In Riess v. Sanford (1941) 47 Cal. App. 2d 244, a former employee who had been entrusted with the employer's secrets made use of them. The Court of Appeal held: "No agent or employee having been entrusted in the course of his employment with secret and valuable information known only to his employer may thereafter utilize this secret knowledge against the interests or to the prejudice of his employer. This principle is well stated in 28 Am.Jur. 304, as follows: 'The disclosure by an employee of trade secrets and other confidential information obtained by him in the course of his employment is a breach of trust, and it is well settled that a court of equity will restrain any threatened disclosure or use thereof to the detriment of the employer. . . .'" ( Id. at p. 246, )