HPMCP is a monophthalic acid ester of hypromellose
Since the introduction of HPMCP (hypromellose phthalate USP/NF, JP, EP) in 1971, it has proved its value in enteric coating using organic solvent. The chemical structure of HPMCP is a monophthalic acid ester of hypromellose.
The threshold pH value for rapid disintegration of HPMCP can be controlled by varying the phthalyl content. Two types of HPMCP with different in pH-solubilities, HP-55 and HP-50, are available. Moreover, HP-55S, a special type of HP-55, which is distinguished by its higher molecular weight, greater film strength and higher acid resistance properties, has also been introduced. A suitable grade of HPMCP for a particular purpose should be selected in accordance with each preparation.
Application of HPMCP and SmartEX® in the development of MUPS-ODT for Lansoprazol 15 mg [H-020, SE-007]
Application of HPMCP in extended release matrix tablet formulation [H-023]
Application of HPMCP in the development of rabeprazole sodium delayed release tablet by organic enteric coating [H-022]
Dissolution behavior of coated fine particles by aqueous and solvent coating [A-045, H-013]
Enteric coating of hard gelatin capsules using HPMCP [H-006]
Enteric coating of soft gelatin capsules with HPMCP [H-018]
Film solubility of mixed HPMCP [H-011]
HPMCP - typical coating conditions for tablets (1) [H-002]
HPMCP - typical coating conditions for tablets (2) [H-003]
HPMCP - typical coating conditions for tablets [H-001]
Hydrolysis of HPMCP in ethanol-water solution [H-005]
IR spectrums of HPMCP and Shin-Etsu AQOAT® [H-017, A-054]
Itraconazole 65 mg capsule using HPMPC-50 by solid dispersion approach [H-021]
Residual solvent in ethanol/water HPMPC-55 tablet coating [H-007]
Solubility of HPMCP in mixed organic solvents [H-010]
Solution preparation of HPMCP and Shin-Etsu AQOAT® (HPMCAS) [H-019, A-058]
Stability of HPMCP coated tablets [H-015]
Stability of HPMCP under humid storage conditions [H-016]
Grades and applications
Application
Tablets & Pellets
Taste masking by coating with enteric polymer and pore former
Enteric/delayed release coating (solvent)
Amorphous Solid Dispersion (ASD)
Solvent free methods (HME)
Solvent methods
Continuous Manufacturing (CM) for Oral Solid Dosage Form (OSD)
Enteric/delayed release coating
Amorphous solid dispersion (ASD)
HPMCP
All Grades
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• Suitable / •• Very Suitable
History of HPMCP (Hypromellose phthalate) at Shin-Etsu
Shin-Etsu was established in 1926 in Japan and employees more than 20 thousand people worldwide. Since the introduction of HPMCP (hypromellose phthalate USP/NF, JP, EP) in 1971, it has proved its value in enteric coating. HPMCP is a versatile coating material, it can be used for the enteric coating of tablets, pellets and capsules.
The enteric coating was developed in the 1940s to act as a barrier to protect drugs with low acidic stability from degradation by gastric acid or to protect gastric mucosa from irritating drugs. Moreover, it allows to deliver drugs optimally absorbed in the small intestine in a most concentrated form in this specific region of the digestive tract. HPMCP is also suitable for solid dispersion technologies.
General Product Information
HPMCP as enteric coating agent is insoluble in acidic environment like in gastric juice but dissolves immediately after the transfer of enteric coated tablets to the small intestine, as example. It is prepared from highly purified pulp, a widely distributed natural material, in our manufacturing site in Japan. The product is packed in 25 kg fibre drums with double polyethylene inner bags.
The chemical structure is a monophthalic acid ester of hypromellose dissolving easily in different organic solvents into a clear solution whereas the most recommended solvents to be used are ethanol/water or isopropanol/water combinations. The enteric coating solutions can be applied on tablets, capsules or pellets.
Solvent Systems for HPMCP
Organic solvents
HP-55 / HP -55S
HP-50
Acetone
S
P
Acetone / Water (95:5)
S
S
Acetone / Ethanol (1:1)
S
S
Dichloromethane /Ethanol (1:1)
P
P
Dioxane
S
S
Methanol
P
P
Isopropanol
P
I
Ethanol
I
I
Ethanol / Water (8:2)
S
S
S = soluble, P = Partly soluble, I = insoluble
The film obtained with HPMCP is showing very good mechanical properties and mostly no plasticizer is needed in the formulation.
pH dependent disintegration of HPMCP
The threshold pH value for rapid disintegration of hypromellose phthalate can be controlled by varying the phtalyl content on the hypromellose backbone. HPMCP contains a carboxyl (phtalyl) group but its backbone structure is a water-soluble polymer. The phthalyl group defines the soluble nature of HPMCP, which is insoluble in water due to its hydrophobicity and soluble in weak acid to neutral medium.
Two types of HPMCP with different pH-solubilities, HP-55 and HP-50, are available. HP-50 disintegrates at pH 5.0 and HP-55 at pH 5.5 respectively. Moreover, HP-55S, a special type of HP-55, was introduced which is distinguished by:
higher molecular weight
greater film strength
higher acid resistance properties.
An appropriate grade of HPMCP for particular purposes should be selected application-specific.
Product name
Compendial name
Grade
Dissolving pH
Typical application
HPMCP
Hypromellose Phtalate
(NF, PhEur, JP)
HP-55
≥ 5,5
Regular grade
HP-55S
Greater film strength
HP-50
≥ 5,0
Soluble at lower pH
HPMCP is well established in several pharmaceutical products going from proton pump inhibitors to antibiotics and enzymes in form of enteric coated tablets or pellets.
In the recent years, besides enteric coating and driven by the need of improving the solubility of active ingredients, HPMCP is used as matrix polymer for amorphous solid dispersion systems developments.
Shin-Etsu has more than 20 Technical documents available for HPMCP; such as:
The Shin-Etsu team is supporting in all technical, quality and regulatory related questions. Our team of sales and technical sales manager can help you to develop your products, or provide support during issues at your manufacturing process. Shin-Etsu has long year experience in cellulose ether business and is aiming to give you the best possible guidance and high quality products manufactured in Japan and Germany.
