Edible ink composition containing magnesium oxide

Abstract

An edible ink composition is prepared that includes magnesium oxide as a whitening agent, a binder, a solvent, and is free of titanium oxide. The edible ink composition of the present invention uses magnesium oxide instead of titanium oxide as a whitening agent. Magnesium oxide has been safely used as a medicament, deemed to have no health problems. Therefore, it can be used for printing on the surfaces of solid food, solid pharmaceutical preparations, in particular capsules, tablets and capsule tablets.

Description

(19) State Intellectual Property Office (12) Invention Patent Application (10) Application Publication Number (43) Application Publication Date (21) Application Number 202480057223.3 (22) Application Date 2024.09.05 (30) Priority Data 23196762.1 2023.09.12 EP PCT / JP2023 / 032692 2023.09.07 JP PCT / JP2024 / 015673 2024.04.22 JP PCT / JP2024 / 024688 2024.07.09 JP (85) PCT International Application Entering National Phase Date 2026.03.06 (86) PCT International Application Application Data PCT / JP2024 / 031806 2024.09.05 (87) Publication data of PCT international application WO2025 / 053196 JA 2025.03.13 (71) Applicant Belgian Capsule Company Address Borneum, Belgium (72) Inventors Takahisa Takubo Kaori Sato (74) Patent Agency Shanghai Shengkang Law Firm 31263 Patent Attorneys Li Xianzong Zhang Jing (51) Int.Cl. C09D 11 / 322 (2006.01) A23L 5 / 00 (2006.01) (54) Invention Title Edible Ink Composition Containing Magnesium Oxide (57) Abstract An edible ink composition containing magnesium oxide as a whitening agent, binder, and solvent has been prepared and is free of titanium oxide. The edible ink composition of the present invention uses magnesium oxide instead of titanium oxide as a whitening agent. Magnesium oxide has been safely used as a pharmaceutical agent and is considered to have no health problems. Therefore, it can be used for printing on the surface of solid food, solid pharmaceutical preparations, especially capsules, tablets and sachets. Claims (2 pages), Description (14 pages), CN 121844013 A, 2026.04.10, CN 1 21 84 40 13 A 1. An edible ink composition comprising magnesium oxide, a binder, and a solvent, wherein the magnesium oxide is produced at a calcination temperature of at least 700°C, and the edible ink composition is free of titanium oxide. 2. The edible ink composition of claim 1, wherein the magnesium oxide is produced at a calcination temperature of at least 800°C. 3. The edible ink composition of claim 1 or 2, wherein the D90 value of the magnesium oxide is 20 μm or less. 4. The edible ink composition of any one of claims 1 to 3, wherein the particle size distribution D90 value of the magnesium oxide is 1 to 15 μm. 5. The edible ink composition of any one of claims 1 to 4, wherein the particle size distribution D10 value of the magnesium oxide is 0.1 μm or greater.6. The edible ink composition according to any one of claims 1 to 5, wherein after drying, the amount of magnesium oxide in the ink is 99 wt% or less, preferably 60 to 99 wt%, said wt% based on the weight of the ink after drying. 7. The edible ink composition according to any one of claims 1 to 6, wherein the solid content of the edible ink composition is 65 wt% or less, preferably 20 to 65 wt%, by weight of the edible ink composition. 8. The edible ink composition according to any one of claims 1 to 7, wherein the solvent substantially evaporates or evaporates and does not remain in the ink after drying. 9. The edible ink composition according to any one of claims 1 to 8, wherein the solvent is an alcohol or a mixture of alcohol and water, said alcohol preferably being ethanol, propanol, or butanol, more preferably ethanol or butanol; even more preferably, said alcohol is ethanol. 10. The edible ink composition according to any one of claims 1 to 9, wherein the binder is preferably an edible film-forming and non-thermosetting polymer or shellac, and the binder is soluble in alcohol, and when the binder is a non-thermosetting polymer, the binder is hydroxypropyl cellulose, polyvinylpyrrolidone, or a mixture thereof. 11. The edible ink composition according to any one of claims 1 to 10, comprising a moisture-resistant coating agent. 12. The edible ink composition according to claim 11, wherein the moisture-resistant coating agent is a higher fatty acid ester, C16 or higher alcohol, C12 or higher fatty acid, glyceride, or a mixture thereof that is soluble or miscible in alcohol but insoluble in water, or a surfactant with an HLB value of 6 or less. 13. The edible ink composition according to claim 11 or 12, wherein the moisture-proof coating agent is stearic acid, beeswax such as white beeswax, resin such as rosin, wood wax, cetyl alcohol, lanolin, lanolin alcohol, cetyl alcohol, stearyl alcohol, cetyl alcohol monostearate polyethylene glycol mixed wax, cetyl alcohol polysorbate 60 mixed wax, cetyl stearyl alcohol, isopropyl myristate, isopropyl linoleate, isopropyl palmitate, vegetable oil such as oleic acid, olive oil, castor oil. 14. The edible ink composition according to any one of claims 11 to 13, wherein the amount of the moisture-proof coating agent is 0.1 to 20%, preferably 0.1 to 10%, based on the combined weight of the magnesium oxide and the binder. 15. The edible ink composition according to any one of claims 1 to 14, comprising another colorant having a color other than white.16. The edible ink composition according to any one of claims 1 to 15, comprising one or more additives commonly used in printing inks as described on page 1 / 2 of CN 121844013 A, such as drying speed regulators, plasticizers, wetting agents, tackifiers, ink gloss agents, thixotropic agents, and fragrances; possible additives include glycerol, triethyl citrate (TEC), triacetin, ethylene glycol, propylene glycol, resins, waxes, polyglycerol fatty acid esters, glycerol fatty acid esters, sucrose fatty acid esters, sorbitan fatty acid esters, lecithin, enzymatically degraded lecithin, polysorbate, silica (SiO2), starch, alcohol-insoluble cellulose, fragrances, and / or combinations thereof. 17. A printing substrate printed with the edible ink composition according to any one of claims 1 to 16; preferably, the printing substrate is a solid food or solid pharmaceutical preparation, the solid pharmaceutical preparation preferably being a hard capsule, soft capsule, tablet, or capsule capsule. 18. A method for preparing an edible ink composition, the method comprising the step of mixing components of the edible ink composition to provide an edible ink composition according to any one of claims 1 to 16, said components being magnesium oxide, a binder, a solvent, and any optional components such as additives. 19. A method for printing an edible ink composition on a printing substrate, using the edible ink composition according to any one of claims 1 to 16 and said printing substrate. Claims 2 / 2 Page 3 CN 121844013 A Edible Ink Composition Containing Magnesium Oxide Technical Field

