Given the following context:

Portrait of Monsieur Bertin is an 1832 oil on canvas painting by Jean-Auguste-Dominique Ingres. It depicts Louis-François Bertin (1766–1841), the French writer, art collector and director of the pro-royalist Journal des débats. Ingres completed the portrait during his first period of success; having achieved acclaim as a history painter, he accepted portrait commissions with reluctance, regarding them as a distraction from more important work. Bertin was a friend and a politically active member of the French upper-middle class. Ingres presents him as a personification of the commercially minded leaders of the liberal reign of Louis Philippe I. He is physically imposing and self-assured, but his real-life personality shines through – warm, wry and engaging to those who had earned his trust.
The painting had a prolonged genesis. Ingres agonised over the pose and made several preparatory sketches. The final work faithfully captures the sitter's character, conveying both a restless energy and imposing bulk. It is an unflinchingly realistic depiction of ageing and emphasises the furrowed skin and thinning hair of an overweight man who yet maintains his resolve and determination. He sits in three-quarter profile against a brown ground lit from the right, his fingers are pronounced and highly detailed, while the polish of his chair reflects light from an unseen window.
Ingres' portrait of Bertin was a critical and popular success, but the sitter was a private person. Although his family worried about caricature and disapproved, it became widely known and sealed the artist's reputation. It was praised at the Paris Salon of 1833, and has been influential to both academic painters such as Léon Bonnat and later modernists including Pablo Picasso and Félix Vallotton. Today art critics regard it as Ingres' finest male portrait. It has been on permanent display at the Musée du Louvre since 1897.

answer the following question:

What is the full name of the private person? 

Louis-François Bertin