GLASS CONTAINER WITH A PROTECTIVE URETHANE ACRYLATE POLYMER COATING DEPOSITED ON AN OUTER SURFACE OF THE GLASS CONTAINER; METHOD OF PRODUCING SAID GLASS CONTAINER AND USE OF SAID GLASS CONTAINER

Abstract

A glass container comprising: an outer surface and an inner surface opposite the outer surface; and a urethane-acrylate polymer coating deposited on at least a portion of the outer surface, characterized in that the glass container has a lightness index L, calculated as =[weight of container(g) / (volume of container (mL))0.77]*0.44 of less than 1, preferably less than 0.90, more preferably less than 0.75 and more preferably less than 0.60.

Description

GLASS CONTAINER WITH A PROTECTIVE URETHANE-ACRYLATE POLYMER COATING DEPOSITED ON AN OUTER SURFACE OF THE GLASS CONTAINER; METHOD OF PRODUCING SAID GLASS CONTAINER AND USE OF SAID GLASS CONTAINER FIELD OF INVENTION The present invention relates generally to polymer-coated glass containers. More particularly, the present invention relates to glass containers coated with a urethane-acrylate polymer coating, especially beverage bottles, particularly non-returnable beverage bottles. BACKGROUND OF THE INVENTION Glass containers are widely used and reused in the packaging industry to package various contents, both liquid and solid, such as beverages, food, liquid and solid pharmaceuticals, water, and other substances. These packaged products are then transported over long distances for delivery to end consumers. During production, filling, and transport, glass containers can be scratched and damaged due to friction between them as they collide. Furthermore, the impact from collisions can also cause the containers to break. Additionally, the strength of returnable glass containers can be compromised by thermal shock, impact, and collisions. QAcnon / zznz / q / υιλι i BE2019 / 5903 among themselves. The packaging of contents in glass containers depends heavily on the mechanical strength of the glass, which is also affected by the processing techniques employed, including the speeds used in manufacturing and filling the glass containers; the handling equipment used; and / or impact from other containers. Mechanical damage to the glass container can include abrasion, scraping, and scratching of the glass surface. For returnable bottles, repeated chemical treatment for cleaning and refilling can also affect the quality of the glass, potentially reducing its lifespan. For example, treating returnable glass containers with a caustic bath damages the glass surface. Chemical and thermal treatments are also implemented to enhance the mechanical durability of the glass surface. Strengthening the surface of glass and glass bottles in general becomes even more critical for lightweight glass bottles. The growing focus on environmentally conscious industry is pushing the boundaries of material use, carbon footprint due to transportation, and overall sustainability. By reducing glass thickness to meet the demands of an environmentally conscious market, the sustainability of glass bottles is pushed to the limit, and glass strengthening becomes a prerequisite to prevent glass failure, thus jeopardizing the sustainability of glass bottles. Therefore, the market remains needing to provide lightweight glass bottles, particularly beverage bottles with coatings on their outer surfaces. QRcnan / zznz / q / uιλι QRcnon / zznz / q / uιλι BE2019 / 5903 of glass that positively influence the strength of the glass and protect the surface against scrapes and scratches, abrasion and failures. BRIEF DESCRIPTION OF THE INVENTION The present invention addresses the above market need based on the surprising finding that digitally printed urethane-acrylate polymer coatings enable lightweight containers without negatively impacting container sustainability. Therefore, it is an objective of the present invention to provide a glass container having a longitudinal axis, the container comprising: an outer surface and an inner surface opposite the outer surface; and a urethane-acrylate polymer coating deposited on at least a portion of the outer surface, characterized in that the glass container has a lightness index L, calculated as =[weight of container(g) / (volume of container (mL))°-77]*0.44 of less than 1, preferably less than 0.9, more preferably less than 0.75 and more preferably less than 0.60. Furthermore, it is an objective of the present invention to provide a method for coating a glass container having a longitudinal axis, the method comprising the steps of: - provide a glass container, the glass container is optionally coated with a hot-end coating; - depositing a urethane-acrylate polymer on at least part of an outer surface of the BE2019 / 5903 container using a digital printing technique; - curing the urethane-acrylate polymer deposited in the container to obtain a coating, characterized in that the glass container has a lightness index L, calculated as =[weight of container(g) / (volume of container (mL))°-77]*0.44 of less than 1, preferably less than 0.9, more preferably less than 0.75 and more preferably less than 