RU2796924C2 - New method for pelleting and irregular shape solid pelleted forms - Google Patents

Abstract

FIELD: formation of coated moulds.

SUBSTANCE: proposed coating method for preparing a solid coated form includes the step of spraying a coating liquid containing a composition of crystallizing substances, including at least one substance selected from sugars and polyhydric alcohols, onto a layer of cores in motion. Moreover, said cores are placed in a chamber equipped with a rotating perforated drum, and said spraying is provided by at least one nozzle using compressed air. At least one step of drying said sprayed coating liquid is carried out simultaneously with the spraying step. The coated solids thus obtained are then collected. The hard coated form is selected from tablets, hard gelatine capsules, soft capsules, granules, microspheres, grains, seeds, biscuits, breakfast cereals, confectionery and products in the form of powder and/or crystals.

EFFECT: invention makes it possible to preserve relief imprints present on the surface of coated forms, such as brand names, names of active molecules or dosages of active substances.

6 cl, 15 dwg

Description

The subject of the present invention are new irregularly shaped solid pans and a panning process particularly useful in their manufacture.

Prerequisites for the creation of the invention

Coating (“sugar coating” - “sugar coating”) is an operation that is used in particular in the manufacture of confectionery or pharmaceuticals, and consists in creating a more or less hard crystallized coating (“hard” or “soft coating” - “ hard" or "soft coating") on the surface of solid or powdered products to protect them for many reasons or to make them attractive in appearance or taste.

Coating with a shell of a solid form (kernel) is carried out in a container rotating around its axis and called a drageeing drum, inside which there are many cores that form a mass in motion, over the surface of which the material constituting the future shell is distributed in a liquid state (“liquid or syrup for sugar coating). By applying this liquid and evaporating the water introduced by this liquid, a hard and crystalline coating is obtained.

A sugar coating syrup generally consists of one or more crystallizing agents and also traditionally contains binders such as gum arabic or gelatin, coloring agents, opacifiers such as TiO ₂ , mineral fillers such as talc, silica, calcium carbonate, intense sweeteners, flavors, vitamins, active ingredients.

Coating is a relatively time-consuming process that includes a large number of successive stages. Each of these steps, also referred to as "panning cycles", generally includes a coating phase, usually by spraying the panned syrup onto the kernels, a rotational distribution phase of said syrup on the kernels, also referred to as a pause period, and a drying phase of each new layer of syrup, performed by blowing hot and dry air.

Coating makes it possible to obtain solid forms having a very attractive appearance, but lacks the flexibility in terms of its implementation and the visual aspects that can be obtained. More specifically, and this is the subject of the present invention, it is not possible to obtain solid forms having complex irregular shapes, for example, those having embossed impressions or sharp ribs, by panning. Indeed, when solid forms with such irregularities are coated, these latter disappear after coating: the coating liquid fills the grooves and cavities formed by relief prints (“logo in-filling” - “filling in the brand name form”), and thickens the sharp ribs that while smoothing out. Thus, it is also not possible to maintain the asymmetry that the nuclei have in certain cases, such as when these nuclei are grains. Thus, solid forms obtained by drageeing traditionally have a rough and rounded configuration, to a small extent repeating that of the original cores.

Therefore, for example, in the pharmaceutical industry, as a rule, it is preferred to cover the tablets with a film (“film coating” - “applying a film coating on tablets”). In this method, not a syrup is applied, but a film-forming composition, usually based on cellulose derivatives such as hydroxypropyl methylcellulose (HPMC) or, more recently, modified starches. This film-forming composition forms a thin film on the surface of the tablets and makes it possible to successfully preserve the relief imprints present on the surface of the tablets, such as brand names, names of active molecules or dosages of active substances.

Although this method allows accurate shapes to be maintained, it results in tablets having a much less attractive appearance than coated forms. In addition, during film deposition, an amorphous coating is formed, which is less stable than the crystallized coating obtained as a result of panning.

Thus, at the present time, there is no method that allows the production of pelleted solid forms with a peculiar shape. Therefore, when a manufacturer wishes to display brand names or other designs on the surface of the solid coated plates, he does so by applying the colored composition to the surface of the coated plates.

An approach to this problem is described in US 2008/0026131 A1. This document discloses a drageeing method for maintaining the irregular shape of chocolates. However, this method only preserves rough and rounded shapes in general, not complex irregular shapes. The idea of the document US 2008/0026131 A1 does not allow the production of solid coated forms having irregular complex shapes, such as ribs or embossed prints. This method, which is particularly time-consuming and labor-intensive, involves many panning cycles (syrup application / spreading / drying).

Objectives of the invention

Thus, it is an object of the present invention to provide hard coated forms having a complex irregular shape, as well as a method to achieve this goal.

It is also an object of the present invention to provide a particularly simple and flexible process for panning solid forms.

Presentation of the invention

The Applicant has been able to produce solid panned forms in which irregular shapes, such as embossed prints, sharp ribs, and asymmetric shapes, are retained after panning.

The Applicant has succeeded in achieving this by developing a new coating process, characterized in that it includes:

- step (a) spraying a coating liquid containing a composition of crystallizing substances onto a layer of nuclei in motion, wherein said nuclei are placed in a chamber equipped with a rotating perforated drum, and said spraying is provided by at least one nozzle for supplying compressed air (one pneumatic nozzle) ;

- at least one step (b) drying said sprayed coating liquid, performed simultaneously with step (a);

step (c) collecting the coated solids thus obtained.

