2912 Aldehydes, whether or not with other oxygen function, cyclic polymers of aldehydes, paraformaldehyde

2912 (01/1988-..) Aldehydes, whether or not with other oxygen function, cyclic polymers of aldehydes, paraformaldehyde 29121100 (01/1988-..) Methanal `formaldehyde` 29121200 (01/1988-..) Ethanal `acetaldehyde` 29121300 (01/1988-12/2006) Butanal `butyraldehyde, normal isomer` 29121900 (01/2012-..) Acyclic aldehydes, without other oxygen function (excl. methanal [formaldehyde] and ethanal [acetaldehyde]) 29121910 (01/2007-12/2011) Butanal `butyraldehyde, normal isomer` 29121990 (01/2007-12/2011) Acyclic aldehydes, without other oxygen function (excl. methanal [formaldehyde], ethanal [acetaldehyde] and butanal [butyraldehyde, normal isomer]) 29122100 (01/1988-..) Benzaldehyde 29122900 (01/1988-..) Cyclic aldehydes, without other oxygen function (excl. benzaldehyde) 29123000 (01/1988-12/2011) Aldehyde-alcohols 29124100 (01/1988-..) Vanillin `4-hydroxy-3-methoxybenzaldehyde` 29124200 (01/1988-..) Ethylvanillin `3-ethoxy-4-hydroxybenzaldehyde` 29124900 (01/2012-..) Aldehyde-alcohols, aldehyde-ethers, aldehyde-phenols and aldehydes with other oxygen function (excl. ethylvanillin `3-ethoxy-4-hydroxybenzaldehyde` and vanillin `4-hydroxy-3-methoxybenzaldehyde`) 29125000 (01/1988-..) Cyclic polymers of aldehydes 29126000 (01/1988-..) Paraformaldehyde