FR2543450A1 - INK PRODUCTION APPARATUS - Google Patents

Abstract

THE INVENTION RELATES TO AN INK PRODUCTION APPARATUS. IT INCLUDES A SECTION 1 FOR THE PRODUCTION OF A COLORING MATTER SOLUTION WITH A LIMITED INORGANIC SALT CONCENTRATION, AND A SECTION 1 FOR THE PREPARATION OF INK FROM THE COLORING MATTER SOLUTION FROM THE PRODUCTION SECTION 2. FIELD OF APPLICATION: PREPARATION OF INK FOR RECORDING BY INKJET, ETC.

Description

An ink producing apparatus, and more

  especially a production apparatus

  of ink suitable for the preparation of a recording liquid

  (generally referred to as ink) suitable for ink jet recording or the like. So far, it is known as an ink for use in an ink jet recording apparatus which performs a recording of information by ink ejection using a recording head, through

  an ejection orifice, under the action of trans-

  put by a piezoelectric vibrator or by other means, various dyestuffs and various pigments which are dissolved or dispersed in a liquid medium such

  water or other organic solvents.

  It is known to use an ink similar to that described above in writing instruments such as felt pens, pen pens, etc. An example of general main ingredients for such an ink may include mainly

  three main constituents: a colored material

  water soluble solvent, water as a solvent for the substance

  dye, and glycols as an anti-desiccant agent.

  The water-soluble dyestuff usually contains

  a large amount of inorganic salts such as sodium chloride, sodium sulfate, etc.

  These inorganic salts are the by-products of the reaction

  dye synthesis, or are added voluntarily

  as a salting agent, diluent or leveling agent. When the recording ink is prepared

  using a coloring matter containing the inorganic salts

  ganic, embarrassing situations may appear

  inorganic salts lower the stability of the dissolu-

  of the coloring matter in the ink at a

  In addition, in the ink jet recording heads and the writing instruments, in the case where the ink evaporates near the ejection port. , i 4? Since this causes a change in the composition of the liquid, inorganic salts are deposited. These phenomena cause a clogging of the discharge orifice, which

  should be avoided with the utmost care.

  Therefore, to eliminate these defects,

  It is necessary to limit the concentration of inor-

  within a predetermined range when producing the ink (in general, it should be limited to 0.5% by weight or less in relation to the total composition of the ink) This limitation is essential when the coloring matter available in the general market, which contains inorganic salts as impurities, is

  used for the preparation of the ink for recording

  by ink jets as well as for the instruments

writing.

  In view of the points indicated above, the subject of the invention is an ink-producing apparatus

  in which, in the preparation of the ink, the concentration

  The inorganic salts contained in the ink can be adjusted, and this apparatus is suitable for producing ink suitable for ink jet recording, writing instruments, etc. The invention also relates to an ink-producing apparatus in which, in the preparation of the ink, the concentration of inorganic salts contained in the ink can be limited and the properties of the ink prepared can be determined, this apparatus suitable for producing ink suitable for ink jet recording, writing instruments, etc. According to one aspect of the invention, there is provided an ink producing apparatus characterized by the presence of a dye solution producing section in which the concentration of inorganic salts is limited, and a preparation section

  from the solution of coloring material

coming from the production section.

  According to another aspect of the invention, there is provided an ink producing apparatus characterized by the presence of a material feed section.

  dye comprising means for producing a moon

  of coloring material, means for limiting the concentration of coloring matter in the solution, and means for limiting the concentration of inorganic salts in the dyestuff solution, and

  that a section of ink preparation from the solu-

  of coloring material from the food section

  dye solution solution.

  According to another aspect of the invention, there is provided an ink production apparatus characterized by the presence of a dye solution producing section in which the concentration of

  inorganic salts is limited, of a preparation section

  ink from the dyestuff solution from the production section, and colorant concentration detecting means,

  means being located in the preparation section.

  According to another aspect of the invention, there is provided an ink production apparatus characterized by the presence of a dye solution producing section in which the concentration of

  inorganic salts is limited, of a preparation section

  ink solution from the dyestuff solution from the production section, and means for detecting the concentration of inorganic salts, these

  detection means being located in the pre-section

  repair. The invention will be described in more detail with reference to the accompanying drawings by way of non-limiting example and in which Figure 1 is a schematic view of an embodiment of the apparatus according to the invention; FIG. 2 is a schematic view of the section

  purification of coloring matter forming part of the

  FIG. 1 shows Figs. 3A and 3B are simplified diagrams of the control unit of the apparatus shown in Fig. 1; and FIGS. 4A and 4B are flowcharts showing the operation of the purification section of FIG.

  coloring material shown in Figure 2.

