JPS6072739A - Ink making apparatus - Google Patents

Abstract

PURPOSE:To form an ink making apparatus ideal for making ink suited to inkjet recording, writing tools and the like by removing inorganic salts and heavy metal ion contained in a dye solution by membrane separation and ion exchange separation method. CONSTITUTION:A refining section 100 of a dye aqueous solution has a refining section 100A for removing inorganic salts by membrane separation and a refining section 100B for removing heavy metal ion by ion exchange separation. In other words, membrane separation is executed to remove inorganic salts contained in a dye solution while ion exchange separation is done to remove heavy metal ion therein and then, the refined dye solution is used to prepare an ink. This enables the formation of an ink with the quality ideal for use in inkjet recording and writing tools.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an ink manufacturing apparatus that continuously manufactures a recording liquid (generally referred to as ink) particularly suitable for inkjet recording, writing instruments, and the like.

[Prior Art] Conventionally, ink used in the inkjet recording method, in which recording is performed by ejecting ink in a recording head from an ejection orifice using vibrations caused by a piezo vibrator, has been made by mixing various dyes and pigments with water or other organic solvents. It is known to be dissolved or dispersed in a liquid medium consisting of: It is also known that similar inks are used in writing instruments such as felt pens and fountain pens.

An example of a general basic composition of such an ink is one in which the main components are a water-soluble dye, water as its solvent, and the king of glycols as an anti-drying agent.

Here, the water-soluble dye usually contains a large amount of inorganic salts such as sodium chloride and sodium sulfate, and heavy metal ions.

When recording inks are prepared using dyes containing such inorganic salts and heavy metal ions, the following disadvantages occur. That is, inorganic salts and heavy metal ions reduce the dye dissolution stability in the ink, leading to aggregation and precipitation of the dye. In addition, in inkjet recording heads and writing instruments, when the ink evaporates near the ejection orifice (=I) and the liquid composition changes, it causes the precipitation of inorganic salts and heavy metals. This may cause clogging.

Therefore, in order to eliminate such adverse effects, it is necessary to control the concentrations of inorganic salts and heavy metal ions to fall within predetermined ranges during ink production. This is essential when common commercially available dyes containing inorganic salts and heavy metal ions as impurities are used in the preparation of inkjet recording inks and writing instrument inks.

[Objective] In view of these points, the object of the present invention is to remove inorganic salts and heavy metal ions contained in a dye solution by a membrane separation method, an ion exchange method, etc. when preparing an ink. Therefore, it is an object of the present invention to provide an ink manufacturing apparatus suitable for manufacturing ink suitable for inkjet recording, writing instruments, and the like.

[Example] The present invention will be described in detail below with reference to the drawings.

FIG. 1 shows the overall configuration of an embodiment of the apparatus of the present invention.

Here, l is a production department that manufactures an aqueous dye solution, and 100 is a purification section for the aqueous dye solution, in which a purification section 100A removes inorganic salts by a membrane separation method and heavy metal ions are removed by an ion exchange separation method. It has a purification section 100B. An ink preparation section 200 prepares ink using the purified dye aqueous solution supplied from the purification section 100.

Reference numeral 300 denotes a control section, which controls the driving of each section mentioned above.

FIG. 2 shows the structure of the dye solution manufacturing section 1 shown in FIG.

Here, 3 is a dye supply section that stores dye powder 5,
The dye powder 5 is supplied to a mixing tank 8 via a dye valve 7. Further, pure water is supplied to the mixing tank 9 through a pure water supply pipe 13 in which a pure water/help 11 is inserted.

In this mixing tank 8, the supplied dye powder 5 and pure water are mixed and dissolved by a mixing tank agitator 15 to prepare an aqueous dye solution. The amount of the aqueous dye solution stored in the mixing tank 8 is detected by a mixing tank liquid amount detector 17. The aqueous dye solution obtained in the mixing tank contains particles of dye powder that were not dissolved in the pure water, and these are removed by the filter 18. For this filter 18, ordinary filter paper, Fluoropore (trade name), or the like can be used. The aqueous dye solution from which particles and the like have been removed by passing through the filter 18 is supplied to the supply tank 21 .