The method according to the invention is applicable to various solid forms (tablets, chewing gum, etc.) and creates great opportunities for manufacturers, more specifically the possibility from now on to offer the consumer a new appearance of hard coated forms.

In this method, drying and spraying are carried out simultaneously. Meanwhile, in a surprising way, despite the constant moistening of the nuclei, they are not washed out, and irregular shapes are preserved.

This is particularly surprising since until now it has been thought that the spraying must necessarily be stopped for an appreciable period of time during the process: otherwise the kernels will be constantly moistened, as a result of which the substance used for the coating will not be able to crystallize, the solid form will be washed out and destroyed, and nuclei stick to each other (sticking phenomenon). Meanwhile, in the context of the method according to the invention, this phenomenon was not observed even on very hygroscopic cores, that is, cores that greedily absorb water.

Also, and in contrast to conventional panning, the process of the invention does not require an increased solids content in the panning liquid (at least 70% for traditional panning with maltitol). This is equally contrary to the general knowledge in this area for the same reasons that were stated in the previous paragraph (significant wetting of the nuclei).

The ability to use liquid with a low solids content provides a number of advantages. Firstly, this allows the use of coating liquids at low temperatures and, consequently, the introduction of heat-labile ingredients into these liquids or into core compositions intended for coating. Indeed, if traditionally high temperatures are used in panning, this is done in order to ensure a high content of crystallizing substances in the panning solution in dissolved form. Since such a high solids content is not necessary in the process of the invention, the temperature of the coating liquid can be reduced.

Secondly, it also allows panning with crystallizable substances having poor water solubility. A good illustration of this advantage is provided in the examples in point 1 (tests "Man-IN1 to -IN5") or with mannitol, which was used for panning. This panning does not require the addition of large amounts of binders, unlike prior art methods. In other words, here we are talking about drageeing, since crystallizing substances are a significantly predominant component.

Thus, for the first time, the process according to the invention makes it possible to obtain solid coated forms in which the coated layer contains a large amount of mannitol, and this without the need to add excessive amounts of binders, such as gum arabic or polyvinyl alcohol. The Man-IN5 test even shows that binders can be dispensed with altogether.

In addition, the method developed by the Applicant has other advantages which make it also useful for panning solid forms that do not have particularly complex irregular shapes. More specifically, the method of the invention is much more flexible than conventional panning methods and can be very easy to implement.

Moreover, this method is applicable to various crystallizable substances, as shown in point 1 below in the examples. More specifically, sucrose, xylitol, erythritol and mannitol give very satisfactory results.

Finally, the method according to the invention does not necessarily require a major change in its parameters during implementation (drying temperature, composition of the coating liquid, etc.) and can be carried out in relatively simple and small-sized equipment.

None of the prior art documents disclose or suggest such a method. For example, the above document US 2008/0026131 A1 in no way implements drying and spraying at the same time.

Brief summary of the invention

The first object of the present invention is a solid coated form having at least one embossed imprint and/or at least one rib and/or something that defines its asymmetry, wherein the coating layer of said solid coated asymmetric shape exactly follows the shape of the core, from which it was received.

The subject of the present invention is also a process particularly useful for making hard coated molds having complex irregular shapes, comprising:

- step (a) spraying a coating liquid containing a composition of crystallizing substances onto a layer of nuclei in motion, said nuclei being placed in a chamber equipped with a rotating perforated drum, and said spraying is provided by at least one nozzle for supplying compressed air;

- at least one step (b) drying said sprayed coating liquid, performed simultaneously with step (a);

step (c) collecting the coated solids thus obtained.

The subject of the present invention is also a solid coated form containing at least one coating layer containing:

- crystallizing substances, consisting of at least 50% mannitol, calculated on dry weight; And

- in some cases, binders, and the ratio of crystallizable substances / binders in terms of dry weight is more than 15.

Brief description of the figures

Fig. 1: a solid coated form according to the invention obtained from a coated liquid containing xylitol.

Fig. 2a - 2e: a solid pan according to the invention obtained from a pan containing mannitol.

Fig. 3a: solid coated form according to the invention obtained from a coated liquid containing sucrose.

Fig. 4a: solid coated form according to the invention obtained from a coated liquid containing erythritol.

Fig. 5a and 5b: non-inventive solid coated form obtained from a sucrose containing coating liquid.

Fig. 6: Maximum concentration of crystallizing substances in water as a function of liquid temperature.

Detailed description of the invention

Thus, a first object of the present invention are solid coated forms having at least one embossed imprint and/or at least one rib and/or that which determines its asymmetry, the coating layer of said solid coated asymmetric shape exactly following the shape the nucleus from which it is derived.

The solid forms according to the invention have particular irregular shapes, ie embossed impressions, ribs, or asymmetries. Examples of embossed prints include drawings (such as brand names) or inscriptions (brand names, molecule names, dosages, and the like). Embossed prints are found on the surface of solid forms, while the ribs are involved in defining the overall shape of the solid coated form. More specifically, these hard pans are characterized in that the pans from which they are obtained are themselves of such irregular shapes. In particular, it is understood that these irregular shapes of the original kernels are retained after panning. Specifically, this means that the inscriptions are readable and the drawings are identifiable. These irregular shapes also cover asymmetric shapes, i.e. shapes that do not have an axis of symmetry. It is understood here that the coating layer of solid coated asymmetric shapes exactly follows the shape of the kernels from which they are derived.

Preferably this solid form according to the invention has at least one embossed impression and/or at least one ridge, more preferably at least one embossed impression.

