FR2929294A1 - APPARATUS FOR PLASMA TREATMENT OF HOLLOW BODIES - Google Patents

Abstract

The present invention relates to an apparatus for the plasma treatment of the inner walls of at least one hollow body comprising: - at least one support (4) adapted to the external dimensions of the hollow body (12), - at least two metal electrodes (8) , characterized in that said apparatus comprises means (5) for adjusting the distance between said electrodes and a system for plasma treatment of the inner walls of at least one hollow body, said system comprising said apparatus.It also relates to a method for the coating by chemical vapor deposition of the inner walls of at least one hollow body employing said system.It also relates to a hollow body having an L / D ratio of greater than or equal to 3, preferably greater than or equal to 5, L being the length and D being the diameter of said hollow body, said hollow body having an inner lining of thickness between 300 and 500 nm with varying less than 20%.

Description

The invention relates to an apparatus and a method for the plasma treatment of hollow bodies, for example syringes, having low internal diameters. It relates more particularly to the coating of the inner walls by the technique of chemical vapor deposition of said hollow bodies. If the chemical vapor deposition techniques have already been widely used for the coating of tubes and / or hollow body coatings obtained are often insufficiently regular and have defects that are not compatible with the specifications imposed by example in the field of syringe production for the pharmaceutical industry when said hollow body have a long length and a small section.

Such methods for coating the interior of hollow bodies have been described for example in US5702770, which teaches the use of said hollow body as the reaction chamber subjected to a vacuum before filling with the gas to be used for make the deposit. The use of the hollow body as a chamber avoids the use of an external chamber that should be cleaned, maintained and integrated into the industrial process. The electrodes for producing the energy can be moved to improve the homogeneity of the deposit and also adapted to the different hollow bodies to be coated. The adaptation of the device to the different objects to be processed according to the productions will also be easier because only the electrodes and the gas will be modified according to the objects to be coated. In US-2002/0155218, a method for improving the uniformity of the coating comprising a closing phase of one of the open ends of the hollow body to be coated by a gas-tight device. This closure provides a more homogeneous and more consistent deposit on the entire inner surface of the treated hollow body. US Patent 5972436 discloses a method for improving the uniformity of the coating, by a method comprising a step of preheating the interior of said hollow body by initiating a plasma by filling it with oxygen and then triggering of the plasma when the desired temperature is reached, supply of gas which will be used for the coating with initiation of a new plasma. The coating of only a portion of the hollow body to be treated has been described for example in US-5318806, which teaches a method for obtaining a gradient of the chemical deposition performed on the object as a function of the positioning of said object by very high density plasma that is generated in a volume surrounding the electrode. The more the surface of the object is close to the electrode, the more intense the plasma is, and the greater the deposit, the further the surface of the object is from the electrode, the lower the deposit. A method for the simultaneous coating of several parts with uniformity of deposited layers and reproducibility but also a good yield has been described in patent application US-2005/0005853. The method allows from a single source of microwaves, thanks to a waveguide whose different structures are described, to simultaneously generate in all the chambers, which can be formed by the parts to be coated, a plasma. US Patent 6177148 discloses a method leading to a uniform simultaneous coating of several parts using a pulsed process with adjacent chronologically controlled antennas which allow to feed the electrodes of two adjacent objects to be coated at different times. to avoid interference between the plasmas thus created. In addition to the above problems of homogeneity and simultaneity of coating of several parts, it appears that the lining of small diameter parts poses particular problems that have been described in US-4948628, which describes an apparatus for generating a plasma for coating the inner walls of a small diameter tube, said apparatus comprising a diaphragm that separates two chambers into a first chamber equipped with a gas inlet and a second chamber connected to a vacuum source . A dielectric protects the electrodes from any plasma discharges outside the area between the two electrodes. The pressure difference between the two chambers allows maintaining a pressure difference between the proximal end and the distal end of the tube to obtain a uniform deposit at both ends and a flow of gas within said pipe.

