can't read?
HPMCP is a monophthalic acid ester of hypromellose (hydroxypropyl methylcellulose), and the threshold pH value for rapid disintegration of HPMCP can be controlled by varying the phthalyl content.
H 1694 (OTTO) Hydroxypropyl methyl cellulose phthalate Cas 9050-31-1 - used as an enteric coating agent by the pharmaceutical industry.