PARIS — Françoise Bettencourt Meyers, the granddaughter of L’Oréal’s founder, has applied to a guardianship judge here to obtain legal protection for her mother, Liliane Bettencourt. It is the latest news in an ongoing affair that pits Bettencourt Meyers against photographer François-Marie Banier. It began in December 2007, when Bettencourt Meyers lodged a complaint in the public prosecutor’s office of Nanterre, France, for “exploitation of weakness” of her mother. This followed Bettencourt giving Banier gifts of almost 1 billion euros, or $1.5 billion at current exchange. On Sept. 3, a preliminary hearing took place in Nanterre, and a second one is scheduled for Dec. 11.