The present invention solves the above problems and allows to perform coatings whose thickness variations are small inside hollow body having a long length and a small diameter while allowing coating all or part of said hollow bodies. The present invention also makes it possible to carry out said coatings simultaneously on series of hollow bodies thus allowing an industrialization of the process.

The present invention consists of an apparatus for the plasma treatment of the inner walls of at least one hollow body comprising: at least one support adapted to the external dimensions of the hollow body, at least two metal electrodes, characterized in that said apparatus comprises means for adjusting the distance between said electrodes.

It relates to an apparatus according to the invention, characterized in that the means for adjusting the distance between the electrodes include a stack of insulating spacers. The presence of these means makes it possible to adapt the device to the length of the hollow body or to cover only a portion of said hollow body by positioning the electrodes at the level where the interruption of the coating is desired. In one embodiment the coating height is between the flange and the shoulder formed before the tip of the syringe preferably on the length corresponding to the stroke of the piston.

Chemical Vapor Deposition (CVD Chemical Vapor Deposition) is a method of depositing thin films from gaseous precursors. The principle consists of injecting gaseous precursors under a controlled atmosphere, then the substrate is heated and the chemical deposition reaction takes place on the surface after adsorption of the gaseous reactants. Preferably, the plasma enhanced chemical vapor deposition (PECVD or PACVD) is used in the present invention. According to the invention the apparatus consists of adjacent modules assembled, each module comprising a support adapted to receive at least one hollow body. The device thus has a flexible capacity and can be adapted to perform a coating on a set of hollow body comprising a variable number of hollow body and allows the adaptation of the size of the batch to the needs of production. The apparatus also includes screens that can be placed on one of its outer faces, on either side and / or at the bottom of the modules, to obtain a uniform and intense distribution of the plasma inside. hollow bodies. The apparatus according to the invention is suitable for a cylindrical hollow body having a L / D ratio greater than or equal to 3, preferably greater than or equal to 5, L being the length and D being the diameter of said hollow body. . The support of the apparatus according to the invention is particularly suitable for syringe bodies [00021] Said apparatus further comprises a lid comprising means for delivering a gas into the interior volumes of said hollow body. In one embodiment, said cover forms with the support an intermediate chamber for distributing the gas in the interior volumes of several hollow bodies. In one embodiment, the gas can escape through the end opposite the end allowing the introduction of gas into said hollow body, the end of the hollow body forming an exhaust means for the gas. When this end has an opening of a diameter smaller than that of the opening for the introduction of the gas, for example when said hollow body are syringes, on which are mounted the needles, the difference in diameter between the hollow body and the needle being capable of creating an overpressure in the hollow body, an exhaust means constituted by an orifice is provided at the upper part of the apparatus. Said exhaust means is for example an orifice placed at the end also allowing the introduction of the gas. In this embodiment a gas exhaust channel is provided on the upper part of the lid. Said invention thus makes it possible to coat the inner walls of hollow bodies, one end of which is closed or of which one end is partly obstructed, for example syringes on which the needles have been previously fixed without risk of depositing coating in the needles. , the electrodes can be positioned at a level higher than that of the electrodes.

In one embodiment, the plasma treatment is a coating treatment by chemical vapor deposition. In one embodiment, the plasma treatment is an oxidative plasma cleaning treatment. By oxidizing plasma is meant the creation of a plasma after filling the hollow body with a gaseous mixture containing essentially oxygen. In one embodiment, two successive treatments are carried out, an oxidizing plasma in the presence of oxygen, and after evacuation of the oxygen and filling of the hollow body with suitable gaseous precursors, a coating treatment is carried out by chemical deposition. in the vapor phase. The present invention also relates to a system for the plasma treatment of the inner walls of at least one hollow body, said system comprising: - an apparatus according to the invention as defined above, - a chamber adapted to contain said apparatus, - means for creating a plasma discharge between said electrodes, - means for distributing a gas in the interior volume of said hollow body,

In one embodiment, said chamber further comprises: means for creating and maintaining a predetermined pressure level in the apparatus.

