EP-4737409-A1 - DIGITAL GLAZE PRODUCTION PROCESS

Abstract

Digital glaze production process for particulate mixtures for ceramic glazes intended for high-discharge digital inkjet printing with a minimum resolution of 200 dpi, comprising a weighted dry ball mill (1) with a dynamic classifier (2) and a pneumatic homogenizer (3), characterized in that it comprises the steps of: dosing and feeding (4) the raw materials of the glaze components. milling the components in a weighted dry ball mill (1); where an induced airflow through the ball mill (1) drags the finer particles through a duct and directs them to a dynamic classifier (2) which redirects those particles larger than the required size back to the mill (1), and transport the finer particles to a receiving system (6) with a capacity between 1 to 100 ton at the outlet of the dynamic classifier (2), equipped with filters to avoid the particle flow to the vacuum pump (8), and integrated with a pneumatic homogenizer (3) capable of mixing the material contained in the receiving system (6), in partial or total capacity.

Inventors

• Villalba Balaguer, Maria Isabel

Assignees

• Mardiecar, S.L.

Dates

Publication Date

20260506

Application Date

20241104

Claims (3)

1. Digital glaze production process for particulate mixtures for ceramic glazes intended for high-discharge digital inkjet printing, comprising a dry ball mill (1) characterized in that it comprises the steps of: dosing and feeding (4) the raw materials of the glaze components; milling the components in a dry ball mill (1); where an induced airflow through the ball mill (1) drags the finer particles through a duct and directs them to a dynamic classifier (2) which redirects those particles larger than the required size back to the mill (1), and transport the finer particles to a receiving system (6) at the outlet of the dynamic classifier (2), equipped with filters (7) to avoid the particle flow to the vacuum pump (8) that induces the airflow, and integrated with a pneumatic homogenizer (3) for mixing the material contained in the receiving system (6).
2. Digital glaze production process, according to claim 1, where the ball mill (1) comprises a weighing system (5).
3. Digital glaze production process, according to claim 1, where the pneumatic homogenizer (3) comprises a system of discharge valves that allow complete emptying of the homogenized material.

Description

TECHNICAL SECTOR The present invention relates to a novel glaze production process, which allows the dry production of the glaze, improving its long-term quality. It is designed for obtaining a dry premix for high-discharge digital ceramic glazes. STATE OF THE ART The industrial production of tiles has traditionally involved the application of ceramic glazes as a coating, meeting functional protection requirements and providing aesthetic value to the product through shine, contrast and texture. The application of glazes to ceramic products is carried out industrially using different techniques such as a fluid curtain, screen printing, gravure, flexography and, more recently, through digital printing systems. This last technique presents the best performance since it enables the control of the application of the glaze and improves the efficiency in the use of material. However, it presents technical challenges given that digital injection poses specific requirements of granulometry and rheology to be viable. The application of digital glaze printing began in 2011 through the application of thin layers of material by the company Esmalglass-Itaca Grupo S.A in 2011. Later, new types of glazes that enabled their application in "high discharges" were developed, reaching levels between 100 and 200 g/m2 in one injection pass. Its characteristics and production processes are specified in the patents ES2386267B2 and ES2468553B1. Initially, digital glazes with particle sizes d95 < 1 µm were used, which implied high costs and high energy consumption in the production of such small particles. Later developments have allowed obtaining digital glazes with high grammages D100 < 40-65 µm as described in patents ES2489293B1 and ES2674978B1. These patents highlight that energy consumption is a critical point in the viability of high deposition digital glaze. On the other hand, the size of the particles that conform the glaze will determine the minimum diameter of the digital injectors to be used for its application, generally using injector diameters between 5-10 times the diameter of the maximum particle present in the glaze. It is well known that the resolution of the digital printing is inversely proportional to the diameter of the injectors. Thus, resolution will be greater if the diameter of the injectors is smaller. Depending on the characteristics of the desired final product, a balance is sought in the distribution of granulometry, so the requirements of resolution, rheology, deposition rate and specific energy consumption of the glaze production are complied. Given a specific particle size distribution in the glaze, the feasibility of its production depends on the overall production process, which incorporates factors such as equipment availability, suitability for continuous production, level of automation, cleaning requirements, among others. The production methodology for high-discharge digital glazes, according to patent ES2386267B2, consists of mixing solid raw materials, wet ball mill grinding (with water, solvents and additives) of those materials that make up the glaze. Then the particle size control of the material is controlled by screening and filtering at the mill discharge, and control and adjustment of viscosity. The final product is a liquid where the glaze particles are in suspension. The described production process sets out specifications that imply wet grinding and batch production, which requires the intervention of an operator to control the granulometry of the material present inside the mill. In this process, the material classification based on its size is carried out at the time of the batch discharge. These characteristics prevent production from being carried out in a continuous process and/or with low intervention of an operator, significantly constraining the potential for automation. The above-mentioned patents conceived the production of glaze that are dispatched as a ready to use mixture of the solid particles and a solvent agent. Although practical, this implies difficulties in preventing the settling of the particles and imposes an expiration time of the glaze. In this context, there is a need for an efficient production process for high-discharge digital glazes, based on an automatable circuit, capable of achieving continuous or high-volume batch production, with no or few stops required to measure the particle size, or for cleaning when changing materials. Additionally, the alternative of dispatching a dry mix of the glaze could prove practical if solid materials prone to settling are required in the glaze composition, and to avoid an expiration time for the product. The applicant does not know of any process or device similar to the invention, or which can be considered as a solution to the same technical problems. BRIEF EXPLANATION OF THE INVENTION The invention is a glaze production process. It allows for the creation of a ceramic glaze for digital printing with a very high reso