The aqueous dye solution supplied to the supply tank 21 is supplied to the purification section 100, which will be described next, via the supply pipe 23. Here, this supply tank 21 is provided with a valve 25 for controlling the liquid level,
To suppress the amount of dye aqueous solution stored in the supply tank to a certain amount or less.

FIG. 3 shows a purification section 10θA for removing inorganic salts from the dye aqueous solution in the purification section +00 of FIG. In the figure, 101 is a salt reduction tank, 103 is a salt reduction filter, and 10
5 is a salt removal tank. The salt reduction tank 101 has a supply valve 107.
The aqueous dye solution is supplied through the . The supplied aqueous dye solution is stirred by a salt reduction tank stirrer 1013 to homogenize the aqueous solution, and the inorganic salt concentration in the aqueous solution is detected by an inorganic salt concentration detector 111. This concentration detection is
For example, ion chromatography is used. Also,
A dye concentration detector 113 detects the dye concentration in the aqueous solution. This concentration detection is performed, for example, by spectrophotometry. As described later, when it is detected that the inorganic salt concentration is higher than a predetermined value (for example, 5% by weight based on the dye), the circulation pump 115 is operated to reduce the salt content of the dye aqueous solution in the salt reduction tank. It is circulated through filter 103. As this salt reduction filter, for example, an ultrafiltration filter or a reverse osmosis filter is used. Such a salt-reducing filter 103
By passing through the dye aqueous solution, inorganic salts such as sodium chloride and sulfur and sulfate contained in the dye aqueous solution are filtered from the dye aqueous solution as an aqueous solution and discharged to the salt drainage tank 105. In this way, the salt removal tank 105 contains dye #i°.
A portion of the medium, water, is discharged together with the inorganic salts.

Therefore, in order to replenish the dye aqueous solution with this discharged water and to obtain a dye aqueous solution with a desired concentration in the 1 g salt tank 101, the salt-reducing tank 101 is connected to the deionized water valve +17.
Supply pure water to 01.

In this way, an aqueous dye solution having an inorganic salt concentration and a dye concentration within a predetermined range is obtained in the salt reduction tank 101.

Note that the amount of dye aqueous solution in the salt reduction tank 101 is detected by a salt reduction tank liquid amount detector 119. As mentioned above (low salt)
The purified aqueous dye solution is supplied via the storage valve 121 to the supply tank 181 of the purification unit XGOB, which is to be operated next.

FIG. 4 shows the configuration of a purification section 100B that removes heavy metal ions from the dye aqueous solution in the purification section 100 of FIG.

Here, the aqueous dye solution from which inorganic salts have been removed in the purification section 100A is supplied to the supply tank +61. This supply tank 1
A supply tank liquid level detector 163 is disposed at 61, and the valve 121 is opened and closed based on the output of the sensor 163 to control the liquid level in the supply tank 181.

The purification unit 100B includes a plurality of processing units, in this example, three first to third processing units IFi5-1 and 165-2.
and 165-3. Each processing unit +65 (1
85-1 to 185-3), the aqueous dye solution in the supply tank 161 is supplied to the supply valve 1137 (187-1 to 1B?-).
3) through the ion exchange resin column IH (1f19-1
~1611-3). Ion exchange resin column 1
fi13 separates heavy metal ions from the dye aqueous solution by so-called ion exchange separation. That is, due to ion exchange within the column, highly adsorbable heavy metal IN ions contained in the aqueous dye solution are captured by the ion exchange resin and remain within the column. Here, valves 17+ (1711 to 171-3) for controlling the liquid level are provided in the column to control the amount of the aqueous dye solution supplied into the column. Further, the column 168 is made detachable from the processing unit, and whether or not a column is attached is detected by a filter replacement end switch (not shown).

