The 1960s throughout the 1960s
Synthetic-Blend Easy-Care Construction
Building a garment around a wash-and-wear synthetic knit meant fewer internal layers, less structural support, and almost no ironing - a quietly significant shift in how much labor a finished garment actually demanded of the woman wearing it.
Building a garment around a stiff, shape-holding synthetic knit like crimplene changes more about actual construction than the fabric choice alone might suggest. A double-knit synthetic holds its own shape and resists wrinkling well enough that a lot of the internal structure a natural-fiber garment traditionally needed - interfacing to stiffen a collar or waistband, careful pressing at every stage of construction, a separate lining to keep a woven fabric from clinging or showing seam allowances through - can simply be left out. The fabric is doing structural work on its own that used to require a dressmaker's extra construction steps.
That reduction shows up clearly in finished garments from this period: fewer visible construction layers, simpler seam finishing since synthetic knits fray far less than woven natural fibers, and a general lightness of build that made mass manufacturing faster and cheaper at real scale. It's also, I'd argue, one of the more genuinely feminist pieces of construction history in this whole project, even though it rarely gets framed that way - a garment built this way needed dramatically less maintenance labor from the woman actually wearing it, no ironing after every wash, no dry cleaning, no careful hand-pressing to keep it looking presentable, at almost exactly the moment more women were working full-time outside the home and had measurably less unpaid domestic labor time to spend on wardrobe upkeep.
I think it's worth naming this as its own construction philosophy rather than treating "easy-care" as a marketing phrase layered onto ordinary garment-making, because it really did change what a garment's construction needed to accomplish. A dress no longer had to be built to survive careful, skilled maintenance - it had to be built to survive a home washing machine and require none. That's a genuinely different design brief than dressmaking had worked from for most of its previous history, and this decade is where it becomes the ordinary default rather than a novelty.