Use of a stearic acid salt for improving the surface of sugar-coated solid forms

Abstract

The invention relates to a solid form coated with a sugar-coating composition, said sugar-coating composition comprising a crystallizable material and a stearic acid salt like magnesium stearate. The invention also relates to a sugar-coating composition comprising a stearic acid salt, and to a process for coating solid cores using the same. The invention also relates to the use, for improving the surface of a sugar-coating layer of a sugar-coated solid form, comprising including a stearic acid salt in said sugar-coating layer.

Description

DescriptionTitle: Use of a stearic acid salt for improving the surface of sugar-coated solid formsTechnical Field

[0001] The invention pertains to the field of sugar-coating of solid forms, in particular of tablets and chewing-gums.Background Art

[0002] Coating is the process where coating material is applied to the surface of solid forms to achieve the desired properties over the uncoated variety e.g., for improving the visual aspect, the odor, the taste, the stability, the ease of swallowing, the mechanical resistance of the solid form, for protecting the solid form from the gastric environment, or for modifying release properties of an active ingredient.

[0003] There are two main processes for tablet coating: sugar-coating and film coating.

[0004] Film coating is single-stage coating process that needs a relatively short time and so is favored over sugar-coating in the pharmaceutical field. Film coating is the deposition of a thin film of polymer (between 20 and 100 pm) applied mainly to tablets.

[0005] Sugar-coated solid forms are visually more appealing, and generally have a pleasant, sweet taste. However, unlike film coating, sugar-coating is a more laborious multistep process. The process of sugar-coating usually involves various steps e.g., filmcoating, sugar-coating as such, smoothing, coloring, polishing and printing, leading to final tablet weight increases of up to 30%-50%, significantly increasing tablet size.

[0006] Film-coating consists in applying a seal coat over the solid core to protect against water penetration into the tablet from the sugar-coatings to follow. Hence, it offers good stability of product and can also strengthen the tablet core. Application of a film former (e.g., arabic gum) onto the solid cores is also often used to promote the adhesion of the sugar- coating layer. The latter is often referred to as a “gumming” step. Film-coating may consist of Shellac, cellulose acetate phthalate (CAP), polyvinylacetate phthalate (PVAP), hydroxyl propyl cellulose (HPC), hydroxypropyl methylcellulose (HPMC), or Zein (a corn protein derivative).

[0007] Sugar-coating as such is regarded as the first major step in sugar-coating process. It involves the application of large quantities of sugar-coating composition(s) to the solid core, significantly increasing the solid cores weight. Sugar-coating provides the rapid buildup necessary to round up the tablet edge. It also provides the foundation for smoothingand color coating with any weakness in the final sugar coat often being attributable to weaknesses in the sugar-coating.

[0008] Smoothing is applied in order to smooth out sugar-coated rough surfaces and to increase solid cores bulk to desired size. Smoothing syrup generally consists of a sugar- coating composition having 60% - 70 wt.% of sugar solid. In some cases, syrup also comprises acacia, gelatin, pigments, starch, or opacifier. Smoothing is performed many times (about 10 cycles), until tablets are suitable for the next (e.g., coloring) phase.

[0009] When desired, coloring is typically achieved by adding pigments in the sugar- coating composition, or in the smoothing syrup.

[0010] Polishing gives the characteristic surface shine and tablet elegance. Polishing is performed in polishing pan using the beeswax, carnauba wax, and candelila wax mixture.

[0011] There has been a constant need for improving the surface of sugar-coated solid forms, for aesthetic reasons and / or because it can facilitate some of the steps of the sugar- coating process. For example, providing solid forms with a sugar-coating whose surface is as regular as possible will facilitate and accelerate the smoothing step.Technical Problem

[0012] It was an object of the present invention to improve the surface of sugar-coated solid forms, in particular to improve the smoothness of the sugar-coating layer.

[0013] It was another object of the present invention to reduce the sugar-coated process time.

[0014] It was an object of the present invention to solve the above-mentioned problem by providing a solution that has other required properties for this kind of application, for example in terms of safety and ease of use.Presentation of the Invention

[0015] The inventors solved the above-mentioned problem(s) by providing a sugar- coating composition that comprises, further to the sugar or sugar alcohol (crystallizable material), a stearic acid salt (e.g., magnesium stearate). In doing so, the inventors were able to increase the smoothness of the coated solid forms, thus reducing the time needed for smoothing the sugar-coated solid forms.

[0016] The smoothness obtained was even as good as the one obtained on sugar-coated products from the market (See Figure 1 , and in particular by comparison with the ibuprofen sugar-coated tablets), meaning that a smoothing step is not even required.

[0017] Furthermore, the opacity of the sugar-coating composition according to the disclosure is excellent, thus allowing to get rid of titanium dioxide (TiCh), which is particularly advantageous considering that the use of TiC>2 as a food additive is now prohibited in Europe.

[0018] The coating composition useful to the invention is particularly suitable for use in the coating process developed by the Applicant and described in WO2018 / 234248. As compared to traditional sugar-coating process, this sugar-coating process is very fast.Summary of the invention

[0019] The invention thus first relates to a solid form coated with a sugar-coating composition, said sugar-coating composition comprising a crystallizable material and a stearic acid salt, preferably magnesium stearate.

[0020] Preferably, said crystallizable material is selected from sugars, sugar alcohols, or from any mixture thereof. Preferably said crystallizable material is selected from xylitol, sucrose, erythritol, mannitol, dextrose, isomalt, maltitol, sorbitol, or from any mixture thereof. Still preferably said crystallizable material is selected from xylitol, mannitol, or from any mixture thereof.

[0021] Preferably, said stearic acid salt is an alkali or alkaline-earth metal salt of stearic acid, or a mixture thereof. Preferably, said stearic acid salt is selected from magnesium stearate, calcium stearate, sodium stearate or from any mixture thereof. Still preferably, said stearic acid salt is selected from magnesium stearate, calcium stearate, or from any mixture thereof. Still preferably, said stearic acid salt is magnesium stearate.

[0022] It is reminded that the term “stearic acid” refers to stearic acid per se, but also to mixtures of stearic acid and palmitic acid in variable proportions (8thEdition of Handbook of Pharmaceutical Excipients).

[0023] Preferably, said sugar-coating composition further includes a polymer binder.

[0024] The invention also relates to a sugar-coating composition that consists of:(a) solids, said solids consisting of:(a.1) from 80.0 to 95.0% of a crystallizable material selected from sugars, sugar alcohols or any mixture thereof, preferably from 85.0 to 95.0%, preferably from 86.0 to 94.0%, preferably from 87.0 to 93.0%, preferably from 88.0 to 92.0%, preferably from 89.0 to 91.0%, for example from 85 to 90%, or from 86 to 90%, or of 90%;(a.2) from 4.0 to 19.0% of a stearic acid salt (e.g., magnesium stearate), preferably from 4.0 to 18.0%, preferably from 4.0 to 17.0%, preferably from 4.0 to 16.0%, preferably from 4.0 to 15.0%, preferably from 4.0 to 14.0%, preferably from 4.0 to 13.0%, preferably from 4.0 to 12.0%, preferably from 4.0 to 11.0%, preferably from 4.0 to 10.0% for example 4.0% or6.0%, or 8.0% or 10.0%;(a.3) from 1.0 to 10.0% of a polymer binder, preferably from 1.0 to 9.0%, preferably from 1.0 to 8.0%, preferably from 1.0 to 7.0%, preferably from 1.0 to 6.0%, preferably from 1.0 to 5.0%, preferably from 1.0 to 4.0%, preferably from 2.0 to 4.0%, preferably from 3.0 to 4.0%, preferably 4%;(a.4) optionally no more than 3.0% of TiC>2, preferably no more than 2.0%, preferably no more than 1.5%, preferably no more than 0.010%, preferably no more than 0.005%, preferably no TiCh;(a.5) optionally up to 1.0% of pigments, preferably up to 0.5%, preferably up to 0.10%, preferably up to 0.05%, preferably up to 0.010%, preferably up to 0.005%;(a.6) optionally no more than 3.0 % of other ingredients, preferably no more than 2.0%, preferably no more than 1.0%, preferably no more than 0.5%, preferably no more than 0.10%, preferably no more than 0.005%, still preferably no other ingredient; the sum of the percentages of from (a.1) to (a.6) being expressed by weight with respect to the total weight of solids, and their sum being equal to 100%; and,(b) optionally a solvent, preferably water.

[0025] Preferably said crystallizable material is selected from xylitol, sucrose, erythritol, mannitol, dextrose, isomalt, maltitol, sorbitol, or from any mixture thereof. Still preferably said crystallizable material is selected from xylitol, mannitol, or from any mixture thereof.