0.60. It is an additional objective of the present invention to use a glass container as identified above or as produced by the above method as a container, preferably a bottle, for holding a beverage, preferably a carbonated beverage such as beer or cider. DETAILED DESCRIPTION OF THE INVENTION According to a preferred embodiment of the present invention, wherein the coating has a proportion T, where T is equal to ahhh ah h, which is measured along a theoretical line extending in a plane normal to the longitudinal axis of the container, on the circumference of the outer surface of the container, and where T has a maximum value of 0.062, preferably a maximum of 0.050, more preferably a maximum of 0.044. According to a first embodiment of the present invention, the glass container is a QRcnan / zznz / q / uιλι QAcnon / zznz / q / uιλι BE2019 / 5903 non-returnable bottle (one-way), preferably with an impact resistance of at least 70 cm / s, preferably at least 120 cm / s, preferably at least 210 cm / s and / or an internal pressure resistance of at least 1.2 MPa (12 bar), preferably at least 2 MPa (20 bar). According to a second embodiment of the present invention, the glass container is a returnable bottle, preferably with an impact resistance of at least 75 cm / s, preferably at least 120 cm / s, preferably at least 210 cm / s and / or an internal pressure resistance of at least 1.2 MPa (12 bar), preferably at least 2 MPa (20 bar). The glass container according to the present invention preferably has a urethane-acrylate polymer coating with an average thickness of between 20 and 40 µm, said urethane-acrylate polymer coating preferably defining an exposed outer contact area of ​​the container, which lacks an additional coating over the urethane-acrylate polymer coating. The urethane-acrylate polymer coating can be applied over a cold-end coating. The glass container is preferably a beverage bottle, more preferably a carbonated beverage bottle, more preferably a beer bottle or a cider bottle. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 illustrates a flowchart showing a method for coating a surface of BE2019 / 5903 glass of a glass container, according to an embodiment of the present invention. Figure 2 shows a glass bottle according to the present invention. DETAILED DESCRIPTION OF THE INVENTION The present invention provides a unique protective coating on a glass surface of a lightweight glass body to increase the glass's impact resistance. The coating also protects the glass surface from scratches and scrapes. In a preferred embodiment, the glass body is a glass container, particularly a glass bottle. According to the present invention, a preferred portion or the entire glass surface is coated with a urethane-acrylate polymer coating. A urethane-acrylate polymer coating has a very low coefficient of friction, is self-lubricating, and highly resistant to abrasion. Therefore, a urethane-acrylate polymer coating on a glass surface also protects it from abrasion, wear, and scratching, which are typically caused by friction resulting from the impact between two glass surfaces. Furthermore, because the urethane-acrylate polymer coating is self-lubricating, the glass surface is made slippery, preventing the two glass panes from sticking together and thus reducing friction. The glass container, preferably a beverage bottle, defines an interior space bounded by a portion of the body that extends along a longitudinal axis of the bottle and extends to one side, at a lower part, at a base of the bottle that extends at a lower part, the portion of the body extending on its other side, at a shoulder of the QAcnon / zznz / q / uιλι BE2019 / 5903 bottle, in a neck portion that extends to an opening in the bottle through which the interior space can be accessed for filling and emptying the bottle. In common glass bottle designs, the glass bottle has its largest diameter (measured perpendicular to the longitudinal axis) at the base and / or shoulder. According to the invention, the glass bottle has a lightness index L (as defined by the Japanese Glass Bottle Association), calculated as =[weight of bottle(g) / (volume of bottle (mL))077]*0.44 of less than 1, preferably less than 0.90, more preferably less than 0.75 and more preferably less than 0.60. Figure 1 provides a flow diagram showing a method for producing a glass container according to the present invention. As shown, the method comprises a step 102 of blowing a glass container defining an outer surface and an inner surface opposite the outer surface; a step 104 of cooling the glass container below the glass Tg; a step 106 of depositing a urethane-acrylate polymer onto at least a portion of an outer surface of the container using a digital printing technique; and a step 108 of curing the urethane-acrylate polymer deposited on the container to obtain a coating, the coating having a uniform thickness characterized by a ratio T, where T is equal to hh h, measured along a theoretical line extending in a plane normal to the longitudinal axis of the container on the circumference of the outer