The subject of the present invention is also a solid coated form having irregular shapes, optionally as described above, characterized in that it contains at least one coating layer containing:

- crystallizing substances, consisting of at least 50% mannitol, calculated on dry weight; And

- in some cases, binders, and the ratio of crystallizable substances / binders in terms of dry weight is more than 15.

Preferably, the crystallizable coating materials of this solid coating form consist of at least 60% mannitol on a dry weight basis, preferably at least 70%, preferably at least 80%, preferably at least 90% and even exclusively from mannitol.

More preferably, in the coating layer of these hard coated forms, the ratio of crystallizable substances/binders on a dry weight basis is greater than 20, even greater than 30, even greater than 40. Preferably, the coating layer may also be free of binders.

When panning, "solid form" is traditionally understood to mean any presentation of coated substances in solid form ("solid panned form") or in a form that can be subjected to a panning procedure ("core"). Common examples are tablets, hard gelatin capsules, softgels, granules, microspheres, grains, seeds, biscuits, breakfast cereals, confectionery products such as chewing gum, lozenges, chewable lozenges, jellies, chocolates, fruits and vegetables, or products in powder and/or crystal form. These solid forms may be for food, pharmaceutical, veterinary, cosmetic purposes, for example. They may be intended for a person, an adult or a child, or an animal. It may also be a chemical or agrochemical product, although solid forms intended for oral consumption are preferred within the scope of the present invention. Preferably these solid forms are selected from tablets and chewing gum.

Preferably, the solid pans of the invention comprise at least one panning layer whose composition is identical to that of the panning liquid used in the panning process of the invention, provided that only what constitutes the dry matter of the panning liquid is taken into account here.

Preferably, in the solid pans according to the invention, the coating percentage is greater than 1%. This coverage percentage, otherwise known as "weight gain", is traditionally defined as follows:

(Weight of solid coated forms - weight of kernels) / weight of kernels x 100.

Preferably this coverage percentage is greater than 3%, preferably greater than 5%, preferably greater than 7%, preferably greater than 10%, such as at least 15% and even at least 20%.

The subject of the invention is also a panning process, particularly useful for making solid panned forms according to the invention, comprising:

- step (a) spraying a coating liquid containing a composition of crystallizing substances onto a layer of nuclei in motion, said nuclei being placed in a chamber equipped with a rotating perforated drum, and said spraying is provided by at least one nozzle for supplying compressed air;

- at least one step (b) drying said sprayed coating liquid, performed simultaneously with step (a);

step (c) collecting the coated solids thus obtained.

The equipment used to implement the method of the invention typically includes a plating liquid storage unit having at least one plating liquid outlet to the plating liquid spraying device. The coating liquid is applied by means of a spray device to the layer of nuclei located in the chamber, said chamber being equipped with a rotating drum to drive said layer of nuclei. More specifically, the drum is a rotating perforated drum and the spray device selected includes at least one compressed air nozzle. In addition, the equipment has an air inlet at the level of the drum chamber for drying the coating liquid. The exit of the drying air takes place, in particular, through the openings of the rotating drum, more particularly by suction of air from the room.

Elements of equipment useful for the invention are commercially available and their placement presents no particular difficulty to a person skilled in the art.

The dragee liquid useful for the invention contains a composition of crystallizing substances.

Traditionally, by "composition of crystallizing substances" is meant a composition consisting of substances capable of crystallizing upon evaporation of the solvent in which they are dissolved.

Preferably, the coating liquid crystallizable composition useful for the invention contains at least one substance selected from sugars and polyhydric alcohols, preferably selected from monomers and dimers.

Preferably sugars and polyhydric alcohols make up at least 50%, preferably at least 70%, and even more preferably at least 90% of the coating liquid's crystallizable composition, on a dry weight basis. Most preferably, the composition of the crystallising substances of the coating liquid consists entirely of substances selected from sugars and polyhydric alcohols.

In the present invention it is understood that, if we are talking about the dry weight of the components, this weight includes possible impurities.

Preferably, these sugars and polyhydric alcohols are selected from xylitol, sucrose, erythritol, mannitol, dextrose, isomalt, maltitol or, where appropriate, combinations thereof. Quite preferably these sugars and polyhydric alcohols are selected from sucrose, mannitol, xylitol, erythritol, or where appropriate combinations thereof, more preferably sucrose, mannitol, xylitol, or optionally combinations thereof.

Preferably, the composition of the crystallizing substances of the coating liquid consists entirely of one substance. Thus, for example and preferably, a composition of crystallizing substances useful for the invention is xylitol, or sucrose, or erythritol, or mannitol, or dextrose, or isomalt, or maltitol.

The concentration of crystallizing substances of the coating liquid is chosen so that the crystallizing substances can be dissolved in said coating liquid.

Typically, in particular if the coating liquid is an aqueous liquid, the coating liquid according to the invention has a concentration of crystallizing substances below 90%, this percentage corresponding to the dry weight of the crystallizing substances of the coating liquid relative to the total weight of said coating liquid. Preferably this concentration is less than or equal to 70%, preferably less than or equal to 60%, preferably less than 60%, even less than or equal to 55%, even less than or equal to 50%, even less than or equal to 45%, even less than or equal to 40%, even less than or equal to 35%, even less than or equal to 30%, even less than or equal to 25%, even equal to 20%. Typically, this concentration is above 10%, even at least equal to 15%, even at least equal to 20%.

