PigmentsTwo types of pigments i.e.,

Pigments
Two types of pigments i.e., opacifying agents (Titanium Dioxide (TiO2)) and coloring agents are used in the coating formulation of Methacrylic Acid Copolymer Dispersion NF. Pigments significantly impact the mechanical, adhesive, and drug-release properties of the resulting film. Water vapor permeability of the polymeric film increases with increasing pigment concentration. This is because the polymer cannot hold the pigments together, resulting in the creation of a void, increasing permeability and decreasing the mechanical strength of the film (36, 37). Therefore, a greater coating thickness is required to ensure delayed release. There is a significant increase in the Tg of the Methacrylic Acid Copolymer film with increased concentration of TiO2 when applied to hydrophilic tablets (10). The Tg of the Methacrylic Acid Copolymer Dispersion NF film coated on hydrophilic and hydrophobic tablets with 0% v/v TiO2 with
respect to the dry polymer is 36.5°C and 49.3°C whereas with 20% v/v with respect to the dry polymer is 49.3°C and 51.9°C respectively (10). Therefore, the tensile strength of the film
decreases with increasing TiO2 concentration as evidenced from the EaB. The EaB of the polymeric film produced using TiO2 at 2% w/w concentration with respect to the polymer is about 40%, decreasing to about 10% at 6% w/w concentration of TiO2 (38). The reason for a decrease in the EaB is attributed to the CPVC value of the polymeric film produced using TiO2, which is 13.5 - 15.0% v/v (34). Film adhesion on the tablet surface increases, with an increase in the TiO2 concentration until optimal concentration has been reached, after which film adhesion decreases. This is because exceeding the optimal concentration of TiO2 increases the internal stress of the polymeric film causing weaker film adhesion. An increase in the internal stress and weaker film adhesion causes film cracking. The crack resistance of the polymeric film containing TiO2 is greater compared with talc. This is attributed to the difference in particle shape of the talc (platelike) and TiO2 (round irregular) (13).
The commonly used lakes in the Methacrylic Acid Copolymer Dispersion NF formulations are yellow ferric oxide, red ferric oxide, and aluminum lakes i.e., Blue No. 1 and Yellow No. 6. A significant portion of the polymer is associated with the lakes, leaving less polymer available for film formation (29). The CPVC of the polymeric film containing the aluminum lakes is high compared to the iron oxide pigmented films. The rationale is that aluminum lakes are highly aggregated pigments with a large surface area which requires a lot of energy for dispersion. The aggregation of the aluminum lakes limits the external surface available to the polymer, leading to the relatively high CPVC value. The particles of both the insoluble colors i.e., yellow ferric oxide and red ferric oxide aggregate. A more open structure is formed by the yellow ferric oxide and is associated with fewer polymers compared to red ferric oxide (29). The CPVC
values of the polymeric films produced using aluminum lake Yellow No. 6, yellow ferric oxide and red ferric oxide are 12.0–13.5 % v/v, 10.0 – 12.0 % v/v and 8.5–10.0% v/v respectively (34). The higher the CPVC values, the lower the mechanical properties of the polymeric film.
A large pigment concentration may cause coagulation of the anionic polymers e.g., Methacrylic Acid Copolymer Dispersion NF. This is because pH values below 5 influences the zeta potential of the spray suspension resulting in coagulation. To prevent coagulation of the polymer due to the impact of insoluble excipients and high plasticizer concentration the addition of 1 N NaOH or low viscous hydrocolloids such as Na-CMC is recommended to stabilize the dispersion before
mixing it with the pigment suspension (16).
Optimizing the total insoluble excipients in the Methacrylic Acid Copolymer Dispersion NF tablet core formulation is one of the most critical considerations, especially when it is applied to hygroscopic tablet cores, to ensure the mechanical integrity of the film. Ideally, the insoluble excipients should range from 35 to 50% w/w of dry polymer, when applied to hygroscopic tablet cores. At this concentration the polymer completely covers the insoluble excipients as fewer polymers are associated with the insoluble excipients.