  FIG. 1 represents an embodiment

  of the ink production apparatus according to the invention -

  In FIG. 1, reference numeral 1 denotes an ink preparation tank fed with an aqueous solution of dyestuff purified from a section 2 of epuratin of dyestuff, via a valve 3, such as described below A water-soluble organic solvent and an additive come respectively from reservoirs 4

  and 5 and arrive at the preparation tank 1 through the intermediary

  In addition, pure water is supplied to the preparation tank 1 via a valve 8. These feedstocks are agitated by means of a stirrer 9 in such a way that to prepare

an ink.

  The quantity of ink produced in the preparation tank 1 is detected by a liquid quantity sensor 11. In addition, the concentration of coloring matter

  and the concentration of inorganic salts of the pre-ink

  in the tank 1 are detected by a colorant concentration sensor 11 and by a sensor 12

  concentration of inorganic salts, respectively.

  The final quality control (repetition control) of the prepared ink is performed on the basis of the output signals of these two sensors. The ink whose constituents have been prepared at desired values is discharged via a discharge valve 13, according to this

which is necessary.

  FIG. 2 shows the realization of the purification section of the coloring matter forming part of

the apparatus of Figure 1.

  In FIG. 2, the numerical reference 21

  The powdery coloring material 22 is directed from this supply section 21 into a preparation tank 24 via a valve 23. feeding material

  In addition, the preparation tank 24 also receives

  pure water through a tank 26 of food.

  in pure water carrying a valve 25 in a certain

point of its length.

  In this preparation tank 24, an aqueous solution of coloring matter is prepared by mixing and dissolving the powdery coloring material 22 and pure water by means of an agitator 27 installed in the preparation tank 24. The amount of solution aqueous liquid

  of coloring material staying in the tank 24 of preparation

  tion is detected by a liquid quantity sensor 28

  placed in this tank The aqueous solution of colored matter

  obtained in the preparation vat contains, in the form of a residue, particles of powdered dyestuff which have not been dissolved in pure water. This residual powder is removed by a filter 29.

  In the case of filter 29, ordinary filter paper can be used.

  or "FLUOROPORE" (trade mark of a product

  Sumitomo Denko K K, Japan, consisting of poly-

  tetrafluoroethylene as the main element), etc.

  aqueous solution of coloring matter, from which the

  residual molecules, etc. were removed by the filter

  29, is advanced towards a tank 31 of supply.

  The aqueous solution of coloring matter introduces

  The liquid supply control valve 33 is placed in the feed tank 31 in order to maintain the quantity of aqueous solution of the liquid. coloring matter to a certain

  level defined or below this level.

  Reference numeral 41 designates a section

  refining process in which the inorganic salts are

  In this refining section 41, the reference numeral 42

  designates a salt extraction tank, the numerical reference

  FIG. 43 denotes a salt extraction filter and numeral 44 designates a storage tank for the removed salts. The aqueous solution of coloring matter is introduced into the extraction tank 42 via the feed valve 32. solution of coloring material thus introduced is stirred by an agitator placed in the tank 42 of extraction of salts to be

  after which the concentration of inorganic salts

  the solution is detected by a sensor 46 sensitive to this concentration. This detection of the concentration of the inorganic salts is carried out, for example, by the

  In addition, the concentration of ion chromatography

  of the dyestuff in the aqueous solution

  is detected by means of a sensor 47 responsive to

  This detection of the concentration of dyestuff is effected, for example, by spectrophotometry As described hereinafter, when the concentration of inorganic salts is found to be greater than a predetermined value (for example 5% by weight per

  to the dyestuff), a circulating pump 48

  It is turned on to pass the aqueous solution of coloring matter contained in the salt extraction tank 42 through the salt extraction filter 43. As a salt extraction filter, it is possible to use, for example, a ultrafiltration device, a reverse osmosis filtration device, etc. By passing the dye solution through the salt extraction filter 43, the

  inorganic salts such as sodium chloride, sulphate

  sodium fate, etc., contained in the solution, the salts being removed in the form of an aqueous solution of these salts and discharged into the salt storage tank 44. As a result of this elimination of the salts, a part of the water, used as a solvent for the coloring matter, is also discharged into this salt storage tank 44, along with the inorganic salts. Therefore, to compensate for the part of the discharged water and to maintain the

  desired concentration for the solution of colored matter

  in the tank 42 of extraction of salts, pure water

  is introduced into this tank 42 by means of a valve 49.

