I purchased this dress at a thrift store the other day, believing it to be possibly 1960s? The zipper is metal, marked Japan.. it has a single size tag marked “8”, and a single tag marked “Oniell”.. no care instructions. The material feels like possibly nylon? The top of dress is lined while the rest is not. I couldn’t find anything similar on label or maker.. if anyone has any info I’d really appreciate it! Thank you!
I did find that YKK introduced the Conceal zipper in 1958. Hopefully, others will have more information for you!
Wonder if related to the O'Neill surf brand? I saw a logo of theirs with a mermaid that has a very similar font, except it has a proper upper case "E", not the rounded version here. However, some of their other logos (in a different font) show a similar rounded e amongst the upper case rest of the name. Anyway, may be something to go on!