Abstract: A device for measuring the level in a reservoir of an inkjet printer, comprising: an electrode, which has a first end and an second end, and which is covered from the first end up to an intermediate level between the first end and the second end, with an electrically insulating coating, where the electrode has capacitive behavior for a level of liquid between the first end and the intermediate level, and resistive behavior beyond this, circuit for measuring a signal which is characteristic of capacitive behavior of the device, for a liquid level between the first end and the intermediate level, and for identifying resistive behavior of the device for a level of the liquid above the intermediate level, circuit for estimating or calculating, from the characteristic signal, a height of the liquid contained in the reservoir, for a liquid level between the first end and the intermediate level.

Abstract: The invention relates to a method for controlling the ink quality of an ink jet printer, during printing, the printer comprising at least one ink reservoir (11) and a solvent or diluted ink reservoir (12), a print head (50) and a supply circuit for sending ink and/or solvent to the print head, method in which: a correction volume of solvent, or diluted ink, to add to the ink to compensate a variation in viscosity of the latter is estimated; and a plurality of elementary quantities of solvent, or diluted ink, separated by ink, is sent to the print head, each of a volume comprised between 0.1 cm3 and 5 cm3, the sum of the elementary quantities of solvent, or diluted ink, being substantially equal to the correction volume to add.

Abstract: The invention relates to a method for controlling the ink quality of an ink jet printer, during printing, the printer comprising at least one ink reservoir (11) and a solvent or diluted ink reservoir (12), a print head (50) and a supply circuit for sending ink and/or solvent to the print head, method in which: a correction volume of solvent, or diluted ink, to add to the ink to compensate a variation in viscosity of the latter is estimated; and a plurality of elementary quantities of solvent, or diluted ink, separated by ink, is sent to the print head, each of a volume comprised between 0.1 cm3 and 5 cm3, the sum of the elementary quantities of solvent, or diluted ink, being substantially equal to the correction volume to add.

Abstract: A device for measuring the level in a reservoir of an inkjet printer, comprising: an electrode, which has a first end and an second end, and which is covered from the first end up to an intermediate level between the first end and the second end, with an electrically insulating coating, where the electrode has capacitive behaviour for a level of liquid between the first end and the intermediate level, and resistive behaviour beyond this, circuit for measuring a signal which is characteristic of capacitive behaviour of the device, for a liquid level between the first end and the intermediate level, and for identifying resistive behaviour of the device for a level of the liquid above the intermediate level, circuit for estimating or calculating, from the characteristic signal, a height of the liquid contained in the reservoir, for a liquid level between the first end and the intermediate level.

Abstract: A method for printing an authentication pattern wherein, using a multi-deflection continuous inkjet printer, the pattern is printed on a substrate and only contains a small number of black pixels per raster. The resolution in the travel direction X of the substrate and in direction Y of the rasters is thereby largely improved compared with printing in dot-matrix mode.

Abstract: A method for printing an authentication pattern wherein, using a multi-deflection continuous inkjet printer, the pattern is printed on a substrate and only contains a small number of black pixels per raster. The resolution in the travel direction X of the substrate and in direction Y of the rasters is thereby largely improved compared with printing in dot-matrix mode.

Abstract: A method for printing an authentication pattern wherein, using a multi-deflection continuous inkjet printer, the pattern is printed on a substrate and only contains a small number of black pixels per raster. The resolution in the travel direction X of the substrate and in direction Y of the rasters is thereby largely improved compared with printing in dot-matrix mode, which makes reproduction of the pattern difficult for an infringer not having means to determine the electric charge to be applied to each of the droplets of a train of droplets needed to print each raster of the pattern.

Abstract: A method for printing an authentication pattern wherein, using a multi-deflection continuous inkjet printer, the pattern is printed on a substrate and only contains a small number of black pixels per raster. The resolution in the travel direction X of the substrate and in direction Y of the rasters is thereby largely improved compared with printing in dot-matrix mode, which makes reproduction of the pattern difficult for an infringer not having means to determine the electric charge to be applied to each of the droplets of a train of droplets needed to print each raster of the pattern.