[0026] Preferably, said stearic acid salt is an alkali or alkaline-earth metal salt of stearic acid, or a mixture thereof. Preferably, said stearic acid salt is selected from magnesium stearate, calcium stearate, sodium stearate or from any mixture thereof. Still preferably, said stearic acid salt is selected from magnesium stearate, calcium stearate, or from any mixture thereof. Still preferably, said stearic acid salt is magnesium stearate.

[0027] The invention also relates to a sugar-coating process comprising coating solid cores with a sugar-coating composition according to the disclosure.

[0028] The invention also relates to the use of a stearic acid salt in the sugar-coating layer of a sugar-coated solid form, for improving the surface of said sugar-coating layer. Preferably, said use is for improving the color, and / or increasing the brightness, and / or increasing the opacity, and / or increasing the smoothness, and / or decreasing the roughness and / or decreasing the rugosity of said coating layer. Still preferably, said use is for improving the smoothness, and / or decreasing the roughness and / or decreasing the rugosity of said sugar-coating layer.

[0029] The invention also relates to the use of a composition comprising a crystallizable material and a stearic acid salt for sugar-coating solid cores.Brief Description of Drawings

[0030] Other features, details and advantages will be shown in the following detailed description and on the figures.Fig. 1

[0031] [Fig. 1] is a graph showing rugosity measurement performed on sugar-coated solid forms from the market, on solid forms coated with a sugar-coating composition according to the disclosure or with a comparative sugar-coating composition.Fig. 2

[0032] [Fig. 2] is a graph showing the coating thickness of solid forms coated with a sugar- coating composition according to the disclosure or with a comparative sugar-coating composition.Fig. 3

[0033] [Fig. 3] are graphs showing the viscosity of various coating formulations, prepared at 60% solids, room temperature or at 70% solids, 70°C.Fig. 4

[0034] [Fig. 4] are graphs showing the turbidity of various coating formulations, prepared at 60% solids, room temperature or at 70% solids, 70°C.Description of Embodiments

[0035] Figures and the following detailed description contain, essentially, some exact elements. They can be used to improve the understanding of the invention and, also, to define the invention if necessary.

[0036] It must be noted that, as used in the specification and the appended claims, the singular form "a," "an," and "the" comprise plural referents unless the context clearly indicates otherwise, and means “at least one” or “one or more”. For example, reference to a component in the singular is intended to comprise a plurality of components. Thus, “a” crystallizable material or “a” stearic acid salt, means “one or more” crystallizable materials or “one or more” stearic acid salts, respectively.

[0037] The term "comprising" is synonymous with "including". These terms are inclusive and open-ended and do not exclude the presence of additional, unrecited features, as long as they do not render the disclosed or claimed subject-matter unworkable.

[0038] When the wording "consist of" is used, then no further features are present in the disclosed or claimed subject-matter apart from the ones following said wording.

[0039] Where the term “comprising” or one of its synonymous is used herein, the presently disclosed or claimed subject-matter can include the use of “consisting of’.1. Solid forms coated with a suqar-coatinq composition comprisinq amaterial, and a stearic acid salt

[0040] The disclosure thus first relates to a solid form coated with a sugar-coating composition, said sugar-coating composition comprising a crystallizable material and a stearic acid salt.In other words, it relates to a solid form comprising a solid core and at least one sugar- coating layer, said sugar-coating layer being obtained from a sugar-coating composition comprising a crystallizable material and a stearic acid salt. Preferably, said sugar-coating layer is an outer layer.

[0041] In sugar-coating, the term “solid form” classically refers to any solid presentation of substances. Typical examples are tablets, hard capsules, soft capsules, pellets, microspheres, granules, seeds, cookies, breakfast cereals, confectionery such as chewing gums, boiled candies, chewing candies, gummies, chocolates, fruits and vegetables, or products in the form of powders and / or crystals. These solid forms may, for example, be intended for food, pharmaceutical, veterinary, or cosmetic use. They can be intended for humans, adults or children, or for animals. They may also be intended for chemical or agrochemical use, although solid forms intended to be ingested (i.e. , “oral solid forms”) are preferred in the instant disclosure. Preferably, the solid forms according to the disclosure are selected from tablets and chewing gums.

[0042] In sugar-coating processes, the solid forms to be coated are classically referred to as “solid cores”. Said solid cores may be uncoated or already coated with one or more layer(s) of e.g., film-coating, or even sugar-coating, said layers being preferably formed in the same equipment as the one used for carrying out the sugar-coating process according to the disclosure.

[0043] Thus, the solid form coated with a sugar-coating composition according to the present disclosure may further comprise one or more inner coating layer(s), notably filmcoating and / or sugar-coating layers. In particular, it is coated with “a” sugar-coating composition of the present disclosure, which means that it is coated with “at least one”, or “one or more” sugar-coating compositions of the present disclosure. Preferably, the solid form coated with a sugar-coating composition of the disclosure, does not comprise any other sugar-coated layer i.e., obtained from a composition which is not according to the present disclosure.

[0044] As used herein, the terms “solid form coated with a sugar-coating composition” is also designated as “sugar-coated solid form”.

[0045] The sugar-coating composition of the present disclosure comprises a stearic acid salt and a crystallizable materials.

[0046] The stearic acid salt according to the disclosure is preferably an alkali or alkaline- earth metal salt of stearic acid, or a mixture thereof. Preferably, said stearic acid salt is selected from magnesium stearate, calcium stearate, sodium stearate or from any mixture thereof. It is preferably selected from magnesium stearate, calcium stearate, or from any mixture thereof. It is still preferably magnesium stearate.

[0047] Still preferably, in the sugar-coating composition according to the disclosure, the stearic acid salt(s) entirely consist of an alkali or alkaline-earth metal salt of stearic acid, or a mixture thereof. Preferably, in the sugar-coating composition according to the disclosure, the stearic acid salt(s) entirely consist of magnesium stearate, calcium stearate, sodium stearate or a mixture thereof. Preferably, in the sugar-coating composition according to the disclosure, the stearic acid salt(s) entirely consist of magnesium stearate, calcium stearate, or a mixture thereof. Still preferably, in the sugar-coating composition according to the disclosure, the stearic acid salt entirely consists of magnesium stearate i.e. , magnesium stearate is the sole stearic acid salt of the sugar-coating composition.

[0048] Preferably, the stearic acid salt (e.g., magnesium stearate) according to the disclosure has a specific surface area equal to or higher than 1 m2 / g, preferably equal to or higher than 2 m2 / g, preferably equal to or higher than 3 m2 / g, preferably equal to or higher than 4 m2 / g, preferably equal to or higher than 5 m2 / g, preferably equal to or higher than6 m2 / g, preferably equal to or higher than 7 m2 / g. It is preferably equal to or lower than30 m2 / g, preferably equal to or lower than 25 r i2 / g, preferably equal to or lower than 20 m2 / g, preferably equal to or lower than 15 m2 / g, preferably equal to or lower than 14 m2 / g, preferably equal to or lower than 13 m2 / g, preferably equal to or lower than 12 m2 / g, preferably equal to or lower than 11 m2 / g, preferably equal to or lower than 10 m2 / g, preferably equal to or lower than 9 m2 / g. It s for example equal to 8 m2 / g. This specific surface area may be determined by the person skilled in the art by the BET (Brunauer, Emmett and Teller) method. It can for example be determined by way of a specific surface analyzer (e.g., BECKMAN-COULTER, type SA3100), based on a nitrogen absorption test on the surface of the product subjected to analysis, following the technique described in the article BET Surface Area by Nitrogen Absorption from S. BRUNAUER et al. (Journal of American Chemical Society, 60, 309, 1938). The BET analysis is performed at 3 points.

[0049] Preferably, the amount of stearic acid salt (e.g., magnesium stearate) of the sugar- coating composition according to the disclosure is equal to or higher than 1%, said percentage being expressed by weight with respect to the total weight of solids of said sugar-coating composition. It is preferably equal to or higher than 2%, preferably equal to or higher than 3%, preferably equal to or higher than 4%, preferably equal to or higher than 5%, preferably equal to or higher than 6%, preferably equal to or higher than 7%, preferably equal to or higher than 8%. It is in general equal to or lower than 20%, preferably equal to or lower than 19%, preferably equal to or lower than 18%, preferably equal to or lower than 17%, preferably equal to or lower than 16%, preferably equal to or lower than 15%, preferably equal to or lower than 14%, preferably equal to or lower than 13%, preferably equal to or lower than 12%, preferably equal to or lower than 11%, preferably equal to or lower than 10%. It is for example equal 4% or equal to 6%, or equal to 8% or equal to 10%.

[0050] In the instant disclosure, the terms “solids” refers to ingredients other that solvents.

[0051] The sugar-coating composition of the present disclosure comprises a stearic acid salt and a crystallizable materials, said crystallizable material consisting of one or more crystallizable substance(s).