Next, heavy metal ion concentration detector +73 (+73-1 to 17
3-3) is placed in the outflow solution passageway at the lower end of column 169 to detect the heavy metal ion concentration in the outflow solution from column 168. As a method for detecting the heavy metal ion concentration, for example, a measurement method using a metal ion electrode or a measurement method using atomic absorption spectroscopy is used. Solution detector 1
75 (+75-1 to +75-3) are similarly disposed in the outflow solution passage, and detect the presence or absence of the outflow solution in the outflow solution passage.

The effluent solution from the column 168 is transferred to the first discharge valve 17?
(17?-1-177-3) to the storage tank 178. In addition, the second discharge valve +81 (181-1 to 1
81-3), by the action of the circulation pump 183,
It is refluxed to the supply tank 181. Both valves 177 and 18
Heavy metal ion concentration detector 1
This is done based on the detection results of 73.

The aqueous dye solution obtained in the storage tank 178 from which heavy metal ions have been removed is supplied to the ink preparation unit 2 via the supply valve 185.
Supply to 00.

FIG. 5 shows the configuration of the ink preparation section 200 shown in FIG. 1. Here, 2+11 is an ink preparation tank, and a dye aqueous solution purified as described above is supplied from the purification section 100 to a valve 18.
5. Further, the water-soluble organic solvent and additives are supplied from the storage section 203 and the storage section 205 to the mixing tank 201 via valves 207 and 209, respectively. Furthermore, pure water is also supplied via the valve 211. Each of these supplied materials is stirred by a stirrer 213 to prepare ink.

The amount of ink produced in the mixing tank 100 is detected by a liquid amount detector 215. Further, the dye concentration, inorganic salt concentration, and heavy metal ion concentration in the ink prepared in the mixing tank 201 are measured by a dye concentration detector 217. Detection is performed by an inorganic salt concentration detector 219 and a heavy metal ion concentration detector 221. Based on the output of these detectors,
Final property control (lot control) of the prepared ink is performed as described below. The ink whose components have been adjusted to desired values is taken out via the discharge valve 223 as necessary.

Reference numeral 225 is an operation unit including various display units and drive switches, and 227 is a printer that prints out various data. In the display section of the operation section 225, 225-1, 225
-2 and 225-3 are a dye concentration indicator, an inorganic salt concentration indicator and a heavy metal ion concentration indicator, respectively;
Dye concentration detector 2t', H machine salt concentration detector 2, respectively
18 and the detection results of the heavy metal ion concentration detector 221 are displayed. That is, the display shows the ink preparation tank 201.
The dye concentration value in the ink as the final product obtained within
Inorganic salt concentration values and heavy metal ion concentration values are displayed. Based on this display result, the operator can manage the properties (loft management) of the manufactured ink.

The printer 227 also has detectors 217, 219 and 2.
The detection results of 21 are printed out at regular intervals. Based on this output result, the operator can monitor changes in the properties of the manufactured ink over time.

FIG. 6 shows a portion related to the purification section 100A in the control section 300 of the apparatus shown in FIG.

In the figure, 301 is a controller that controls the drive of each part. Reference numeral 302 denotes a read-only memory (RO) 0, in which control programs such as the operating procedures shown in FIGS. 8 and 9 are stored. 303 is a random access memory (RAM) in which various data are temporarily stored.

In this example, analog signals are output from the inorganic salt concentration detection section 111 and the dye concentration detector 113, and after being converted to digital signals via A/D converters 304 and 305, respectively, the input buffer 7 circuit 30B is supplied to the controller 301 via. On the other hand, the salt reduction tank liquid level detector 118
A digital signal is output from the input/header circuit 3.
06 to the controller 301.

307 to 311 are the aforementioned valves 117, 107, 1
21, a drive circuit for driving the stirrer 108, and the circulation pump 115, respectively, and the controller 301
On/off control is performed by a drive signal supplied from the output buffer circuit 312 through the output buffer circuit 312.

