The most common and most likely answer to this crossword clue is the 7 letter word ACETATE
I've seen this crossword clue in Independent
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More clues leading to the result ACETATE
- Transparency shown by excellent gallery
- Synthetic textile in a church gallery
- Artificial fibre in church gallery
- Expert manufacturer of sugar and salt
- Top quality gallery material used in plastics
- Film shown in great exhibition space
- One swallowing tablet and rubbish synthetic material
- Salt in wonderful starter of tabbouleh getting consumed
- Synthetic fabric in fantastic gallery
- Recording star brought to gallery
Buddy explains!

The straight part
We know that "material used in plastics" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case material used in plastics = acetate.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does ACETATE mean?
ACETATE noun- Any salt or ester of acetic acid.
- Cellulose acetate.
- A transparent sheet used for overlays.
- Ellipsis of acetate disc: a disc of aluminium covered in a wax used to make demonstration copies of a phonograph record.