Colorant composition for film coating suitable for UV laser printing, and UV laser printing method using said composition

Abstract

One aspect of the present invention provides a film coating composition that can replace titanium oxide, which is suspected to be carcinogenic, and is particularly suitable for laser printing after film coating. The present invention also provides a film coating composition that has excellent white coloring effect and reduced scuffing phenomenon. Another aspect of the present invention provides a method for laser printing on tablets or capsules using the composition according to the present invention.

Description

[Technical field]

[0001] This application claims priority to Korean Patent Application No. 10-2022-0026538 filed on March 2, 2022, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings.

[0002] The present invention relates to a colorant that can replace titanium oxide, which is a colorant suspected of being carcinogenic, and a film coating composition containing such a colorant. In particular, the present invention relates to a film coating composition suitable for laser printing. The present invention also relates to a method of coating a plain tablet or capsule with such a film coating composition and performing UV laser printing thereon. [Background technology]

[0003] Titanium dioxide (TiO2) is commonly used as a white colorant in polymeric film coatings for tablets or capsules.

[0004] In addition, it is common to laser-print specific marks on the surface of tablets or capsules for identification purposes, and titanium dioxide is recognized as an essential ingredient that enables such laser printing.

[0005] However, in recent years, the potential carcinogenicity of titanium dioxide (TiO2) has become an issue, as the European Union's Executive Committee has classified titanium dioxide (TiO2) as a carcinogen. Therefore, the use of titanium dioxide is being discontinued, and alternative colorants that can be white or hide other colors of bare tablets are required. Meanwhile, commonly used UV laser printers print by removing oxygen from titanium dioxide to induce the coloring of titanium. Therefore, the current situation is that printing with a UV laser printer is impossible without the use of titanium dioxide. Therefore, there is an urgent need for a film coating composition that can be laser printed without titanium dioxide. That is, a method is required that can coat bare tablets or capsules without the use of titanium dioxide and can be laser printed on the coated tablets. Summary of the Invention [Problem to be solved by the invention]

[0006] Therefore, the problem to be solved by the present invention is to provide a new colorant capable of replacing titanium oxide, which is a conventional colorant, and a film coating composition containing the new colorant.

[0007] In particular, the present invention seeks to provide a film coating composition that is laser printable.

[0008] Further, the present invention is intended to provide a method for film-coating a plain tablet or capsule with the film-coating composition and then performing laser printing thereon. [Means for solving the problem]

[0009] In order to solve the above problems, one aspect of the present invention provides a polymer composition for film coating of tablets or capsules, comprising (a) zinc oxide and (b) at least one selected from the group consisting of talc, calcium carbonate, and magnesium oxide. Preferably, the polymer composition for film coating according to the present invention comprises (a) zinc oxide and (b) talc.

[0010] Preferably, in the present invention, the tablets or capsules are laser printed after film coating, and the film coating formed by the film coating composition according to the present invention is suitable for such laser printing.

[0011] In a preferred embodiment of the present invention, the content of (b) talc, calcium carbonate, magnesium oxide, or a mixture thereof in the composition is 5% by weight to 40% by weight (preferably, 5% by weight to 35% by weight) based on the total weight of the remaining dry material excluding the coating solvent, and the content of (a) zinc oxide is 1% by weight to 30% by weight (preferably, 1% by weight to 20% by weight, more preferably 1% by weight to 10% by weight) based on the total weight of the remaining dry material excluding the coating solvent.

[0012] In the present invention, unless otherwise stated, the content is based on the total weight of the remaining dry material excluding the coating solvent.

[0013] In a preferred embodiment of the present invention, the film coating composition according to the present invention further comprises a plasticizer, which may be triacetin, polyethylene glycol, lecithin or a mixture thereof. For the purpose of the present invention, which is laser printing, the film coating composition according to the present invention preferably comprises polyethylene glycol as a plasticizer. As such polyethylene glycol, polyethylene glycol 400, polyethylene glycol 3350, polyethylene glycol 4000, polyethylene glycol 6000, etc. may be used, and for the purpose of the present invention, the polyethylene glycol system does not affect printing.

[0014] Such plasticizers may be used at 3% to 25% by weight, preferably 10% to 20% by weight, based on the total weight of the film coating composition.

[0015] In the film coating composition for forming a film layer suitable for laser printing according to the present invention, the polymer for forming the film layer may be polyvinyl alcohol, hypromellose, polyvinylpyrrolidone, methacrylic acid copolymer, hydroxypropyl cellulose, or a mixture thereof. Such a film coating polymer may be used in an amount of 30% to 75% by weight, preferably 40% to 70% by weight, more preferably 40% to 60% by weight, based on the total weight of the film coating composition.

[0016] Optionally, the film coating composition of the present invention may further contain a colored pigment in addition to the white colorant. Such a colorant may be an aluminum lake pigment, an iron oxide pigment, a natural pigment such as gardenia, etc., which may be used alone or in combination, and may be contained in an amount of 0.01 to 8% by weight based on the total weight of the film coating composition within a range that does not interfere with the above content ratio.

