JP2012183645A - Method of inspecting liquid drop discharge head, method of manufacturing the same and test liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of inspecting a liquid drop discharge head requiring no complicated replacing work both in the case of using it as a head for discharging an aqueous ink containing a pigment as a colorant and in the case of using it as a head for discharging a treatment liquid containing a coagulant coagulating the pigment as a result of discharge characteristic inspection.SOLUTION: The method of inspecting the liquid drop discharge head discharging the aqueous ink containing the pigment as the colorant or the treatment liquid 13 containing the coagulant coagulating the pigment includes a test liquid introduction process of introducing a test liquid 12 into the liquid drop discharge head, and the inspection process of inspecting the discharge characteristic by discharging the test liquid from the liquid drop discharge head to a recording medium to determine whether the liquid drop discharge head is used as the aqueous ink discharging head or the treatment liquid discharging head. The test liquid containing a dye having a cationic group and an anionic group in a molecule is used as the test liquid.

Description

  The present invention relates to a droplet discharge head inspection method, a droplet discharge head manufacturing method, and a test liquid.

  The ejection characteristics of the droplet ejection head are inspected after the droplet ejection head is manufactured and before shipment. In general, the ejection characteristic inspection of an ejection head for an aqueous ink containing a pigment as a colorant is performed using the aqueous ink. Similarly, a discharge characteristic inspection of a discharge head for a processing liquid containing a flocculant that agglomerates the pigment is generally performed using the processing liquid. For example, as a method for inspecting the ejection characteristics of the treatment liquid ejection head, a method for inspecting the treatment liquid by mixing a phosphor is proposed (Patent Document 1).

JP 2006-88438 A

  As a result of the discharge characteristic inspection of the water-based ink discharge head, when the discharge accuracy is low and it is appropriate to use the treatment liquid discharge head, the discharge characteristic inspection in the discharge head is performed. It is necessary to replace the water-based ink used with the treatment liquid. However, if the aqueous ink remains in the flow path in the ejection head, there is a problem that the flow path is clogged by aggregation of pigments in the aqueous ink due to contact with the treatment liquid. Therefore, a sufficient cleaning operation must be performed using a liquid such as pure water that does not cause aggregation even when contacting with the water-based ink and the treatment liquid so that the water-based ink does not remain in the flow path. These substitutions require a great deal of effort. Further, as a result of performing the ejection characteristic inspection of the treatment liquid ejection head, even when the ejection accuracy is high and the aqueous ink ejection head can be used, for the same reason, a great deal of effort is required for the replacement. Need.

  In view of this, the present invention is a case where the discharge characteristic inspection is to be used as a water-based ink discharge head containing a pigment as a colorant, and a treatment liquid discharge head containing a flocculant for aggregating the pigment. In any case, an object of the present invention is to provide a method for inspecting a droplet discharge head that does not require complicated work.

In order to achieve the above object, an inspection method for a droplet discharge head according to the present invention includes:
A method for inspecting a droplet discharge head that discharges either a water-based ink containing a pigment as a colorant or a treatment liquid containing an aggregating agent that aggregates the pigment,
A test liquid introduction step of introducing a test liquid into the droplet discharge head;
Whether the test liquid is ejected from the droplet ejection head onto a recording medium to inspect ejection characteristics, and whether the droplet ejection head is the water-based ink ejection head or the treatment liquid ejection head And an inspection process for determining
As the test solution, a test solution containing a dye having a cationic group and an anion group in the molecule (hereinafter sometimes referred to as “amphoteric dye”) is used.

  In the method for inspecting a droplet discharge head according to the present invention, the test liquid containing the amphoteric dye that hardly causes aggregation when used with any one of the water-based ink and the processing liquid is used. In both cases where it should be used and when it should be used as the treatment liquid discharge head, no complicated work is required.

FIG. 1 is a diagram for explaining a method for evaluating aggregation in an embodiment of the present invention.

  An inspection method for a droplet discharge head according to the present invention will be described in detail with reference to an example. As described above, the droplet ejection head inspection method of the present invention includes the inspection liquid introduction step and the inspection step.

(Test solution introduction process)
The inspection liquid introduction step is a step of introducing the inspection liquid into the droplet discharge head. The method for inspecting a droplet discharge head of the present invention is characterized in that the inspection liquid of the present invention containing the amphoteric dye is used as the inspection liquid.