[0001] The present invention relates to an edible ink composition. In particular, the present invention relates to an edible ink composition containing magnesium oxide as a white pigment, the edible ink composition being free of titanium oxide. The present invention relates to edible ink compositions suitable for printing on the surface of solid food or solid pharmaceutical preparations (such as sweets, candies, tablets, capsules, and granules). Furthermore, the present invention relates to solid food and solid pharmaceutical preparations (such as tablets, capsules, and granules) printed with an edible ink composition containing magnesium oxide. Background Art

[0002] Solid foods (such as sweets or candies) and solid pharmaceutical preparations (such as tablets, capsules, and pouches) are typically printed with symbols, characters, and / or patterns on their surfaces for product identification. In particular, printing on solid pharmaceutical preparations is widely used as a means of transmitting various information such as product names, codes, company names (such as their symbolic markings).

[0003] Traditionally, printing on solid pharmaceutical preparations and solid foods is typically done using edible printing inks, which contain pigments mixed or dispersed in a carrier, such as titanium dioxide, ferric oxide, and edible aluminum lakes, wherein shellac is dissolved in an alcohol-based organic solvent (Patent Document 1 and Patent Document 2).

[0004] Shellac is a thermosetting resin produced by Laccifer lacca and is harmless to humans. Due to its adhesion to surfaces, it is used as a binder for edible inks in many countries.

[0005] Water-insoluble white inorganic fine powders used to whiten edible ink compositions are known to be water-insoluble calcium salts, such as calcium carbonate and calcium phosphate, titanium dioxide, magnesium carbonate, and shell powder (i.e., ground calcium carbonate) (Patent Document 3). The main component of shell powder is calcium carbonate.

[0006] Among these white pigments, titanium dioxide has a high refractive index and high hiding power and tinting strength. Therefore, it is widely used not only as a white pigment but also in combination with other non-white colorants. However, in 2020, the European Union (EU) designated titanium dioxide as "Carcinogenic Category 2" and banned its use in the European food market from 2022. https: / / www.jetro.go.jp / biznews / 2022 / 08 / 817e100825b5eb14.html Furthermore, in the EU, it is said that the use of titanium dioxide in pharmaceuticals will be banned around 2025.

[0007] Therefore, there is an urgent need to develop an edible white ink composition that does not contain titanium dioxide for use in the food and pharmaceutical fields.

[0008] Patent document 4 describes an example of using other materials to replace titanium dioxide in the field of edible inks. The edible ink composition contains a yellow oil-based natural coloring material, characterized by 10-15% by weight of the above-mentioned oil-based natural coloring material, 15-40% by weight of edible oil or fat as a carrier, and 50-70% by weight of eggshell calcium. The main component of eggshell calcium is calcium carbonate.

[0009] However, there are no reports of white pigments with whiteness and hiding power comparable to titanium dioxide, suitable for edible inks.

[0010] There are instances where magnesium oxide is added as a light-shielding agent to a coating agent to impart light-shielding properties to the surface of a solid pharmaceutical preparation (Patent Documents 5 and 6). However, the coating agent is not an ink composition.

[0011] Furthermore, Patent Document 7 describes an edible ink containing 10 to 35 parts by weight of an edible colorant, 20 to 85 parts by weight of an edible binder, 0 to 1 part by weight of an edible adjuvant, and 0.5 to 5 parts by weight of an edible nanomaterial. Nanomaterials include nano-sized titanium dioxide, nano-sized magnesium oxide, nano-sized calcium carbonate, etc. However, since nanomaterials (also known as nanoparticles (particles with a diameter of 100 nm or smaller) can enter the human body through the respiratory tract, digestive tract, skin, and mucous membranes, they may pose a safety concern.

[0012] Prior art documents: Patent Document 1: JPS47-31706A; Patent Document 2: JP2020-29537A; Patent Document 3: JPS63-63363A; Patent Document 4: JPH8-308533A; Patent Document 5: JP2003-300872A; Patent Document 6: US2014 / 0251181A1; Patent Document 7: CN102942819A Summary of the Invention

[0013] (Problems to be Solved by the Invention) The first object of the present invention is to provide an edible ink composition suitable for printing on the surface of solid food or solid pharmaceutical preparations, which does not have the carcinogenic problems of titanium dioxide.

[0014] The second object of the present invention is to provide an edible ink composition with good adhesion and long-term stability to the surface of printing substrates.

[0015] The third object of the present invention is to provide an edible ink composition with good hiding power and coloring power.

[0016] (Solution to the Problem) The inventors of the present invention have conducted repeated research and found a novel edible colorant that is not titanium dioxide that can be applied to white inks, and have discovered that printing inks containing magnesium oxide can be used for printing with clear markings.

[0017] Magnesium oxide is a chemical substance commonly used in pharmaceuticals as an antacid and laxative, and also as a food additive. Therefore, it can be safely used as a white pigment in edible ink compositions.

[0018] Furthermore, edible ink compositions containing magnesium oxide meet the required stability and performance, and are therefore suitable for printing on solid pharmaceutical preparations and solid foods.

[0019] In addition to magnesium oxide, the edible ink compositions of the present invention also contain binders and solvents. Furthermore, the edible ink compositions can contain plasticizers, wetting agents, and other additives in a conventional manner, and in the presence of these additives, they can fully achieve their purpose as printing inks.

[0020] The present invention is made based on the above findings and includes the following aspects.

[0021] [1] An edible ink composition comprising magnesium oxide, a binder, and a solvent, wherein the magnesium oxide is prepared at a calcination temperature of at least 700°C, and the edible ink composition is free of titanium oxide.

[0022] [2] The edible ink composition according to [1], wherein the magnesium oxide is prepared at a calcination temperature of at least 800°C.