321 and 322 are a dye concentration range setting switch and an inorganic salt concentration range setting switch, respectively, and signals corresponding to the set concentration ranges are sent to the crowd buffer circuit 3.
23 to the controller. 324 and 325
are a dye concentration indicator and an inorganic salt concentration indicator, respectively, and display the dye concentration value and the inorganic salt concentration value in the aqueous dye solution being purified. Therefore, the operator of the ink manufacturing apparatus can easily know the quality of the ink being manufactured.

The dye concentration range and inorganic salt concentration range settings set by switches 321 and 322 are temporarily stored in RAM 303. The detected concentration values of inorganic salts and dyes in the aqueous dye solution being purified, which are detected by the inorganic salt concentration detector 111 and the dye concentration detector 113, are compared with the set values in the comparison section 313 of the controller, and the comparison results are Based on this, the driving of each load such as the circulation pump 115 is controlled as described later.

FIG. 7 shows a portion related to the purification section 100B in the control section 300 of the apparatus shown in FIG.

In the figure, the detection output of the supply tank liquid level detector 163 is supplied to the controller 301 via an input buffer circuit 331. Drive circuits 332 and 333 operate on each load (pulp 185, pump 18
3) On/off control.

335 is various switches, and input/output buffer circuit 33
Various command signals are sent to the controller 301 via the controller 6. 3
37 is an indicator, and as described later, there is a first to third unit filter replacement indicator that indicates that the column in each processing unit of the purification section 100B needs to be replaced, and a display that indicates that each processing unit also has a dye aqueous solution. It has first to third unit operation indicators that indicate that the refining operation is in progress. A drive circuit 338 controls the display of the display 337 based on a drive signal from the controller 301.

Next, the detection signal from the heavy metal ion concentration detector 173-1 is digitized via the A/D converter 341 and then supplied to the controller 301 via the input buffer 7 circuit 342. Further, a digital detection signal is output from the solution detector 175-1 and is supplied to the controller 301 via the input packer circuit 342. 343°344 and 345
are each of the above-mentioned valves 187-1, 177-1 and 18
This is a drive circuit for opening and closing each of the circuits 1+ and 1+, and is controlled to be turned on or off by a drive signal supplied from the controller 301 via the output buffer circuit 348.

In addition, since the configuration of each processing unit 185-1 to 185-3 is the same, in the figure, other units 165-2
and 1135-3 shall be omitted.

FIG. 8 shows the operating procedure of the dye solution production section 1 and the purification section 100A of this embodiment configured as described above.

In the figure, steps ST1 to ST4 are steps for maintaining the dye aqueous solution in the mixing tank 8 at a constant amount. That is, procedure ST
In I, it is detected from the output of the mixing tank liquid φ detector 17 whether the liquid level of the dye aqueous solution in the mixing tank 8 is above a low position that defines a predetermined setting range. . If it is below the low position, proceed to step ST2; otherwise, proceed to step ST3. In step ST2, the dye valve 7 and the pure water valve 11 are opened, and predetermined amounts of dye powder and pure water are respectively put into the mixing tank 17. In the mixing tank 9, since the stirrer [15] is always in operation, the dye powder introduced is dissolved in pure water and an aqueous dye solution is prepared. In step ST3, it is detected based on the output of the liquid amount detector 17 whether or not the liquid level in the mixing tank 8 is above a high position that defines the setting range. If it is above that high position, proceed to step ST4, otherwise proceed to step ST5.
Proceed to. In step ST4, the dye valve 78 in the open state
and close the pure water valve 13 to stop the supply of dye powder and pure water.

In step ST5, the dye concentration value in the dye aqueous solution in the salt reduction tank 101 detected by the dye concentration detector 113 is
It is displayed on the display 324. In step ST6, the inorganic salt concentration value similarly detected by the inorganic salt concentration detector 111 is displayed on the display 325.