In one embodiment, the predetermined pressure level is the vacuum, for example a mean vacuum of 1 to 10-3 mbar (102 to 10 -5 Pa) or a high vacuum of 10-3 to 10-7 mbar. (10-1 to 10-5 Pa).

In another embodiment, the predetermined pressure level is atmospheric pressure, ie approximately 101 325 Pa. The means for creating the plasma discharge between the two electrodes are radio-frequency means in one embodiment. or in another embodiment of the microwaves. In a variant of the system at least one of the electrodes is connected to the ground.

The invention also relates to a process for coating by chemical vapor deposition of the inner walls of at least one hollow body comprising the steps of: a) positioning said hollow body in the support of an apparatus according to the invention; invention as defined above, b) create and maintain a predetermined level of pressure in said apparatus, c) introduce a gas into the internal volume of said hollow body, d) create a plasma discharge between the two said electrodes [00037] In an embodiment the predetermined pressure level is the vacuum. In another embodiment, the predetermined pressure level is the atmospheric pressure. The gas is chosen according to the treatment and / or the targeted coating. When the vapor phase deposition is carried out cold, the gas is chosen from the group consisting of hexamethyldisiloxane (HMDSO), polyvinylidene chloride, fluorocarbon, silane derivatives, methane, trimethylstannate (Sn ( CH 3) 3 alone or in admixture with air or oxygen When the vapor phase deposition is carried out cold the gas is selected from the group consisting of aluminum trioxide, hexamethyldisiloxane (HMDSO), silane derivatives, methane, alone or in admixture with air or oxygen. [00042] With the method and the apparatus, the gas introduced and dispensed via the lid will be distributed in the hollow bodies and only in the hollow bodies thanks to the pressure difference between the inside and the outside of the hollow body. [00043] The invention also relates to a glass syringe body coated according to a method according to In one embodiment, the invention is the glass is borosilicate The invention also relates to a plastic syringe body coated according to a method according to the invention. In one embodiment, the plastics material is propylene or a cyclopolyolefin, a generic term designating, for example, a mixture of resins such as ZEONEX resins supplied by ZEON CHEMICALS. The invention also relates to a hollow body having a ratio L / D greater than or equal to 3, preferably greater than or equal to 5, L being the length and D being the diameter of said hollow body, said hollow body having an inner coating with a thickness of between 300 and 500 nm, with variations of thickness less than or equal to 20%.

In one embodiment, the invention relates to a method for cleaning by oxidative plasma the internal walls of at least one hollow body comprising the steps of: a) positioning said hollow body in the support of an apparatus according to the invention; the invention as defined above, b) create and maintain a predetermined level of pressure in said apparatus, c) introduce oxygen into the internal volume of said hollow body, d) create a plasma discharge between the two said electrodes. In a preferred embodiment, the apparatus comprises four spacers which are placed in the holder to adapt the apparatus to glass syringe bodies with a capacity of 1 milliliter. [00048] Two screens are also added at both ends of the support, to obtain an intense and uniform plasma inside the syringe bodies.

The present invention will be better understood from the figures representing a particular embodiment of the invention. Figure 1 shows an exploded view of an apparatus according to the invention. Figures 2 and 3 show a general view of a module of the apparatus according to the invention in two mounting modes. [00052] FIG. 4 represents a general view of an apparatus according to the invention. FIG. 5 represents a sectional view along the axis XX of an apparatus according to the invention. Figure 6 shows a syringe body having a coating on a portion of the body length of the syringe. [00054] FIGS. 7, 8 and 9 represent a schematic view of the measurement zones and the contact angles. The apparatus for the plasma treatment shown in the form of an exploded view in FIG. 1 comprises a cover 1 having on its lower surface recesses 10 forming means for delivering the gas into the interior volumes of the hollow bodies and forming with the lower support a gas distribution chamber in the hollow body. The illustrated module comprises two electrodes 8, the surface of which has lights capable of receiving the hollow bodies 12 shown in the exploded view and which are needleless syringe bodies. The apparatus also comprises a support 4 comprising lights adapted to the hollow body mentioned above. Is also represented insulating spacers 5 to adapt the distance between the electrodes 8. Screens 6 to be placed on each side of the modules, to obtain a uniform distribution of the plasma inside the hollow bodies are also shown. Joining means, namely rods 13, nuts 14, butterfly nuts 15 and screws 16 are also shown to assemble the components described above. In operation the modules, namely the electrodes 8, the support 4 and the spacers 5 are assembled before placing the hollow body and then the cover 1 and screens 6. The apparatus is then placed in a chamber, the electrodes are connected to a source of energy, and the orifices 11 are connected to a network which allows to evacuate inside the hollow body and then to inject the gas inside said hollow body.