[0023] [3] The edible ink composition according to [1] or [2], wherein the D90 value of the magnesium oxide is 20 μm or less. [4] The edible ink composition according to any one of [1] to [3], wherein the particle size distribution D90 value of the magnesium oxide is 1 to 15 μm.

[0024] [5] The edible ink composition according to any one of [1] to [4], wherein the particle size distribution D10 value of magnesium oxide is 0.1 μm or greater. Specification 2 / 14 page 5 CN 121844013 A

[0025] [6] The edible ink composition according to any one of [1] to [5], wherein after the edible ink composition is dried, the amount of magnesium oxide in the ink is 99 wt% or less, preferably 60 to 99 wt%, wt% based on the weight of the ink after the edible ink composition is dried.

[0026] [7] The edible ink composition according to any one of [1] to [6], wherein the solid content of the edible ink composition is 65 wt% or less of the weight of the edible ink composition, preferably 20 to 65 wt%.

[0027] [8] The edible ink composition according to any one of [1] to [7], wherein the solvent is substantially volatile or evaporated and does not remain in the ink after the edible ink composition is dried.

[0028] [9] The edible ink composition according to any one of [1] to [8], wherein the solvent is an alcohol or a mixture of alcohol and water, preferably ethanol, propanol or butanol, more preferably ethanol or butanol; even more preferably, the alcohol is ethanol.

[0029]

[10] The edible ink composition according to any one of [1] to [9], wherein the binder is preferably an edible film-forming and non-thermosetting polymer or shellac, and when the binder is a non-thermosetting polymer, the binder is soluble in alcohol, more preferably, the binder is hydroxypropyl cellulose, polyvinylpyrrolidone or a mixture thereof.

[0030]

[11] The edible ink composition according to any one of [1] to

[10] , comprising a moisture-proof coating agent.

[0031]

[12] The edible ink composition according to

[11] , wherein the moisture-proof coating agent is a higher fatty acid ester, C16 or higher alcohol, C12 or higher fatty acid, glyceride or a mixture thereof, soluble in or miscible with alcohol but insoluble in water, or a surfactant with an HLB value of 6 or lower.

[0032]

[13] The edible ink composition according to

[11] or

[12] , wherein the moisture-proof coating agent is stearic acid, beeswax such as white beeswax, resin such as rosin, wood wax, cetyl alcohol, lanolin, lanolin alcohol, cetyl alcohol, stearyl alcohol, cetyl alcohol monostearate polyethylene glycol mixed wax, cetyl alcohol polysorbate 60 mixed wax, cetyl stearyl alcohol, isopropyl myristate, isopropyl linoleate, isopropyl palmitate, vegetable oil such as oleic acid, olive oil, castor oil, etc.

[0033]

[14] The edible ink composition according to any one of

[11] -

[13] , wherein the amount of the moisture-proof coating agent is 0.1 to 20%, preferably 0.1 to 10%, based on the combined weight of magnesium oxide and binder.

[0034]

[15] The edible ink composition according to any one of [1] to

[14] comprises another colorant having a color other than white.

[0035]

[16] The edible ink composition according to any one of [1] to

[15] comprises one or more additives commonly used in printing inks, such as drying speed regulators, plasticizers, wetting agents, tackifiers, ink gloss agents, thixotropic agents, and fragrances; possible additives include glycerin, triethyl citrate (TEC), triacetin, ethylene glycol, propylene glycol, resins, waxes, polyglycerin fatty acid esters, glycerin fatty acid esters, sucrose fatty acid esters, sorbitan fatty acid esters, lecithin, enzymatically degraded lecithin, polysorbate, silica (SiO2), starch, alcohol-insoluble cellulose fragrances, and / or combinations thereof.

[0036]

[17] A printing substrate printed with any one of the edible ink compositions described in [1] to

[16] ; preferably, the printing substrate is a solid food or a solid pharmaceutical preparation, the solid pharmaceutical preparation preferably being a hard capsule, soft capsule, tablet or capsule.

[0037]

[18] A method for preparing an edible ink composition, the method comprising the step of mixing components of an edible ink composition to provide an edible ink composition, the components being magnesium oxide, a binder, a solvent and any optional components such as additives; wherein the edible ink composition and its components are as described in any one of [1] to

[16] .

[0038]

[19] A method for printing an edible ink composition on a printing substrate, using an edible ink composition as described in any one of [1] to

[16] and the printing substrate.

[0039] The components of the edible ink composition of the present invention are described in more detail below.

[0040] (Magnesium oxide, MgO) Specification 3 / 14 pages 6 CN 121844013 A In the present invention, heavy magnesium oxide is used as a white pigment in the edible ink composition. Heavy magnesium oxide is industrially produced by the thermal decomposition of magnesium carbonate or magnesium hydroxide.

[0041] In the production process, magnesium oxide sintered at a calcination temperature of 600°C to 900°C is called "caustic calcined magnesite" or "caustic calcined magnesium oxide" or "light-calcined magnesium oxide," and its chemical reactivity is higher than that of so-called hard-calcined magnesium oxide produced at a calcination temperature of 1000°C to 1500°C.

[0042] Initially, the inventors of the present invention attempted to develop edible ink compositions using magnesium oxide produced at a calcination temperature of 600°C. However, it was found that when it was dispersed in a solvent with a binder, the viscosity of the edible ink composition increased over time, eventually hardening and becoming unusable.

[0043] It is speculated that when caustic calcination of magnesite (calcination temperature of 600°C) is used, it may even react with a small amount of moisture, turning into magnesium hydroxide over time, causing particles to adhere and form lumps.

[0044] However, this phenomenon is surprisingly suppressed by increasing the calcination temperature of magnesium oxide to above 600°C, and it has been found that inks with excellent stability over time can be produced.

[0045] The magnesium oxide used in this invention is produced at a calcination temperature of at least 700°C, preferably at least 800°C, more preferably at least 900°C, and even more preferably at least 925°C. Specific embodiments of the calcination temperature are 950°C and 1300°C.

[0046] Preferably, the magnesium oxide content of the edible ink composition is 65 wt% or less of the weight of the edible ink composition, preferably 20 to 65 wt%, more preferably 20 to 50 wt%.