In step ST7, it is determined whether the dye concentration detected by the detector 113 is within the dye concentration range set by the switch 321. If it is determined that it is within the set range, the process proceeds to step ST8; otherwise, the process proceeds to step ST9. In step ST8, it is determined whether the concentration of inorganic salts detected by the detector 111 is within the range of values set by the switch 322. If it is determined that it is within the set range, the process proceeds to step 5TIO, and if not, the process proceeds to step ST9.

In step 5TII, it is determined whether the liquid level in the salt reduction tank 101 detected by the detector 119 is above the high position that defines the setting range. If it is below that high position, proceed to step 5TII, otherwise proceed to step 5T12. In step 5TII, the supply valve 107 and the pure water valve 117 are controlled to open and close to supply the aqueous dye solution and pure water into the salt reduction tank 101. As a result, the dye concentration in the dye aqueous solution in the salt reduction tank 101 can be adjusted as described above.
adjustment so that it falls within the range set by the inch 321. After this, the process proceeds to step 5T13. On the other hand, step 5T12
Now, the supply valve 32 and the pure water valve 117 are closed.

In step 5T13, the circulation pump 115 is operated to circulate the dye aqueous solution in the salt reduction tank 101 through the salt reduction filter 103 to remove inorganic salts from the dye aqueous solution.

As mentioned above, if the dye concentration and inorganic salt concentration are outside the set range, repeat the routine through step 5TII and step 5T13 or step 5T12 and step 5iT13 to bring the dye concentration and inorganic salt concentration to values within the set range. Nasu. After the image density is within the set range, proceed to step 5.
Proceed to TIO.

In step 5TIO, it is determined whether the liquid level in the salt reduction tank 101 detected by the detector 118 is above the low position that defines the setting range. If it is above the low position, proceed to step 5T14, otherwise proceed to step 5T15. In step 5T14, the operation of the circulation pump 115 is stopped and the valve 121 is opened.

As a result, a predetermined amount of purified dye aqueous solution obtained in the salt reduction tank 101 is supplied to the supply tank 1fil of the purification section 100B.

In step 5T15, the valve 121 is closed and the supply valve 107. The pure water valve 117 is opened to end the supply to the purification section 100B, and the amount of dye aqueous solution in the salt reduction tank 101 is increased so that the liquid level is within the set range. .

After this, repeat the routine that goes through steps 5TII and 5T13 or steps 5T12 and 5T13 described above,
A predetermined amount of an aqueous dye solution whose dye concentration and inorganic salt concentration are within a set range is obtained in the salt reduction tank 101 .

After this, the process proceeds to step 5T14 described above.

As mentioned above, in this embodiment, the purification section 100A
In this process, the aqueous dye solution is purified in constant quantities, and the aqueous dye solution from which inorganic salts have been removed to a predetermined concentration or less can be continuously supplied to the purification section 100B.

FIG. 8 shows the operation of each processing unit in the purification section 100B.

In the refining section 100B, based on the detection output of the heavy metal ion concentration detector 173, each processing unit) 165-1 to 165-18
5-3 are sequentially replaced to remove heavy metal ions from the dye aqueous solution supplied from the purification section 100A. That is,
The ion exchange resin in the ion exchange resin column 189 has a limited ability to capture heavy metal ions.
Once a certain amount of heavy metal ions have been adsorbed, ion exchange separation is no longer performed. As a result, the dye solution containing heavy metal ions is discharged as is, and the concentration of heavy metal ions in the solution flowing out from column LH increases. By detecting this concentration increase, the use of the ion exchange resin column is disabled, and subsequent purification of the dye solution is performed using either of the other two columns. In addition, an ion exchange resin column that is no longer usable is replaced with a new column, or the ion exchange resin is regenerated so that it can be purified again in the processing unit. FIG. 9 shows the operation of each processing unit, and each flag in the figure is used to make the following determination.

Unit filter replacement flag: This is a flag that instructs to replace the filter in each processing unit, that is, the ion exchange resin column. When this flag is turned on, the corresponding unit filter replacement indicator will display that filter 0 needs to be replaced. be done.