  As described above, it is possible to obtain,

  in the tank 42 for extracting salts, a colored solution

  In the same time, the quantity of aqueous solution of coloring matter contained in the tank 42

  extraction of salts is detected by a sensor 50 sen-

  sible to the amount of liquid that the tank contains.

  Then, the aqueous solution of coloring matter, which has been purified (from which the salts have been extracted) in the manner described above is discharged into a reservoir

  52 storage of the refined dyestuff, by the in-

  intermediate of a storage valve 51, and is stored therein.

  The aqueous solution of coloring matter contained in the storage tank 52, as shown in FIG.

  is supplied to the preparation tank 1 by the command dlou-

  opening and closing of valve 3 and it is used

for the preparation of the ink.

  Figures 3A and 3B show the device

  of the apparatus shown in FIG.

  In FIGS. 3A and 3B, the reference numeral 61 designates a controller which controls the control and control of the various sections. The reference numeral 62 denotes a dead memory in which the control program is recorded, such as the operating process shown on the FIG. FIGS. 4A and 4B. The reference numeral 63 denotes a random access memory in which are recorded

temporarily various data.

  In the embodiment described, signals

  are emitted by sensors 12 and 46 of con-

  centration of inorganic salts and by sensors 11,

  47 concentration of coloring matter and they are trans-

  formed into digital signals by analog-to-digital converters 64, 65 and 66, 67, respectively,

  after which they are transmitted to controller 61 through

  Furthermore, digital signals are emitted by the sensor 10 responsive to the quantity of liquid in the ink preparation tank, by the sensor 28 responsive to the amount of liquid in the tank. of preparation and by the sensor 50 sensitive to the amount of liquid in the salt extraction tank, and they are transmitted to the controller 61 via

of the input buffer circuit 68.

  Numerals 71-84 designate the circuits intended to control the aforementioned valves 3, 6, 7, 8, 13, 23, 25, 49, 32 and 51, the stirrers 9, 27 and

  45 and the circulation pump 48, respectively These cir-

  Cookies 71-84 are controlled in all or nothing by control signals from the controller 61

  via an output buffer 85.

  Numerals 86 and 87 denote, respectively, range adjustment switches

  concentrations of dyestuff and inorganic salts

  The signals corresponding to these concentration ranges

  established by these switches are trans-

  put to controller 61 through a circuit

  console input-output buffer 88 The numerical references

  Figures 89 and 90 denote colorant concentration display devices and numerals 91 and 92 denote devices for displaying the concentration of inorganic salts. The value of

  concentration of dyestuff and the concentration value

  inorganic salts in the aqueous solution of coloring matter being purified are affixed by devices 89 and 91, respectively.

  the operator of the ink-producing apparatus can easily

  know the quality of the ink being produced.

  In addition, the concentration value of colored matter

  and the concentration value of the inorganic salts in the ink constituting the final product obtained in the

  tank 1 of ink preparation are displayed by the dis-

  90 and 92, respectively.

  may carry out the quality control

reception) of the ink produced.

  The values of the concentration ranges of

  coloring matter and concentrations of inorganic salts

  established by switches 86 and 87, respectively,

  are temporarily stored in the RAM 63.

  The detected concentration values of the inorganic salts and dyestuff in the aqueous solution of dyestuff during the purification operation, these values being detected by the inorganic salt concentration sensor 46 and the dye concentration sensor 47, respectively, are compared to the values established in a controller's comparison section 61 and, according to the result of the comparison, the

  various loads such as the pump 48 of

  The control is controlled as described below.

  93 denotes a printer designed to be turned on or off by a circuit

  controlled by the controller 61 through the

  94 of an output buffer circuit, this printer being intended to print the concentration values detected by the dye concentration sensor 11, 47 and the concentration sensors 12, 46

  inorganic salts, at predetermined time intervals.

  FIGS. 4A and 4B show the operating process of the material cleaning apparatus 2

  dye shown in Figure 2.