  The amphoteric dye is not particularly limited, and examples thereof include C.I. I. Acid Red 52, C.I. I. Acid Red 289, C.I. I. Acid Blue 9, C.I. I. Acid Violet 15, C.I. I. Acid Violet 49, C.I. I. Acid Blue 1, C.I. I. Acid Blue 7, C.I. I. Acid Blue 15, C.I. I. Acid Blue 22, C.I. I. Acid Blue 59, C.I. I. Acid Blue 83, C.I. I. Acid Blue 90, C.I. I. Acid Blue 93, C.I. I. Acid Blue 100, C.I. I. Acid Blue 102, C.I. I. Acid Blue 103, C.I. I. Acid Blue 104, C.I. I. Acid Green 3, C.I. I. Acid Green 9, C.I. I. Acid Green 16, C.I. I. Acid Black 2, Food Blue 2, Food Green 3 and the like.

  The test liquid of the present invention containing the amphoteric dye is less likely to agglomerate when contacted with either a water-based ink containing a pigment as a colorant or a treatment liquid containing a flocculant that aggregates the pigment. Depending on the result of the ejection characteristic inspection, no complicated replacement work is required in both cases where the water-based ink ejection head is to be used and the treatment liquid ejection head is to be used.

  Among the amphoteric dyes mentioned above, C.I. I. Acid Red 52, C.I. I. It is preferable to use a dye that fluoresces when irradiated with ultraviolet rays, such as Acid Red 289. I. It is particularly preferable to use Acid Red 52. If it is the said fluorescent dye, even if it is trace amount, it becomes possible to implement the discharge characteristic test | inspection in the said test | inspection process, and it can make it harder to produce aggregation when the said test liquid contacts the said water-based ink or the said process liquid. The concentration of the fluorescent dye is preferably 0.025 wt% to 0.3 wt%, more preferably 0.1 wt% to 0.3 wt%, based on the total amount of the test solution, Preferably, it is 0.25 wt% to 0.3 wt%.

  The test solution may further contain water. The water is preferably ion exchange water or pure water. The blending amount of water with respect to the total amount of the test solution may be, for example, the remainder of other components.

  The test solution may further contain a water-soluble organic solvent. A conventionally well-known thing can be used as said water-soluble organic solvent. Examples of the water-soluble organic solvent include polyhydric alcohol, polyhydric alcohol derivative, alcohol, amide, ketone, keto alcohol, ether, nitrogen-containing solvent, sulfur-containing solvent, propylene carbonate, ethylene carbonate, 1,3-dimethyl- Examples include 2-imidazolidinone. Examples of the polyhydric alcohol include glycerin, ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, hexylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, trimethylolpropane, 1, Examples include 5-pentanediol and 1,2,6-hexanetriol. Examples of the polyhydric alcohol derivative include ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-n-butyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol-n-propyl ether, Diethylene glycol-n-butyl ether, diethylene glycol-n-hexyl ether, triethylene glycol methyl ether, triethylene glycol ethyl ether, triethylene glycol-n-propyl ether, triethylene glycol-n-butyl ether, propylene glycol methyl ether, propylene glycol ethyl Ether, propylene glycol-n-propyl Ether, propylene glycol-n-butyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol-n-propyl ether, dipropylene glycol-n-butyl ether, tripropylene glycol methyl ether, tripropylene glycol ethyl ether, Examples include tripropylene glycol-n-propyl ether and tripropylene glycol-n-butyl ether. Examples of the alcohol include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, isobutyl alcohol, tert-butyl alcohol, and benzyl alcohol. Examples of the amide include dimethylformamide and dimethylacetamide. Examples of the ketone include acetone. Examples of the keto alcohol include diacetone alcohol. Examples of the ether include tetrahydrofuran and dioxane. Examples of the nitrogen-containing solvent include pyrrolidone, 2-pyrrolidone, N-methyl-2-pyrrolidone, cyclohexyl pyrrolidone, triethanolamine, and the like. Examples of the sulfur-containing solvent include thiodiethanol, thiodiglycol, thiodiglycerol, sulfolane, dimethyl sulfoxide and the like. The blending amount of the water-soluble organic solvent with respect to the total amount of the test solution is not particularly limited. The water-soluble organic solvent may be used alone or in combination of two or more.

  The test solution may further contain a conventionally known additive as required. Examples of the additive include a surfactant, a viscosity modifier, a surface tension modifier, an antioxidant, and an antifungal agent. Examples of the viscosity modifier include polyvinyl alcohol, cellulose, and a water-soluble resin.

