EP4034509A1

EP4034509A1 - Method for decoratively marking glass articles at high temperature by laser

Info

Publication number: EP4034509A1
Application number: EP20796860.3A
Authority: EP
Inventors: Frédéric Dupuis; Faurie MADDLY
Original assignee: Saverglass SAS
Current assignee: Saverglass SAS
Priority date: 2019-09-26
Filing date: 2020-09-25
Publication date: 2022-08-03
Also published as: WO2021058925A1; US20220402816A1

Abstract

The invention relates to a method for manufacturing a hollow glass article (8) comprising a step of marking the hollow glass article thus formed by laser (6), the surface of the hollow glass article being at a temperature of between 400°C and 600°C. The marking step consists in making filiform decorations by producing at least one continuous, shiny groove on the surface of the hollow glass article.

Description

Title: PROCESS FOR MARKING A DECORATIVE PURPOSE OF GLASS ARTICLES AT HIGH TEMPERATURE BY LASER

The invention relates to the field of decoration, personalization, and marking of glass articles, preferably hollow glass articles.

[0002] The production of a relief on the surface of the glass is a known decoration technique which can be implemented in different ways such as, for example, etching by mechanical size, forming by molding or even etching by acid treatment.

[0003] Size engraving consists of mechanically modifying the surface appearance using engraving tools (silicon carbide tip, tungsten carbide, diamond grinding wheel, etc.) which hollow out the glass on the surface. The decorating operation is usually manual, but can be automated. When this is automated, it requires the implementation of particularly expensive processes (pruning machine, robotic system). This process is therefore particularly suitable for products with very high added value (decanters, centerpieces, stemmed glasses and crystal goblets, for example) or for the personalization of objects. Since the etching obtained directly by this process has a matte appearance, obtaining an etching with a glossy appearance requires additional acid or mechanical polishing operations.

[0004] Sandblasting etching can also be used, a mask is first applied to the surfaces of the glass article to be protected and then sand is sprayed under pressure in order to locally and mechanically attack the surface of the unprotected glass. The etching obtained has a more or less whitish and more or less matt appearance depending on the particle size distribution and the geometry of the projected sand. However, this etching process does not make it possible to achieve brilliant etching and the definition of the patterns remains limited.

[0005] Acid etching can also be implemented. This process also requires the deposition of a mask on the surfaces to be protected. prior to the etching step. The article is then immersed in baths of aggressive chemical compositions to obtain glossy, matt or satin engravings. The result obtained by such a process will depend on the nature of the baths, their level of agitation, the immersion times of the article and the combination of different soaks. Such a process uses extremely dangerous concentrated products (hydrofluoric acid, possibly combined with sulfuric or hydrochloric acid and ammonium bifluoride to obtain satin or matt appearances) and produces significant quantities of effluents (emissions toxic carbonated gases and acidic rinsing water which must be treated), even for engraving thicknesses of a few hundred microns. This process also generates large volumes of waste (sludge from the chemical neutralization of acidic rinsing water) which must be recycled in external channels. Consequently, this method proves to be extremely expensive.

It is also possible to modify the surface of a glass article during the forming process thanks to the structure of the forming mold. The appearance of the etching on the glass depends on the quality of the mold and the parameters of the forming. The disadvantages of this process are numerous. In fact, mold release problems can first of all be encountered if the temperatures of the glass and of the molds are not perfectly controlled. It is also very difficult to produce very fine reproducible patterns, the molds wearing out and clogging very quickly (with the residues of mineral release grease, generally loaded with graphite, or graphite. In addition, each engraved decoration in molds requiring a more or less pronounced draft depending on the height of the targeted relief decoration, this limits the fineness of the engraving. The proximity between the patterns and the mold joints can also hinder the release of the articles and generate glazes (360 ° decorations on the body of articles are often difficult or even impossible to achieve) without an arrangement of the engraving at the level of the mold joints. The technical feasibility of such a process and / or its financial viability is thus often questioned if the production volumes are not large enough. An object of the present invention is to respond to the drawbacks of the prior art mentioned above and in particular to be able to engrave fine and shiny patterns for decoration and personalization.