[0052] The terms “crystallizable material” classically refer, in sugar-coating field, to a substance or mixture of substances capable of crystallizing by evaporation of a solvent in which it is dissolved, during the sugar-coating process. This crystallizable material forms a hard crystalline coating at the surface of the solid cores. Sugar-coating should not be mistaken with film-coating. In film-coating, a composition based on a film-forming polymer (e.g., cellulose derivatives such as hydroxypropylmethylcellulose (HPMC), Polyvinyl alcohol (PVA)) is used, and not a composition of a crystallizable material (also sometime referred to as “syrup”). This film-forming composition forms a thin film at the surface of the tablets that is not crystalline.

[0053] Preferably, the crystallizable material according to the disclosure is selected from sugars, sugar alcohols, or from any mixture thereof, still preferably selected from monomers, dimers, or from any mixture thereof.

[0054] Preferably, the crystallizable material according to the disclosure is selected from xylitol, sucrose, erythritol, mannitol, dextrose, isomalt, maltitol, sorbitol, or from any mixture thereof. Still preferably, the crystallizable material according to the disclosure is selected from xylitol, mannitol, or from any mixture thereof. Still preferably, the crystallizable material according to the disclosure is xylitol.

[0055] Still preferably, in the sugar-coating composition according to the disclosure, the crystallizable material(s) entirely consist of sugars, sugar alcohols, or a mixture thereof.Preferably, in the sugar-coating composition according to the disclosure, the crystallizable material(s) entirely consist of xylitol, sucrose, erythritol, mannitol, dextrose, isomalt, maltitol, sorbitol, or a mixture thereof. Preferably, in the sugar-coating composition according to the disclosure, the crystallizable material(s) entirely consist of xylitol, mannitol, or a mixture thereof. Still preferably, in the sugar-coating composition according to the disclosure, the crystallizable material entirely consists of xylitol i.e., xylitol is the sole crystallizable material of the sugar-coating composition.

[0056] Preferably, the amount of crystallizable material of the sugar-coating composition according to the disclosure is equal to or higher than 50%, said percentage being expressed by weight with respect to the total weight of solids of said sugar-coating composition. It is preferably equal to or higher than 70%, preferably equal to or higher than 80%, preferably equal to or higher than 85%, preferably equal to or higher than 86%, preferably equal to or higher than 87%, preferably equal to or higher than 88%, preferably equal to or higher than 89%. It is in general equal to or lower than 99%, preferably equal to or lower than 95%, preferably equal to or lower than 94%, preferably equal to or lower than 93%, preferably equal to or lower than 92%, preferably equal to or lower than 91%. It is for example from 85% to 90%, or from 86% to 90%, or of 90%.

[0057] Preferably, the weight ratio of crystallizable material : stearic acid salt is selected from 2: 1 to 50: 1 , preferably from 3: 1 to 45: 1 , preferably from 4: 1 to 40: 1 , preferably from 5: 1 to 35:1 , preferably from 5:1 to 30:1 , preferably from 5:1 to 25:1 , preferably from 6:1 to 20:1 , preferably from 7:1 to 15:1 , preferably from 7:1 to 12:1 , preferably from 7:1 to 10:1. It is for example equal to 9:1 or equal to 11 :1 , or equal to 16:1 or equal to 24:1.

[0058] Preferably, the sugar-coating composition according to the disclosure further include a polymer binder.

[0059] This polymer binder may be selected from any suitable starch compounds, PVA, Arabic gum, or from any mixture thereof. It is preferably selected from starch compounds, still preferably hydrolyzed functionalized starches.

[0060] The expression “starch compound” classically refers to a substance obtained from starch. It is reminded that the expression “starch” classically refers to the starch isolated from any suitable botanical source, by any technique well known to those skilled in the art. Isolated starch typically contains no more than 3% of impurities; said percentage being expressed in dry weight of impurities with respect to the total dry weight of isolated starch. These impurities typically comprise proteins, colloidal matters and fibrous residues. Suitable botanical source includes for instance legumes, cereals, and tubers. The starch compounds according to the disclosure can be derived from any suitable botanical source, including forexample legumes (e.g. pea), cereals (e.g. maize, rice, wheat, oat), and tubers (e.g. potato, tapioca).

[0061] Hydrolyzed starch compounds according to the disclosure might be hydrolyzed by any suitable technique, for instance by acid treatment, heat treatment, enzymatic treatment, or a combination thereof. They can be dextrins, including maltodextrins or pyrodextrins. “Maltodextrins” classically refers to hydrolyzed starch compounds having a dextrose equivalent from 2 to 20. They are generally obtained by acid or enzymatic hydrolysis. “Pyrodextrins” are classically obtained from the action of high temperatures (generally of at least 100°C), combined with the action of an acid or alkaline or not (“British gums”), in the presence of small amounts of water. Such treatment classically leads to rebranchings and to the formation of so-called “atypical bounds” and pyrodextrins are therefore structurally different from the other hydrolyzed starches, notably from maltodextrins. Preferably, the hydrolyzed starch compounds according to the disclosure are obtained by acid hydrolysis. Preferably, the hydrolyzed starch compounds according to the disclosure are not pyrodextrins.

[0062] Hydrolyzed starch compounds have to be well differentiated from glucose, glucose syrups and cyclodextrins, the level of hydrolysis of which is too high to still be referred as “starches” as commonly understood by the person skilled in the art. In other words, glucose, glucose syrups and cyclodextrins, are not hydrolyzed starches within the meaning of the disclosure.

[0063] The functionalized starch compounds according to the disclosure being hydrolyzed, it has a reduced molecular weight, as compared to the native starch from which it is derived. Therefore, alternatively or complementarily, the hydrolyzed and functionalized starch compound according to the disclosure can be defined by its weight average molecular weight (Mw) which is preferably lower than 10 000 kDa as determined by size - exclusion chromatography (HPSEC) attached to multiangle laser - light scattering (MALLS) and refractive index (Rl) detectors. Preferably, the Mw is determined by the following method: samples of starch compounds are diluted in a mixture of dimethylsulfoxide and sodium nitrate 0.1 M. Two columns are used having a porosity of 100 and 1000 Angstrom. Elution is performed in aqueous media at a flow rate of 0.5 mL / min. The system is maintained at a temperature of 40°C. Preferably, the hydrolyzed and functionalized starch according to the disclosure has a weight average molecular weight (Mw) equal to or lower than 9 000 kDa, still preferably equal to or lower than 8 000 kDa, still preferably equal to or lower than 7 000 kDa, still preferably equal to or lower than 6 000 kDa, still preferably equal to or lower than 5 000 kDa, still preferably equal to or lower than 4 000 kDa, still preferably lower than 4 000 kDa, still preferably equal to or lower than 3 500 kDa. It is preferably equal to or higher than100 kDa, still preferably equal to or higher than 200 kDa, still preferably equal to or higher than 400 kDa, still preferably equal to or higher than 600 kDa, still preferably equal to or higher than 800 kDa, still preferably equal to or higher than 900 kDa, still preferably equal to or higher than 1 000 kDa. It is for example equal to 3 500 kDa, or equal to 1 000 kDa.

[0064] Preferably, the hydrolyzed and functionalized starch compound according to the disclosure has a viscosity in water which is preferably lower than 10 000 mPa.s at 20°C, at a shear rate of 100 s-1 , as determined on an aqueous solution comprising 10% dry weight of said starch compound, and said viscosity being determined on a rheometer with a 5 cm 1 ° cone-plate geometry. Preferably, said viscosity is equal to or lower than 5 000 mPa.s, still preferably equal to or lower than 1 000 mPa.s, still preferably equal to or lower than 500 mPa.s, still preferably equal to or lower than 100 mPa.s, still preferably equal to or lower than 50 mPa.s. It is typically higher than 1 mPa.s, preferably equal to or higher than 5 mPa.s, still preferably equal to or higher than 10 mPa.s, still preferably equal to or higher than 15 mPa.s. it is for example equal to 18 mPa.s, or equal to 42 mPa.s.

[0065] The hydrolyzed starch compound according to the disclosure is also functionalized. In other words, the starch compound according to the disclosure has functional groups added to at least one of its hydroxyl functions. Preferably, the functionalized starch compound according to the disclosure is etherified and / or esterified, still preferably etherified. It may be selected from hydroxypropyl starch, acetyl starch, hydroxyethyl starch, octenylsuccinate starch or from a mixture thereof. It is preferably hydroxypropyl starch.

[0066] In the case of hydrolyzed hydroxypropyl starch, the starch compound preferably has a content of hydroxypropyl groups between 0.5 and 10%; said percentage being expressed in dry weight of hydroxypropyl groups with respect to the total dry weight of hydrolyzed hydroxypropyl starch. The content of hydroxypropyl groups can be determined by the person skilled in the art for instance by Proton nuclear magnetic resonance (proton NMR), preferably according to a method complying with the European Pharmacopeia (“STARCH, HYDROXYPROPYL PREGELATINISED”) as in force on June 1st, 2023. It is preferably between 0.5 and 9%, still preferably between 0.5 and 8%, still preferably between 0.5 and 7%, for example equal to 7%.