Of course, the maximum concentration of crystallizing substances depends on the nature of these crystallizing substances, as well as on the temperature of the coating liquid. For xylitol, sucrose, erythritol, mannitol, dextrose, isomalt and maltitol, reference can be made, for example, to Figure 6, which shows the maximum concentrations of these crystallizing substances in water as a function of liquid temperature. Thus, for example, the concentration of crystallizing substances of the coating liquid at 20° C. is preferably less than or equal to 67% if the composition of the crystallising substances consists of sucrose, less than or equal to 15% if it is mannitol, less than or equal to 61% if it is maltitol, less than or equal to 63% for xylitol, less than or equal to 25% for isomalt, less than or equal to 27% for erythritol, less than or equal to 48% for dextrose.

In general, the coating liquid of the invention contains substances other than crystallizable substances, provided that this does not interfere with the properties required in the present invention, more specifically regarding the quality of the solid coated forms obtained and/or the ease of implementation of the method. Such other components are, for example:

- binders such as gum arabic, polyvinyl alcohol;

- dyes such as pigments, opacifiers such as titanium dioxide;

- flavors, sweeteners;

- active substances of interest, for example, from a pharmaceutical, nutritional, nutraceutical or phytosanitary perspective.

Preferably the solids content by weight of the coating liquid according to the invention is below 90%, preferably below 85%, preferably below 80%, preferably below 75%, preferably below or equal to 70%, preferably below or equal to 60%, preferably below 60%, even less than or equal to 55%, even less than or equal to 50%, even less than or equal to 45%, even less than or equal to 40%, even less than or equal to 35%, even less than or equal to 30%, even less than or equal to 25%, even equals 20%. Typically, this dry matter is greater than 10%, preferably at least 15%, more preferably at least 20%.

Thus, preferably, the dry matter of the coating liquid according to the invention consists of:

- 50.0 - 100.0%, calculated on the dry weight of the crystallizing substances, more specifically those described above;

- 0.0 - 50.0% based on dry weight of the other ingredients, more specifically those described above, the sum of these percentages being 100.0%.

Preferably, the dry matter of the coating liquid according to the invention contains crystallizing substances in an amount of at least 60.0% based on dry weight, preferably at least 70.0%, preferably at least 80.0%, preferably at least 90.0 %, even at least 94.0%, even at least 95.0%, even at least 96.0%.

As a rule, the dry matter of the coating liquid according to the invention contains pigments and/or dyes in an amount below 5.0% based on dry weight, preferably below 4.0%, preferably below 3.0%.

Generally, the dry matter of the coating liquid according to the invention contains opacifying agents in an amount below 5.0% on a dry weight basis, preferably below 4.0%, preferably below 3.0%, preferably below 3.0%, preferably below 2.0%.

In general, the dry matter of the coating liquid according to the invention contains binders in an amount below 15.0% based on dry weight, preferably below 10.0%, even below 8.0%, even below 5.0%.

Generally, the coating liquid used according to the invention is polar and preferably contains water as the main solvent, most preferably as the sole solvent.

According to a preferred embodiment, for reasons of simplicity and because it is possible, the panning process according to the invention uses a single panning liquid, ie the composition of the panning liquid is constant throughout the panning procedure.

Generally, the temperature of the coating liquid is chosen so that the crystallising substances can be dissolved in said coating liquid to be sprayed. Therefore, this temperature also depends on the amount of crystallizing substances present in the liquid. In the method according to the invention, this temperature is usually chosen in the range from 20 to 90°C. Preferably this temperature is below 85°C, preferably below 80°C, preferably below 75°C, preferably below 70°C, even below 65°C, even below 60°C, even below 55°C, even below 50°C , even below 45°C, even below 40°C, even below 35°C, even below 30°C. Typically, this temperature is at least 15°C, even at least 20°C. It corresponds, for example, to the ambient temperature, which usually ranges from 20 to 25°C.

According to a preferred embodiment, the coating liquid is stored in a single housing storage unit and/or the equipment useful for the method of the invention does not have a device for heating the coating liquid. Indeed, since the method according to the invention does not necessarily require the use of elevated temperatures of coating liquids, these devices are not mandatory in the method according to the invention.

For spraying the coating liquid, the number of compressed air nozzles used is traditionally chosen depending on the size of the coating chamber, according to the manufacturer's recommendations. Typically, this number of nozzles is between 1 nozzle and 2 nozzles per 40 cm area of the coating chamber diameter. This number of nozzles varies, for example from 1 to 10, for example from 1 to 6.

Preferably, only compressed air nozzles are used for spraying in the process according to the invention.

Preferably, the nozzles used according to the invention have an orifice whose diameter is chosen in the range 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 0.5 to 1.8 mm or 0.5 to 1.5 mm or 0.5 to 1.2 mm or 0.5 to 1.0 mm.

Preferably, the spray rate is chosen in the range from 0.5 to 20.0, preferably from 1.0 to 20.0, preferably from 2.0 to 20.0, for example, from 2.0 to 15.0, even from 2 .0 to 10.0 g/min/kg cores.

According to a preferred embodiment, the flow rate selected for spraying is increased during the panning procedure. More specifically, the inventors have found that for some crystallizable substances, the use of a low flow rate at the beginning of the panning allows favorable conditions for the first phase of crystallization, which occurs on the surface of the kernels. Then the flow rate can be increased in order to speed up the panning.