  In FIG. 4A, the steps ST 1 to ST 4 are intended to maintain the aqueous solution of matter

  colorant in a constant amount in the tank 24 of prepa-

  In a more detailed fashion, at ST 1, it is

  is detected, thanks to the output signal of the sensor 28 sen-

  the amount of liquid in the preparation tank, if the level of the aqueous liquid dye solution in the preparation tank 24 is above a lower position defining a predetermined predetermined range of the level of the liquid, If the liquid level

  is below the lower position, the continuation of

  rations goes to step ST 2; otherwise, it goes to step ST 3 O In step ST 2, the supply valve 23 in

254345 O

  The coloring material and the pure water supply valve 25 are open to fill the preparation tank 24 with predetermined amounts of powdered coloring material and pure water. In the preparation tank 24, since the agitator 27 operates from stably, the powdered dyestuff as charged is dissolved in pure water to form the aqueous dye solution. In step ST 3, it is detected by an output signal of the sensor 28 which is sensitive to amount of liquid, if the level of the liquid surface in the tank 24 of

  preparation is above a defined upper position

  predetermined range, or not. If it is not

  above the upper position, the sequence of operations goes to step ST 4 and, if it does not, it goes to step ST 5. In step ST 4, the supply valve 23 dyestuff and the water supply valve

  pure, then in their open state, are closed in order to stop

  ter the supply of powdered dyestuff and

pure water.

  In step ST 5, the dye concentration value in the solution contained in the salt extraction tank 42, this value being detected by the dye concentration sensor 47, is displayed on the device 90 same way, in step ST 6, the concentration value of the inorganic salts,

  detected by the sensor 46 of concentration of inorganic salts

  are displayed on device 92.

  At step ST 7, it is determined whether the concentration

  The coloring material as detected by the detector 47 is within the concentration range.

  of coloring matter established by the switch 86, or not.

  If it is within the established range, the following

  rations goes to step ST 8 and, if not, to

  step ST 9 In step ST 8, it is determined whether the

  The concentration of inorganic salts, as detected by the sensor 46, is or is not within the range of values established by the switch 87. If it is within the established range, the sequence of operations proceeds to a step

  ST 10 and, if not, at step ST 9.

  In step ST 9, it is determined whether the level of

  the surface of the liquid contained in the tank 42 of extrac-

  of the salts and as detected by the sensor 50 is

  above the upper position defining the range

  established, or not If it is below the sup-

  the sequence of operations moves to step ST 11, and,

  otherwise, at step ST 12 In step ST 11, the valve 32 for supplying food

  The water supply valve 49 and the water supply valve 49 are

  set open and close commands so as to supply the tank 42 for extracting the salts in aqueous solution of dyestuff and pure water to thereby control the dye concentration of the aqueous solution of dyestuff contained in the tank 42 for extracting the salts so that this concentration is within the range established by the switch 86,

  as mentioned above Then, the operational cycle

  In addition, operations to close the supply valve 32 and the valve

  49 water supply are performed at step ST 12.

  In step ST 13, the circulating pump 48 is turned on to circulate the aqueous dye solution of the salt extraction tank 42 through the salt extraction filter 43 so that the inorganic salts are removed from the aqueous solution

of coloring matter.

  As mentioned above, when the concentration

  If the amount of dyestuff and the concentration of inorganic salts are outside the established ranges, then the subprogram operations passing through steps ST 11 and ST 13 or steps ST 12 and ST 13 are repeated.

  to bring the concentration of coloring matter and the con-

  concentration of inorganic salts in their established ranges.

  After these two concentration values have been brought within established ranges, the sequence of operations

step ST 10.

  In step ST 10 Oil is determined whether the level of the liquid surface in the salt extraction tank 42, as detected by the sensor 50, is above

  the lower position defining the established range, or not.

  If it is above the lower position, the following

  operation proceeds to step ST 14 and, in the case

  In step ST 14, the circulation pump 48 is stopped and the storage valve 51 is opened. Consequently, a predetermined quantity of the aqueous solution of purified dyestuff, obtained in the tank 42, is removed. extraction of salts, is introduced in

storage tank 52.

  In step ST 15, the storage valve 51 is closed and the supply valve 32 and the valve 49 for supplying pure water are opened, thus completing the supply

  storage tank 52 purified solution and increased

  the amount of aqueous solution of coloring matter contained in the tank 42 for extracting the salts in order to bring

  the level of the liquid surface in the established range.

  Then, the operations of subprograms

  by steps ST 11 and ST 13 or steps ST 12 and ST 13, as mentioned above, are repeated again so that a quantity of aqueous solution is obtained in the tank 42 for extracting salts. of

  coloring matter whose concentration in colour-

  and the concentration of inorganic salts are

  taken within established ranges The following operations-

then proceeds to step ST 14.