Figures 2 and 3 are shown a general view of a module of the apparatus according to the invention in two mounting modes. In Figure 2, a mounting comprising a lid 1 of the electrodes 8, a support 4 spacers 5 and a screen 6 placed below the device. The lid has a gas supply port 11. In the assembly of FIG. 3, the same apparatus is shown, but to enable the method to be applied to syringes comprising needles, the lid used comprises a degassing orifice 2. The modules thus mounted can then be assembled to obtain a apparatus, which comprises a plurality of modules comprising a lid 1 comprising a gas supply port 11, a support 4, spacers 5, electrodes 8 and screens 6, in which hollow bodies according to the invention have been placed, such as FIG. 5 shows a cross-section along the axis XX of an apparatus as shown in FIG. 4. Hollow bodies 12 held in supports are placed in said apparatus. 4 which surmount spacers 5 which are placed between the electrodes 8. screens 6 are placed between each module. The assembly carried out comprises five parts, A, B, C, D and E. The parts A and B being intended to receive hollow bodies carrying a needle. For this purpose a degassing orifice 2 is provided to allow the return of the injected gas. In the modules C, D and E, the hollow bodies intended to be coated do not comprise a needle, degassing may be performed by the distal end of said hollow body, namely the zone 22 of said hollow body. These modules therefore do not have a degassing hole.

In Figure 6 is shown a syringe body having a coating 24 over a portion of the body length of the syringe. The coating is deposited on a length L of the body of the syringe, the total length of the body being represented by a length L and the diameter by the letter D. All of these variables are used in the rest of the text, especially in the examples and in the tables, to characterize the bodies of the syringes subjected to a treatment according to the invention. [00059] The syringe body shown in FIG. 7 illustrates the measurement zones of the contact angles, namely at 20 the flange area, at 21 the center of the syringe body, and at 22 the so-called area of the syringe area. needle. Figures 8 and 9 are shown contact angles with water on the surface of a substrate. In Figure 8 is shown a hydrophilic surface 25 not coated and a drop 23 which has an angle of contact with the weak surface. In Figure 9 is shown a hydrophobic surface 24 having a coating on which is positioned a drop 23 with a high contact angle with said surface 24.

The invention will be better understood on reading the following examples. 1) General Appearance [00064] All the examples are carried out in glass syringes, brand BD Hypak TM or syringes in polymer CCP (Crystal Clear Polymer or cyclopolyolefin). The gas mixture is composed of 20 SCCM of air and 3.5 SCCM (Standard Cubic Centimeter Minute) of HMDSO (HexaMethylDiSiloxane). The plasma is generated by a radio scanning frequency of 18 MHz and a power of 400 V (peak to peak). The coating is carried out in a support containing at least one row of ten syringes. The composition of the coatings is determined according to the method of X-ray photoelectron spectroscopy (XPS). The XPS analysis is performed using a spectrometer (SSX200, Surface Science) employed at an Al Kn achromatic X-ray source (486.6 eV) operating at 10 kV with a power of 225 Watts. The spectra are obtained with a passing energy of 150 eV for all the samples to determine which elements are present in the few nanometers of the upper part of the surface of the coating. The value of the angle between the surface and the direction of the electron detection is 35 °. The working pressures are 4x10-9 torr and the analysis zone is a circle with a diameter of 0.84 mm. The base area of the peak area is removed before analyzing the spectra. The shapes of the lines used for the curve-fitting analysis are 80% Gaussian and 20% Lorentzian for the elements C l s and O 1s.