For atomization, the atomization pressure and crushing load are adjusted according to the flow rate and nozzle orifice and according to the manufacturer's recommendations. Typically, these atomization pressures and crush loads are chosen in the range of 0.5 to 4.0 bar, preferably 0.5 to 3.5 bar, for example 0.7 to 2.5 bar for atomization pressure and/ or 0.7 to 3.5 bar for crushing breaking load.

According to the present invention, the coating liquid is sprayed onto a layer of nuclei driven by a rotating drum.

The nature of these cores is preferably as described above for solid forms; we are talking, for example, about tablets or chewing gum. These cores may be completely unshelled or coated with one or more layers, for example by gum coating, film coating, even panning, said layers being preferably produced on the same equipment as the equipment used for the panning process according to the invention.

To set in motion the layer of kernels, the speed of rotation of the drum is selected depending on the dimensions of the chamber and the size of the kernels for panning. Generally, the speed is chosen in the range of 3 to 30 rpm, for example in the range of 10 to 20 rpm.

According to a preferred embodiment, more specifically for reasons of simplicity and/or amount of space occupied, and also because the method of the invention makes it possible to do so, setting the layer of nuclei in motion precludes the transfer of said nuclei along the longitudinal axis. More specifically, this means that the kernels are not transferred from one chamber to another during panning, i.e. they are panned in one chamber, and/or that the layer of kernels is not panned in the longitudinal chamber along which they move.

For drying, the selected drying air temperature is preferably below 100°C, preferably below or equal to 80°C, preferably below or equal to 75°C, preferably below or equal to 70°C, even below or equal to 65°C, even below or equal to 60°C, even less than or equal to 55°C, even less than or equal to 50°C, even less than or equal to 45°C, even less than or equal to 40°C, even less than or equal to 35°C, even less than or equal to 30 °C, even lower than or equal to 25°C. Typically, this drying temperature is at least 15°C, preferably at least 20°C.

For drying, the flow rate can be selected in the range of 50 to 8000 m ³ /h, for example in the range of 100 to 7000 m ³ /h, for example 100 to 1000 m ³ /h.

Preferably, the drying air exits by sucking air through the openings of the rotating perforated drum.

Preferably, the area of the perforated wall of the rotating drum useful for the invention is preferably at least 50% of the surface of said drum wall, preferably at least 60%, preferably at least 70%, preferably at least 80%, preferably at least 90%. Quite preferably, the wall of the drum is perforated over its entire surface.

Preferably, the temperature of the core bed during panning is at most 70°C, preferably at most 60°C, preferably at most 55°C, preferably at most 50°C, preferably at most 45°C, even at most 40°C, even not more than 35°C, not even more than 30°C, not even more than 25°C. As a rule, this core bed temperature during panning is at least 10°C, even at least 15°C.

Preferably before the start of panning, that is, before the start of spraying, the method according to the invention includes the step of heating the bed of panning kernels. More specifically, this step is designed to bring the bed of nuclei to a target temperature.

The coating method according to the invention simultaneously sprays and dries the sprayed liquid.

It is possible to introduce spreading ("pause periods") and spraying steps in the absence of drying, provided that this does not impair the properties required in the present invention, more specifically regarding the quality of the obtained solid coated forms and/or the ease of implementation of the method.

Preferably, the phases of the coating process, during which, in certain cases, spraying if desired is not carried out simultaneously with drying, are less than 50% of the coating process time, preferably less than 40%, preferably less than 30%, preferably less than 20%, preferably less than 10%, preferably less than 5%. Quite preferably, the panning does not include a spraying phase in the absence of drying.

Preferably possible pause periods (the period between two spraying phases during which neither spraying nor drying is performed) are less than 50% of the coating process time, preferably less than 40%, preferably less than 30%, preferably less than 20%, preferably less than 10%, preferably less than 5%. Quite preferably, the panning does not include a pause period.

Preferably, in hard coated forms obtained by the method according to the invention, the percentage of coating is more than 1%, preferably more than 3%, preferably more than 5%, preferably more than 7%, preferably more than 10%, for example, at least 15%, even at least least 20%.

Preferably this percentage of coverage per unit time is at least 0.05% per minute, preferably at least 0.10% per minute, preferably at least 0.13% per minute, even at least 0.15% per minute. minute, even at least 0.20% per minute, even at least 0.30% per minute.

In addition, the method of the invention may include conventional steps other than those aimed at panning solid forms, provided that this does not interfere with the properties required in the present invention, more specifically regarding the quality of the obtained hard panned forms and/or the ease of implementation of the method. Examples of other steps include, for example, gumming, smoothing, polishing, coloring. Preferably, if such steps are performed, they are carried out in the same equipment as the equipment used for the panning process of the invention. It is understood that some of these steps, such as gum coating or coloring, for example, can sometimes be equated to panning steps if the composition used contains such an amount of crystallizing substances that a layer of crystallizing substances, more specifically sugars and/or polyhydric alcohols, is actually formed. .

With regard to these other conventional steps, it is interesting to note that the panning performed by the method of the invention already allows a good level of smoothing of solid shapes to be obtained. In addition, staining can be carried out directly by adding colorants to the coating liquid.

The method of the invention may also include an initiation step. This initiation step consists in applying, once or repeatedly, the powdered composition to the bed of panning cores, or during panning, preferably during panning. Typically, this powder composition contains crystalline substances. Usually these crystalline substances are of the same nature as the crystallizing substances of the coating liquid, but may be different. The applied amount of the powder composition is usually below 10% by weight relative to the weight of the tablets, preferably below 5%.

Preferably, when using dextrose, isomalt, maltitol, or a combination thereof, the method includes an additional initiation step. Preferably, when using sucrose, xylitol, mannitol, erythritol, or a combination thereof, the method eliminates this initiation step.

