JP2019119844A - Curing liquid composition, composition housing container, liquid composition discharge device, cured article, and manufacturing method of cured article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curable liquid composition which has no problem in skin sensitization and sufficiently reduces a peculiar odor immediately after photopolymerization. A curable liquid composition of the present invention contains a monomer having an SI value of less than 3.0 and a photopolymerization initiator having a weight average molecular weight of 500 or more, and is a curable liquid having a negative skin sensitization property. It is a composition. As the photopolymerization initiator, a photopolymerization initiator having a chemical structure containing a phenylglycolate skeleton and / or a photopolymerization initiator having a chemical structure containing a benzophenone skeleton is preferable. [Selection diagram] None

Description

  The present invention relates to a curable liquid composition, a composition containing container, a liquid composition discharge device, a cured product, and a method for producing the cured product.

  Although photopolymerizable compositions and ink jet inks containing an acrylic ester compound as a main component are widely known (see Patent Document 1), many of the acrylic ester compounds cause skin feeling that causes swelling, itching, etc. when they come in contact with the skin. It has operability. After polymerization by appropriate light irradiation, the acrylic acid ester compound becomes higher in molecular weight, so the skin sensitization is reduced, and there is little influence on consumers touching it, etc., but the composition and ink before light irradiation are handled The worker has a problem in safety.

On the other hand, it has been found that skin sensitization can be improved by using a methacrylic acid ester compound instead of an acrylic acid ester compound, but a distinctive odor immediately after photopolymerization is generated due to the photopolymerization initiator used, and the skin Even if there is no problem in the sensitization, it has not been sufficiently considered by the workers who handle the composition and the ink before the light irradiation, in terms of unpleasantness due to the offensive odor.
Therefore, there is no problem in skin sensitization and the practical application of a photopolymerizable composition and an ink jet ink sufficiently reduced with respect to a specific odor immediately after photopolymerization for consideration to workers handling the ink before light irradiation. It is expected.

  In addition, although the system which uses water and an organic solvent as a photopolymerizable composition and inkjet ink also exists, since a heat source etc. are required in order to evaporate water and an organic solvent in these cases, it is unpreferable from an energy saving viewpoint. Therefore, it is desirable not to contain water or organic solvents.

  It is an object of the present invention to provide a curable liquid composition which has no problem in skin sensitization and which has sufficiently reduced the characteristic odor immediately after curing.

The above problem is solved by the invention of the following 1).
1) A curable liquid composition containing a monomer having an SI value of less than 3.0 and a photopolymerization initiator having a weight average molecular weight of 500 or more and having negative skin sensitization.

  According to the present invention, it is possible to provide a curable liquid composition which has no problem in skin sensitization and which has sufficiently reduced the specific odor immediately after curing.

FIG. 2 is an external perspective view of a liquid discharge head according to an embodiment of the present invention. It is a section explanatory view of the direction which intersects perpendicularly with the nozzle arrangement direction of the head. It is partial cross section explanatory drawing of the direction parallel to the nozzle arrangement direction of the head. It is plane explanatory drawing of the nozzle plate of the head. It is plane explanatory drawing of each member which comprises the flow-path member of the head. It is plane explanatory drawing of each member which comprises the common liquid chamber member of the head. It is a block diagram showing an example of a fluid circulation system concerning the present invention. It is an AA 'cross section figure of FIG. It is a BB 'cross section figure of FIG. It is principal part plane explanatory drawing of an example of the apparatus which discharges the liquid which concerns on this invention. It is principal part side explanatory drawing of the same apparatus. It is principal part plane explanatory drawing of the other example of the liquid discharge unit which concerns on this invention. FIG. 6 is a schematic view showing an example of an ink bag of an ink cartridge. FIG. 6 is a schematic view showing an example of an ink cartridge containing an ink bag. It is the schematic of an example of a liquid composition discharge apparatus.

Hereinafter, the present invention will be described in detail.
JP-A-2014-237804 proposes a photopolymerizable ink jet ink having no problem in skin sensitization. However, when a low molecular weight one such as 1-hydroxy-cyclohexyl-phenyl-ketone (molecular weight 204) is used as a photopolymerization initiator, the generation of by-products as shown below is generally known. This is the cause of the distinctive odor.

As described above, in the photo initiation reaction, not only the target reaction but also the side reaction proceeds, and it is difficult to completely prevent the generation of the side reaction product, but a photopolymerization initiator having a weight average molecular weight of 500 or more By using it, even if a side reaction product is generated as described above, it is difficult to volatilize because it has a sufficiently high molecular weight, and the characteristic odor immediately after photopolymerization can be significantly reduced. As a result, it is possible to provide a curable liquid composition in which the operator is considered in terms of skin sensitization and odor.
In the present invention, the liquid composition refers to a composition which is liquid at room temperature. Hereinafter, the curable liquid composition is sometimes referred to as "curable composition" or "composition".
The skin sensitization is more pronounced for low molecular weight ones because the substance passes through the skin, so the problem of skin sensitization becomes greater for low molecular weight or low viscosity ones. Furthermore, since the use of a high molecular weight initiator makes the viscosity high during dissolution prominently, the viscosity of the curable composition is reduced to a level suitable for inkjet ink applications in terms of skin sensitization and odor. Although this is a more difficult task, optimization of the formulation makes this feasible.