[0008] More particularly, the present invention therefore relates to a method of manufacturing a hollow glass article comprising the following steps:

- hot forming of the hollow glass article by means of a forming machine,

- marking of the hollow glass article thus formed by laser, the surface of the hollow glass article being at a temperature between 400 ° C and 600 ° C, and

- annealing of the hollow glass article thus marked in an annealing arch; said manufacturing method being characterized in that the marking step consists in producing filiform decorations by producing at least one continuous and shiny groove on the surface of the hollow glass article, the groove being defined by a line single, and in that, prior to the marking step, the manufacturing process further comprises a laser adjustment step consisting in adjusting the laser using:

- a first parameter which is the definition factor, so that the latter is greater than 2.5, the definition factor being defined as the ratio of the product of the diameter of the laser spot (6) with the frequency of the laser (6) and the scanning speed of the laser (6), and

- a second parameter which is the surface energy, so that the latter is greater than or equal to 0.65J / mm2, the surface energy being defined as the ratio of the product of the energy of a laser pulse with the frequency of the laser (6) and the product of the diameter of the laser spot (6) with the scanning speed of the laser (6).

Thanks to the invention, it is possible to make engravings on the surface of hollow glass articles with a laser. The laser is placed at the exit of the forming machine, before the annealing arch of the glass articles. In this zone, the glass constituting the hollow glass article is still sufficiently malleable so that the energy supplied by the laser can mark the surface of the hollow glass article in order to reveal a relief engraving, visible to the eye. naked eye and shiny. Advantageously, the laser has a wavelength of which the absorption rate by the surface of the hollow glass article is greater than 80%, preferably greater than 90%.

Advantageously, the step of adjusting the laser consists in adjusting the laser so that the surface energy is greater than or equal to 0.80J / mm ² .

[0012] According to other features of the invention, the hollow glass article is made of soda-lime glass. The hollow glass article may be crystal, or crystalline, or borosilicate or fluorosilicate glass.

Advantageously, the method for performing the step of marking the hollow glass article is based on the use of a CO2 type laser. The light energy resulting from the wavelength (10.6mm) of such a laser will then be 90% absorbed by the glass, thus causing at least one continuous groove on the surface of the hollow glass article.

According to a first embodiment of the invention, the hollow glass article is placed on a conveyor circulating from the forming step to the annealing step. The step of marking the hollow glass article is therefore carried out on the conveyor and the glass is thus engraved directly on the production line.

According to a second embodiment, the method of manufacturing the hollow glass article comprises a step of transferring the hollow glass article from the conveyor onto an ancillary equipment, the marking step being carried out on said equipment. Annex.

[0016] Following the marking step, the hollow glass article returns to its place on the main conveyor. The step of transferring the hollow glass item from the production line to the ancillary equipment thus increases the time dedicated to carrying out the marking step and allows for a more complex decoration.

Advantageously, the ancillary equipment comprises a carousel.

The object of the present invention also relates to a hollow glass article obtainable by the manufacturing process as defined according to any one of the preceding characteristics. Advantageously, the hollow glass article comprises at least one continuous and shiny groove produced by the laser on the surface of the hollow glass article having a depth of between 25 mm and 30 mm, a width of between 300 to 450mm and two beads with a height of between 5 and 7mm. These characteristics of the continuous groove make it possible to obtain a visible marking.

Other characteristics and advantages of the present invention will emerge more clearly on reading the detailed description which follows for the understanding of which reference is made to the accompanying drawings, in which:

[0021] [Fig. 1] - Figure 1 is a diagram of a production line of the manufacturing process of a hollow glass article according to a first embodiment of the invention, the diagram illustrating different possible locations of the area dedicated to the step of decorative marking of the hollow glass article;

[0022] [Fig. 2] - Figure 2 is a diagram of a production line of the manufacturing process of a hollow glass article comprising a carousel according to a second embodiment of the invention, the diagram illustrating different possible locations of the dedicated area at the step of marking the hollow glass article;

[0023] [Fig. 3] - figure 3 shows an image obtained with a binocular magnifying glass of a marking on a hollow glass article produced by a laser whose definition factor is 0.5 and the surface energy is 0.3J / mm ² (see example 1);

[0024] [Fig. 4] - figure 4 shows an image obtained with a binocular magnifying glass of a marking on a hollow glass article produced by a laser whose definition factor is 5 and the surface energy is 1.1 J / mm ² (see example 1);

[0025] [Fig. 5] - Figure 5 shows an image obtained with a binocular magnifying glass of a marking on a hollow glass article produced by a laser, the surface to be treated being placed at the focal plane of the laser (see example 2);

[0026] [Fig. 6] - figure 6 shows an image obtained with a binocular magnifying glass of a marking on a hollow glass article produced by a laser, the surface to be treated being placed at a distance of 10 mm from the focal plane of the laser (see example 2);

