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CN-121987581-A - Formula of low-viscosity enteric coating liquid and pill coating process

CN121987581ACN 121987581 ACN121987581 ACN 121987581ACN-121987581-A

Abstract

The invention relates to the technical field of coating material preparation, and discloses a formula of low-viscosity enteric coating liquid and a pill coating process, which comprise, by mass, 20-40 parts of a composite coating polymer, 60-80 parts of a dispersion medium, 2-6 parts of a plasticizer and 5-15 parts of a processing aid. The scheme constructs an ultra-stable low-solid-content coating system by introducing specific modified nanocellulose as a processing aid and generating electrostatic cooperation with negatively charged acrylic resin latex. The processing aid is used to build a stable network and redisperse the solid particles, thereby achieving a highly efficient, uniform enteric coating at low viscosities.

Inventors

  • ZHU JIANHUA
  • WU MIN
  • WU CHUNBIN

Assignees

  • 湖南健朗药业有限责任公司

Dates

Publication Date
20260508
Application Date
20260228

Claims (10)

  1. 1. The formula of the low-viscosity enteric coating liquid is characterized by comprising the following raw materials in parts by mass: 20-40 parts of composite coating polymer, 60-80 parts of dispersing medium, 2-6 parts of plasticizer and 5-15 parts of processing aid; The processing aid is prepared by carrying out high-pressure homogenization and oxidation modification treatment on cellulose nanofibers to obtain modified nanofibers, and then mixing the modified nanofibers with a surfactant to obtain the processing aid.
  2. 2. The formulation of a low viscosity enteric coating formulation according to claim 1, wherein the processing aid is prepared by the steps of: Dispersing cellulose nano fiber with deionized water, homogenizing the system under high pressure, circularly treating, setting the temperature of the system to 4-10 ℃, continuously stirring in the process, adding TEMPO reagent and sodium bromide, continuously stirring until the TEMPO reagent and sodium bromide are dissolved, dropwise adding sodium hypochlorite solution, regulating the pH value of the system to 10.0-10.5, adding ethanol after the pH value is unchanged, regulating the pH value of the system to be neutral, purifying the system to obtain modified nano fiber, adding surfactant into the modified nano fiber under the stirring condition, shearing for 10-20 minutes, and carrying out ultrasonic treatment for 5-10 minutes to obtain the processing aid.
  3. 3. The formulation of claim 2, wherein the high pressure homogenization is performed at a pressure of 1000-1500Bar and the number of cycles is 5-10.
  4. 4. The formulation of a low viscosity enteric coating according to claim 2, wherein the dosage ratio of cellulose nanofibers, TEMPO reagent, sodium bromide is 1g:0.1-0.2mmol:1-2mmol.
  5. 5. The formulation of claim 1, wherein the surfactant is at least one of polysorbate 80, poloxamer 188, and sodium lauryl sulfate.
  6. 6. The formulation of claim 1, wherein the composite coating polymer is prepared by mixing Eudragit ® L30D-55 with Eudragit NE 30D in a mass ratio of 1:1.
  7. 7. The formulation of claim 1, wherein the plasticizer is at least one of triethyl citrate, tributyl citrate, and polyethylene glycol 400.
  8. 8. The formulation of claim 1, wherein the formulation of the low viscosity enteric coating solution further comprises an anti-sticking opacifier, wherein the anti-sticking opacifier is at least one of talc, titanium dioxide, colloidal silica, and is used in synchronization with the plasticizer.
  9. 9. A process for coating a pellet of a low viscosity enteric coating liquid according to any of claims 1 to 8, comprising the steps of: S1, mixing a formula amount of composite coating polymer and a formula amount of dispersion medium at a speed of 300-500rpm for 20-30 minutes, keeping the temperature below 30 ℃ in the process, then increasing the rotating speed to 600-1000rpm, adding a processing aid, stirring for 10-15 minutes, adding a plasticizer, setting the rotating speed to 8000-12000 rpm, continuously stirring for 10-15 minutes, adding the rest dispersion medium, curing for 20-30 minutes, and stirring for 3-5 minutes again at 300-500rpm before use to obtain a low-viscosity enteric coating liquid; s2, putting the pills into coating equipment, preheating to a material bed temperature of 28-32 ℃, then coating by using the low-viscosity enteric coating liquid obtained in the step S1, continuously tumbling and fluidizing for 5-10 minutes after the coating is finished, and then discharging and curing in a drying tray for 12-24 hours in a dark place, wherein the curing temperature is 30-40 ℃.
  10. 10. The process for coating a pellet of a low viscosity enteric coating liquid according to claim 9, wherein the coating is performed at a coating spray rate of 2-6g/min/kg pellet core, the spray rate is raised to 5-15g/min/kg pellet core after 10-15 minutes, the atomization pressure is 0.6-1.8Bar, the air inlet temperature is 45-60 ℃, and the air volume is controlled to maintain the material bed temperature at 30-35 ℃.