surface of the container, and where QRcnan / zznz / q / uιλι QRcnan / zznz / q / uιλι BE2019 / 5903 T has a maximum value of 0.062, preferably a maximum of 0.050, more preferably a maximum of 0.044. The container, preferably a glass bottle, thus produced can be a non-returnable (unidirectional) bottle or a returnable bottle on which the coating is applied with preferably an average thickness of between 20 and 40 pm. In the case of a one-way bottle, which is generally lightweight and designed to maintain functionality throughout the filling, transport, and consumption cycle, the coating allows for increased impact resistance to at least 70 cm / s, preferably at least 120 cm / s, and more preferably at least 210 cm / s, and / or increased internal pressure resistance to at least 1.2 MPa (12 bar), preferably at least 2 MPa (20 bar). This is particularly suitable for bottles used to contain carbonated beverages such as beer. In the case of returnable bottles, which are designed to remain functional for six or more cycles of filling, transport, consumption, and cleaning, the coating allows for increased impact resistance to at least 70 cm / s, preferably at least 120 cm / s, and more preferably at least 210 cm / s, and / or increased internal pressure resistance to at least 1.2 MPa (12 bar), preferably at least 2 MPa (20 bar). Again, this is particularly suitable for bottles used to contain carbonated beverages such as beer. Regardless of the type of container or, in particular, the bottle, the volume it will contain should preferably range between 10 cL and 1.2 L. QRcnan / zznz / q / uιλι BE2019 / 5903 Acrylate-urethane coating Urethane-acrylates are generally prepared from isocyanates, polyols, and acrylates. Examples of isocyanates include hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, toluene diisocyanate, isophorone diisocyanate, phenyl isocyanate, naphthyl isocyanate, and similar compounds. Examples of polyols include polyether polyol, polyester polyol, acryl polyol, polysiloxane polyol, and similar compounds. Examples of polyester polyols include polyethylene glycol, polypropylene glycol, polyols composed of a copolymer of ethylene oxide and propylene oxide, polytetramethylene glycol, and similar compounds. Examples of polyester polyols include caprolactone polyol, polycarbonate polyol, and similar compounds. Acrylate is preferably one that has a hydroxyl group and one or more acrylic groups. Examples of hydroxyacrylates with a single acrylic group include hydroxyethyl acrylate, hydroxyacyl(meth)acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, and the like. Examples of hydroxyacrylates with multiple (preferably two or more and four or fewer) acrylic groups include pentaerythritol triacrylate and the like. To obtain urethane-acrylate having a plurality of acrylic groups on at least one side of the main chain terminal, it is preferable to use hydroxyacrylate having a plurality of acrylate groups. Digital printing of the urethane coating allows for better control over coating thickness and uniformity compared to other application techniques such as screen printing or spraying. This improved control results in a coating that is BE2019 / 5903 is less prone to surface effects and is believed to be more environmentally friendly in terms of material use and energy consumption for application and curing. Impact resistance test method Typically, impacts are performed at the point of contact for that particular item, such as the rim and base of a bottle or the edge of a beer glass, and the test is carried out until the sample fails. However, customer requests can also be accommodated, such as testing until the first damage is visible or at specific impact positions. For the present invention, the values ​​provided in this specification are measured at the shoulder of the bottle using an industry-standard, calibrated AGR and UKAS impact device accredited according to ISO 17025. Example A glass bottle, as shown in Figure 2, was coated using a method according to the present invention. The coating thickness was then measured at 12 equidistant points along a theoretical line extending around the circumference of the bottle's outer surface in a plane normal to the bottle's longitudinal axis. This measurement was repeated to collect data from three theoretical lines on the bottle's shoulder and three theoretical lines on the bottle's base. The results are shown in Table 1 below. QRcnon / zznz / q / uιλι BE2019 / 5903 QRcnon / zznz / q / uιλι Shoulder Position (gm) 0° 30° 60° 90° 120° 150° 180° 210° 240° 270° 300° 330 AVG SD SD / AVG Measurement of location in the image 1 27 26 27 28 28 30 28 26 28 27 27 27 27.417 1.084 0.040 2 28 27 29 30 29 25 30 28 26 28 28 25 27.750 1.712 0.062 3 26 29 28 29 29 28 30 28 28 28 30 27 28.333 1.155 0.041 Base Position (gm) 0° 30° 60° 90° 120° 150° 180° 210° 240° 270° 300° 330 AVG SD SD / AVG Location measurement in the image 1 25 28 24 26 27 27 25 26 25 26 26 27 26.000 1.128 0.043 2 25 26 26 25 26 26 25 24 26 26 27 25 25.583 0.793 0.031 3 25 27 25 28 28 27 26 27 27 27 25 25 26.417 1.65 0.044 Table 1