[0027] [Fig. 7] - figure 7 shows an image obtained with a binocular magnifying glass of a marking on a hollow glass article produced by a laser, the surface to process being placed at a distance of 12mm from the focal plane of the laser (see example 2);

[0028] [Fig. 8] - Figure 8 is a schematic perspective view of the laser marking space in the area dedicated to the step of marking a hollow glass article by laser (see Example 3);

[0029] [Fig. 9] - Figure 9 is a schematic view of the area dedicated to the step of marking a hollow glass article by laser comprising a cylindrical hollow glass article positioned to be marked by the laser (see Example 3);

[0030] [Fig. 10] - Figure 10 is a view similar to that of Figure 9 in which the hollow glass article ready to be marked is square (see example 3);

[0031] [Fig. 11] - Figure 11 is a sectional view of a groove on a hollow glass article obtained by the laser marking step (see Example 4);

[0032] [Fig. 12] - Figure 12 is a front view of a hollow glass article obtainable by the manufacturing process according to the invention (see Example 4).

Figures 1 and 2 show two distinct embodiments of the present invention. These figures are commented on below, while Figures 3 to 11 are detailed in the examples which follow.

According to the two embodiments illustrated in Figures 1 and 2, the production line successively comprises:

- a forming machine 1 dedicated to the hot forming step of the hollow glass article 8,

- a heat treatment hood 2 of the hollow glass article 8 thus formed,

- a first zone 3 dedicated to the Datamatrix marking step,

- a transfer wheel 5, and

- an annealing arch 4 dedicated to the annealing step of the hollow glass article 8.

Each hollow glass article 8 is arranged on a conveyor 9 from the forming step to the annealing step. The conveyor 9 is provided for conveying the hollow glass articles 8 from one area to another on the production line. According to the first embodiment illustrated in Figure 1, the decorative laser marking step is performed directly on the production line, at the output of forming machine 1, in a second zone 60 dedicated to the step decorative laser marking.

The second zone 60 dedicated to the decorative laser marking step can be positioned in four different locations:

1.before the heat treatment hood 2,

2.between said hood 2 and the first zone 3 dedicated to the Datamatrix marking step,

3.before the transfer wheel 5, or

4.after the transfer wheel 5.

In this first embodiment, the decorative marking step consists in decorating all the hollow glass articles 8 produced during the hot forming step and moving on the conveyor 9 of the forming machine 1.

In addition, it is possible to provide several lasers 6 around the hollow glass article 8 in order to mark different faces of the hollow glass article 8 simultaneously.

[0040] Therefore, the time allocated to the marking step is dictated by the production rate established on the production line. This may restrict the possible surface to be decorated, i.e. the extent of the engraving, depending on the space available to implant the lasers 6 and the capacity of the latter (in terms of power and scanning speed).

According to a second embodiment of the invention illustrated in Figure 2, the manufacturing process comprises ancillary equipment and more particularly a carousel 7.

The decorative laser marking step is here performed outside the production line, on the ancillary equipment, here the carousel 7. The second zone 60 dedicated to the decorative laser marking step is therefore arranged on the carousel 7, it can be positioned in three different locations:

1.before the heat treatment hood 2,

2.between said heat treatment hood 2 and the first zone 3 dedicated to the Datamatrix marking step, or 3.before the transfer wheel 5.

[0043] In Figure 2, the second zone 60 dedicated to the decorative laser marking step is positioned between the heat treatment hood 2 and the first zone 3 dedicated to the Datamatrix marking step. The other two possible arrangements of the second zone 60 dedicated to the decorative laser marking step are shown diagrammatically by dotted squares.

According to this second embodiment, the manufacturing process comprises the following steps:

- hot forming of the hollow glass article by means of a forming machine 1,

- linear scrolling of the hollow glass articles 8 on the conveyor 9,

- transfer of the hollow glass article 8 from the conveyor 9 to the ancillary equipment,

- marking of the hollow glass article 8 by laser, and

- transfer of the hollow glass article 8 thus marked from the carousel 7 to the conveyor 9.

In this second embodiment, all or part of the hollow glass articles 8 from the forming machine 1, the surface of which is at a temperature between 400 ° C and 600 ° C, are transferred automatically on ancillary equipment. Therefore, the decorative laser marking step 6 is said to be deported.

The step of transferring the hollow glass article 8 from the production line to the ancillary equipment thus makes it possible to increase the time dedicated to carrying out the decorative marking step and to achieve a more decor. complex. It also makes it possible to extend the decorated surface while using several lasers 6 of reasonable power.