  The inspection liquid may be introduced into the droplet discharge head by a conventional method. For example, when the droplet discharge head is a piezo-type droplet discharge head, an ink cartridge for a general ink jet recording apparatus is filled with the inspection liquid, and the ink cartridge and the piezo are stored in the ink jet recording apparatus. The inspection liquid can be introduced into the piezo-type droplet discharge head by mounting the droplet-type droplet discharge head and operating the inkjet recording apparatus. For example, when the droplet discharge head is a thermal inkjet droplet discharge head, the test liquid can be introduced in the same manner.

(Inspection process)
In the inspection step, the inspection liquid is discharged from the droplet discharge head onto a recording medium to inspect discharge characteristics, and the droplet discharge head is used as the water-based ink discharge head, or the treatment liquid is used. This is a step of determining whether to use an ejection head.

  The inspection liquid may be discharged from the droplet discharge head onto the recording medium by a conventional method. For example, the inspection liquid can be discharged from the droplet discharge head onto a recording medium by continuing the operation of the ink jet recording apparatus after the inspection liquid is introduced into the droplet discharge head.

  The method for inspecting the ejection characteristics is not particularly limited, and examples thereof include a fluorescent inspection and a visual inspection.

  First, the ejection characteristic inspection using fluorescence will be described. In the discharge characteristic inspection by fluorescence, as the amphoteric dye, a dye that emits fluorescence by ultraviolet irradiation is used. In this step, the recording medium on which the test liquid is discharged is irradiated with ultraviolet light, and the fluorescence generated by the irradiation is used. The discharge characteristics are inspected.

  The kind and density | concentration of the said fluorescent dye are as having demonstrated in the said test liquid introduction process.

  Next, in the visual ejection characteristic inspection, for example, the concentration of the amphoteric dye with respect to the entire test liquid is 0.1 wt% to 0.25 wt%, and the ejection characteristics are visually inspected in this step. According to the visual inspection, the ejection characteristics can be easily inspected without requiring the recording medium to be irradiated with ultraviolet rays.

  The method for determining whether to use the water-based ink discharge head or the treatment liquid discharge head is not particularly limited. For example, the discharge accuracy in the discharge characteristic inspection (for example, the degree of non-discharge and discharge bending) Etc.) is determined in advance, and those having high discharge accuracy are the water-based ink discharge heads, and those having low discharge accuracy are the processing liquid discharge heads. The non-ejection is a state in which the nozzle of the droplet ejection head is clogged and the inspection liquid is not ejected. The ejection bend is a state in which a part of the nozzles of the droplet ejection head is clogged and the inspection liquid is ejected obliquely without being ejected perpendicularly to the recording medium. The judgment criteria are three stages of high, medium and low, and those having high discharge accuracy are the water-based ink discharge heads, and those having medium discharge accuracy are the treatment liquid discharge heads, and the discharge accuracy is high. It is possible to determine that the low one is not suitable for either the water-based ink discharge head or the treatment liquid discharge head.

  In the method for inspecting a droplet discharge head according to the present invention, an inspection liquid containing the amphoteric dye that hardly causes aggregation when used in contact with either the water-based ink or the processing liquid is used. For this reason, in any of the case where it is determined that the water-based ink discharge head is suitable and the case where it is determined that the water-based ink discharge head is suitable, the liquid droplet discharge head in the liquid droplet discharge head It is possible to directly replace the inspection liquid with the water-based ink or the processing liquid without replacing with another liquid such as pure water. The replacement can be performed, for example, by discharging the inspection liquid in the droplet discharge head by suction purge and then introducing the water-based ink or the processing liquid. In addition, after the purge of the inspection liquid, a preserving liquid for preserving the channel at the time of shipment is introduced, and then the preserving liquid is replaced with the water-based ink or the processing liquid by a user operation. Good. Also in this case, aggregation does not occur even when a special treatment is not performed at the time of introducing the preservative solution and at the time of replacement with the water-based ink or the treatment solution.

  Next, a method for manufacturing the droplet discharge head of the present invention will be described. The manufacturing method of the droplet discharge head of the present invention includes an inspection process of the manufactured droplet discharge head, and the inspection process is performed by the inspection method of the droplet discharge head of the present invention. The method for manufacturing a droplet discharge head according to the present invention is characterized by performing the method for inspecting a droplet discharge head according to the present invention, and other processes and conditions are not limited at all. For the manufacturing method of the droplet discharge head of the present invention, for example, the description of the aforementioned inspection liquid of the present invention and the inspection method of the droplet discharge head of the present invention can be cited.

  Next, examples of the present invention will be described together with comparative examples. In addition, this invention is not limited and restrict | limited by the following Example and comparative example.