Unit change request flag: A flag that requests a change in the processing unit 7L. When this flag is turned on, the processing unit indicated by the unit reverse folding counter is selected, and the dye refining operation is transferred to that processing unit.

Unit operation flag: A flag indicating that the corresponding processing unit has been activated.

Unit in operation flag: A flag indicating that the corresponding processing unit is in operation.

Unit discharge flag: A flag that is turned on when the concentration of heavy metal ions in the solution flowing out from the column in the corresponding processing unit exceeds a set value, and instructs the pump 183 to start refluxing the solution to the supply tank 181.

Next, each procedure shown in FIG. 9 will be explained.

In FIG. 9(A), in step 5 TIOI, each display and data are initialized. In step 5T102, the processing unit change request flag is turned on, and the contents of the unit selection counter are set to "1". In step 5T103,
Based on the force detected by the supply tank liquid level detector 163, it is determined whether a predetermined amount of dye aqueous solution is stored in the supply tank 181.

When the predetermined amount is stored, the dye solution supply valve 133 is closed in step 5T104, and then step 5T10 is performed.
Proceed to step 8. However, if the predetermined amount has not been reached, the supply valve 133 is opened in step 5T105 to supply the aqueous dye solution to the supply tank.

Procedure 5T10B is a processing procedure when there is a filter replacement request to the first processing unit 165-1, and step 5T1
013-1-'5T10B-3. First, move 1 [
If it is determined in 5T10B-1 that the first unit filter replacement flag is in the on state, step 5T1013
-2, it is determined whether or not the first unit filter replacement end switch is on. If it is on, follow step 5.
lot(-3), the first unit filter replacement flag is turned off, and the display indicating that replacement is required, which was displayed on the first unit filter replacement display, is erased.

After this, the process advances to step 5T107. In addition, step 5T108
-1, when the filter replacement flag is off, and when the filter replacement end switch is off in step 5TIO13-2, follow the flow of "NO" to step 5T10.
Proceed to step 7.

Step 5T107 and step 5T108 are the second
processing unit) 165-2 and third processing unit 16
5-3 is a processing procedure when there is a filter replacement request, and its contents are the same as step 5TI08, so the explanation thereof will be omitted.

At step +11115T109, it is determined whether or not the unit change request flag is in the on state, and if the determination is affirmative, the process proceeds to step 5TIIO, and if the determination is negative, it is shown in FIG. 8 (B).
(7) Proceed to step 5T1113. In step 5TIIOTE, the content of the unit selection counter is determined, and if the content is "1", proceed to step 5T113, if it is "2", proceed to step 5T114, and if it is "3", proceed to step 5T115. .

Steps 5T113 to 5T115 are performed in each processing unit 185-
1 to 3 This is a processing procedure when 185-3 is selected. Since the contents of each of these steps 5T113 to 5T115 are the same, step 5 when the first processing unit) 185-1 is selected.
The contents of T113 will be explained. First, step 5T113-1
Then, it is determined whether the first unit filter replacement flag is in the off state. If the judgment is negative, step 5T113
-5, and if the determination is affirmative, the process advances to step 5T113-2. In step 5T113-2, the first unit operating indicator is turned on to indicate that the first processing unit 185-1 is operating. In step 5T113-3, supply valve 1
87-1 and second discharge valve 181-1 are opened.

Subsequently, in step 5T113-4, the first unit operation flag is turned on and the unit change request flag is turned off. Next, in step 5T113-5, the content of the unit selection counter is set to "2", and then the process proceeds to step 5T11B. Here, the content of the unit selection counter is r2
It is a ring counter that changes in the order of J, r3J, rlJ, r2J,..., and its content changes to "3" by executing step 5T114, and the content changes to "3" by executing step 5T114.
By executing II5, the content of Part 4 changes to "1".

