Leslie Fay Cardigan

I first thought this sweater was 1980s, considering the shoulder pads and boxy cut. However, the International Ladies Garment Workers Union label is black with the CIO change and a Rights Reserved “R” to the left of the symbol. According to Sammy D Vintage, this was only used until 1973, when the union started it’s “Look for the Union Label” Campaign.

The seems are machine serged, so that puts is post 1960s. Shoulder pads did have a brief life in the 1970s, but it wasn't until the 1980s and power suits that they really came back into fashion.

"Leslie Fay" was founded in 1947 by a clothing maker who produced clothes for men in the military, but after the war ended, began making women's clothing, the tag on this sweater is also very similar to a 1970s dress, but the design was still in use during the 80s. (Courtesy of the Vintage Fashion Guild)

The Leslie Fay line was created for and marketed to sophisticated women who wanted "wearable, flatting clothes that paid little attention to the youthquake." (1.)

I'm guessing 70s or 80s.

1. Milbank, Caroline Rennolds. New York Fashion: The Evolution of American Style. New York: Abrams, 1996. Print.