As filed with the Securities and Exchange Commission on December 19, 2023 Registration No. 333-275696 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 AMENDMENT NO. 1 TO FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 NANOPHASE TECHNOLOGIES CORPORATION (Exact name of registrant as specified in its charter) 1319 Marquette Drive Romeoville, Illinois 60446 (630) 771-6708 (Address, including zip code, and telephone number, including area code of principal executive office ...

Registration No. 333- As filed with the Securities and Exchange Commission on November 21, 2023 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 NANOPHASE TECHNOLOGIES CORPORATION (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorporation or organization) Delaware 3390 36-3687863 (Primary Standard Industrial Classification Code Number) (I.R.S. Employer Identification Number) 1319 ...