Japan, used to feel reluctant about buying products made in South Korea. That changed after she became a fan of pop stars such as boy band TVXQ.

"I used to rule out Korean products, but now I have no problem with them," said Ishii, whose purchases include a washer made by LG Electronics Inc. "If my favorite star was advertising a South Korean TV, I would definitely buy it. I want to feel closer to them by buying the same products they use."

Ishii and other fans of so-called K-pop may help South Korean electronics makers expand in Japan, where consumers have traditionally preferred domestic brands.