Equipment useful for the invention may include other elements traditionally used in panning, provided that this does not interfere with the properties required in the present invention, more specifically regarding the quality of the obtained solid coated forms and/or the ease of implementation of the method.

In this regard, it is interesting to note that the prior art sometimes mentions the use of lump breakers, the task of which is to prevent the appearance of sticky lumps during panning. Such clod breakers are not necessary in the process of the invention. Thus, preferably, and because it is possible and advantageous within the process of the invention, the drum chamber used according to the invention does not contain clod breakers.

The invention will be better understood through the following examples, which are illustrative and non-restrictive.

Examples

1. Coating tests according to the invention

1.1. Used equipment

Equipment with the following characteristics was used:

- rotating perforated drum: diameter 30.48 cm, volume 2 l;

- anti-slip rails x 6;

- 1 compressed air nozzle (Schlick 970/7-1 S75); hole diameter 0.8 mm;

- peristaltic pump (Watson Marlow, model 323); head with three rollers (313 DW);

- tube: inner diameter 2 mm: outer diameter 6 mm.

1.2. Coating liquids

The coating liquids tested had the following compositions (% dry):

Characteristic GA PVA PVA2 b.f. N Tested crystallizing substances 96.5% 96.5% 94.5% 98.5% 95.5% Arabic gum* 2.0% - - - 2.0 PVA (polyvinyl alcohol) - 2.0% 4.0% - - Titanium dioxide 1.0% 1.0% 1.0% 1.0% - Blue pigment (Blue n. 1 Lake) 0.5% 0.5% 0.5% 0.5% - Natural blue pigment (GNT) - - - - 2.5%

* Introduced in the form of a solution with a solids content of 40% by weight

All of these coating liquids were stored in a single body storage tank and at ambient temperature (20-25ºC).

1.3. Nuclei

The following batches of kernels were used as a substrate for panning:

Characteristic Comp-SORB 900 g 330 mg sorbitol tablets (hygroscopic) with embossed imprints Comp-MANN 900 g mannitol tablets (non-hygroscopic) 330 mg CG gum (chewing gum) containing gum base, sorbitol, mint flavor, etc.

1.4. Methods and results

The general test conditions were as follows: operating pressure 4 bar; spray pressure and crushing load 1.0 or 1.3 bar (choose depending on the viscosity of the solution, according to the manufacturer's recommendations); pressure difference -0.25 mbar; drum rotation speed 18 rpm; air consumption for drying 100 m ³ /hour.

Prior to spraying, the bed of tablets was heated for 2 minutes to reach the desired temperature of the bed of cores. Then spraying and drying were carried out simultaneously during the whole process (no pause period). At the end of the drageeing, the spraying was stopped and the solid forms were dried for another 2 minutes.

The tables below present the results obtained, as well as the specific characteristics of the method in each test.

Trial
Xyl-INI Trial
Xyl-IN2 Trial
Xyl-IN3 Trial
Xyl-IN4 Trial
Xyl-IN5 Coating liquid Crystallising Substances xylitol xylitol xylitol xylitol xylitol Composition, characteristics GA PVA b.f. N N % dry matter 60% 60% 60% 60% 60% Coating method Kernels, characteristic Comp-
SORB Comp-
SORB Comp-
SORB Comp-
SORB CG Inlet air temperature (drying) 60°C 60°C 60°C 60°C 60°C Spray consumption 3.5→ 7.5 g/min. 3.5→ 7.5 g/min. 3.5→ 7.5 g/min. 3.5→ 7.5 g/min. 3.5→ 7.5 g/min. Observation data for sticking during the method No sticking No sticking No sticking No sticking No sticking Measured core layer temperature 40°C 40°C 40°C 40°C 40°C Method duration 60 minutes 60 minutes 60 minutes 60 minutes 60 minutes Solid coated forms Mass gain
(Weight Gain/min.) 20.0% (0.33%/ min.) 20.0% (0.33%/ min.) 20.0% (0.33%/ min.) 20.0% (0.33%/ min.) 20.0% (0.33%/ min.) figures 1. a) 1.b) 1.c) 1.d) 1.e) Surface feel smooth smooth smooth smooth smooth Color homogeneous homogeneous homogeneous homogeneous homogeneous Irregular shapes The overall shape is very clear, the embossed prints are well identified The overall shape is very clear, the embossed prints are well identified The overall shape is very clear, the embossed prints are well identified The overall shape is very clear, the embossed prints are well identified The overall shape is very clear, the embossed prints are well identified Trial
Man-INI Trial
Man-IN2 Trial
Man-IN3 Trial
Man-IN4 Trial
Man-IN5 Coating liquid Crystallising Substances mannitol mannitol mannitol mannitol mannitol Composition, characteristics GA GA PVA PVA-2 b.f. % dry matter 20% 20% 20% 20% 20% Coating method Kernels, characteristic Comp-
MANN* Comp-
SORB Comp-
SORB Comp-
SORB Comp-
SORB Inlet air temperature (drying) 25°C 55°C 55°C 55°C 55°C Spray consumption 2.2→ 8.5 g/min. 3.5→ 7.5 g/min. 3.5→ 7.5 g/min. 3.5→ 7.5 g/min. 3.5→ 7.5 g/min. Observations of adhesion during the method No sticking No sticking No sticking No sticking No sticking Measured core layer temperature 21-26°C 35°C 35°C 35°C 35°C Method duration 144 minutes 150 minutes 150 minutes 150 minutes 150 minutes Solid coated forms Mass gain
(Weight Gain/min.) 18.9% (0.13%/ min.) 20.0% (0.13%/ min.) 20.0% (0.13%/ min.) 20.0% (0.13%/ min.) 20.0% (0.13%/ min.) figures 2. a) 2.b) 2.c) 2.d) 2.e) Surface feel smooth smooth smooth smooth smooth Color homogeneous homogeneous homogeneous homogeneous homogeneous Irregular shapes The overall shape is very clear The overall shape is very clear, the embossed prints are well identified The overall shape is very clear, the embossed prints are well identified The overall shape is very clear, the embossed prints are well identified The overall shape is very clear, the embossed prints are well identified