Next, steps 5T118, 5T117 and 5T118 in FIG. 8(B) are steps for controlling the discharge of the effluent solution from the ion exchange resin column in each processing unit, respectively. Since the content of each of these procedures is the same, procedure 5T118 indicating control in the first processing unit) 1135-1
The contents will be explained only for the following.

First, in step 5T118-1, it is determined whether the first unit operation flag is in the on state. If the determination is negative, the process jumps to step 5T118-5, and if the determination is affirmative, the process advances to step 5T1113-2. In step 5T11B-2, it is determined whether the heavy metal ion concentration in the column outflow solution detected by the heavy metal ion concentration detector 173-1 is below a set value.

If the determination is negative, the process proceeds to step 5T11B-5, and if the determination is affirmative, the process proceeds to step 5T118-3. Step 5T1113-3
Now, close the second discharge valve 181-1 and release the first discharge pulp 17? Open -1. As a result, the dye aqueous solution from which heavy metal ions have been removed to a concentration value below the set value in the ion exchange resin column 168-1 is discharged to the first discharge valve +77.
-1 into the storage tank 178. Next, in step 5T1113-4, the first unit operation flag is turned off, and the first unit operation flag is turned on, and then step 5T1
Proceed to 1B-5.

Step 5T11E! At step -5, it is determined whether the first unit operating flag is in the on state.

If it is in the off state, the process proceeds to step 5T118-10, and if it is in the on state, the process proceeds to step 5TIIθ-8. Procedure ST11B-
In step 13, it is determined whether the concentration detected by the heavy metal ion concentration detector 173-1 exceeds a set value. If the set value is not exceeded, proceed to step 5T11B-10.
If it is exceeded, proceed to step 5T11B-7. Step 5T11f! After turning off the first unit operation indicator at step -7, proceed to step 5T11fl-8, and supply valve 1B? -1 and close the first discharge valve 177-1. Further, the second discharge valve 181-1 is opened, and the circulation pump 183 is driven to start a reflux operation in which the effluent solution from the column 189-1 is returned to the supply tank 181 via the second discharge valve 1811. . Next, step 5T109
, the first unit operating flag is turned off, and the first unit is turned off.
After turning on the unit discharge flag, proceed to step 5T11f (
-Go to 10.

Next, in step 5T11B-10, it is determined whether the first unit ejection flag is in the on state, and if it is in the off state, step 5T11? If it is in the on state, the process advances to step 5T118-11. In step S, T11fi-11, it is determined whether the solution detector 175-1 installed in the outflow solution passage of column +8fl-1 is off, that is, whether or not the outflow solution remains in the outflow solution passage. It will be judged.

If it is not in the OFF state, that is, when a solution is detected, proceed to step 5T117, and if it is in the OFF state, proceed to step 5T.
Proceed to 118-12. This off state means that all of the aqueous dye solution discharged from the column IH-1 and whose heavy metal ion concentration value is higher than the set value has been refluxed to the supply tank 161. In step 5T11B-12, the first unit filter replacement indicator is turned on to indicate that the column of the first processing unit needs to be replaced. Next, in step 5T116-13, the second discharge valve 181-1 is closed, the drive of the bomb 183 is stopped, and the recirculation operation is stopped.

Next, in step 5TII8-14, the first unit discharge flag is turned off, the first unit filter replacement flag is turned on, and the unit change request flag is turned on. After this, step 5TII? Proceed to.

Next, after going through steps 5T117 and 5T118, the process returns to step 5T103 shown in FIG. 8(A).

By executing each of the steps described above, the aqueous dye solution is purified in each of the processing units 185-1 to 15-3, and the purified aqueous dye solution whose heavy metal ion concentration is below the set value is transferred to the storage tank 1. ?9 can be obtained.

In this way, the purified dye aqueous solution from which inorganic salts and heavy metal ions have been removed is obtained in the storage tank 17e by the purification units 100A and 100B, and as described above, the ink preparation unit 200 prepares ink using this purified dye aqueous solution. will be done.