[0047] Preferably, the edible ink composition does not contain nanoparticles.

[0048] Preferably, the dried ink of the edible ink composition is free of nanoparticles.

[0049] More preferably, the edible ink composition is free of nanoparticles, and the dried ink of the edible ink composition is free of nanoparticles.

[0050] The magnesium oxide used in this invention has a particle size suitable for ink application.

[0051] The particle size distribution of magnesium oxide can be characterized by D10 and / or D90 values. The D10 / D90 value indicates that 10% / 90% of the particles have a particle size smaller than the D10 / D90 value. Within the meaning of this invention, the % unit of any D10 / D90 value refers to a cumulative volume percentage.

[0052] In one embodiment, the particle size distribution D10 value of magnesium oxide is 2 μm or less, preferably 1.5 μm or less, more preferably 1.0 μm or less.

[0053] The particle size distribution D90 value of magnesium oxide is 20 μm or less, preferably 15 μm or less, more preferably 10 μm or less, even more preferably 5 μm or less, particularly 2 μm or less, even more particularly 1.5 μm or less, even more particularly 0.8 μm or less.

[0054] The maximum particle size of magnesium oxide used in this invention can be 20 μm or less.

[0055] The maximum particle size of magnesium oxide is preferably 15 μm or less, more preferably 10 μm or less, even more preferably 5 μm or less, particularly 2 μm or less, even more particularly 1.5 μm or less, even more particularly 0.8 μm or less.

[0056] The larger the size of the magnesium particles, the more difficult it is to keep the particles suspended without precipitation. Precipitated magnesium particles tend to roughen the surface of the printed matter after printing, often leading to changes in print quality and often destroying print quality. For example, if the particle size distribution D90 value exceeds 20 μm, magnesium oxide tends to precipitate in edible ink compositions.

[0057] From the perspective of product value, nanoparticles are preferably excluded for health reasons.

[0058] Therefore, in one embodiment, the particle size distribution D10 value of magnesium oxide is 0.1 μm or greater, and even the minimum particle size is 0.1 μm or greater; therefore, preferably, the particle size distribution D10 value of magnesium oxide is 0.1 to 2 μm, more preferably 0.1 to 1.5 μm, and even more preferably 0.1-1.0 μm; in particular, the particle size distribution D10 value of magnesium oxide is 2 μm or less, and the minimum particle size is 0.1 μm; more particularly, the D10 value is 1.5 μm or less, and the minimum particle size is 0.1 μm, and even more particularly, the D10 value is 1 μm or less, and the minimum particle size is 0.1 μm.

[0059] In another embodiment, the particle size distribution D10 value of magnesium oxide is greater than 0.1 μm, even the minimum particle size is greater than 0.1 μm; therefore, preferably, the particle size distribution D10 value of magnesium oxide is greater than 0.1 μm to 2 μm, more preferably greater than 0.1 μm to 1.5 μm, more preferably greater than 0.1 μm to 1 μm; even more preferably, the particle size distribution D10 value of magnesium oxide is 2 μm or less and the minimum particle size is greater than 0.1 μm; in particular, the D10 value is 1.5 μm or less and the minimum particle size is greater than 0.1 μm, especially the D10 value is 1 μm or less and the minimum particle size is greater than 0.1 μm.

[0060] Any values ​​of the particle size and particle size distribution of magnesium oxide described herein have been and can be measured and determined by laser diffraction with a detection wavelength of 650 nm and an emission wavelength of 405 nm. Preferably, the measurement has been performed with an aqueous dispersion of magnesium oxide and can be performed in this way. Preferably, the measurement has been performed at room temperature and can be performed in this way. The term "room temperature" as used herein refers to 24°C.

[0061] The particle size distribution measurement has been completed and can be performed as follows: Preparation of magnesium oxide aqueous dispersion: A sample for measurement is prepared by dispersing an appropriate amount of magnesium oxide in an aqueous solution of sodium hexametaphosphate (0.2 wt%) (Wako Pure Chemical Industries, Ltd.) in an external ultrasonic bath.

[0062] The dispersion is then placed in a particle size distribution analyzer, and the particle size distribution is measured while the sample is ultrasonically treated by a corresponding ultrasonic device built into the particle size distribution analyzer.

[0063] Measuring device: Partica LA-960V2 laser diffraction / scattering particle size distribution analyzer (Horiba Ltd.) Measurement unit: wet measurement Temperature: room temperature Light source: LD (laser diode, 650nm) and LED (light emission diode, 405nm) Particle size standard: volume Particle refractive index: 1.76 (real part), 0.00 (imaginary part) Solvent: 0.2wt% sodium hexametaphosphate aqueous solution Solvent refractive index: 1.333 (binder) Preferably, the binder is an edible film-forming and non-thermosetting polymer, the binder is soluble in alcohol, and even more preferably, the binder is hydroxypropyl cellulose (HPC), polyvinylpyrrolidone (PVP) or a mixture thereof.

[0064] Hydroxypropyl cellulose is a nonionic cellulose ether obtained from cellulose (pulp) which is widely present in nature, treated with sodium hydroxide, and then reacted with an etherifying agent such as propylene oxide.

[0065] Hydroxypropyl cellulose is used as a pharmaceutical additive for tablets, capsules, and granules, such as a lubricant, coating agent, disintegrant, and binder.

[0066] Polyvinylpyrrolidone is also used in the pharmaceutical field in Japan and as a coating agent for pharmaceutical tablets in the European Union (EU).

[0067] Therefore, no safety issues arise when these are used as binders for edible ink compositions.

[0068] Alternatively, shellac (an alcohol-soluble edible ink binder) can be used.

[0069] (Solvent) Preferably, the solvent is substantially volatile or evaporated and does not remain in the ink after the edible ink composition dries.

[0070] Preferably, the solvent is an alcohol or a mixture of alcohol and water, more preferably, the alcohol is ethanol, propanol, or butanol, preferably ethanol or butanol. Even more preferably, the alcohol is ethanol. The alcohol content of the mixture of alcohol and water is preferably at least 80% by volume, more preferably at least 85% by volume, and even more preferably at least 90% by volume. An example implementation is an alcohol-water mixture containing 99% or 95% vol% alcohol, such as a 99% or 95% vol% aqueous ethanol solution.