The ratios between each element expressed in percentages were calculated using peak area based on acquisitions and subtraction of baseline. The angles of contact with the water of the different coatings were measured according to the following method: after coating, the rolls are cut using a diamond wire saw and the contact angles are measured along the length of the cylinder using an automatic goniometer equipped with a software that corrects the curve of the cylinder during the measurement of the contact angle. A homogeneous coating within the barrel of the syringe corresponds to water contact angles measured at three different locations within the coated barrel (see Figures 7, 8 and 9). The angles of contact with water are expressed in degrees.

Regarding the L / D ratio, for all the samples it is equal to 6.3 cm, L being equal to 5 cm and D being equal to 0.8 cm. The length of the body of the syringe on which a coating is made (coating length) L is likely to vary (see Figure 6).

Example 1 [00070] Influence of the L / D ratio for the coating of needleless glass syringes.

A plasma coating is created on the syringes that are placed in the support. With a f / D ratio of 5.7, it is possible to create a plasma deeper inside the syringes compared to a ratio of 4.4 (see results in Table 1 below).

Table 1 [00072] Angle of contact with water inside glass syringes L / D Collarette Medium Needle 4.4 99.2 (0.7) 98.2 (1.1) 95.7 (1 , 2) 5.7 96.9 (2.0) 96.1 (1.7) 94.5 (1.3) Uncoated body 46.0 (9.7) 45.7 (9.3) 52 (7,3) In conclusion, it is possible to obtain a coating using the apparatus and method according to the invention since the contact angles are initially between 45 ° and 53 ° on uncoated glass and more than 90 ° after deposition of the coating. Furthermore, with a ratio of 5.7 the difference between the contact angles with the water is lower than with a ratio of 4.4, this shows a more homogeneous coating within the length of the body of the syringe.

Example 2 [00074] Syringe coating with needles

With this invention, it is possible to create a plasma inside syringes even if they have a needle attached to one end. Thanks to the method according to the invention, the stainless steel needles do not interact with the plasma (see results in Table 2). The same plasma quality can be produced in syringes with or without a fixed needle.

Table 2 [00076] Control of plasma inside the body of syringes with fixed needles. L / D 5.7 Collar Medium Needle Needle syringe 96.9 (2) 96.1 (1.7) 94.5 (1.3) Needle syringe 94.7 (3.9) 92.4 (2) 9) 91.9 (2.5) Example 3 [00077] Verification of electrode positioning efficiency [00078] The optimum distance between two electrodes to obtain a homogeneous and intense plasma over the entire length of the syringe (100 °), corresponds to a ratio of 6.3.

If the f / D ratio is too high (6.9), then the plasma is created outside the support, and polymerization residues are deposited at the end of the collar, inside the cylinder. The measurement of the contact angle requiring a surface that is not contaminated by particles is therefore distorted. If the ratio is less than 6.3 (5.7), then the plasma is not formed over the entire length of the syringe, as illustrated by the variation of the 30 angle values. contact in Table 3 below.

Table 3 [00081] Plasma control inside glass syringes with adjustment of electrode positioning L / D Collar Medium Needle 5.7 94.7 (3.9) 92.4 (2.9) 91 , 9 (2.5) 6.3 100.3 (3.7) 100.2 (1.8) 100.8 (1.4) 6.9 98.7 (2.4) 100.7 (1) , 8) 100.2 (1.7) 7.6 N / AN / YE / A Example 4 [00082] Optimization of plasma for coating syringes with needles placed by adding a screen.

The addition of a shield on each side of the holder reduces plasma discharge to the outside of the device and creates a more intense and uniform plasma inside the syringe barrel (see Table 4).