[Examples 1-7 and Comparative Examples 1-3]
Each component of the test liquid composition (Table 3) was uniformly mixed to obtain test liquids of Examples 1 to 7 and Comparative Examples 1 to 3.

  For the test solutions of Examples and Comparative Examples, (a) aggregation evaluation, (b) visual discharge characteristic evaluation, and (c) fluorescent discharge characteristic evaluation were performed by the following methods.

(A) Aggregation evaluation (preparation of treatment liquid)
Each component of the treatment liquid composition (Table 1) was uniformly mixed to obtain a treatment liquid.
(Table 1)
Ingredient Amount (wt%)
PAA (registered trademark) -3 (* 2) 15.00
Polyethylene glycol # 200 21.50
Dipropylene glycol-n-propyl ether 1.00
Mydoll 10 (* 3) 1.00
Acetic acid 2.00
Benzotriazole 0.10
Pure water balance * 2: Polyallylamine unneutralized product (weight average molecular weight 3000); manufactured by Nitto Boseki Co., Ltd .; active ingredient amount = 20 wt%; Activator; manufactured by Kao Corporation

(Preparation of water-based ink)
In the aqueous ink composition (Table 2), components other than the pigment aqueous dispersion were uniformly mixed to obtain an ink solvent. Next, the ink solvent was added to the aqueous dispersion of the pigment and mixed uniformly. Thereafter, the obtained mixture was filtered with a cellulose acetate type membrane filter (pore size: 3.00 μm) manufactured by Toyo Roshi Kaisha, Ltd., to obtain an aqueous ink for inkjet recording.
(Table 2)
Ingredient Amount (wt%)
Cab-O-Jet (registered trademark) 300 (* 4) 40.0
Glycerin 28.0
Dipropylene glycol-n-propyl ether 2.0
Olphine (registered trademark) E1010 (* 1) 0.2
Pure water remainder * 4: Pigment aqueous dispersion; manufactured by Cabot Specialty Chemicals; pigment concentration = 1
0% by weight
* 1: Acetylene glycol surfactant (diol ethylene oxide (10mo
l) Additives; manufactured by Nissin Chemical Industry Co., Ltd.

  As shown in FIG. 1 (A), the test liquid 12 of the example or the comparative example and the treatment liquid 13 were dropped on the slide glass 11 by 1 drop (about 0.02 mL). Next, as shown in FIG. 1B, the two liquids dropped were covered with a cover glass 14, thereby bringing the two liquids into contact with each other. The two-liquid interface 15 of the prepared slide was observed with an optical microscope (200 times). Moreover, it replaced with the said process liquid and performed the same process using the said water-based ink for inkjet recording. These results were evaluated according to the following evaluation criteria.

Aggregation Evaluation Evaluation Criteria G: No agglomerates were generated at the interface 15 between the two liquids in any of the treatment liquid and the water-based ink.
NG: Aggregates were formed at the interface 15 between the two liquids in either or both of the treatment liquid and the water-based ink.

(B) Visual evaluation of ejection characteristics (a) A test liquid whose aggregation evaluation result was “G” was introduced into a line type liquid droplet ejection head mounted on an ink jet recording apparatus, and recording was performed using the test liquid. An image quality evaluation pattern was recorded on the medium. The image quality evaluation pattern was visually observed, and the ejection characteristics of the line type liquid droplet ejection head were evaluated according to the following evaluation criteria.

Visual evaluation of ejection characteristics Evaluation criteria A: Both non-ejection and ejection bending of the line-type droplet ejection head could be confirmed.
B: Non-ejection of the line type liquid droplet ejection head could be confirmed, but ejection bending could not be confirmed.
C: Both non-ejection and ejection bending of the line type droplet ejection head could not be confirmed.

(C) Evaluation of ejection characteristics by fluorescence (a) A test liquid whose aggregation evaluation result was “G” was introduced into a line type liquid droplet ejection head mounted on an ink jet recording apparatus, and recording was performed using the test liquid. An image quality evaluation pattern was recorded on the medium. The image quality evaluation pattern was irradiated with ultraviolet rays, and the ejection characteristics of the line type droplet ejection head were evaluated according to the following evaluation criteria.

Evaluation of discharge characteristics by fluorescence Evaluation criteria A: It was possible to confirm both non-discharge and discharge bending of the line type liquid droplet discharge head.
B: Non-ejection of the line type liquid droplet ejection head could be confirmed, but ejection bending could not be confirmed.
C: Both non-ejection and ejection bending of the line type droplet ejection head could not be confirmed.