*these cores did not have embossed prints

Sac-IN1 test Ery-IN1 test Coating liquid Crystallising Substances sucrose erythritol Composition, characteristics GA GA % dry matter 50% 25% Coating method Kernels, characteristic Comp-SORB Comp-SORB Inlet air temperature (drying) 70°C 70°C Spray consumption 3.5→ 6 g/min. 3.5→ 7.5 g/min. Observations of adhesion during the method Slight adhesion at the beginning, which gradually softens No sticking Measured core layer temperature 44-45°C 44-45°C Method duration 70 minutes 120 minutes Solid coated forms Mass gain
(weight gain/min.) 20.0% (0.29%/ min.) 20.0% (0.17%/ min.) figures 3. a) 3.b) Surface feel +/- smooth smooth Color homogeneous homogeneous Irregular shapes The overall shape is very clear, the embossed prints are well identified The overall shape is very clear, the embossed prints are well identified

lso-IN1 test Mal-IN1 test Coating liquid Crystallising Substances isomalt maltitol Composition, characteristics GA GA % dry matter 25% 33% Coating method Kernels, characteristic Comp-MANN* Comp-MANN* Initiation 40 g isomalt after spraying 20 g coating liquid, then 30 g isomalt per 40 g sprayed solution 50 g maltitol after spraying 35 g coating liquid Inlet air temperature (drying) 60°C 55°C Spray consumption 1.8→ 10 g/min. 1.7→ 13.3 g/min. Observations of adhesion during the method No sticking Clumping at the beginning, which gradually softens Measured core layer temperature 35-40°C 30-36°C Method duration 138 minutes 76 minutes Solid coated forms Mass gain
(weight gain/min.) 19.5% (0.14%/ min.) 15.0% (0.20%/ min.) Surface feel rough rough Color homogeneous homogeneous Irregular shapes The overall shape is very clear The overall shape is very clear

*these cores did not have embossed prints

1.5. Discussion

The method according to the invention makes it possible to effectively coat all kinds of solid shapes in a very simple way and makes it possible to successfully preserve complex irregular shapes such as embossed prints, ribs and asymmetric shapes.

In this way, the inventors have succeeded, for example, in coating tablets and chewing gum, whether they are hygroscopic ("Comp-SORB" and "CG") or not ("Comp-MANN"), while retaining the relief imprints present on their surface. .

Surprisingly, despite the constant moistening of the nuclei, the latter did not blur, and complex irregular shapes were preserved (the absence of “logo in-filing” (“filling in the form of the brand name”), that is, filling the grooves and cavities formed by relief prints). For example, in the "Man-IN1" to "Man-IN5" trials, only 20% solids coating liquid was used. Meanwhile, the coated tablets obtained had clearly visible irregular shapes (Figure 2a), in particular, the embossed prints were perfectly identifiable (Figures 2.b) to 2.e)).

In addition, the process according to the invention has other notable advantages which make it useful also for panning solid forms having a conventional shape.

The coating liquids used may contain all kinds of crystallizing substances and may be very simple in composition. For example, the "Xyl-IN3" and "Man-IN5" tests show that a binder-free coating liquid ("BF") is also suitable for the method of the invention. The method of the invention also makes it possible to successfully coat solid forms with coating liquids called "natural", which in particular do not contain titanium dioxide (Test "Xyl-IN4" using coating liquid "N").

In addition, the method according to the invention allows the use of very low solids concentrations, which is also completely new in panning. In all tests presented here, coating liquids were used, in which the solids content does not exceed 60%. Thus, the method according to the invention makes it possible to use carbohydrates that are poorly soluble in water (eg mannitol) for panning.

The method according to the invention also allows the use of relatively low drying temperatures. The main purpose of the "Man-IN1" test is to illustrate this effect, it shows that it is possible to pan with mannitol using a temperature of 25°C. The obtained solid coated forms have a very clear shape, exactly following the shape of the original kernels (Figure 2.a). The possibility of using particularly low drying temperatures makes it possible, in particular, to obtain the temperature of the core layer, which will also be low, which makes it possible to pan the compositions of the cores containing heat-labile ingredients, as is the case, as is the case with certain active substances, more specifically with pharmaceutical ingredients. . Thus, in the test "Man-IN1" the temperature of the layer of tablets does not exceed 26°C.

The temperature of the coating liquid can also be very low, since the process according to the invention does not necessarily require that the liquid contain a large amount of crystallizing substances in dissolved form. In these tests, the coating liquids used were indeed at ambient temperature (20-25°C). In addition to creating favorable conditions for the implementation of the method, it allows the use of thermolabile ingredients in these liquids.

Finally, the solid forms obtained by the method of the invention are also satisfactory in terms of their color and surface feel.