The ancillary equipment may for example be designed to select a hollow glass article 8 out of n present on the conveyor 9, for example n is equal to three.

According to an exemplary embodiment of the invention, the transfer of the hollow glass article 8 from the conveyor 9 to the ancillary equipment and vice versa is effected by taking the hollow glass article 8 by the ring thus allowing not damage the marking on the body, shoulder or neck of the hollow glass article 8.

During the marking step, the hollow glass article 8 is indexed by an optical or mechanical detection system via a mechanism provided to perform the alignment of the hollow glass article 8 with the laser (s) (s) 6.

[0050] The ancillary equipment can be fixed or rotate during the marking step. The hollow glass articles 8 can therefore be rotated in front of one or more laser (s) 6, thus facilitating the 360 ° decoration operations.

It is therefore possible to provide several marking stations around the hollow glass article 8 in order to mark different faces of the hollow glass article 8 simultaneously. For this, these marking stations are arranged on the same ancillary equipment and are supplied either by a single laser source or by several laser sources.

In the case of rotating ancillary equipment; the rotation of the hollow glass article 8 is controlled by the laser process 6. The rotation of the ancillary equipment can be continuous or discontinuous and the speed of rotation can be variable or constant.

[0053] In addition, the ancillary equipment is suitable for limiting thermal and mechanical shocks.

The method of processing hollow glass articles 8 via ancillary equipment such as a carousel 7 proves to be more complete and complex than the method of processing carried out directly on the production line.

The advantages of using ancillary equipment for carrying out the step of decorative marking of hollow glass articles 8 are:

- the treatment of part of the hollow glass articles 8 products (1 glass article out of 2, out of 3 out of 4 ...) allows to benefit from a longer exposure time, therefore to achieve marking surfaces more consequent: we partially free ourselves from the production rates,

the rotation of the hollow glass article 8 offers the possibility of decorating the hollow glass article 8 over its entire periphery,

- the adjustment of the distance between the surface to be treated of the hollow glass article 8 and the lens makes it possible to increase the surfaces available for laser marking (we are less limited by the depth of field of the laser),

- the rotation system allows the marking of 8 cylindrical hollow glass articles by managing the presence of the two mold seals,

- simultaneous marking of several areas of the hollow glass article 8, or even 360 °, and

- the realization of a fine and shiny engraving not achievable by the hot forming step, and without the need to take back the hollow glass article 8.

However, the implementation of these different processing modes require specific settings:

- perfect synchronization with the forming machine 1 in order to ensure the transfer of the hollow glass article 8 from the conveyor 9 to the ancillary equipment,

- perfect synchronization between the position of the hollow glass article 8 on the ancillary equipment, its orientation and the triggering of the laser pulses,

- the use of materials suitable for handling hot glass, and

- protection of the laser system from nearby heat sources.

A varioscan can also be used in this embodiment: The position of each hollow glass article 8 is determined by means of a position sensor and the focal length of the laser 6 is automatically adjusted to the position of this article.

The following examples illustrate the marking step of the method of manufacturing a hollow glass article 8 according to the invention, based on Figures 3 to 11.

EXAMPLES

EXAMPLE 1 Adjustment of the physical parameters of the laser 6

Several parameters have been taken into account for the realization of a qualitative laser marking on the hollow glass article 8 such as the power, the frequency and the scanning speed of the laser beam 6. The optimal parameters have were determined experimentally, first by visual assessment, then, using a binocular magnifying glass. They were then translated under the form of physical parameters such as the energy received by the surface of the treated glass, the definition factor of the engraving, the energy of a laser pulse, etc.

Two physical parameters have been defined to digitally characterize the marking:

- the surface energy: its value makes it possible to determine whether the surface of the hollow glass article 8 will be sufficiently marked or not,

- the definition factor: its value makes it possible to determine whether the mark made on the surface of the hollow glass article 8 is continuous or not. This value depends on the spot size, the scanning speed and the frequency of the laser 6.

The surface energy (J / mm ² ) is defined as follows:

[0063] [Math. 1]

[0064] With:

- the energy of a laser pulse in mJ,

- the frequency of the laser in Hz,

- the diameter of the laser spot in microns,

- the scanning speed of the laser 6 in mm / s.

The definition factor promotes the sharpness of the decorations produced and gives information on the level of overlap of the impacts produced by the laser on the surface of the hollow glass articles 8. If the definition factor is very low, it is that is to say less than 1, the groove produced on the surface of the hollow glass articles 8 by the laser 6 proves to be insufficiently smoothed and even discontinuous. Experience shows that this definition factor must be greater than or equal to 2.5 to obtain a well-defined decor.

