Actinic ink

Does anybody how can I improve the solubility of the Actinic ink?. I
am a paper conservator at the Archivo Historico Nacional at Madrid.
Our chemist and I have found out some problems with this ink:
although we shake it very well it looks to remain thick and it fills
our stamps so we can not get a *clear* stamping on the paper. Does
anybody knows how can we solve this problem?. If not so, does
anybody the address of the company so we can ask them?.

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                  Conservation DistList Instance 11:92
                  Distributed: Thursday, May 14, 1998
                       Message Id: cdl-11-92-022
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