Claims

1. A glass container comprising: an outer surface and an inner surface opposite the outer surface; and 5 a urethane-acrylate polymer coating deposited at least on a portion of the outer surface, characterized in that the glass container has a lightness index L, calculated as =[weight of container(g) / (volume of container (mL))°-77]*0.44 of less than 1, preferably less than 0.90, more preferably less than 0.75 and more preferably less than 0.

60.

2. The glass container according to claim 1, wherein the coating is characterized by a ratio T, where T is equal to the sample standard deviation of the coating thickness, which is measured along a theoretical line extending in a plane normal to the longitudinal axis 15 of the container on the circumference of the outer surface of the container, having a value of maximum 0.062, preferably maximum 0.050, more preferably maximum 0.

044.

3. The glass container according to claim 1 or 2, wherein the container QAcnon / zznz / q / uili BE2019 / 5903 has an internal pressure resistance of at least 1.2 MPa (12 bar), preferably at least 2 MPa (20 bar).

4. The glass container according to any of the preceding claims, wherein it has an impact resistance of 70 cm / s, preferably 120 cm / s, 5 preferably 210 cm / s.

5. The glass container according to any of the preceding claims, wherein it has an internal volume of between 10 cL and 1.2 L.

6. The glass container according to any of the preceding claims, wherein the urethane-acrylate polymer coating has an average thickness of between 20 and 40 pm.

7. The glass container according to any of the preceding claims, wherein the urethane-acrylate polymer coating defines an exposed outer contact area of ​​the container, which lacks an additional coating over the urethane-acrylate polymer coating. 15 8. The glass container according to any of the preceding claims, wherein the urethane-acrylate polymer coating is applied over a hot-end coating. QAcnan / zznz / q / uili BE2019 / 5903 9. The glass container according to any of the preceding claims, wherein the container is a beverage bottle, preferably a carbonated beverage bottle.

10. The glass container according to claim 9, wherein the bottle is a 5 beer or cider bottle.

11. The glass container according to any of the preceding claims, wherein the glass container is a returnable or non-returnable glass bottle.

12. The method of coating a glass container having a longitudinal axis, the method comprising the steps of: - providing a glass container, the glass container being optionally coated with a hot-end coating; - depositing a urethane-acrylate polymer on at least a portion of an outer surface of the container by means of a digital printing technique; - curing the urethane-acrylate polymer deposited on the container to obtain a coating, characterized in that the glass container has a lightness index L, calculated as =[weight of container(g) / (volume of container (mL))°-77]*0.44 QRcnan / zznz / q / υιλι ΒΕ2019 / 5903 of less than 1, preferably less than 0.90, more preferably less than 0.75 and more preferably less than 0.

60.

13. The method according to claim 1, wherein the coating is characterized by a ratio T, where T is equal to 5 standard deviations of the coating thickness, - which is measured along a theoretical line extending in a plane normal to the longitudinal axis of the container, on the circumference of the outer surface of the container has a value of maximum 0.062, preferably maximum 0.050, more preferably maximum 0.

044.

14. Use of a glass bottle according to any of claims 1 to 10, for containing a beverage, preferably a carbonated beverage.

15. Use of a glass container according to any of claims 1 to 10, for holding beer or cider.

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