[0071] During the printing process itself, the edible ink composition can be further diluted with the desired amount of alcohol or water.

[0072] Highly polar solvents such as glycerin, ethylene glycol, and propylene glycol are also compatible with alcohols and can be mixed appropriately. The higher the carbon number, the lower the vapor pressure of the alcohol, so mixing appropriately can slow down the drying rate of the edible ink composition.

[0073] If the edible ink composition dries too quickly, glycerin, ethylene glycol or propylene glycol, urea, or any solvent-soluble sugar, such as sorbitol or fructose, can be added to the composition in appropriate amounts. These methods allow for adjustment of ink density and drying speed according to the temperature and humidity of the printing chamber.

[0074] (Other Additives) The edible ink composition may contain another colorant whose color is not white.

[0075] Magnesium oxide has two effects, one is whiteness, and the other is opacity, so magnesium oxide is ideal as both a white colorant and an opacifier. Therefore, when the edible ink composition contains only magnesium oxide as a colorant, the dried ink is opaque and white. When a color other than white is required, either or both of the two effects of magnesium oxide may still be required: its whiteness can brighten (also called brightening or highlighting) the desired non-whiteness of another non-white colorant, so it can act as both a whitening agent and a brightening or highlighting agent, and its opacity can cause any opacity of another non-white colorant, which may even be the sole source of opacity if the other non-white colorant itself does not introduce any opacity.

[0076] Preferably, any colorant contained in the edible ink composition has a non-white color.

[0077] In one embodiment, the edible ink composition does not contain titanium oxide (TiO2) as a white colorant.

[0078] In one embodiment, the edible ink composition is free of TiO2.

[0079] In one embodiment, the edible ink composition is free of calcium carbonate (CaCO3) as a white colorant.

[0080] In one embodiment, the edible ink composition is free of CaCO3.

[0081] In one embodiment, the edible ink composition is free of both TiO2 and CaCO3 as white colorants.

[0082] In one embodiment, the edible ink composition is free of both TiO2 and CaCO3.

[0083] In one embodiment, the edible ink composition is free of any white colorant other than magnesium oxide (also referred to as a white colorant).

[0084] If a non-white colored ink is required, an appropriate amount of colorant, such as ferric oxide or aluminum lake or other food colorant, whether pigment or dye, or solvent-soluble natural and tar dyes, may be added to the edible ink composition, or a portion of magnesium oxide may be substituted.

[0085] Other colorants used in the pharmaceutical or food industries may be used. Such colorants include, for example, lake tar dyes, water-soluble tar and natural dyes, caramel, cochineal dyes, shellac dyes, riboflavin, sodium iron chlorophyll, sodium copper chlorophyll, copper chlorophyll, toner, black iron oxide, squid ink pigments, etc.

[0086] In order to achieve a pearlescent effect, pearl pigments made from appropriate amounts of fish scale foil, shell pearl layer, or fine powders such as mica and silica are used.

[0087] The above-described edible ink composition containing magnesium oxide may contain one or more additives commonly used in printing inks, such as moisture-proof coating agents, drying speed regulators, plasticizers, wetting agents, tackifiers, ink gloss agents, thixotropic agents, and fragrances. Preferably, any additive is an edible additive.

[0088] Even in the presence of these additives, the edible ink composition of the present invention can fully achieve its purpose as a printing ink as stated in its specification, page 6 / 14, 9 CN 121844013 A.

[0089] For example, to provide a moisture-proof coating, enhance adhesive strength, provide ink gloss, or adjust ink hardness, resins such as solvent-soluble resins, such as rosin, waxes, polyglycerol fatty acid esters, glycerol fatty acid esters, sucrose fatty acid esters, dehydrated sorbitol fatty acid esters, lecithin, enzymatically degraded lecithin, or solvent-soluble polysorbates may be added.

[0090] In particular, the addition of a moisture-resistant coating agent can improve ink adhesion and increase reflectivity and whiteness.

[0091] Moisture-resistant coating agents that can be added to inks are fatty acid esters, C16 or higher alcohols, C12 or higher fatty acids, glycerides or mixtures thereof, which are soluble or miscible with alcohols but insoluble in water, or surfactants with an HLB of 6 or lower.

[0092] Specific examples of moisture-resistant coating agents include stearic acid, beeswax such as white beeswax, resins such as rosin, wood wax, cetyl alcohol, lanolin, lanolin alcohol, cetyl alcohol, stearyl alcohol, cetyl alcohol monostearate polyethylene glycol mixed wax, cetyl alcohol polysorbate 60 mixed wax, cetyl stearyl alcohol, isopropyl myristate, isopropyl linoleate, isopropyl palmitate, oleic acid, and vegetable oils such as olive oil and castor oil.

[0093] Stearic acid and beeswax are particularly preferred examples of moisture-resistant coating agents.

[0094] The amount of the moisture-proof coating agent is 0.1 to 20% by weight, preferably 0.1 to 10% by weight, based on the combined weight of magnesium oxide and binder (HPC or PVP, etc.).

[0095] Solvent-soluble plasticizers, such as glycerin, triethyl citrate (TEC), and triacetin, may also be added to reduce ink hardness.

[0096] Therefore, possible additives include glycerin, triethyl citrate (TEC), triacetin, ethylene glycol, propylene glycol, resins, waxes, polyglycerin fatty acid esters, glycerin fatty acid esters, sucrose fatty acid esters, sorbitan fatty acid esters, lecithin, enzymatically degraded lecithin, polysorbate, silica (SiO2), starch, alcohol-insoluble cellulose, fragrances, and / or combinations thereof.

[0097] To improve the adhesion of the ink, any type of polymeric thickener, thickening stabilizer, or solvent-soluble binder, such as zein, rosin, or glycerol ester of wood rosin, may be added.

[0098] (Weight ratio of components) The typical amount of solvent in the edible ink composition is 35 to 80 wt%, more preferably 40 to 75.5 wt%, wt% based on the weight of the edible ink composition.

[0099] The typical amount of binder in the edible ink composition is 0.5 to 25 wt%, more preferably 0.5 to 22.5 wt%, even more preferably 0.5 to 20 wt%, wt% based on the weight of the edible ink composition.