Description

Formula of low-viscosity enteric coating liquid and pill coating process Technical Field The invention relates to the technical field of coating material preparation, in particular to a formula of low-viscosity enteric coating liquid and a pill coating process. Background In the field of pharmaceutical preparations, in particular to enteric delivery of pill, pellet or tablet coatings, low-viscosity enteric coating solutions are favored for their good atomization performance and lower spray burden, however, such coating solutions have long faced several prominent technical bottlenecks in practical formulation and production applications: Firstly, due to the low viscosity and solid content, solid particles in the coating liquid such as polymer colloidal particles, anti-adhesion agents, opacifiers and the like are difficult to stably suspend for a long time, sedimentation, delamination or phase separation are very easy to occur, so that the coating liquid is poor in consumption stability and is often required to be prepared and used at present, secondly, on the selection of the coating polymer, in order to obtain the low viscosity characteristic, a single type of enteric polymer or a simple dispersion thereof is often used, but the adjustability of the mechanical property, flexibility or release curve of the coating film is possibly sacrificed, and if the polymer with different characteristics is tried to be compounded to optimize the film performance, the mixed system is unstable and is easy to generate phase separation due to poor compatibility among latex particles or lack of effective co-stabilization mechanism, so that the film forming quality is deteriorated. Finally, at the coating process level, the conventional material mixing sequence may not be designed for constructing a stable colloidal network, for example, after adding key stable components or solid powder, an effective isolation and support structure may not be formed in advance in a liquid phase, so that the stability potential of the auxiliary agent cannot be utilized to the maximum extent, and the defects together lead to common pain points in industries such as narrow process window, difficult control of film forming quality, poor performance reproducibility and the like of the low-viscosity enteric coating liquid, so that the wide application of the low-viscosity enteric coating liquid in the efficient and stable preparation production is restricted. Based on the formula, the application provides a formula of low-viscosity enteric coating liquid and a pill coating process. Disclosure of Invention Technical problem to be solved Aiming at the defects of the prior art, the invention provides a formula of low-viscosity enteric coating liquid and a pill coating process, which solve the problems of poor stability, narrow process window, difficult control of film forming quality and the like of the low-viscosity enteric coating liquid for a long time. Technical proposal In order to achieve the above purpose, the present invention provides the following technical solutions: The formula of the low-viscosity enteric coating liquid comprises the following raw materials in parts by mass: 20-40 parts of composite coating polymer, 60-80 parts of dispersing medium, 2-6 parts of plasticizer and 5-15 parts of processing aid; The processing aid is prepared by carrying out high-pressure homogenization and oxidation modification treatment on cellulose nanofibers to obtain modified nanofibers, and then mixing the modified nanofibers with a surfactant to obtain the processing aid. Further, the processing aid is specifically prepared by the following steps: Dispersing cellulose nano fiber with deionized water, homogenizing the system under high pressure, circularly treating, setting the temperature of the system to 4-10 ℃, continuously stirring in the process, adding TEMPO reagent and sodium bromide, continuously stirring until the TEMPO reagent and sodium bromide are dissolved, dropwise adding sodium hypochlorite solution, regulating the pH value of the system to 10.0-10.5, adding ethanol after the pH value is unchanged, regulating the pH value of the system to be neutral, purifying the system to obtain modified nano fiber, adding surfactant into the modified nano fiber under the stirring condition, shearing for 10-20 minutes, and carrying out ultrasonic treatment for 5-10 minutes to obtain the processing aid. Further, the processing aid is specifically prepared by the following steps: Dispersing cellulose nanofibers with deionized water until the solid content is about 0.5% -1.0%, then inputting the system into a high-pressure homogenizer for cyclic treatment, then inputting the system into a temperature-controlled reactor, setting the system temperature to be 4-10 ℃, continuously stirring in the process, adding TEMPO reagent and sodium bromide, continuously stirring until the mixture is dissolved, dropwise adding sodium hypochlorite solution, regulating the p