[0067] Preferably, the hydrolyzed and functionalized starch compound according to the disclosure has a cold-water solubility equal to or higher than 50%, said percentage being expressed in dry weight of soluble starch with respect to the total weight of starch. Preferably, this cold-water solubility is equal to or higher than 60%, still preferably equal to or higher than 70%, still preferably equal to or higher than 80%, still preferably equal to or higher than 90%, still preferably equal to or higher than 95%. This solubility can be determined for instance by putting 5 grams of the starch compound in 200 mL distilled water,at 20°C. The dry weight dissolved can be determined after centrifugation, and desiccation of the supernatant.

[0068] Preferably, the hydrolyzed and functionalized starch compound according to the disclosure is pregelatinized. Pregelatinization classically means that the starch compound particles no longer present birefringence (lack of crystalline phase) under an optical microscope in polarized light. Pregelatinization can be commonly obtained from birefringent starch or birefringent starch compound, via a thermal treatment (50-100°C in general, notably depending on the botanical origin of the starch) in presence of water (also often referred to as “cooking”) with further drying (after the cooking and / or concomitantly).

[0069] Preferably, the hydrolyzed and functionalized starch compound according to the disclosure is derived from legume and / or cereal starch, still preferably from pea or maize starch, still preferably from pea starch, still preferably from smooth pea starch. Preferably, the pea starch has an amylose content between 20 and 50%, still preferably between 30 and 45%, still preferably between 30 and 40%, for example equal to 35%; said percentage being expressed in dry weight of amylose with respect to the total dry weight of starch. This amylose content can be determined by the person skilled in the art by way of potentiometric analysis of iodine absorbed by amylose to form a complex. Preferably, the maize starch has an amylose content greater than 5%, preferably from 10 to 40%, still preferably from 15 to 35%, still preferably from 20 to 30%, for example equal to 25%; said percentage being expressed in dry weight of amylose with respect to the total dry weight of starch.

[0070] The hydrolyzed and functionalized starch compound according to the disclosure might undergo other chemical and / or physical modification than the preferred ones exposed before, as long as it does not interfere with the desired properties, notably in term of safety and properties of the coating composition obtained thereof. However, and because it appears that it is not necessary in the present invention, the hydrolyzed and functionalized starch compound according to the disclosure is preferably no further modified.

[0071] Preferably, the hydrolyzed and functionalized starch compound according to the disclosure is a product of CAS N° 9049-76-7. Preferably, the hydrolyzed and functionalized starch compound according to the disclosure is complying with European Pharmacopeia (“STARCH, HYDROXYPROPYL PREGELATINISED”) as in force on June 1st, 2023.

[0072] Hydrolyzed and functionalized starch compound particularly useful are commercially available. Mention can be made for instance of hydrolyzed hydroxypropyl starches LYCOAT® RS 720 (CAS N°113894-92-1), or LYCOAT® RS 780 (CAS N°113894- 92-1) commercialized by the Applicant.

[0073] Preferably, the amount of polymer binders of the sugar-coating composition according to the disclosure is equal to or higher than 1.0%, preferably equal to or higher than 2.0%, preferably equal to or higher than 3.0%, preferably equal to or higher than 4%; said percentage being expressed by weight with respect to the total weight of solids of said sugar-coating composition. It is preferably equal to or lower than 10%, preferably equal to or lower than 9%, preferably equal to or lower than 8%, preferably equal to or lower than 7%, preferably equal to or lower than 6%, preferably equal to or lower than 5%, preferably equal to or lower than 4%. It is for example equal to 4%.

[0074] The sugar-coating composition according to the disclosure may be used during the sugar-coating step as such, and / or during the smoothing step. It is preferably used for the sugar-coating as such, and if a smoothing step is performed, for the smoothing as well.

[0075] The sugar-coating composition according to the disclosure might include one or more ingredient(s) other than the one mentioned before, as long as it does not interfere with the desired properties, notably in terms of safety and properties of the sugar-coating composition obtained thereof. Such other ingredients may for example be selected from:- pigments and opacifiers (e.g., titanium dioxide, calcium carbonate, lakes);- flavors, sweeteners;- active ingredients, for example pharmaceutical, nutraceutical, or veterinary active ingredients;- cellulose (e.g., cellulose, cellulose powder, microcrystalline cellulose (MCC));- or from any mixture thereof.

[0076] When TiC>2 is included, the amount of TiC>2 of the sugar-coating composition according to the disclosure is equal to or lower than 5%, preferably equal to or lower than 4%, preferably equal to or lower than 3%, preferably equal to or lower than 2%, preferably equal to or lower than 1%, preferably equal to or lower than 0.5%, preferably equal to or lower than 0.10%, preferably equal to or lower than 0.005%; said percentage being expressed by weight with respect to the total weight of solids of said sugar-coating composition.

[0077] However, preferably, the sugar-coating composition according to the disclosure does not include TiC>2 (i.e. , it is a TiCh-free sugar-coating composition).

[0078] More generally, when other ingredient(s) include opacifier(s), the total amount of opacifier(s) is preferably equal to or lower than 5%, preferably equal to or lower than 4%, preferably equal to or lower than 3%, preferably equal to or lower than 2%, preferably equal to or lower than 1%, preferably equal to or lower than 0.5%, preferably equal to or lowerthan 0.10%, preferably equal to or lower than 0.005%; said percentage being expressed by weight with respect to the total weight of solids of said sugar-coating composition.

[0079] However preferably, the other ingredient(s) do not include any opacifier.

[0080] When MCC is included, the amount of MCC of the sugar-coating composition according to the disclosure is preferably equal to or lower than 5%, preferably equal to or lower than 4%, preferably equal to or lower than 3%, preferably equal to or lower than 2%, preferably equal to or lower than 1%, preferably equal to or lower than 0.5%, preferably equal to or lower than 0.10%, preferably equal to or lower than 0.005%; said percentage being expressed by weight with respect to the total weight of solids of said sugar-coating composition.

[0081] However, preferably, the sugar-coating composition according to the disclosure does not include MCC.

[0082] When cellulose is included, the total amount of cellulose of the sugar-coating composition according to the disclosure is preferably equal to or lower than 5%, preferably equal to or lower than 4%, preferably equal to or lower than 3%, preferably equal to or lower than 2%, preferably equal to or lower than 1%, preferably equal to or lower than 0.5%, preferably equal to or lower than 0.10%, preferably equal to or lower than 0.005%; said percentage being expressed by weight with respect to the total weight of solids of said sugar-coating composition.

[0083] However, preferably, the sugar-coating composition according to the disclosure does not include any cellulose.

[0084] When pigments are included, their amount is preferably equal to or lower than 2%, preferably equal to or lower than 1%, preferably equal to or lower than 1.0, preferably equal to or lower than 0.5%, preferably equal to or lower than 0.10%, preferably equal to or lower than 0.005%; said percentage being expressed by weight with respect to the total weight of solids of said sugar-coating composition. When pigments are used, for cost reasons, they are preferably introduced at the end of the sugar-coating, or during the smoothing step. Therefore, when referring to a percentage of pigments in the sugar-coating composition, it is herein referred to a percentage of pigments with respect to the total sugar-coating composition sprayed, and not to the percentage at the moment where the pigments are added into the composition.

[0085] For the sugar-coating composition to be used, it must be in the liquid state, preferably using a polar solvent, preferably water.

[0086] Therefore, in a preferred embodiment, the sugar-coating composition according to the disclosure is a liquid composition comprising a solvent, preferably a polar solvent, preferably water.

[0087] The amount of solvent is selected so as to solubilize the crystallizable material.

[0088] In general, the solid content of the liquid coating composition, in particular when it is an aqueous coating composition, is equal to or higher than 20%, preferably equal to or higher than 30%, preferably equal to or higher than 40%, preferably equal to or higher than 50%; said percentage being expressed by weight with respect to the total weight of said sugar-coating composition. In general, the solid content of the liquid sugar-coating composition is equal to or lower than 90%, preferably equal to or lower than 80%, preferably equal to or lower than 70%. It is for example equal to 60%.

[0089] In another preferred embodiment, the sugar-coating composition according to the disclosure is a ready-to-use powdery composition. In that case, the sugar-coating composition is mixed with a solvent, preferably water, before use.

[0090] Preferably, the solid form coated with the sugar-coating composition according to the disclosure has a percentage of coating equal to or higher than 1%. This %coating, also referred to as “mass gain”, is determined as follow

[0091] [Math. 1] weight of sugar coated solid forms — weight of solid cores% coating = - - - - — — - x 100 weight of solid cores

[0092] Preferably, this %coating is equal to or higher than 2%, preferably equal to or higher than 5%, preferably equal to or higher than 10%, preferably equal to or higher than 15%, preferably equal to or higher than 20%, preferably equal to or higher than 25%. It is preferably equal to or lower than 50%, preferably equal to or lower than 45%, preferably equal to or lower than 40%, preferably equal to or lower than 35%. It is for example equal to 30%.

