Crepe is a texture, which is probably best described as grainy, puckered or crinkled. The texture can be achieved by the type of fiber (especially hard or crepe twist yarns*, textured yarns), chemical treatment, textured weave, or embossing. It may be made of any fiber and may be woven or knit. The name comes from the French word for crimped, crêpe. A wide range of fabrics are crepes. See also: Chiffon Cloqué Crepe de chine Crepe-back satin Crepon Georgette Matelassé * Yarns used for the creation of fabric can be classified by the amount of twist in each yarn, from very low twist (3-5 turns per inch) to crepe twist (40-75 per inch). The texture of crepe yarns, when they go through a wet-finishing process, becomes uneven, and the fabrics made from these crepe fibers have a pebbled texture, good drapability, and a matte appearance. This is a rayon crepe Rayon crepe is beloved for having a spring-y give to it—like a subtle stretch—from the crepe-twist yarns. Those yarns have give the way curly hair has give; you can pull curls and see that the hair lengthens. Heather @Noble Vintage Clothier has a 40s rayon crepe dress. You can see the matte look from a distance, and up close ...there's that give-away texture. I don't know for sure, but anecdotally rayon crepe seems to have been most often used in the 40s. Worsted wool crepe Victoria @Vintagiality has a wool crepe dress. Again the close up shows the texture. A woven nylon with the crepe texture achieved by embossing Marsha @Ranch Queen Vintage has this polka dot blouse I've had my eye on forever. Again, the closer you view it the more you can detect that embossed crepe texture. This type of fabric (man-made fiber with an emboss) is most typically seen in the 1960s and 70s. Any thoughts or questions?
So was the lightweight wavy or crinkled texture poly we had for so many blouses & dresses back in the 70s actually a type of crepe - I think my Mom always called it "whipped creme" fabric. I also know I learned a very heartbreaking lesson early on in my vintage career ...water and rayon crepe DON'T mix - always dry clean (especially when it's lined).
Whipped Cream! That was a Dacron polyester that was being given the marketing treatment for sure. This is from 1964 1965 '66 It is a crepe, although I would probably call it a crepe emboss. Thank you for mentioning the shrinkage problem—that is so true, and such a painfully learned lesson!
A little more about Whipped Cream. The name seems to have stuck even post-Dacron and it looks like it was applied to polyester/acetate blends and other combos. It was to be washed and dripped dry which seems to have been a big charm. It shouldn't be ironed because the emboss can flatten.
I would certainly NEVER iron it (and I DID wear it alot back in the day)... that said; my Mom found that if it was tumble dried on a low heat with a large bath towel & them promptly hung up while still warm; it was what she thought was an "easy care" fabric back then.