No. 77-1953. Submitted June 14, 1978. Decided July 26, 1978. James J. Salzman, Chicago, Ill., argued and on brief, for petitioner. Elinor Hadley Stillman, Atty., N.L.R.B., Washington, D.C., argued, for respondent; Marjorie S. Gofreed and Frank T. Mamat, Attys., John S. Irving, Gen. Counsel, John E. Higgins, Jr., Deputy Gen. Counsel, Carl L. Taylor, Associate Gen. Counsel and Elliott Moore, Deputy Associate Gen. Counsel, N.L.R.B., Washington, D.C., on brief. Petition for review, of National Labor