  Table 3 shows the compositions and evaluation results of the test solutions of Examples 1 to 7 and Comparative Examples 1 to 3.

  As shown in Table 3, C.I. I. Acid Red 52, C.I. I. Acid Red 289 or C.I. I. In Examples 1 to 7 using the test liquid containing Acid Blue 9, the test liquid does not aggregate when it comes into contact with either the processing liquid or the water-based ink, and the discharge characteristics of the liquid droplet discharge head visually. Inspection was possible. In Examples 1, 4 and 6 in which the concentration of the amphoteric dye was 0.25% by weight or more, the visual evaluation of the ejection characteristics was particularly preferable. Furthermore, C.I. is an amphoteric dye that emits fluorescence when irradiated with ultraviolet rays. I. Acid Red 52 or C.I. I. In Examples 1 to 5 using the test liquid containing Acid Red 289, it was possible to perform a discharge characteristic test using fluorescence of the droplet discharge head. Further, in Examples 1 to 7 using the test liquid containing the amphoteric dye, as described above, no aggregation occurs even when contacted with either the treatment liquid or the water-based ink. The inspection liquid in the line type liquid droplet ejection head could be easily replaced with the processing liquid and the water-based ink. On the other hand, in Comparative Examples 1 to 3 using a test liquid containing a dye that is not the amphoteric dye, the test liquid comes into contact with one or both of the treatment liquid and the water-based ink, and a droplet discharge head The discharge characteristic inspection could not be carried out.

  As described above, in the method for inspecting a droplet discharge head according to the present invention, the test solution containing the amphoteric dye that hardly causes aggregation even when contacting with either the water-based ink or the treatment liquid is used. In either case of using as a water-based ink discharge head or in the case of using as a treatment liquid discharge head, no complicated replacement work is required. The method for inspecting a droplet discharge head according to the present invention is widely applicable to various ink jet recordings.

11 Slide glass 12 Inspection liquid 13 Treatment liquid (water-based ink)
14 Cover glass 15 Interface

Claims (11)

A method for inspecting a droplet discharge head that discharges either a water-based ink containing a pigment as a colorant or a treatment liquid containing an aggregating agent that aggregates the pigment,
A test liquid introduction step of introducing a test liquid into the droplet discharge head;
Whether the test liquid is ejected from the droplet ejection head onto a recording medium to inspect ejection characteristics, and whether the droplet ejection head is the water-based ink ejection head or the treatment liquid ejection head And an inspection process for determining
An inspection method for a droplet discharge head, wherein an inspection liquid containing a dye having a cation group and an anion group in a molecule is used as the inspection liquid. The dye is a fluorescent dye that emits fluorescence when irradiated with ultraviolet rays;
2. The inspection of a droplet discharge head according to claim 1, wherein, in the inspection step, the recording medium on which the inspection liquid is discharged is irradiated with ultraviolet rays, and the discharge characteristics are inspected by fluorescence generated by the irradiation. Method. 3. The method for inspecting a droplet discharge head according to claim 2, wherein the concentration of the fluorescent dye is 0.025 wt% to 0.3 wt% with respect to the entire inspection liquid. The fluorescent dye is C.I. I. 4. The method for inspecting a droplet discharge head according to claim 2, further comprising: Acid Red 52. The concentration of the dye with respect to the entire test solution is 0.1 wt% to 0.25 wt%,
The method for inspecting a droplet discharge head according to claim 1, wherein in the inspection step, the ejection characteristics are inspected visually. A method of manufacturing a droplet discharge head,
Including the inspection process of the manufactured droplet discharge head,
A method for manufacturing a droplet discharge head, wherein the inspection step is performed by the method according to claim 1. An inspection liquid used in the inspection method for a droplet discharge head according to claim 1,
A test liquid comprising a dye having a cationic group and an anionic group in a molecule. The dye is a fluorescent dye that emits fluorescence when irradiated with ultraviolet rays;
8. The inspection liquid according to claim 7, wherein in the inspection step, the recording medium on which the inspection liquid is discharged is irradiated with ultraviolet rays, and the discharge characteristics are inspected by fluorescence generated by the irradiation. The test solution according to claim 8, wherein the concentration of the fluorescent dye is 0.025 wt% to 0.3 wt% with respect to the entire test solution. The fluorescent dye is C.I. I. The test liquid according to claim 8, comprising acid red 52. The concentration of the dye with respect to the entire test solution is 0.1 wt% to 0.25 wt%,
The inspection liquid according to claim 7, wherein in the inspection step, the ejection characteristics are inspected visually.

Images