Результаты (русский) 1:

PigmentsTwo types of pigments i.e., opacifying agents (Titanium Dioxide (TiO2)) and coloring agents are used in the coating formulation of Methacrylic Acid Copolymer Dispersion NF. Pigments significantly impact the mechanical, adhesive, and drug-release properties of the resulting film. Water vapor permeability of the polymeric film increases with increasing pigment concentration. This is because the polymer cannot hold the pigments together, resulting in the creation of a void, increasing permeability and decreasing the mechanical strength of the film (36, 37). Therefore, a greater coating thickness is required to ensure delayed release. There is a significant increase in the Tg of the Methacrylic Acid Copolymer film with increased concentration of TiO2 when applied to hydrophilic tablets (10). The Tg of the Methacrylic Acid Copolymer Dispersion NF film coated on hydrophilic and hydrophobic tablets with 0% v/v TiO2 withrespect to the dry polymer is 36.5°C and 49.3°C whereas with 20% v/v with respect to the dry polymer is 49.3°C and 51.9°C respectively (10). Therefore, the tensile strength of the filmуменьшается с увеличением концентрации TiO2 свидетельством от ЭПБ. ЭПБ полимерной пленки, вырабатываемый TiO2 в концентрации 2% w/w в отношении полимер составляет около 40%, сократился до примерно 10% в 6% w/w концентрация TiO2 (38). Причиной снижения ЭПБ приписывается значение CPVC полимерные пленки изготавливаются с использованием TiO2, который является 13,5-15,0% v/v (34). Адгезия пленки на поверхности планшета возрастает с увеличением концентрации TiO2, пока не будет достигнута оптимальная концентрация, после чего уменьшается адгезия пленки. Это потому, что превышает оптимальную концентрацию TiO2 увеличивает внутренний стресс полимерной пленки, вызывая слабее адгезия пленки. Увеличение внутренних напряжений и слабее адгезия пленки вызывает растрескивание фильм. Трещиностойкости полимерные пленки, содержащие TiO2 больше по сравнению с тальком. Это связано с разницей в форма частиц и тальк (пластинчатые) TiO2 (раунд нерегулярных) (13).The commonly used lakes in the Methacrylic Acid Copolymer Dispersion NF formulations are yellow ferric oxide, red ferric oxide, and aluminum lakes i.e., Blue No. 1 and Yellow No. 6. A significant portion of the polymer is associated with the lakes, leaving less polymer available for film formation (29). The CPVC of the polymeric film containing the aluminum lakes is high compared to the iron oxide pigmented films. The rationale is that aluminum lakes are highly aggregated pigments with a large surface area which requires a lot of energy for dispersion. The aggregation of the aluminum lakes limits the external surface available to the polymer, leading to the relatively high CPVC value. The particles of both the insoluble colors i.e., yellow ferric oxide and red ferric oxide aggregate. A more open structure is formed by the yellow ferric oxide and is associated with fewer polymers compared to red ferric oxide (29). The CPVCvalues of the polymeric films produced using aluminum lake Yellow No. 6, yellow ferric oxide and red ferric oxide are 12.0–13.5 % v/v, 10.0 – 12.0 % v/v and 8.5–10.0% v/v respectively (34). The higher the CPVC values, the lower the mechanical properties of the polymeric film.A large pigment concentration may cause coagulation of the anionic polymers e.g., Methacrylic Acid Copolymer Dispersion NF. This is because pH values below 5 influences the zeta potential of the spray suspension resulting in coagulation. To prevent coagulation of the polymer due to the impact of insoluble excipients and high plasticizer concentration the addition of 1 N NaOH or low viscous hydrocolloids such as Na-CMC is recommended to stabilize the dispersion beforemixing it with the pigment suspension (16). Optimizing the total insoluble excipients in the Methacrylic Acid Copolymer Dispersion NF tablet core formulation is one of the most critical considerations, especially when it is applied to hygroscopic tablet cores, to ensure the mechanical integrity of the film. Ideally, the insoluble excipients should range from 35 to 50% w/w of dry polymer, when applied to hygroscopic tablet cores. At this concentration the polymer completely covers the insoluble excipients as fewer polymers are associated with the insoluble excipients.