[Effects] As explained above, according to the present invention, the membrane separation method is performed to remove inorganic salts contained in the dye solution, and the ion exchange separation method is performed to remove heavy metal ions in the dye solution. Since the purified dye solution is used to prepare the ink, it is possible to produce an ink having a quality suitable for use in inkjet recording and writing instruments.

Furthermore, according to the present invention, such a purified dye solution can be produced continuously and automatically, making it possible to mass produce high quality ink.

In the above example, the dye solution was purified by removing inorganic salts by performing a membrane separation method and then removing heavy metal ions by performing an ion exchange separation method. Of course, the opposite may be true.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing an embodiment of the apparatus according to the present invention, FIG. 2 is a configuration diagram showing the dye solution production section of FIG. 1, and FIG. 3 is an inorganic salt purification section in the purification section of FIG. 1. 4 is a block diagram showing the heavy metal ion purification section in the purification section of FIG. 1, FIG. 5 is a block diagram showing the ink production section of FIG. 1, and FIGS. 6 and 7 are respectively A block diagram showing a part of the control section in FIG. 1. FIG. 8 is a flowchart showing the operation of the processing unit of the inorganic salt purification section in FIG. It is a flowchart showing the operation of the processing unit of the heavy metal ion purification section. Dye solution production department 1 3...Dye supply unit, 5...Dye powder, 7...Dye valve, 9...Blending tank, 11...Pure valve, 13...Pure water supply Pipe, 15... Preparation tank stirrer, 17... Preparation tank liquid level detector, 19... Filtration filter, 21... Supply tank, 23... Supply pipe. Purification Department 100 (100A, 100B) 100A・
...fIf, mechanical salt purification section 101...salt reduction tank. 103... Salt reduction filter, 105... Salt removal tank, +07... Supply valve, 109... Salt reduction tank stirrer, 111... Inorganic salt concentration detector, 113... Dye concentration detection 115... Circulation pump, 117... Pure water valve, 12+... Storage valve, 100B... Heavy metal ion purification section, 1131... Supply tank, 1 1B3... Supply tank liquid level detection 165... Processing unit, 187... Supply valve, 189... Ion exchange resin column, 171... Valve, 173... Heavy metal ion concentration detector, 175... Solution detector, 177 ...First discharge valve, 178...Storage tank, 181...Second discharge valve, 183...Circulation pump. In-line preparation section 200 201... Ink preparation tank, 203... Storage section, 205... Storage section, 207... Valve, 209... Valve, 211... Valve, 2 213. ... Stirrer, 215... Liquid amount detector, 217... Dye concentration detector, 218... Inorganic salt concentration detector, 221... Heavy metal ion concentration detector, 223... Discharge valve. j ′ standing 300 301...Controller, 302...Read-only memory, 303...Random access memory, 304.305
...A/D converter, 308...Input buffer circuit, 307-311...Drive circuit, 312...Output 4727 circuit, 313...Comparison section, 321...Dye concentration range setting switch , 322...
Inorganic salt concentration range setting switch, 323... Input/output buffer circuit, 324... Dye concentration display, 325... Inorganic salt concentration display, 331... Input buffer circuit, 332.333... Drive Circuit, 334... Output buffer circuit, 335... Switch, 336... Input/output buffer circuit, 337... Display device, 338... Drive circuit, 341... A/D converter, 342 ...Input buffer circuit・343.344,345...Drive circuit, 346・
...Output buffer circuit. Patent applicant Canon Co., Ltd. Fig. 7 331 163 Air entry /) Test 1 Each drop 301 337 338 336 1 + l Surprise - Unknown drink Dry 2

Claims (1)

[Scope of Claims] A means for producing a dye solution, and a first method for removing inorganic salts from the dye solution by membrane separation.
a second solution treatment means for performing ion exchange separation to capture heavy metal ions in the dye solution; and a dye solution purified by the first and second solution treatment means to ink. An ink manufacturing device comprising: an ink preparation section that performs preparation. (Margin below)