2. Comparative coating tests

In this part, the inventors have attempted to coat 1 kg Comp-SORB tablets having embossed prints according to the above document US 2008/0026131 A1.

2.1. Used equipment

Equipment with the following characteristics was used:

- rotating drum: diameter 30 cm;

- anti-slip rails x 8;

- 1 compressed air nozzle (BINKS 460); hole diameter 0.8 mm;

- peristaltic pump (Watson Marlow, model 323); head with three rollers (313 DW);

- tube: inner diameter 2 mm: outer diameter 6 mm.

2.2. Coating liquids

According to US 2008/0026131 A1, Example 1, the following coating liquids were used:

- "gum syrup": composition (% dry.): 96.0% sucrose; 4.0% gum arabic (introduced in the form of a solution with a solids content of 40% by weight), solids content: 72%.

- "smoothing syrup": composition (% dry.): 97.0% sucrose; 2.0% glucose syrup; 1.0% titanium dioxide, solids content: 70%.

- "tinting syrup": composition (% dry.): 98.0% sucrose; 2.0% blue pigment (Blue n. 1 Lake), solids content: 69%.

The temperature of these liquids was adjusted, if necessary, in such a way as to achieve good dissolution of the components.

2.3 Methods and results

In the tests described below, the conditions of Example 1 of US 2008/0026131 A1 (drying temperatures, solids content, etc.) were met. Parameters such as spray flow or drum speed were adapted to the size of the panning chamber available to the inventors.

Sac-CP1 test:

The first test was carried out according to the table below by performing several cycles, each consisting of a spraying phase, then a pause (spreading) period, followed by a drying phase:

Phases Cycles Spraying (consumption, duration) Pause (duration) Drying (°C, duration) Drum rotation speed Coating with gum (gum syrup) 1-9 20 g/min, 1 min. 1 min. 27°C, 7 min. 19 rpm

This test was not successfully completed and was terminated due to too much sticking, despite the higher drying capacity of the equipment compared to that described in US 2008/0026131 A1 (50 m ³ /hour vs 15.3 m ³ /hour) .

A second test was carried out to avoid this sticking phenomenon and to fully reproduce Example 1 of US 2008/0026131 A1.

Sac-CP2 test:

Due to the failure of the Sac-CP1 test, the first cycle of the first phase was changed: the sticky nuclei were separated by the efforts of the operator, and the test conditions were changed. This test was carried out in accordance with the table below:

Phases Cycles Spray (flow rate, duration) Pause
(duration) Drying (°C, duration) Drum rotation speed Coating with gum (gum syrup) 1 20 g/min
1 min. 1 min. 27°C, 13 min. 19 →28 rpm. 2-9 20 g/min
1 min. 1 min. 27°C, 7 min. 19 rpm Smoothing (smoothing syrup) 1-4 20 g/min
1 min. 1 min. 30°C, 6 min. 19 rpm 5-9 20 g/min
1 min. 1 min. 30°C, 6 min. 23 rpm Coloring (tinting syrup) 1-8 40 g/min
22.5 s. 1 min. 25°C, 6 min. 28 rpm 1-3 40 g/min, 9 sec. 4 min. 25°C, 30 sec. 28 rpm

The results obtained are shown in Figure 5.a). Dragee thus tablets are very rough, have a rough and rounded shape. The brand names and prints that were on the cores are filled in and cannot be identified. The inventors stated that the surface of the tablet was destroyed from the first coating cycles. The tablets dissolved from the first two minutes, despite the high solids content of the coating liquids used, in addition, crystallization was very difficult.

Sac-CP3 test:

A third trial was conducted in which the single panning phase "Smoothing" from the Sac-CP2 trial was performed. Similar results were obtained to those of the Sac-CP2 test (Figure 5.b)): the coated tablets were rough and rounded and the embossed impressions were filled.

Claims (9)

1. Coating method for preparing a solid coated form, including - step (a) spraying a coating liquid containing a composition of crystallizing substances, including at least one substance selected from sugars and polyhydric alcohols, onto a layer of nuclei in motion, wherein said nuclei are placed in a chamber equipped with a rotating perforated drum, and said spraying is provided using at least one nozzle using compressed air; - at least one step (b) drying said sprayed coating liquid, performed simultaneously with step (a); - step (c) collecting the coated solids thus obtained, wherein the coated hard form is selected from tablets, hard gelatin capsules, soft capsules, granules, microspheres, grains, seeds, biscuits, breakfast cereals, confectionery and products in powder form and/ or crystals. 2. Coating method according to claim 1, characterized in that sugars and polyhydric alcohols constitute at least 50%, preferably at least 70%, and even more preferably at least 90% of the composition of the crystallizing substances of the coating liquid, calculated on the dry weight . 3. Coating method according to claim 1 or 2, characterized in that said sugars and polyhydric alcohols are selected from xylitol, sucrose, erythritol, mannitol, dextrose, isomalt, maltitol, or combinations thereof. 4. Coating method according to claim 3, characterized in that said sugars and polyhydric alcohols are selected from xylitol, sucrose, erythritol, mannitol, or combinations thereof. 5. Coating method according to any one of claims 1 to 4, characterized in that said coating liquid according to the invention has a concentration of crystallizing substances below 90%, this percentage corresponding to the mass of crystallizing substances of the coating liquid relative to the total weight of said coating liquid. 6. Coating method according to any one of claims 1 to 5, characterized in that the nozzles for supplying compressed air have an opening, the diameter of which is selected in the range from 0.1 to 2.8 mm.

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