[0093] Preferably, the solid form coated with the sugar-coating composition according to the disclosure has a sugar-coating layer thickness equal to or higher than 50 pm, preferably equal to or higher than 100 pm, equal to or higher than 150 pm, equal to or higher than 200 pm, equal to or higher than 250 pm, equal to or higher than 300 pm. It is preferably equal to or lower than 1000 pm, preferably equal to or lower than 900 pm, preferably equal to or lower than 800 pm, preferably equal to or lower than 700 pm, preferably equal to or lower than 600 pm. It is for example from 300 pm to 500 pm.

[0094] It is understood that these %coating and coating thickness refer to the coating layer obtained by coating the solid forms with the sugar-coating composition according to the disclosure.2. Preferred sugar-coating composition comprising a crystallizable material and a stearic acid salt

[0095] The invention also covers sugar-coating compositions that performs particularly well within the context of the present invention.

[0096] The invention thus also covers a sugar-coating composition that consists of :(a) solids, said solids consisting of :(a.1) from 80.0 to 95.0% of a crystallizable material selected from sugars, sugar alcohols or any mixture thereof, preferably from 85.0 to 95.0%, preferably from 86.0 to 94.0%, preferably from 87.0 to 93.0%, preferably from 88.0 to 92.0%, preferably from 89.0 to 91.0%, for example of 90% or from 86% to 90%;(a.2) from 4.0 to 19.0% of a stearic acid salt (e.g., magnesium stearate), preferably from 4.0 to 18.0%, preferably from 4.0 to 17.0%, preferably from 4.0 to 16.0%, preferably from 4.0 to 15.0%, preferably from 4.0 to 14.0%, preferably from 4.0 to 13.0%, preferably from 4.0 to 12.0%, preferably from 4.0 to 11.0%, preferably from 4.0 to 10.0% for example 4.0% or 6.0%, or 8.0% or 10.0%;(a.3) from 1.0 to 10.0% of a polymer binder, preferably from 1.0 to 9.0%, preferably from 1.0 to 8.0%, preferably from 1.0 to 7.0%, preferably from 1.0 to 6.0%, preferably from 1.0 to 5.0%, preferably from 1.0 to 4.0%, preferably from 2.0 to 4.0%, preferably from 3.0 to 4.0%, preferably 4%;(a.4) optionally no more than 3.0% of TiC>2, preferably no more than 2.0%, preferably no more than 1.5%, preferably no more than 0.010%, preferably no more than 0.005%, preferably no TiCh;(a.5) optionally up to 1.0% of pigments, preferably up to 0.5%, preferably up to 0.10%, preferably up to 0.05%, preferably up to 0.010%, preferably up to 0.005%;(a.6) optionally no more than 3.0 % of other ingredients, preferably no more than 2.0%, preferably no more than 1.0%, preferably no more than 0.5%, preferably no more than 0.10%, preferably no more than 0.005%, still preferably no other ingredient; the sum of the percentages of from (a.1) to (a.6) being expressed by weight with respect to the total weight of solids, and their sum being equal to 100%; and,(b) optionally a solvent, preferably water.

[0097] In a preferred embodiment, the sugar-coating composition is a liquid sugar-coating composition that consists of :(a) form 40 to 80% of solids, preferably 45 to 75%, preferably 50 to 70%, preferably 55 to65%, for example 60%, said solid consisting of :(a.1) from 80.0 to 95.0% of a crystallizable material selected from sugars, sugar alcohols or any mixture thereof, preferably from 85.0 to 95.0%, preferably from 86.0 to 94.0%, preferably from 87.0 to 93.0%, preferably from 88.0 to 92.0%, preferably from 89.0 to 91.0%, for example of 90% or from 86% to 90%;(a.2) from 4.0 to 19.0% of a stearic acid salt (e.g., magnesium stearate), preferably from 4.0 to 18.0%, preferably from 4.0 to 17.0%, preferably from 4.0 to 16.0%, preferably from 4.0 to 15.0%, preferably from 4.0 to 14.0%, preferably from 4.0 to 13.0%, preferably from 4.0 to 12.0%, preferably from 4.0 to 11.0%, preferably from 4.0 to 10.0% for example 4.0% or 6.0%, or 8.0% or 10.0%;(a.3) from 1.0 to 10.0% of a polymer binder, preferably from 1.0 to 9.0%, preferably from 1.0 to 8.0%, preferably from 1.0 to 7.0%, preferably from 1.0 to 6.0%, preferably from 1.0 to 5.0%, preferably from 1.0 to 4.0%, preferably from 2.0 to 4.0%, preferably from 3.0 to 4.0%, preferably 4%;(a.4) optionally no more than 3.0% of TiC>2, preferably no more than 2.0%, preferably no more than 1.5%, preferably no more than 0.010%, preferably no more than 0.005%, preferably no TiCh;(a.5) optionally up to 1.0% of pigments, preferably up to 0.5%, preferably up to 0.10%, preferably up to 0.05%, preferably up to 0.010%, preferably up to 0.005%;(a.6) optionally no more than 3.0 % of other ingredients, preferably no more than 2.0%, preferably no more than 1.0%, preferably no more than 0.5%, preferably no more than 0.10%, preferably no more than 0.005%, still preferably no other ingredient; the sum of the percentages of from (a.1) to (a.6) being expressed by weight with respect to the total weight of solids, and their sum being equal to 100%; and,(b) from 60 to 20% of solvent, preferably from 55 to 25%, preferably from 50 to 30%, preferably from 45 to 35%, for example 40%, said solvent preferably being water; the percentages of (a) and (b) being expressed with respect to the total weight of said liquid sugar-coating composition, and their sum being equal to 100%.

[0098] Preferably, the Brookfield viscosity of said liquid sugar-coating composition is equal to or higher than 150 mPa.s, and lower than 400 mPa.s, said Brookfield viscosity being measured using a Brookfield viscometer (e.g., Viscometer DV-I+ Brookfield), using appropriate spindle, at a speed rotation of 100 rpm, for example according to the method given in Example Section 4. Preferably, said Brookfield viscosity is from 150 to 300 mPa.s, preferably from 150 to 300 mPa.s, preferably from 200 to 300 mPa.s, preferably from 200 to 250 mPa.s, or of about 250 mPa.s.

[0099] In another preferred embodiment, the sugar-coating composition is a powdery sugar-coating composition that consists of:(a.1) from 80.0 to 95.0% of a crystallizable material selected from sugars, sugar alcohols or any mixture thereof, preferably from 85.0 to 95.0%, preferably from 86.0 to 94.0%, preferably from 87.0 to 93.0%, preferably from 88.0 to 92.0%, preferably from 89.0 to 91.0%, for example of 90% or from 86% to 90%;(a.2) from 4.0 to 19.0% of a stearic acid salt (e.g., magnesium stearate), preferably from 4.0 to 18.0%, preferably from 4.0 to 17.0%, preferably from 4.0 to 16.0%, preferably from 4.0 to 15.0%, preferably from 4.0 to 14.0%, preferably from 4.0 to 13.0%, preferably from 4.0 to 12.0%, preferably from 4.0 to 11.0%, preferably from 4.0 to 10.0% for example 4.0% or 6.0%, or 8.0% or 10.0%;(a.3) from 1.0 to 10.0% of a polymer binder, preferably from 1.0 to 9.0%, preferably from 1.0 to 8.0%, preferably from 1.0 to 7.0%, preferably from 1.0 to 6.0%, preferably from 1.0 to 5.0%, preferably from 1.0 to 4.0%, preferably from 2.0 to 4.0%, preferably from 3.0 to 4.0%, preferably 4%;(a.4) optionally no more than 3.0% of TiC>2, preferably no more than 2.0%, preferably no more than 1.5%, preferably no more than 0.010%, preferably no more than 0.005%, preferably no TiCh;(a.5) optionally up to 1.0% of pigments, preferably up to 0.5%, preferably up to 0.10%, preferably up to 0.05%, preferably up to 0.010%, preferably up to 0.005%;(a.6) optionally no more than 3.0 % of other ingredients, preferably no more than 2.0%, preferably no more than 1.0%, preferably no more than 0.5%, preferably no more than 0.10%, preferably no more than 0.005%, still preferably no other ingredient; said percentages being expressed by weight with respect to the total weight of said powdery sugar-coating composition, and their sum being equal to 100%.

[0100] Preferably, the nature of ingredients used is as described before.3. Suqar-coatinq process, and solid forms obtained therefrom

[0101] The instant disclosure also relates to a sugar-coating process, in particular for obtaining the solid form coated with the sugar-coating composition according to the disclosure, comprising coating solid cores with a sugar-coating composition according to the disclosure i.e., a sugar-coating composition comprising a crystallizable material and a stearic acid salt (e.g., magnesium stearate).