  As previously described, in this embodiment, the aqueous dyestuff solution is purified for each particular defined amount contained in the purification section 41 and, therefore, the purified aqueous solution of dyestuff can be continuously dispensed from the purification section 2 of the dyestuff to the preparation tank I and the ink can be produced continuously in the preparation tank 1

  from the purified aqueous solution of dyestuff.

  In the embodiment described above,

  the design is such that the detected value of the con-

  Colorant centering is printed and issued at predetermined time intervals, although the invention is not limited thereto. For example, the detected value can be stored in the random access memory so that it can be printed and transmitted to a desired period, by operating a control key of

  pressure forming part of the maneuver section.

  Moreover, in the embodiment described above, the design is such that the detected value of the concentration of inorganic salts is printed and emitted at predetermined time intervals, whereas the invention is not limited to those For example, the detected value may be stored in the RAM so that it can be printed and transmitted at a desired time by operating a control key.

  printing being part of the maneuvering section.

  Further, in the embodiment described above, the design is such that the detected value of the dye concentration is constantly displayed and printed and issued at predetermined time intervals, while the invention is not limited. To these, for example, a switching key can be arranged in the operating section so that one or other of the display functions of the detected value and the print-emission of the detection value can

be performed as necessary. In addition, in the embodiment described above, the design is

  such that the detected value of the concentration of inorganic salts is constantly displayed and printed and transmitted at predetermined time intervals, whereas the invention is not limited thereto. For example, a switching key may be arranged in the operating section so that one or other of the functions of display of the detected value and print-emission of the detected value

  can be performed as needed.

  As described above, the apparatus according to the invention produces the following effects:

  an ink having stable quality, when

  that it is used for recording by ink jets or other, can be produced continuously and automatically; the final product can be obtained on the basis of the result of the detection, and an ink having a stable cavity can be prepared when used for ink jet recording or the like; the quality of the ink constituting the final product can be controlled from the display, and an ink of stable quality can be prepared when used for ink jet recording or the like; the quality of the ink constituting the final product can be controlled by the recording and an ink having a stable quality can be prepared when used for ink jet recording or the like; and the permanent control of the quality of the ink constituting the final product can be effected by means of the displayed value and the state of the ink, varying in time, can be confirmed by the value recorded, and an ink with stable quality can also be produced when used for jet recording

ink or other.

  It goes without saying that many modifications can be made to the apparatus described and shown

  without departing from the scope of the invention.

Claims (6)

  Ink producing apparatus, characterized in that it comprises a section (2) for producing a solution of coloring material whose concentration of inorganic salts is limited, and a section (1) of preparation   from the solution of coloring material   from said production section.   2 Apparatus according to claim 1, characterized in that the dyestuff solution producing section comprises means (2) for purifying the dyestuff by removing the inorganic salts from the dyeing material. solution of coloring matter.   Apparatus according to claim 1, characterized in that the dye solution production section comprises means (12) for detecting the concentration of inorganic salts.   4 Apparatus for producing ink, characterized in that it comprises a section (2) for supplying   dyestuff solution comprising means for   produced to produce a solution of coloring matter, means for limiting the concentration of coloring matter in the dyestuff solution produced and means (42, 43) for limiting the concentration   inorganic salts in the solution of colored matter   and a section (1) for preparing ink from the dye solution from the section   feeding solution of dyestuff.   Ink production apparatus, characterized in that it comprises a section (2) for producing a solution of coloring matter whose concentration in   inorganic salts is limited, a section (1) of prepara-   ink injection from the dyestuff solution from the production section, and dye concentration detection means (11),   these means being arranged in the preparation section.   Apparatus according to claim 5, characterized   in that it further comprises means (89 92) for displaying the output signal of the means for 254345 O detection.   Apparatus according to claim 5, characterized   characterized in that it further comprises means (93) for recording the output signal of the detection methods. 8 Apparatus for producing ink, characterized in that it comprises a section (2) for producing a solution of coloring material whose concentration in   inorganic salts is limited, a section (1) of prepara-   ink from the dye solution from the ink producing section; and means (12) for detecting the concentration of inorganic salts, which means are located in the preparation section. Apparatus according to claim 8, characterized in that it further comprises means (89-92) for   to display the output signal of the detection means.   Apparatus according to claim 8, characterized   in that it also includes means (93) for   to record the output signal of the detection means. i -