Table 4 [00084] Plasma Control Inside Glass Syringes with Addition of a Screen on Each Side of the Bracket L / D = 6.3 Medium Needle Collar No Screen 100.3 (3.7) 100, 2 (1.8) 100.8 (1.4) Side Screens 100.0 (1.6) 97.7 (1.7) 97.3 (1.3) [00085] The coating on the sides The interior of the syringe body is more homogeneous when screens are used on the sides of the device because the measured standard deviation is lower. Example 5 [00086] Coating Test with Multiple Rows of Glass Syringes

Different supports with two, three or four rows of syringes to be coated were tested, the results are summarized in Table 5 below. It is possible to coat glass syringes in a device with several rows of syringes as shown by the contact angles obtained.

Table 5 L / D = 6.3 Collar Medium Needle Uncoated Glass 46.0 (9.7) 45.7 (9.3) 52.6 (7.3) Two Ranks 92.8 (1.0) 87 , 8 (2.0) 74.7 (6.1) Three ranks 92.1 (0.9) 86.2 (2.7) 69.5 (5.2) Four ranks 70.8 (0.9) ) 68.1 (1,1) 66,7 (1,4) Example 6 [00088] Use of inert or oxidizing gases on glass or syringes made of CCP (Crystal Clear Polymer) [00089] It is possible in this case device with a ratio f / D = 6.3 to use different gases like oxygen or air with HMDSO. The results obtained are summarized in the table below on syringes with an L / D ratio = 6.3. Using air, the coating is composed of oxygen, silicone, carbon and nitrogen, it is a hydrophilic coating, whereas using only oxygen, the coating is composed only of carbon, silicone and oxygen and becomes more hydrophobic. In this case, the ratios oxygen / HMDSO and air / HMDSO are respectively 2 and 10.10 Table 6 [00090] Comparison of the coating composition and the wettability on glass syringes according to the ratios of gas Glass Collerette Medium Needle C % 0% Si% Other Not coated 46.0 (9.7) 45.7 (9.3) 52.6 (7.3) 16.8 52.9 25.1 Na = 5.2 Oxygen / HMDSO 62 , (3.0) 58.3 (2.6) 61.6 (2.9) 12.7 53.4 27.9 0 Air / HMDSO 53.6 (5.6) 57.3 (9, 9) 63.3 (5.6) 41.5 27.2 9.1 N = 20.4 Example 7 [00091] Test on CCP syringes

[00092] A uniform and intense plasma is also generated in CRP (Crystal Clear Polymer) cylinders 10 (of the same dimensions as the BD Hypak TM 1 milliliter syringes) using the same device as that described in Example 4. with a decrease in power to 300 volts. As obtained previously, it is possible to obtain a more hydrophilic coating by using a mixture of air and monomer (HMDSO) in comparison with a mixture of oxygen and monomer. In this case, the ratios Oxygen / HMDSO and Air / HMDSO are respectively 1 and 10 (see Table 7).

Table 7 [00094] Comparison of Coating Composition and Wettability on CCP Syringes as a Function of Gas Ratio CCP Collerette Medium Needle C% 0% Si% N% Not Coated 88.4 (2.1) 89.5 (3.4) 90.7 (2.5) 97.5 2.5 0 0 Oxygen / HMDSO 107.9 (1.3) 108.0 (0.9) 107.6 (1.2) ) 53.4 20.7 25.9 0 Air / HMDSO 62.7 (3.8) 67.4 (2.7) 69.8 (3.0) 69.1 18.4 6.5 6.05

Claims (30)