[0102] Preferably, said sugar-coating composition is as described above in sections 1. or 2.

[0103] The sugar-coating composition according to the disclosure may be used during the sugar-coating step as such, and / or smoothing step. It is preferably used at least during the sugar-coating as such.

[0104] Therefore, the process according to the disclosure preferably comprises or consists of:(1) an optional step of film-coating the solid cores,(2) a step of sugar-coating the solid cores with a sugar-coating composition according to the disclosure,(3) an optional step of smoothing the solid cores, preferably performed right after step (2),(4) an optional step of polishing performed after step (2) or after step (3) if the latter is carried out,(5) an optional step of printing, performed after step (2), or after step (3) if the latter is carried out, or after step (4) if the latter is carried out,(6) a final step of collecting the sugar-coated solid forms thus obtained.

[0105] Coloring may be performed during step (2) of sugar-coating or during step (3) of smoothing, by adding at least one pigment in the composition. When it is performed during step (2) of sugar-coating, for cost reasons, the pigment is preferably added during the last phase of said sugar-coating step (2).

[0106] Preferably, sugar-coating step (2) comprises:- a step (2. a) of spraying said sugar-coating composition onto a moving bed of solid cores, said cores being placed into a chamber equipped with a perforated rotary drum, said spraying being performed by means of compressed air nozzles;- at least one step (2.b), concomitant with step (2. a), of drying the coating composition sprayed.

[0107] The process according to the disclosure might further include a step of preparing a sugar-coating composition according to the disclosure, preferably by blending a powdery sugar-coating composition according to the disclosure with any suitable solvent, preferably water.

[0108] Preferably, the solid content of the liquid coating composition thus obtained, is equal to or higher than 20%, preferably equal to or higher than 30%, preferably equal to or higher than 40%, preferably equal to or higher than 50%; said percentage being expressed by weight with respect to the total weight of said sugar-coating composition. In general, the solid content of the liquid sugar-coating composition is equal to or lower than 90%, preferably equal to or lower than 80%, preferably equal to or lower than 70%. It is for example equal to 60%.

[0109] Preferably, the Brookfield viscosity of the liquid coating composition according to the disclosure equal to or higher than 150 mPa.s, and lower than 400 mPa.s, said Brookfield viscosity being measured using a Brookfield viscometer (e.g., Viscometer DV-I+ Brookfield), using appropriate spindle, at a speed rotation of 100 rpm, for example according to the method given in Example Section 4. Preferably, said Brookfield viscosity is from 150 to 300 mPa.s, preferably from 150 to 300 mPa.s, preferably from 200 to 300 mPa.s, preferably from 200 to 250 mPa.s, or of about 250 mPa.s.

[0110] Preferably, during the coating, the coating composition is under high-speed agitation. The speed will depend on the volume of the coating composition and of the shape and size of the propeller.

[0111] In a preferred embodiment, the sugar-coating step (2) according to the disclosure uses a single sugar-coating composition i.e. , the sugar-coating composition has a constant formulation throughout the duration of step (2), except that pigments might be added, in particular during the last phase of the sugar-coating step (2). In a preferred embodiment, when a smoothing step (3) is performed, the sugar-coating composition used for steps (2) and (3) are the same, except that pigments might be added, in particular during the last phase of the sugar-coating step (2) and / or during step (3).

[0112] The temperature of the solvent is typically chosen such that the crystallizable material is well solubilized in the sugar-coating composition to be sprayed. This temperature thus depends on the nature and amount of crystallizable substance(s) present in the composition. In the process according to the disclosure, this temperature is typically selected from 20 to 90°C. It is preferably lower than 90°C, preferably equal to or lower than 80°C, preferably equal to or lower than 70°C, preferably equal to or lower than 60°C, preferably equal to or lower than 50°C, preferably equal to or lower than 40°C, preferably equal to or lower than 30°C. It is preferably equal to or higher than 10°C, preferably equal to or higher than 15°C, preferably equal to or higher than 20°C. it is preferably used at room temperature, which is typically from 20°C to 25°C.

[0113] Preferably, the temperature of the sugar-coating composition is typically selected from 1 to 90°C. It is preferably lower than 90°C, preferably equal to or lower than 80°C, preferably equal to or lower than 70°C, preferably equal to or lower than 60°C, preferably equal to or lower than 50°C, preferably equal to or lower than 40°C, preferably equal to or lower than 30°C, preferably equal to or lower than 25°C.

[0114] When xylitol is used as the crystallizable material, the temperature of the solvent used is preferably as described before. However, the temperature of the coating composition itself will generally be lower, due to the high dissolution enthalpy of xylitol.Therefore, for example, for a sugar-coating composition using water at 20°C as solvent, the sugar-coating composition will generally have a temperature of 5 to 10°C after the xylitol is solubilized, and from 15 to 20°C during the sugar-coating step (2).

[0115] For the spraying of the coating composition, the number of compressed air nozzles used is conventionally chosen as a function of the dimensions of the sugar-coating chamber, according to the constructor's recommendations. This number of nozzles is typically from 1 to 2 nozzle(s) per section that is 40 cm in diameter of the sugar-coating chamber. This number of nozzles ranges, for example, from 1 to 10, for example from 1 to 6. Preferably, the process according to the disclosure doesn’t use nozzles other than compressed air nozzles for spraying the coating composition.

[0116] Preferably, the nozzles used have an orifice which has a diameter selected from 0.1 to 2.8 mm, preferably from 0.1 to 2.5 mm, preferably from 0.1 to 2.2 mm, for example from 0.3 to 2.0 mm, or from 0.5 to 1.8 mm or from 0.5 to 1 .5 mm, or from 0.5 to 1.2 mm, or from 0.5 to 1.0 mm.

[0117] Preferably, the spray rate is increased during the sugar-coating step (2). Indeed, the use of lower flow rates in the beginning of the coating process favors the first phase of crystallization that occurs at the surface of the solid cores. The flow rate can then be increased to decrease the coating time. Preferably, the spray rates are selected from 1 to 20 g / min / kg of solid cores, preferably from 1 to 15 g / min / kg of solid cores, preferably from 2 to 15 g / min / kg of solid cores, preferably from 2 to 10 g / min / kg of solid cores.

[0118] For the drying step (2.b), the inlet temperature is preferably lower than 100°C, preferably equal to or lower than 80°C, preferably equal to or lower than 70°C, preferably equal to or lower than 60°C, preferably equal to or lower than 50°C. It is preferably equal to or higher than 20°C, preferably equal to or higher than 30°C, preferably equal to or higher than 40°C. It is for example equal to 45°C.

[0119] For the drying step (2.b), the air flow generally depends on the size of the coating chamber. It may be selected from 50 to 8000 m3 / h, for example from 100 to 7000 m3 / h, for example from 100 to 1000 m3 / h per 5 kg of solid cores. It is for example equal to 500 m3 / h per 5 kg of solid cores.

[0120] The exit of the drying air is preferably performed by suctioning the air from the chamber through perforations of the rotary drum.

[0121] Preferably, the temperature of the bed of solid cores undergoing sugar-coating step (2) is equal to or lower than 70°C, preferably equal to or lower than 60°C, preferably equal to or lower than 50°C, preferably equal to or lower than 40°C. It is preferably equal toor higher than 10°C, preferably equal to or higher than 20°C, preferably equal to or higher than 30°C. it is for example from 30°C to 40°C.

[0122] Preferably, before the start of the sugar-coating step (2) i.e., before the spraying begins, the process according to the disclosure comprises a step of heating the bed of solid cores to be sugar-coated. The purpose is to bring the bed temperature to a target value that is the temperature of the solid cores during sugar-coating.

[0123] To set the bed of solid cores in motion, the rotation speed of the drum is selected according to the dimensions of the chamber, and according to the size of the solid cores to be coated. It is in general selected from 3 to 30 rpm (rotation per minute), preferably from 5 to 20 rpm, preferably from 5 to 15 rpm. It is for example equal to 8 rpm when using a rotary drum with a diameter of 48.26 cm.

[0124] The sugar-coating step (2) preferably concomitantly carries out spraying and drying of the coating composition.

[0125] However, it is possible to envision introducing steps of distribution (“pause time”) and spraying in the absence of drying, as long as this does not interfere with the desired properties, in particular with regard to the quality of the sugar-coated solid forms obtained and / or the ease of managing the process.

[0126] Preferably, sugar-coating step (2) phases during which the spraying is not carried out concomitantly with the drying represent less than 50% of the sugar-coating process time, preferably less than 40%, preferably less than 30%, preferably less than 20%, preferably less than 10%, preferably less than 5%. Still preferably, the sugar-coating step (2) does not comprise a spraying phase in the absence of drying.

[0127] Preferably, the optional pause times (times between two spraying phases during which there is neither a spraying nor drying) represent less than 50% of the sugar-coating step (2) time, preferably less than 40%, preferably less than 30%, preferably less than 20%, preferably less than 10%, preferably less than 5%. Still preferably, the sugar-coating step (2) does not comprise any pause time.