[0017] The film coating composition of the present invention may be provided in the form of a solid powder, or may be provided in the form of a coating liquid by mixing with a suitable solvent. When the composition of the present invention is provided as a coating liquid, the content of each component is evaluated based on the total weight of the remaining dry material excluding the coating solvent.

[0018] The coating solvent may preferably be selected from the group consisting of water, ethanol and mixtures thereof.

[0019] The present invention also provides a UV laser printing method for tablets or capsules, comprising the steps of (S1) film-coating a plain tablet or capsule with the film-coating composition according to the present invention described above, and (S2) printing the film-coated tablet or capsule with a laser, preferably a UV laser.

[0020] The laser device and laser light for printing (marking) the coated film with a UV laser are not particularly limited, and the laser medium may be irradiated with the laser in any one of a solid state, a liquid state, and a gas state. As the solid-state laser, a YLF laser, a YAG laser, a YVO4 laser, a fiber laser, etc. may be used, but are not limited thereto. Effect of the Invention

[0021] One aspect of the present invention provides a film coating composition capable of forming a film layer suitable for laser printing without using titanium oxide, which is suspected to be carcinogenic. Tablets or capsules coated with the film coating composition of the present invention have excellent white coloring effect and reduced scuffing phenomenon, making them suitable for laser printing. [Brief description of the drawings]

[0022] [Figure 1] 1 is a photographic result taken after laser printing on a white tablet film-coated with an example composition according to the present invention. [Diagram 2] 1 is a photographic result taken after laser printing on a tablet film-coated with a comparative composition. [Diagram 3] 1 is a photographic result taken after laser printing on a colored tablet film-coated with an example composition according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, for the purpose of facilitating the understanding of the present invention, examples and the like will be given for a detailed explanation. However, the examples according to the present invention can be deformed into various other forms, and it should not be construed that the scope of the present invention is limited to the following examples. The examples of the present invention are provided to more fully explain the present invention to those with average knowledge in the field to which the present invention belongs.

[0024] <Manufacture of White Film Coating Tablets for UV Laser Printing> A variety of film coating tablets for testing UV laser printing were manufactured. White film coating was performed on the same naked tablets according to the formulation in Table 1 below. Specifically, 60 parts by weight of the coating base in Table 1 below and about 270 parts by weight of tablet water were mixed to produce a coating solution. Then, at conditions such as an inlet temperature of 58 °C, a rotation speed of the coating fan of 30 rpm, a pump speed of 3.5 rpm, and an air flow of 140 m 3 / hr, film coating was performed until the weight of the naked tablets (716 mg) increased by 8% by weight. The total coating time was about 56 minutes. The coating equipment used was XENA-IV BTC was used.

[0025]

Table 1

[0026] Next, a printing test was performed on the film coating of each tablet using a UV laser printing device (Enclony PLPI, manufactured by Enclony). The printability was evaluated, and the results are shown in Table 2 below. Also, a photo of the film tablets that could be successfully printed is shown in Figure 1, and the photographing results of the examples where printing was substantially impossible are shown in Figure 2.

[0027]

Table 2

[0028] As shown in Table 2, the conventional film coating containing titanium oxide was suitable for laser printing. However, in the case of a film coating containing only talc, calcium carbonate or magnesium oxide, the printed marks could not be visually identified to such an extent that UV laser printing was substantially impossible. On the other hand, when a small amount of zinc oxide was contained, laser printing was possible.

[0029] <Manufacture of Colored Film Coating Tablets for UV Laser Printing> The effect of the composition of the present invention in a colored coating rather than a white coating was evaluated. Film coating tablets were manufactured in the same manner as in Example 1 according to the formulation shown in Table 3 below.

[0030]

Table 3

[0031] Next, laser printing was performed in the same manner as in the above-described experiment, and the results are shown in Figure 3. As shown in Figure 3, the film coating composition according to the present invention was suitable for laser printing, and the film coating process and the film coating itself generated thereafter were also good.

Claims

1. A polymer composition for film coating of tablets or capsules, comprising: (a) zinc oxide; and (b) one or more selected from the group consisting of talc, calcium carbonate, and magnesium oxide.

2. 2. The film coating composition of claim 1, wherein the composition comprises: (a) zinc oxide; and (b) talc.

3. 3. The film coating composition according to claim 1 or 2, wherein after said film coating the tablets or capsules are laser printed.

4. 3. The film coating composition according to claim 1 or 2, wherein the content of (b) talc, calcium carbonate, magnesium oxide, or a mixture thereof in the composition is 5 wt% to 40 wt% based on the total weight of the remaining dry material excluding the coating solvent, and the content of (a) zinc oxide is 1 wt% to 30 wt% based on the total weight of the remaining dry material excluding the coating solvent.

5. 2. The film coating composition of claim 1, wherein the polymer is polyvinyl alcohol, hypromellose, polyvinylpyrrolidone, methacrylic acid copolymer, hydroxypropyl cellulose, or a mixture thereof.

6. (S1) a step of film-coating a tablet or capsule with the film-coating composition according to any one of claims 1 to 5; (S2) a step of laser printing on the tablet or capsule coated in step S1.

7. 7. A method for laser printing tablets or capsules according to claim 6, wherein said laser is a UV laser.

Images