The definition factor is obtained with the following formula:

[0067] [Math. 2]

Decor definition factor

[0068] With:

- the diameter of the laser spot in microns, - the frequency of laser 6 in Hz,

- the scanning speed of the laser 6 in mm / s.

The table below illustrates some results of etchings obtained on the surface of hollow glass articles 8 whose temperature is between 450 and 550 ° C. The experiments were carried out with a lens of 250mm focal length, a 125W CO2 laser, a beam diameter of 14mm (before focusing) and different values for each physical parameter, thus making it possible to obtain more or less qualitative engravings.

[0070] [Table 1]

These various experiments prove that to obtain a correct marking on the hollow glass article, that is to say sufficiently marked and continuous, the value of the surface energy must be at least equal to 0.65 J / mm ² and preferably at least equal to 0.80J / mm ² , and the value of the definition factor must be strictly greater than 2.5.

The importance of adjusting the definition factor and the surface energy of laser 6 is also illustrated in Figures 3 and 4.

FIG. 3 shows an image obtained with a binocular magnifying glass of a marking whose definition factor is 0.5 and the surface energy is 0.3J / mm ² . The marking obtained is discontinuous and shallow, which gives an unattractive appearance to the engraving. Figure 4 shows an image obtained with a binocular magnifying glass of a marking on a hollow glass article 8 produced by a laser 6 whose definition factor is 5 and the surface energy is 1.1J / mm2 . The marking obtained is then of quality.

Consequently, the two physical parameters of the laser 6, that is to say the surface energy and the definition factor, are complementary and for obtaining an aesthetic and qualitatively satisfactory engraving, it is essential that both conditions are met.

For the sake of productivity, it is essential that the scanning speeds of the laser beam be as high as possible, a speed greater than 1000 mm / s generally proving to be required for the production of extended filiform decorations on the surface of the hollow glass article 8. It is therefore important to choose a sufficient power of the laser 6 and sufficiently close pulses to obtain a satisfactory definition factor.

EXAMPLE 2 Adjustment of the distance between the surface to be treated and the focal plane of the laser 6

Figures 5 to 7 show the quality of the marking as a function of the distance between the lens and the surface to be treated for a glass temperature of between 400 ° C and 600 ° C. The depth of the marking directly impacts the final rendering of the engraving on the hollow glass article 8.

FIG. 5 shows an image obtained with a binocular magnifying glass of a marking on a hollow glass article 8 produced by a laser 6, the surface to be treated being placed at the level of the focal plane of the laser 6.

Figure 6 shows an image obtained with a binocular magnifying glass of a marking on a hollow glass article 8 produced by a laser 6, the surface to be treated being placed at a distance of 10mm from the focal plane of the laser 6 .

Figure 7 shows an image obtained with a binocular magnifying glass of a marking on a hollow glass article 8 produced by a laser 6, the surface to be treated being placed at a distance of 12mm from the focal plane of the laser 6 . The laser marking results presented in Figures 5 and 6 are qualitatively satisfactory unlike the result presented in Figure 7 which is not satisfactory.

[0083] Therefore, to obtain an aesthetic and quality engraving, the distance between the surface to be treated and the focal plane of the laser 6 must be less than or equal to 10mm.

EXAMPLE 3: Laser marking space 6 and positioning of the surface to be treated of the hollow glass article 8.

[0085] For example, an Ftheta laser lens with a focal length of 250mm allows for a plane field of fire of 170mm x 170mm and a depth of field of the order of 20mm. The complete system allows for a theoretical spot diameter at the focal plane of laser 6 of 310mm. The actual diameter of the impacts on the glass will depend on the adjustment parameters of the laser 6, the temperature of the surface of the glass, and the lens / surface distance.

FIG. 8 illustrates the laser marking space 6 in the area dedicated to the marking step, on the conveyor 9, in which the laser marking obtained is satisfactory. It has been experimentally demonstrated that the result of the labeling is homogeneous in a thus extended labeling space (170mm x 170mm x 20mm).

Such a marking space makes it possible to envisage homogeneous decorations on more or less complex surfaces moving on a conveyor 9 and brought to a temperature of between 400 ° C and 600 ° C. This temperature range is valid for soda-lime, crystal, crystalline, borosilicate or fluorosilicate type glasses.

