SEOUL — Life has been a roller coaster for Kim Yong-chul since he began talking about Samsung Electronics two and a half years ago. He has been celebrated by some as a whistle-blower, but in a culture that emphasizes workers’ loyalty to their employers, he has also been vilified as a traitor driven by personal grudges.

That was before Mr. Kim’s 474-page exposé, “Think Samsung,” hit stores in February.

The book makes sensational allegations of extensive corruption by Lee Kun-hee, the richest man in South Korea and the chairman of Samsung Electronics, the world’s largest technology company by revenue.

Samsung is the most sacrosanct — and yet often mistrusted — company in South Korea. Since the book’s release, the country’s major newspapers and Web sites have refused to carry advertisements for it, and few South Korean publications have reviewed it. One newspaper reported on its popularity — it became a best seller, thanks to strong word of mouth on blogs and Twitter — but did not print its title or detail its allegations.

“Isn’t this a comedy?” Mr. Kim, 52, said in an interview. “I am challenging them to slap my face, to file a libel suit against me, but they don’t. They treat me like a nut case, an invisible man, although I am shouting about the biggest crime in the history of the nation.”