REVENDICATIONS1. Apparatus for the plasma treatment of the inner walls of at least one hollow body comprising: - at least one support (4) adapted to the external dimensions of the hollow body (12), - at least two metal electrodes (8), characterized in that said apparatus comprises means (5) for adjusting the distance between said electrodes. 2. Apparatus according to claim 1, characterized in that the means for adjusting the distance between the electrodes are insulating spacers (5). 15 3. Apparatus according to any preceding claim characterized in that it consists of adjacent modules assembled, each module comprising a support (4) adapted to receive at least one hollow body. 4. Apparatus according to any one of the preceding claims, characterized in that it comprises at least one screen (6) placed on one of its outer faces. 5. Apparatus according to any one of the preceding claims, characterized in that it is adapted to a cylindrical hollow body (12) having a L / D ratio greater than or equal to 3, preferably greater than or equal to 5 L being the length and D being the diameter of said hollow body. 6. Apparatus according to any preceding claim characterized in that said support is adapted to syringe bodies. 7. Apparatus according to any preceding claim characterized in that it further comprises a lid (1) having means (10) for delivering a gas in the interior volumes of said hollow body. 30 8. Apparatus according to any one of the preceding claims characterized in that said lid forms with the support an intermediate chamber for distributing the gas in the interior volumes of several hollow bodies. 9. Apparatus according to any one of the preceding claims characterized in that one end of the hollow body forms an exhaust means (2) for the gas. 10. Apparatus according to any preceding claim characterized in that a gas exhaust channel is formed on the upper part of the support. 11. Apparatus according to any preceding claim characterized in that the plasma treatment is a chemical vapor deposition coating treatment. 12. Apparatus according to any preceding claim characterized in that the plasma treatment is an oxidizing plasma cleaning treatment. 13. System for the plasma treatment of the interior walls of at least one hollow body, said system comprising: an apparatus according to one of the preceding claims, a chamber adapted to contain said apparatus, means for creating a plasma discharge. between said electrodes, means for distributing a gas in the interior volume of said hollow body, The system of claim 13, characterized in that said chamber further comprises: - means for creating and maintaining a predetermined pressure level in the apparatus, 15. System according to any one of claims 13 or 14, wherein the predetermined pressure level is the vacuum. The system of any one of claims 13 or 14, wherein the predetermined pressure level is atmospheric pressure. 17. System according to any one of claims 13 to 16, wherein the means for creating the plasma discharge between the two electrodes are radio frequency means. 18. System according to any one of claims 13 to 16, wherein the means for creating the discharge between the two electrodes are microwaves. 15 19. System according to any one of claims 13 to 18, wherein at least one of the electrodes is connected to the ground. 20. Process for chemical vapor deposition coating of the inner walls of at least one hollow body comprising the steps of: a) positioning said hollow body in the support of an apparatus according to any one of claims 1 to 18 , b) creating and maintaining a predetermined level of pressure in said apparatus, c) introducing a gas into the internal volume of said hollow body, d) creating a plasma discharge between the two said electrodes 25 21. The method of claim 20, characterized in that the predetermined pressure level is the vacuum. 22. The method of claim 20, characterized in that the predetermined pressure level is the atmospheric pressure. 23. Method according to one of claims 20 to 22, characterized in that said gas is selected from the group consisting of hexamethyldisiloxane (HMDSO), polyvinylidene chloride, fluorocarbon, derivatives of silane, methane, trimethylstannate (Sn (CH3) 3, alone or mixed with air or oxygen. 24. Method according to one of claims 20 to 22, characterized in that said gas is selected from the group consisting of aluminum trioxide, hexamethyldisiloxane (HMDSO), derivative silane derivatives, methane, alone or mixed with air or oxygen. 25. Glass syringe body coated by a process according to one of claims 20 to 24. Syringe body according to claim 25, characterized in that the glass is borosilicate. 27. Plastic syringe body coated according to a method according to one of claims 20 to 24. 28. Syringe body according to the preceding claim, characterized in that the plastic material is propylene or a cyclopolyolefin. 29. Hollow body having an L / D ratio greater than or equal to 3, preferably greater than or equal to 5, L being the length and D being the diameter of said hollow body, said hollow body having an inner lining of a thickness between 300 and 500 nm with variations of less than 20%. 30. A method for oxidatively plasma cleaning the interior walls of at least one hollow body comprising the steps of: a) positioning said hollow body in the support of an apparatus according to any one of claims 1 to 12, b) create and maintain a predetermined level of pressure in said apparatus, c) introducing oxygen into the internal volume of said hollow body, d) creating a plasma discharge between the two said electrodes. 25 30 35