[0128] Preferably, the mass gain during the sugar-coating step (2) process is equal to or higher than 0.1% per minute, preferably equal to or higher than 0.2% per minute. It is in general equal to or lower than 1 .0% per minute, even equal to or lower than 0.9% per minute, even equal to or lower than 0.8% per minute, even equal to or lower than 0.7% per minute, even equal to or lower than 0.6% per minute. It is for example equal to 0.3% per minute.

[0129] The sugar-coating process according to the disclosure may also comprise usual steps other than sugar-coating step (2), as long as it does not interfere with the desiredproperties, in particular with regard to the quality of the sugar-coated solid forms obtained and / or the ease of managing the process, e.g.: a step (1) of film-coating, a step (3) of smoothing, a step (4) of polishing, a step (5) of printing.

[0130] Advantageously, if steps (1), (3), and / or (4) are carried out, they are performed in the same equipment as that used for the sugar-coating step (2).

[0131] Preferably, in particular because it is not needed thanks to the addition of a stearic acid salt, the process according to the disclosure does not include a smoothing step (3).

[0132] The equipment used to carry out the sugar-coating process according to the disclosure typically comprises a unit for storing the sugar-coating composition, comprising at least one outlet for transporting (for example by way of a peristaltic pump) the sugar- coating liquid to a device for spraying the sugar-coating liquid. The sugar-coating liquid is applied by means of a spraying device onto a bed of solid cores contained in the chamber, said chamber being equipped with a rotating drum for setting the bed of solid cores in motion. The drum is preferably a perforated rotating drum, and the spraying device preferably a compressed air nozzle. The equipment also comprises an air inlet at the level of the chamber of the drum, for the drying of the sugar-coating liquid. The drying air preferably exits by means of the perforations of the rotating drum, by suctioning of the air from the chamber.

[0133] Preferably, the perforated wall zone of the rotating drum according to the disclosure represents at least 50% of the curved surface of said drum wall, preferably at least 60%, preferably at least 70%, preferably at least 80%, preferably at least 90%. Most preferentially, the drum wall is perforated over its entire curved surface.

[0134] Preferably, in particular for reasons of simplicity, and / or of amount of space taken up, and because the process of the invention allows it, the step of setting the bed of solid cores in motion excludes transporting said solid cores in a longitudinal axis. This means in particular that the solid cores undergoing sugar-coating step (2) are not transported from one chamber to another i.e., that they are sugar-coated in a single chamber, and / or that the bed of solid cores is not sugar-coated in a longitudinal chamber along which they are transported.

[0135] The instant disclosure also covers a solid form obtained or obtainable by the sugar- coating process according to the disclosure.4. Use of a stearic acid salt for improving the surface of a sugar-coating layer of a sugar-coated solid form

[0136] The disclosure also relates to the use of a stearic acid salt (e.g., magnesium stearate) in the sugar-coating layer of a sugar-coated solid form, for improving the surface of said sugar-coating layer.

[0137] Preferably, the use comprises carrying out a sugar-coating process according to the disclosure. Preferably, the sugar-coated solid forms are as described before. Preferably, the stearic acid salt (e.g., magnesium stearate) is as described before.

[0138] The term “improving the surface” means that the coating layer obtained by coating with a sugar-coating composition comprising a stearic acid salt has improved surface as compared to a coating layer obtained with same sugar-coating composition without said stearic acid salt. The term “improving the surface” can for example mean improving the color, increasing the brightness, increasing the opacity or increasing the smoothness (or decreasing the roughness or rugosity) of the coating layer. Preferably, the method according to the disclosure is for increasing the smoothness (or decreasing the roughness or rugosity) of the coating layer. This smoothness, roughness or rugosity may be determined by the person skilled in the art by measuring the arithmetic average height (Sa), in pm, for example using VHX-7000 microscope (KEYENCE). The Sa value is the extension of the Ra parameter (arithmetic mean height of a line) to a surface. It gives the arithmetic mean, in absolute value, of the difference in height of each point with respect to the mean plane of the surface. A 3D reconstruction is realized, then a rugosity measure is done in according to parameters following parameters: Gaussian filter; S-Filter: 8 pm; L-Filter: 0.8 pm. Surface roughness is an average of 5 values.

[0139] The instant disclosure also relates to a method for improving the surface of a sugar- coating layer of a sugar-coated solid form, comprising including a stearic acid salt (e.g., magnesium stearate) in said coating layer.

[0140] Preferably, the method comprises carrying out a sugar-coating process according to the disclosure. Preferably, the sugar-coated solid forms are as described before. Preferably, the stearic acid salt (e.g., magnesium stearate) is as described before.

[0141] In the instant disclosure, the amounts of ingredients are generally expressed in percentages by weight. Unless otherwise specified these weights are amounts of ingredients as such, in their powdery or oily form. Powdery ingredients may include small amount of water (also referred to as %moisture or as “loss on drying”) and / or small amounts of impurities.

[0142] On the contrary, if the amounts are expressed in “dry weights”, this refers to amounts of anhydrous ingredients.

[0143] Other characteristics and advantages of the present invention will emerge clearly on reading the examples given hereinafter, which illustrate the invention without however limiting it.Examples1. Sugar-coating compositions to be tested

[0144] The materials used in the sugar-coating compositions were the following- Xylitol (XYLISORB® 300, ROQUETTE)- Polymer binder: Hydroxypropylated hydrolyzed pea starch, having a cold-water solubility higher than 95% (LYCOAT® RS720, ROQUETTE)- Titanium dioxide (TiO2)- Magnesium stearate having low specific area: Magnesium stearate LS (ROQUETTE) with a specific surface area of 4.5 m2 / g- Magnesium stearate (MgSt) having medium specific area: Magnesium stearate STD (ROQUETTE) with a specific surface area of 8 m2 / g- Magnesium stearate having high specific area: Magnesium stearate HS (ROQUETTE) with a specific surface area of 22 m2 / g

[0145] The formulations of the sugar-coating compositions tested are presented in Table 1.

[0146] [Table 1];0147] The liquid sugar-coating compositions were prepared at 60 wt.% of solids.2. Sugar-coating process

[0148] Solid forms were coated with these sugar-coating formulations according to the coating process parameters described herein.

[0149] The equipment and parameters used for all trials were the followings:- Type of pan coating: RAMA COTA FC19- Pan diameter: 19”- Solid cores to be coated: 5kg of solid cores- Number of spray nozzle: 1- Type of spray nozzle: Schlick 970 / 7-1 S75- Orifice diameter: 0.8 mm- peristaltic pump: Watson Marlow model 323, Head 313 DW (3 rollers)- Number of baffles: 6- Exacanal tube (diameter in: 4 mm, diameter out 8 mm)- Control air pressure: 4 bars- Atomizing pressure: 1.2 bar- Pattern air pressure: 1.2 bar- Drying air flow: 500 m3 / h- Pan differential pressure: below 0- Pan rotation speed: 8 rpm- Inlet air temperature: 45°C- %coating: 30%

[0150] The solid cores were tablets that consisted of 74% mannitol (PEARLITOL® 200 SD, ROQUETTE), 25% microcrystalline cellulose (MICROCEL® MC 102, ROQUETTE), 1% magnesium stearate (magnesium stearate STD, ROQUETTE); said percentage being expressed by weight with respect to the total weight of tablet. The tablets were prepared on FETTE P1000 press so as to obtain 10 mm concave tablets having a weight of 400 mg, and a hardness of 185 N.

[0151] The process parameters specific to each trial are presented in Table 2.

[0152] [Table 2]3. Evaluation of the sugar-coated solid forms

[0153] The sugar-coated formulation thus obtained were evaluated for their smoothness, by measuring the arithmetic average height (Sa), in pm, using VHX-7000 microscope (KEYENCE), with the method described before in the Description section.

[0154] For comparison, the following commercially available sugar-coated solid forms were also evaluated: ADVIL® (GlaxoSmithKline), Ibuprofen (CVS Health), MENTOS® (Perfetti Van Melle).

[0155] Results are presented on Figure 1.

[0156] When comparing Composition #1 to Compositions #2 and #3, it can be observed that the addition of magnesium stearate allows decreasing the rugosity of the hard-coating tablets comprising TiO2. Same observation can be made for TiO2-free formulations, when comparing formulation #4 to formulations #5-10. By comparing Formulation #6 to Formulations #9 and #10, it can be observed that magnesium stearate having average specific surface area performs better than magnesium stearate having low or high specific surface area. Finally, we observe that increasing the amount of magnesium stearate increases the smoothness of the coating. Best results were obtained when the amount of magnesium stearate was greater than 4%, for example from 6 to 10%.

[0157] The coating thickness was also evaluated by Scanning Electron Microscopy (SEM) (FEI QUANTA 200F, TERMOFISHER) on samples #1, #6 and #7. Results are presented on Figure 2.

