DE1120635B - Process for the production of a coating film on tablets - Google Patents

Description

It is known in the tablet manufacturing art to apply liner coatings to coated or uncoated To apply tablets. In the case of uncoated tablets, the liner acts as a Protection against the dissolution of the tablet in the mouth, thereby avoiding the unpleasant taste usually associated with oral medications without disintegrating the Tablet, once it has left the oral cavity, is significantly delayed. In the case of one coated tablet, the film or lamination protects the tablet from the effects of moisture, without noticeably delaying their disintegration, and also provides a basis that is at the same time suitable for the formation of a strong gloss is suitable and also has an adhesive effect on any characteristic imprint.

So far it has been common to use shellac either directly or after modification as a laminating cover. Shellac does have some of the desired ones Properties, for example, it is resistant to the penetration of moisture, it fulfills however, not all of the requirements to be met by an ideal laminating cover. So shellac tends to Becoming sticky, causing conglomeration and deterioration in the appearance of each Tablets leads. In addition, the shellac does not offer a stable basis for information, as it usually does printed on tablets to indicate their origin and content. Because of its stickiness The shellac makes it difficult to handle the tablets, which increases the production costs Increase tablet.

The aim of the invention is a method for applying a lamination coating which has all the advantages stability, ease of application, adhesiveness for prints and the ability to to assume strong luster.

According to the invention this object is achieved in that resinous polymers of terpenes with a melting point in the range from 70 to 135 ° C can be used as a coating agent. The coating is applicable to any tablet suitable for pharmaceutical use. Such Coated tablets have all of the advantages mentioned above.

Resins with a melting point of below 70 ^° C. are not suitable for producing the film coatings according to the invention. They are too sticky and too slow to set to result in a smooth, glossy film. Resins with a melting point of over 135 ° C form films that are very brittle and tend to crack and splinter.

Method of manufacture
of a coating film on tablets

Applicant:

Olin Mathieson Chemical Corporation,
New York, NY (V. St. A.)

Representative: Dr.-Ing. H. Ruschke, Berlin-Friedenau,

and Dipl.-Ing. K. Grentzenberg,
Munich 27, Pienzenauer Str. 2, patent attorneys

Claimed priority:
V. St. v. America, February 27, 1959 (No. 795 916)

Harland E. Heilig, North Brunswick, N.J. (V. St. A.) has been named as the inventor

The resins of terpene polymers used according to the invention, which melt between 70 and 135 ° C, are described in U.S. Patent 2,335,912. You can by polymerizing / 3-pinene using aluminum chloride in an inert liquid reaction medium with stirring or Shake and be prepared with dissipation of the heat of reaction.

These resins have the advantage that they are physiologically inert, but insoluble in water and ethanol are soluble in the solvents mentioned below.

In contrast to this, mastic (Hager's Handbuch der Pharmazeutischen Praxis, 2nd supplementary volume, Pp. 1764 to 1767, Berlin, 1958) insoluble in the solvents that can be used for making films. In addition, it is pale yellow or green-yellow in color, smells of balsam, tastes turpentine-like and is therefore not suitable for pharmaceuticals.

Cellulose acetate phthalate (op. Cit.) Is in acetone or mixtures of ethyl acetate and isopropanol soluble; however, these solvents can be used far less easy to handle than the solvents given below for those used according to the invention Resins. Their disadvantages are based on their fire hazard and harmful health Effects that require specially designed ventilation systems. In addition, to achieve smooth films of cellulose acetate phthalate significantly

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more coatings are required than in the method according to the invention. Finally it has been shown that the for Cellulose acetate phthalate suitable solvent for the manufacture of colored tablets is not used because the dyes in question are insoluble therein.

The use of polymethacrylic acid resins (op. Cit.) For the production of a film for pharmaceutical tablets has the serious disadvantage that mixtures of acetone and Aiko- ίο hol must be used as a solvent. These solvents penetrate the tablets and dissolve some of the active ingredients. This creates a rough surface that cannot be polished to a high gloss Movie. In addition, coatings made from polymethacrylic acid resins, like shellac, are difficult to print on. After all, they have no adhesiveness and peel, if they are formed at all, easily off.

The coating can be applied using the usual Devices for coating tablets in a simple manner on both coated and also apply to uncoated tablets. So, if desired, a rotating drum can be used Coating can be used, the tablets being introduced first, and a solution of the coating resin is brought into contact with it. Any of inexpensive ones can be used to dissolve the resin Petroleum solvents, coal tar solvents, mineral oils, chlorinated hydrocarbons, long chain Alcohols and long chain ketones can be used. The resin concentration can range from 5 to 30 percent by weight of the solvent. The drum is covered for a short time to allow the Allow contact between the resin and the tablets before the solvent evaporates. on A stream of hot air can be applied to the tablets moving in the rolling drum. To The cover is removed for some time to allow the solvent to evaporate. At this time a stream of moderately warm air can be passed over the tablets to accelerate evaporation. After such drying, the tablets are in a state where they are printed, can be polished or packaged. The tablets obtained in this way are resistant to moisture, easy to print and polish and not sticky.