Figures 9 and 10 illustrate the optimal position of a hollow glass article 8 relative to the laser 6 during the marking step. The hollow glass article 8 is arranged in the area dedicated to the marking step, on the conveyor 9, the laser 6 defining a marking space (rectangular) as shown in FIG. 8 and the focal plane of the laser 6 being in the middle of the marking space. The surface to be treated by the laser 6 of the hollow glass article 8 being the surface coinciding with the marking space of the laser 6. Preferably, as can be seen in Figures 9 and 10, the hollow glass article 8 is positioned so that the focal plane of the laser 6 is in the middle of the surface to be treated by the laser 6 of the hollow glass article 8, depending on the depth of the laser marking space 6.

EXAMPLE 4 Obtaining at least one continuous groove produced by the laser 6

In order to characterize the markings, profile measurements were carried out on a chromatic confocal optical bench. Figure 11 is a sectional view of a groove on a hollow glass article 8 obtained by the laser marking step, the groove being defined as a single line.

The parameters which characterize the quality of the laser marking (shown in Figure 11) are the depth of the groove (b) produced by the laser 6, the width of the groove (c) produced on the surface of the glass article hollow 8, and the height of the two beads (a).

A qualitative marking is characterized by a groove depth of between 25 and 30 miti, a groove width of 300 to 450 mm on the surface of the hollow glass article 8 and a bead height of between 5 and 7mm .

[0094] Figure 12 is a front view of a hollow glass article obtainable by the manufacturing process according to the invention. The hollow glass article 8 of Figure 12 has threadlike decorations formed by a plurality of continuous grooves produced on the surface of the hollow glass article 8 during the marking step.

It is of course possible to combine this decorative marking process with decoration techniques already known and capable of covering, in whole or in part, the engravings previously produced according to the invention, that is to say the metallization or the 'surface iridescence by CVD process, the deposition of precious metals by screen printing and the application of varnishes and shiny, satin, pearlescent and metallized lacquers.

Claims

[Claim 1] A method of manufacturing a hollow glass article (8) comprising the following steps:

- hot forming of the hollow glass article (8) by means of a forming machine (1),

- marking of the hollow glass article (8) thus formed by laser (6), the surface of the hollow glass article (8) being at a temperature between 400 ° C and 600 ° C, and

- annealing of the hollow glass article (8) thus marked in an annealing arch (4); characterized: in that the marking step consists of producing filiform decorations by producing at least one continuous and shiny groove on the surface of the hollow glass article (8), the groove being defined by a single line , and in that, prior to the marking step, the manufacturing method further comprises a step of adjusting the laser (6) consisting in adjusting the laser (6) using:

[Claim 2] The manufacturing method according to claim 1, characterized in that the laser (6) has a wavelength of which the absorption rate by the surface of the hollow glass article (8) is greater than 80 %.

[Claim 3] The manufacturing method according to any one of the preceding claims, characterized in that the step of adjusting the laser (6) consists in adjusting the laser (6) so that the surface energy is greater than or equal to 0.80J / mm ² .

[Claim 4] The manufacturing method according to any one of the preceding claims, characterized in that the hollow glass article (8) is made of soda lime glass.

[Claim 5] The manufacturing method according to any one of claims 1 to 3, characterized in that the hollow glass article (8) is made of crystal, or crystalline, or borosilicate or fluorosilicate glass.

[Claim 6] The manufacturing method according to claim 2, characterized in that the absorption rate of the wavelength of the laser (6) by the surface of the hollow glass article (8) is greater than 90%. .

[Claim 7] The manufacturing method according to any one of the preceding claims, characterized in that the laser (6) is a CO2 laser.

[Claim 8] The manufacturing method according to any one of the preceding claims, characterized in that the hollow glass article (8) is placed on a conveyor (9) circulating from the forming step to the step. annealing.

[Claim 9] The manufacturing method according to claim 8, characterized in that prior to the step of marking the hollow glass article (8), the manufacturing process comprises a step of transferring the hollow glass article. (8) of the conveyor (9) on ancillary equipment, and in that the marking step is carried out on said ancillary equipment.

[Claim 10] The manufacturing method according to claim 9, characterized in that the ancillary equipment comprises a carousel (7).

[Claim 11] A hollow glass article (8) obtainable by the manufacturing process as defined in any one of the preceding claims.

[Claim 12] The hollow glass article (8) according to claim 11, characterized in that the continuous and shining furrow produced by the laser (6) on the surface of the hollow glass article (8) has a depth between 25 and 30 mm, a width of between 300 to 450mm and two beads with a height of between 5 and 7mm.