[0158] Stability of tablets coated with formulation #6 was evaluated by putting the coating tablets into the oven at 45°C for 9 weeks. Then, color measurements were performed on 10 coated tablets with our KONICA MINOLTA CM-5 with the following settings: Standardilluminant: D65; Viewing angle: 10°; Aperture disc: 3mm; SCI mode (Specular Component Included measurement mode is used to evaluate color of an object, independent of its surface condition); UV = 100%; Cl ELAB color space (L*a*b* CIE 1976); Whiteness index: Wl (E313-96) : scale -100 until 100.

[0159] The lightness L* takes values between 0 (black) and 100 (reference white). The parameter a* represents the value on a green red axis. The parameter b* represents the value on a blue —» yellow axis.

[0160] The results are shown in Table 3.

[0161] [Table 3]

[0162] The color difference was of AE = 0.4, while a visible color difference should be higher than 1.5. These results thus demonstrate the stability of the coating formulation according to the disclosure, that did not show any discoloration or color change after 9 weeks at 45°C.4. Sugar-coating formula improvement

[0163] The inventors then found out that the formulation still needed to be improved, because of a lack of stability of the liquid coating formulation during the coating process. Indeed, it was observed that magnesium stearate tended to rise to the surface (“creaming” phenomenon), as a result of its low density.

[0164] One hypothesis was that modifying the viscosity could positively impact the formulation stability. Various formulations including different polymer binders in different amounts were thus tested for their viscosity, processability and turbidity. The polymer binders tested had the features as shown in Table 4.

[0165] [Table 4]

[0166] The formulations of the sugar-coating compositions tested were as shown in Table5.

[0167] [T able 5] - Coating formulations testedRT: Room Temperature (25°C)

[0168] Powders were mixed manually and then introduced into the water (60% or 70% solids) at room temperature or at 70°C. The purpose of the trials performed at a higher solid content of 70% was to ease the coating drying by reducing the amount of water to evaporate. Consequently, the solution temperature was increased to 70°C to allow complete solubilization of xylitol.

[0169] The blend was then dispersed during one hour at 25°C using high-speed agitator (IKA agitator) at 600 rpm. the ease of dispersion and the presence or not of a foaming phenomenon were noted. Then, the blend was mixed under magnetic stirring (600 rpm) during one hour at 25°C. The evolution of the suspension and the presence of a creaming phenomenon were observed.

[0170] Brookfield viscosity was measured using Viscometer DV-I+ Brookfield, using Spindle 2 or 3 depending on the formulation, at a speed rotation of 100 rpm, after 1 hour agitation.

[0171] The solution aspect after high-speed agitation was homogenous for all formulations. The solution aspect after magnetic stirring was homogenous for all formulations.

[0172] The viscosity results are presented in Figure 3.

[0173] The more viscous formulation (comprising 6 wt.% hydroxypropylated hydrolyzed starch, and prepared at 60% solids, RT) was used for a coating trial but the coating was not possible due to its too high viscosity.

[0174] CLEARGUM® CO 01 performed better than CLEARGUM® CO 03, as the latter did not provide enough viscosity to the formulation, The polymer binder that had the best impact on viscosity was LYCOAT® RS720.

[0175] Then, the formulations were analyzed using TURBISCAN™ to observed whether phase shifting occurred.

[0176] Whatever the polymer binder used, the suspension appears relatively easy to make. The one-hour mixing was mainly dictated by the initial temperature drop. No foaming occurred. The stirring was stopped, and the creaming speed was measured using TURBISCAN™ equipment, according to the manufacturer’s recommendation. Results are presented in Figure 4.

[0177] It was observed that the creaming speed decreased while the viscosity increased.

[0178] A coating trial was then performed as described in Example section 2, using a coating formulation whose solids consisted of 90 wt.% xylitol, 6 wt.% magnesium stearate STD, 4 wt. % LYCOAT® RS720. The suspension was prepared using a high stirring (I KA for 60 minutes, then the suspension was stirred with a magnetic stirrer during all the coating. When the suspension level decrease in the beaker, some magnesium stearate sticks to the surface of the beaker and creates a type of collar. This phenomenon did not occur when using high-speed agitator (I KA agitator) at 1000 rpm. The quantity of magnesium stearate at the surface of the beaker remained negligeable. The phenomenon was more important with the tested octenyl succinate starch than with the tested hydroxypropylated starch. It thus preferable to use high-speed agitation during the coating.

[0179] Furthermore, the coated tablets obtained were not friable at all.

[0180] The use of the starch having the highest viscosity (Hydroxypropylated hydrolyzed pea starch) at a concentration of 4 %, as weight with respect to the total weight of solids, was the best formulation of all the formulations tested. The coating formulations obtained thereof are stable in both tested conditions (60% solids, RT and 70% solids, 70°C), and are easy to handle.

Claims

Claims

1. A solid form coated with a sugar-coating composition, said sugar-coating composition comprising a crystallizable material and a stearic acid salt, said crystallizable material being selected from sugars, sugar alcohols, or from any mixture thereof.

2. The solid form of claim 1 , wherein said stearic acid salt is an alkali or alkaline- earth metal salt of stearic acid, or a mixture thereof.

3. The solid form of any of claim 1 or 2, wherein said stearic acid salt is selected from magnesium stearate, calcium stearate, sodium stearate or from any mixture thereof, preferably from magnesium stearate, calcium stearate, or from any mixture thereof.

4. The solid form of claim 3, wherein said stearic acid salt is magnesium stearate.

5. The solid form of any of claims 1 to 4, wherein said sugar-coating composition further include a polymer binder.

6. A sugar-coating composition that consists of:(a) solids, said solids consisting of:(a.1) from 80.0 to 95.0% of a crystallizable material selected from sugars, sugar alcohols or any mixture thereof, preferably from 85.0 to 95.0%, preferably from 86.0 to 94.0%, preferably from 87.0 to 93.0%, preferably from 88.0 to 92.0%, preferably from 89.0 to 91.0%, for example from 85 to 90%, or from 86 to 90%, or of 90%;(a.2) from 4.0 to 19.0% of a stearic acid salt, preferably from 4.0 to 18.0%, preferably from 4.0 to 17.0%, preferably from 4.0 to 16.0%, preferably from 4.0 to 15.0%, preferably from 4.0 to 14.0%, preferably from 4.0 to 13.0%, preferably from 4.0 to 12.0%, preferably from 4.0 to 11.0%, preferably from 4.0 to 10.0% for example 4.0% or 6.0%, or 8.0% or 10.0%;(a.3) from 1.0 to 10.0% of a polymer binder, preferably from 1.0 to 9.0%, preferably from 1.0 to 8.0%, preferably from 1.0 to 7.0%, preferably from 1.0 to 6.0%, preferably from 1.0 to 5.0%, preferably from 1.0 to 4.0%, preferably from 2.0 to 4.0%, preferably from 3.0 to 4.0%, preferably 4%;(a.4) optionally no more than 3.0% of TiC>2, preferably no more than 2.0%, preferably no more than 1.5%, preferably no more than 0.010%, preferably no more than 0.005%, preferably no TiCh;(a.5) optionally up to 1.0% of pigments, preferably up to 0.5%, preferably up to 0.10%, preferably up to 0.05%, preferably up to 0.010%, preferably up to 0.005%;(a.6) optionally no more than 3.0 % of other ingredients, preferably no more than 2.0%, preferably no more than 1.0%, preferably no more than 0.5%, preferably no more than 0.10%, preferably no more than 0.005%, still preferably no other ingredient;the sum of the percentages of from (a.1) to (a.6) being expressed by weight with respect to the total weight of solids, and their sum being equal to 100%; and,(b) optionally a solvent, preferably water.

7. The sugar-coating composition of claim 6, wherein said stearic acid salt is an alkali or alkaline-earth metal salt of stearic acid, or a mixture thereof.

8. The sugar-coating composition of claim 7, wherein said stearic acid salt is selected from magnesium stearate, calcium stearate, sodium stearate or from any mixture thereof, preferably from magnesium stearate, calcium stearate, or from any mixture thereof.

9. The sugar-coating composition of claim 8, wherein said stearic acid salt is magnesium stearate.

10. A sugar-coating process comprising coating solid cores with a sugar-coating composition as defined in any of claims 1 to 9.

11. Use of a stearic acid salt in the sugar-coating layer of a sugar-coated solid form, for improving the surface of said sugar-coating layer.

12. The use of claim 11 , for improving the color, and / or increasing the brightness, and / or increasing the opacity, and / or increasing the smoothness, and / or decreasing the roughness and / or decreasing the rugosity of said sugar-coating layer.

13. The use of any of claims 11 or 12, for increasing the smoothness, and / or decreasing the roughness and / or decreasing the rugosity of said sugar-coating layer.

14. A sugar-coated solid form obtainable by the process of claim 10.

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