Shin-Etsu Chemical Co., Ltd.

Fujio Sekigawa

Shigeru Ohno

Noboru Hoshi

Hiroyasu Kokubo

Yoshiro Onda

Tohru Chiba

Katsuyoshi Minemura

Shokichi Yamagishi

Masayuki Tonedachi

A coated solid medicament form suitable for oral administration having reliable releasability of the active ingredient only in the large intestine is proposed. The medicament form is prepared by coating a core solid medicament form containing the active ingredient first with a chitosan having a specific degree of deacetylation and a specific degree of polymerization and then top-coated with a specific enteric-soluble polymer which is a hydroxypropyl methyl cellulose acetate succinate or a hydroxypropyl methyl cellulose hexahydrophthalate. The releasability of the active ingredient only in the large intestine can be more reliable when the core medicament form is, prior to coating with chitosan, provided with an enteric undercoating layer.

Coated solid medicament form having releasability in large intestine

Film coated pharmaceutical preparations, which are prepared by overlaying to the outer surface of pharmaceutical preparations, a coating layer comprising at least one member selected from the group consisting of methyl cellulose, hydroxypropylmethyl cellulose, hydroxypropyl cellulose, hydroxypropylmethyl cellulose phthalate, hydroxypropylmethyl cellulose acetate succinate, carboxymethylethyl cellulose and cellulose acetate phthalate, are irradiated with light including ultraviolet rays. Whereby film coated pharmaceutical preparations, the coating layer surface of which are excellent in whiteness, are prepared. Moreover, as a content of a white pigment in corporated into the coating layer of such preparations may be reduced, the stability of such preparations can be enhanced without impairing the strength of the coating layer.

Method for preparing film coated pharmaceutical preparations and method

Instead of using a uniform aqueous solution of a water-soluble cellulose ether as a coating liquid of solid medicament forms, e.g., granules and tablets, to form a film-forming layer, an aqueous dispersion of a cellulose ether, which is soluble in cold water but insoluble in hot water, is used as a coating liquid at a temperature higher than the solubilization temperature, i.e. the critical point of the solubility behavior, followed by plasticization of the cellulose ether particles with water to cause fusion thereof. The coating liquid is freed from the limitation by the flowability even when the content of the cellulose ether is much higher than in the conventional solution-type coating liquid. In addition to the greatly decreased time taken for forming a coating layer in a desired coating amount, moreover, cellulose ethers having a high degree of polymerization, which cannot be used in the conventional method, can be used so that the resultant film-coating layer is much stronger than otherwise to provide a sustainedly releasing coating layer.

Method for the preparation of a coated solid medicament

The invention provides a novel method for providing entric coating on solid dosage forms using an aqueous coating liquid so that the problems inherent to the use of a coating liquid in an organic solvent can completely be eliminated. The inventive method comprises dispersing a finely divided powder of a hydroxypropylmethylcellulose phthalate in an aqueous medium containing triacetin to give an aqueous coating liquid with which the solid dosage forms are coated, for example, by spraying and dried. It is necessary that the preparation of the coating liquid and the coating procedure with the coating liquid are performed throughout while keeping the temperature of the liquid below 25.degree. C. so as that the particles of the hydroxypropylmethylcellulose phthalate are not dissolved in the medium forming a stable dispersion without adhesive coalescence.

Method for providing enteric coating on solid dosage forms

Solid pharmaceutical dosage forms of the sustained release type coated with a coating material composed of an aqueous dispersion of a high molecular weight organopolysiloxane and a water-soluble cellulose derivative in the absence of any organic solvent. The solid dosage forms have an excellent property of highly controllable sustained release in a wide range.

Sustained-release solid pharmaceutical dosage forms and preparation

Enteric coatings are provided on solid pharmaceutical dosage forms by a method comprising covering the dosage froms with an aqueous solution of a polymeric substance having carboxyl groups in the watersoluble salt form and contacting the thus coated dosage forms with an inorganic acid to convert the polymeric substance into the water-insoluble acid form. The coating solution includes no organic solvent, and this method is safe from dangers of fires or explosions and air pollution.

Method for providing enteric coatings on solid dosage forms

Methylcellulose with or without the addition of medically active ingredients and other additives is first granulated by a known method into granules of appropriate size and then the granules are blended with a disintegrator and compressed into tablets. The tablets obtained by the method have sufficient hardness and very short disintegration time when taken into the human body in comparison with the poor disintegrability of tablets directly shaped from powdery methylcellulose or a methylcellulose-based mixture of active ingredients. The method is useful for tableting some medicinals of poor tabletability, such as, pancreatin which require large amounts of a binder to be successfully shaped into tablets. Tablets of methylcellulose prepared in accordance with the method can find use as a non-caloried food.

Preparation of readily disintegrable tablets

Pharmaceutical solid dosage forms are covered with three successive layers of coating, consisting alternately of an undercoat composed substantially of a polymeric substance, a secondary coat composed substantially of a polymeric substance and a pigment, and a finish coat composed substantially of a polymeric substance. Application of these coatings produce economical advantages both in time and labor, and the surfaces of the coated dosage forms are smooth and glossy, and have no cracking.

Method of coating pharmaceutical solid dosage forms

When a mixture comprising 30 to 70% by weight of an enterosoluble cellulose derivative containing a monoester linkage with a polybasic acid, such as, hydroxypropyl methylcellulose phthalate, and 70 to 30% by weight of a digestive fluid-insoluble cellulose derivative, such as, ethylcellulose is used as a coating material for solid medicines, the rate of gradual release of active ingredients of the medicine in the intestinal tracts can be appropriately controlled.

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Omiya, Japan

Fujio Sekigawa