avalon08 Jan 28, 2022:

I came across this entry searching for the correct English term for 共生地. I think 'common materials' not only doesn't explain but may also be misconstrued. I found this entry in Weblio, and it suggests "same fabric", which makes more sense:
ボタン１０の本体１２は、アクリル板１８以外の熱可塑性樹脂でも良く、共生地１４も熱可塑性樹脂の繊維であればよい。
A main body 12 of the button 10 may be made of a thermoplastic resin other than the acrylic plate 18, and the same fabric 14 may be made of a thermoplastic resin fiber. - 特許庁

Steven Smith (asker) Jan 22, 2008:

If it is 'common material', I don't see what this adds to the explanation, unless it means 'a material with common constituents', i.e a polymer resin of the same family but not identical. Or perhaps 'from the same batch'. This isn't elaborated on elsewhere in the text.