[0100] The typical amount of magnesium oxide in the edible ink composition is 10 to 60 wt%, more preferably 15 to 55 wt%, even more preferably 20 to 50 wt%, wt% based on the weight of the edible ink composition.

[0101] The typical range of the magnesium oxide / binder weight ratio in the edible ink composition is 1.9 to 105.

[0102] Preferably, after the edible ink composition is dried, the amount of magnesium oxide in the ink is 99 wt% or less, preferably 60 to 99 wt%, wt% based on the weight of the ink after the edible ink composition is dried.

[0103] Preferably, the solid content of the edible ink composition, i.e., the weight of the ink after the edible ink composition is dried, is 65 wt% or less of the weight of the edible ink composition, more preferably 20 to 65 wt%.

[0104] The typical amount of additives, particularly plasticizers, in the edible ink composition is 0 to 5 wt%, wt% based on the weight of the edible ink composition.

[0105] Preferably, the amounts of binder, solvent, magnesium oxide, and possibly plasticizers in the edible ink composition range as follows: (Page 7 / 14, CN 121844013 A) Binder: 0.5 to 20 wt%; MgO: 20 to 50 wt%; Solvent: 40 to 75.5 wt%; Plasticizer: 0 to 5 wt%; wherein wt% is based on the weight of the edible ink composition.

[0106] (Method for Preparing an Edible Ink Composition) Another subject of the present invention is a method for preparing an edible ink composition and all embodiments thereof, the method comprising the step of mixing components of an edible ink composition to provide an edible ink composition, the components being magnesium oxide, a binder, a solvent, and any optional components such as additives; wherein the edible ink composition and its components are as defined herein.

[0107] The mixing of the components may be carried out in any order.

[0108] Depending on the properties of magnesium oxide, the method may include the step of dispersing magnesium oxide in a solvent.

[0109] In one embodiment, a method for preparing an edible ink composition includes the steps of: (i) mixing magnesium oxide and a binder, (ii) adding a solvent to the mixture provided in (i), and (iii) dispersing the magnesium oxide in the solvent.

[0110] (Printing Method) Another subject of the invention is a method for printing an edible ink composition on a printing substrate and all embodiments thereof, wherein the edible ink composition and the printing substrate are as defined herein.

[0111] The method of printing an edible ink composition containing magnesium oxide onto a printing substrate (e.g., solid pharmaceutical preparations and solid food) is not limited and can be carried out according to known conventional methods.

[0112] For example, printing on capsules can be accomplished by diluting a stock solution of printing ink with the solvent described above as needed and using a gravure / offset printing press.

[0113] (Printing Object) The printing substrate can be a solid food or a solid pharmaceutical preparation, such as hard capsules, soft capsules, tablets, and capsules.

[0114] In the case of hard capsules, the capsule substrate can be any known material that can be used in pharmaceuticals and health foods, such as gelatin, pullulan, hydroxypropyl methylcellulose (HPMC), hydroxypropyl methylcellulose acetate succinate (HPMCAS), hydroxypropyl methylcellulose phthalate (HPMCP), ethyl acrylate methyl methacrylate copolymer, polyvinyl alcohol (PVA), starch-based materials, and combinations of these capsule substrates. HPMC capsules, gelatin capsules, and pullulan capsules are preferred. The capsules can be bundled or sealed. The capsules can also be colored with known colorants (preferably natural dyes).

[0115] Solid foods, such as sweets and candies, can also be used as printing substrates for the edible ink compositions of the present invention.

[0116] (Effects of the Invention) By using the above-described edible ink compositions containing magnesium oxide to print on the printing substrates (such as tablets, capsules, and capsules), clear white prints can be obtained. When dyes other than white are added to the edible ink compositions, colored prints can also be obtained. These prints also have the same peel resistance and other properties as conventional printing inks. Imprints made on printing substrates using an edible ink composition containing magnesium oxide and printing substrates printed using an edible ink composition containing calcium oxide (such as capsules) exhibit stability under light over time. The printed capsules also meet the properties, quality, and characteristics of capsules as defined in the Japanese Pharmacopoeia, namely, appearance, properties, and purity tests, and can be used for pharmaceutical or food purposes in exactly the same manner as conventional capsules. Instructions for Use 8 / 14 pages 11 CN 121844013 A

[0117] [Definitions] For propane-1,2,3-triol, all three commonly used names glycerol (glycerol, glycerine, glycerin) are synonyms herein.

[0118] The term edible ink composition herein refers to a liquid composition comprising magnesium oxide, a binder, and a solvent; the solid remaining after drying, i.e., after the volatile components of the edible ink composition have evaporated, is generally referred to herein as ink.

[0119] Unless otherwise stated, the unit “um” is the same as the unit “μm”, i.e., “micrometer”.

[0120] The invention is described in detail based on the following examples.

[0121] Needless to say, these examples do not limit the invention.

[0122] [Examples] 1. Magnesium Oxide Table 1 describes the manufacturing conditions and particle size distribution of the magnesium oxide products (MS-0, MS-1, and MS-2F) used in the following examples.

[0123] MS-0: Magnesium oxide (heavy) (food additive) Tomita Pharmaceutical Co., Ltd.

[0124] MS-1: Magnesium oxide (heavy) (food additive) Japan Natural Energy & Resources Co., Ltd.

[0125] MS-2F: Fine-particle magnesium oxide (heavy) (food additive) Japan Natural Energy & Resources Co., Ltd.

[0126] Table 1 (*) The definition of D50 / D100 values ​​is similar to the definition of D10 / D90 values ​​given herein.

[0127] 2. Preparation of Edible Ink Compositions The edible ink compositions (samples 1 to 15) were prepared as follows: 1) Magnesium oxide powder and HPC powder (samples-1 to-13 and sample-15) or PVP powder (sample-14) were mixed in the weight ratio shown in Table 2 and then placed in a 100 ml homogenizer container.

[0128] 2) The amount of 95 vol% aqueous ethanol solution shown in the table was added to the mixture in 1) (at room temperature).

[0129] 3) The mixture in 2) was thoroughly mixed with a glass rod.