According to a preferred embodiment of the invention, a polymer essentially consists of. /? - Pinenen with a melting point in the range of 85 to 125 ° C existing resin for the preparation of the Lamination cover. Chlorinated hydrocarbons, for example, are used as solvents for the resin, such as chloroalkanes and preferably 1,1,1-trichloroethane into consideration. The resin solution is made by dissolving about 5 to 25 ° / »resin in the desired Solvent produced. If the penetrability of the resin into the tablet core is reduced then the viscosity of the resin solution can be adjusted accordingly with the aid of a thickener. The thickeners that can be used include, for example, cellulose-like substances such as cellulose esters, and a preferred thickening agent is ethyl cellulose. The thickener can be used in amounts up to be added to about 100% and preferably about 20 ° / d of the resin weight in the resin solution. But you can also add the resin solution to a solution of the ethyl cellulose.

It should also be noted that the thickener is advantageously self-film-forming Has properties which increase the moisture resistance of the coated tablet. Further, a minor amount of a dye can be added to the resinous coating if one wishes to obtain a colored tablet. Any compatible non-toxic dye is suitable for example dyes such as quinoline yellow. The dye can be in suspension or in solution in the Resin coating can be applied.

The coating material is then applied to the tablets. Standard working methods can be used are, for example, the above-described coating process in a drum. If a strong If gloss is to be achieved, then the tablets can after the application of the laminating coating subjected to a rolling motion for further time either alone or in the presence of powdered talc the desired shine is produced by the abrasive effect.

The following examples illustrate the invention without restricting it.

example 1

5 kg of sugar-coated tablets no. 3 produced by conventional methods are placed in a coating drum, which is then rotated. To the rolling tablets are then about 20 ml of a lO ° / o solution of a resin from Pinenpolymeren having a melting point of about 85 ^C C in 1,1,1-trichloroethane was added. The opening of the drum is immediately covered for 1 minute. The cover is removed and the coated tablets are allowed to roll until they are no longer sticky and the risk of them sticking together or sticking together is over. At this time, cold air is supplied. When the tablets are no longer sticky, they are removed and placed on shallow open containers in an oven with circulating warm air at about 40 ° C until all solvent is removed. The tablets are then polished by placing them in a waxed coating drum, the wax lining of which consists of 1 part by weight of carnauba wax and 3 parts by weight of beeswax, and letting them roll until they have acquired the desired gloss. The careful application of warm air to the rolling tablets promotes wax absorption and accelerates polishing.

The tablets can then be printed with the aid of a device designed for this purpose and then polished again as described above. The imprint can be used in front of the Polishing a second resin coating can also be applied.

Example 2

The same solutions are used as in Example 1, with the exception that the resin solution 20 «/ aig is.

3 kg of tablets No. 3 are carefully dusted off and placed in a 16-inch coating drum, which is then set in motion. So much resin solution is added that the tablets are uniform be coated. The drum is immediately covered until the solution is evenly distributed. After removing the cover, it becomes cold air

and the tablets are allowed to continue rolling until they are no longer sticky. Then will Take them out of the drum and place them evenly on flat, open containers with good ventilation exposed until the last traces of solvent have been removed.

Example 3

55 ml of a ^{solution containing 2 1} % ethyl cellulose and 0.05% quinoline yellow in 1,1,1-trichloroethane are prepared. 55 ml of a 15% solution of a /? - pinene resin (temperature = 85 ° C) in the same solvent are mixed with the ethyl cellulose solution while warming and then cooled to room temperature. The mixture is applied to tablets at room temperature in the following manner:

3 kg of # 2 sodium chloride tablets are placed in a 16 inch drum. There will be so much resin-ethyl cellulose solution added that the tablets are completely covered (110 ml). Once the tablets perform a free rolling motion, air is supplied until they are completely dry and none Have more solvent odor. Samples are taken and examined for disintegration (Average disintegration time in distilled water at 37 ° C about 3 minutes). Then a second coat is applied applied (about 60 ml) and repeated drying. After being pulled over twice, the mean disintegration time about 4 minutes.

The tablets have a smooth, uniform coating and a glossy appearance and are satisfactory the claims made on tablets coated with a film.

Example 4

5 kg of common vitamin mineral tablets are coated with sugar in the conventional way. To slow drying of the finished syrup coating to avoid crystallization as much as possible of the sugar are 50 ml of a 10% solution of the resinous polymer of / S-pinene (F. = 85 ° C) added to the rolling tablets. The tablets are dried with the help of cold air, until the last traces of solvent odor are removed. The tablets are polished in the way of making them roll in a rotating wax-lined drum; the drum is with a mixture (3: 1) of beeswax and carnauba wax lined. The tablets are then printed using a Hartnelt pressure device printed with the requested information. The film easily picks up the ink.

The printed tablets are corresponding tablets made with a pharmaceutical grade of shellac glazed and then printed, consider. This superiority manifests itself in a greater one Clarity of the print and the absence of imperfections in the lines and areas of the print.

Claims (2)

PATENT CLAIMS: 1. A process for producing a coating film on tablets, characterized in that the tablets are coated with a solution of a terpene polymer resin which melts between 70 and 135 ° C. 2. The method according to claim 1, characterized in that one is a resin of polymers von /? - pinenes with a melting point in the range of 85 to 125 ° C are used. 35 Publications considered:
Hager's Handbuch der Pharmazeutischen Praxis, 2nd supplementary volume, Berlin, 1958, pp. 1764 to 1767. © 109 757/544 12.61