[0130] 4) The magnesium oxide powder was dispersed in a homogenizer (ACE HOMOGENIZER, AM-8) at 6000 to 8000 rpm for 5 minutes.

[0131] 5) The dispersion in 4) was repeated twice.

[0132] 6) Place the prepared edible ink composition into a sealable container and store it at room temperature to prevent solvent evaporation.

[0133] White edible ink can be prepared similarly regardless of whether HPC or PVP is used as the binder. Specification 9 / 14 pages 12 CN 121844013 A

[0134] Table 2 *“Solid content” refers to the weight of the ink after the edible ink composition has dried.

[0135] The following products were used as adhesives: HPC (Nippon Soda, product name: Cerny SSL); PVP (polyvinylpyrrolidone, BASF, product name: Kolidon 90F).

[0136] 3. Long-term stability test The method for testing the long-term stability of the edible ink composition is as follows: The prepared edible ink solution was placed in a polypropylene container and sealed, and the container was stored at room temperature. The condition of the ink solution was observed after 2 weeks.

[0137] As a comparison product, the ready-made white ink CFWhite (San-Ei Gen FFI, Inc.) was used, in which TiO2 was used as the white pigment.

[0138] The edible ink composition containing magnesium oxide (MS-O) produced at a calcination temperature of 600°C (sample 1) cured 5 days after preparation, rendering it unusable. However, no abnormalities were observed in the comparison product and other samples (samples 2 to 15), in particular, no curing.

[0139] Table 3 4. Ink Adhesion Test The peel strength of the ink was measured as follows: Two tapes with a thickness of approximately 50 μm were pasted parallel to each other on a gelatin sheet, with a gap of approximately 1 cm between the two tapes. Therefore, the two tapes with a thickness of 50 μm acted as "spacers" to make the ink thickness 50 μm. Then, the ink solution (page 10 / 14, CN 121844013 A) was dropped onto the gelatin sheet shown in the gap between the two tapes. A round glass rod was slid across the surface of the two tapes while passing through the gap between the two tapes to quickly apply the ink.

[0140] In this way, an ink rod with a thickness of approximately 50 μm was applied to the gelatin sheet.

[0141] Nichiban cellophane tape was applied to the part that was applied after 10, 30, 60, 120, 180, 240 and 600 seconds after the application and then removed immediately.

[0142] The peel strength of the ink was evaluated as follows: 〇: The coated ink remained on the surface of the gelatin sheet; ×: The coated ink peeled off the surface of the gelatin sheet.

[0143] 〇 indicates pass, × indicates failure.

[0144] The results are shown in Table 4.

[0145] Compared with the control product, all inks from samples 2 to 15 provided the same or better adhesion and drying speed.

[0146] Table 4 5. Ink Color Analysis Color difference measurement was performed as follows: The ink samples and the white ink CF White (San-Ei Gen FFI, Inc.) made of TiO2, which served as the control product, were bar coated as described in “4. Ink Adhesion Test” above. After the ink samples dried, the L value was measured using an X-Rite Ci7600 colorimeter and compared with the control product to calculate the color difference (ΔL).

[0147] Table 5 L values ​​represent the components of brightness and whiteness; the higher the L value, the stronger the whiteness.

[0148] CF White uses shellac as its binder. Since its color is pale yellow, the ink is also slightly yellowish-white. Specification 11 / 14 pages 14 CN 121844013 A On the other hand, the white inks of samples 5 to 15 of the present invention are pure white. Therefore, whiteness can be compared by ΔL.

[0149] 6. Adjusting the drying speed If the solvent is only aqueous ethanol, the ink on the printing press will evaporate quite quickly, and depending on the printing press used, the edible ink composition may dry before being transferred to the printing substrate, which may result in a decrease in print quality. In this case, glycerin or both water and glycerin can be added to the edible ink composition to slow down the drying speed.

[0150] Table 6 shows examples of samples (samples 16 to 20) with the drying speed adjusted by glycerin or both water and glycerin.

[0151] Table 6 *“Solid content” refers to the weight of the dried ink after the edible ink composition has dried.

[0152] The ink adhesion test (point 4 above), ink color analysis (point 5 above), and long-term stability test (point 3 above) of samples 16 to 20 were evaluated in the same manner as described above. Table 7 shows the results.

[0153] The addition of glycerin or glycerin and water had no effect on long-term stability or whiteness, but the adhesion strength was assessed as × for a maximum of 120 or 180 seconds after printing. This means that the ink remained wet after 120 or 180 seconds of drying. This indicates that by adding glycerin and / or water, the drying rate of the edible ink composition can be slowed down as needed.

[0154] Table 7 Specification 12 / 14 pages 15 CN 121844013 A 7. Moisture-proof edible ink composition Preparation method of moisture-proof edible ink composition According to the weight ratio of the ink composition given in Table 8, ethanol is placed in a container, stearic acid or refined beeswax (these are called wax components), and the mixture is heated to 50°C to completely dissolve the wax components. Next, magnesium oxide is added, and it is dispersed in a homogenizer at 8000 rpm for 1.5 minutes. Then, HPC is added little by little while gently stirring until it is completely dissolved. It is dispersed in a homogenizer at 8000 rpm for 5 minutes to prepare the ink composition.

[0155] Table 8 Moisture-proof Edible Ink Composition wt.% The following products are used as components of the moisture-proof edible ink composition containing magnesium oxide: MgO (MS-2F): Japan Natural Energy & Resources Co. Ltd.; HPC (Cerny): Nippon Soda Co. Ltd.; Stearic acid: NOF CORPORATION; Refined beeswax: CERARICA NODA Co. Ltd.

[0156] 8. Whiteness and Adhesion of Moisture-proof Edible Ink Composition Place two pieces of tape about 50 μm thick parallel to each other on a glass plate, leaving a 1 cm gap between them. Using the tape on both sides as spacers, drop the ink prepared above onto the glass plate between the tapes, and apply the ink to the glass plate between the tapes in one go using a hard rubber squeegee (page 13 / 14 of the instruction manual, CN 121844013 A). Due to the presence of spacers, the thickness of the ink strip applied between the spacers is approximately 50 μm, and the solid content of the ink is approximately 27%. Therefore, once the ink dries and the tape is peeled off, a dried ink strip with an estimated thickness of approximately 15 μm is obtained.

[0157] On the same day of drying, the L value of the color of the dried ink strip was measured using a Ci7600 X-Rite colorimeter and set as the initial value (T=0 days). The glass plate with the dried ink strip was stored at 25°C and 75% relative humidity, and the L value was measured on days 1, 2, 5, 7, 12, and 16. The L value represents whiteness / brightness. The difference (ΔL) between the L value after storage and the initial value is shown in Table 9.

[0158] Table 9 (*) L value not measured (**) At this point, the quality of the dried ink has deteriorated so much that the measurement is no longer meaningful.

[0159] Results: The decrease in L value of the dried ink containing stearic acid or beeswax was significantly less than the corresponding decrease in L value of the dried ink without wax components (sample 21). Therefore, after being stored under humid conditions for a period of time, the dried ink without wax components showed significantly lower whiteness than the dried ink containing wax components.

[0160] The dried ink containing magnesium oxide and stearic acid or beeswax also showed better adhesion than the ink composition without wax components.

[0161] Furthermore, the dried ink showed increased reflectivity and whiteness (Table 10, L values ​​at T=0).

[0162] Table 10 (Industrial Applicability) Since the edible ink composition of the present invention does not contain titanium oxide, it is possible to print with high health safety and high added value, which is what society demands. In addition, since magnesium oxide has good whiteness and hiding power, white and other colors can be printed clearly. The edible ink composition also has good adhesion to the surface of the printing substrate.

[0163] Therefore, the edible ink composition of the present invention can be used as a printing ink for the surface of solid food and solid pharmaceutical preparations (especially capsules, tablets and pouches, especially capsules). Specification 14 / 14 pages 17 CN 121844013 A.

Claims

1. An edible ink composition comprising magnesium oxide, a binder, and a solvent, The magnesium oxide is produced at a calcination temperature of at least 700°C, and the edible ink composition is free of titanium oxide.

2. The edible ink composition according to claim 1, wherein... The magnesium oxide is produced at a calcination temperature of at least 800°C.

3. The edible ink composition according to claim 1 or 2, wherein the D90 value of magnesium oxide is 20 μm or less.

4. The edible ink composition according to any one of claims 1 to 3, wherein the particle size distribution D90 value of magnesium oxide is 1 to 15 μm.

5. The edible ink composition according to any one of claims 1 to 4, wherein the particle size distribution D10 value of magnesium oxide is 0.1 μm or greater.

6. The edible ink composition according to any one of claims 1 to 5, wherein after drying, the amount of magnesium oxide in the ink is 99 wt% or less, preferably 60 to 99 wt%, said wt% based on the weight of the ink after drying the edible ink composition.

7. The edible ink composition according to any one of claims 1 to 6, wherein the solid content of the edible ink composition is 65 wt% or less of the weight of the edible ink composition, preferably 20 to 65 wt%.

8. The edible ink composition according to any one of claims 1 to 7, wherein the solvent substantially evaporates or evaporates and does not remain in the ink after the edible ink composition has dried.

9. The edible ink composition according to any one of claims 1 to 8, wherein the solvent is an alcohol or a mixture of alcohol and water, wherein the alcohol is preferably ethanol, propanol or butanol, more preferably ethanol or butanol; and even more preferably, the alcohol is ethanol.

10. The edible ink composition according to any one of claims 1 to 9, The adhesive is preferably an edible film-forming and non-thermosetting polymer or shellac, and the adhesive is soluble in alcohol. When the adhesive is a non-thermosetting polymer, the adhesive is hydroxypropyl cellulose, polyvinylpyrrolidone, or a mixture thereof.

11. The edible ink composition according to any one of claims 1 to 10, comprising a moisture-proof coating agent.

12. The edible ink composition according to claim 11, wherein the moisture-proof coating agent is a higher fatty acid ester soluble or miscible with alcohol but insoluble in water, C 16 Or higher alcohols, C 12 Or higher fatty acids, glycerides, or mixtures thereof, or surfactants with an HLB value of 6 or less.

13. The edible ink composition according to claim 11 or 12, The moisture-proof coating agent mentioned therein is stearic acid, beeswax such as white beeswax, resin such as rosin, wood wax, cetyl alcohol, lanolin, lanolin alcohol, cetyl alcohol, stearyl alcohol, cetyl alcohol monostearate polyethylene glycol mixed wax, cetyl alcohol polysorbate 60 mixed wax, cetyl stearyl alcohol, isopropyl myristate, isopropyl linoleate, isopropyl palmitate, vegetable oil such as oleic acid, olive oil, castor oil.

14. The edible ink composition according to any one of claims 11 to 13, wherein Based on the combined weight of the magnesium oxide and the adhesive, the amount of the moisture-proof coating agent is 0.1 to 20%, preferably 0.1 to 10%.

15. The edible ink composition according to any one of claims 1 to 14, comprising another colorant having a color other than white.

16. The edible ink composition according to any one of claims 1 to 15, comprising one or more additives commonly used in printing inks, such as drying speed regulators, plasticizers, wetting agents, tackifiers, ink gloss agents, thixotropic agents, and fragrances; possible additives include glycerol, triethyl citrate (TEC), triacetin, ethylene glycol, propylene glycol, resins, waxes, polyglycerol fatty acid esters, glycerol fatty acid esters, sucrose fatty acid esters, sorbitan fatty acid esters, lecithin, enzymatically degraded lecithin, polysorbate, silica (SiO2), starch, alcohol-insoluble cellulose, fragrances, and / or combinations thereof.

17. A printing substrate printed with an edible ink composition according to any one of claims 1 to 16; preferably, the printing substrate is a solid food or solid pharmaceutical preparation, wherein the solid pharmaceutical preparation is preferably a hard capsule, soft capsule, tablet or capsule capsule.

18. A method for preparing an edible ink composition, the method comprising the step of mixing components of the edible ink composition to provide an edible ink composition according to any one of claims 1 to 16, said components being magnesium oxide, a binder, a solvent, and any optional components such as additives.

19. A method for printing an edible ink composition on a printing substrate, using the edible ink composition as described in any one of claims 1 to 16 and the printing substrate.