  The skin sensitization as a composition is determined by the skin sensitization of the raw materials used in the composition, and in the concept of GHS, which is the global standard, skin sensitization as a mixture containing 0.1% or more of skin sensitizers It is defined as a productive substance. For this reason, constituting the composition that is substantially skin sensitizing negative results in making the composition skin sensitizing negative. For monomers, if the SI value is less than 3.0, the skin sensitization is negative. The SI value is evaluated in the manner as shown in the examples.

  Skin sensitization starts with the passage of chemicals through the skin barrier. For this reason, the smaller the molecular weight chemical substance, the more likely skin sensitization is noticeable, and the composition composed of a lower molecular weight chemical substance, that is, the lower viscosity composition, makes it more difficult to make the skin sensitization negative. Become. Therefore, it is difficult to achieve negative skin sensitization negative as the composition has a lower viscosity, and in particular, to achieve negative skin sensitization as a curable composition having a viscosity of 1000 mPa · s or less at 25 ° C. Is a difficult task.

(Monomer with SI value less than 3.0)
In the present invention, a monomer having an SI value of less than 3.0 is used as a component of the composition.
Examples of the monomer having an SI value of less than 3.0 and having no problem with skin sensitization include photopolymerizable monomers such as (meth) acrylic acid ester compounds which are inexpensive and easily available. For example, diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate [CH ₂ CC (CH ₃ ) -CO- (OC ₂ H ₄ ) n -OCOC (CH ₃ ) = CH ₂ (n is an average degree of polymerization, here 2 or more) Γ-butyrolactone methacrylate, trimethylolpropane trimethacrylate, ethylene oxide modified trimethylolpropane trimethacrylate, propylene oxide modified trimethylolpropane trimethacrylate, tricyclodecanedimethanol dimethacrylate, caprolactone modified dipentaerythritol hexaacrylate, polypropylene glycol di Acrylate [CH ₂ CHCH—CO— (OC ₃ H ₆ ) n —OCOCH = CH ₂ (n is an average degree of polymerization, here 12 or more)], caprolactone Tonally modified hydroxypivalate neopentyl glycol diacrylate, ethylene oxide modified tetramethylol methane tetraacrylate, ethylene oxide modified bisphenol A diacrylate, neopentyl glycol dimethacrylate, stearyl acrylate, isostearyl acrylate, 1,4-butanediol dimethacrylate, Hydroxyethyl acrylamide, glycerol dimethacrylate and glycerol monomethacrylate, etc. may be mentioned.
It is preferable to include a hydroxyl group-containing monomer as the monomer.
Glycerol dimethacrylate and glycerol monomethacrylate contain hydroxyl groups and improve the adhesion to inorganic substrates, especially to glass.

Further, if necessary, for example, the following single substances have some problems in skin sensitization, etc., and it is also possible to use (meth) acrylates, (meth) acrylamides and vinyl compounds whose skin sensitization is not confirmed. it can. These monomers are used in such a content that the skin sensitization of the composition containing them is negative.
Ethylene glycol di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, γ-butyrolactone acrylate, formalized trimethylolpropane mono (meth) acrylate, polytetramethylene glycol di (meth) acrylate, trimethylolpropane ( (Meth) acrylic acid benzoate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate [CH ₂ = CH-CO- (OC ₂ H ₄ ) n -OCOCH = CH ₂ (n 9 9), same (n 14 14), same (n 23 23)], dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, poly Propylene glycol dimethacrylate [CH ₂ CC (CH ₃ ) —CO— (OC ₃ H ₆ ) n —OCOC (CH ₃ ) = CH ₂ (n77)], 1,3-butanediol diacrylate, 1 2,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, propylene oxide modified bisphenol A di (Meth) acrylate, polyethylene glycol di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, (meth) acryloyl morpholine, 2-hydroxypropyl (meth) acrylamide, propylene oxide modified tetramethylol methane tetra (meth) acrylate, Pentaerythritol hydroxypenta (meth) acrylate, caprolactone modified dipentaerythritol hydroxypenta (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, trimethylolpropane triacrylate, ethylene oxide modified trimethylolpropane Triacrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate, caprolactone modified trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, ethoxy Neopentyl glycol di (meth) acrylate, propylene oxide Id-modified neopentyl glycol di (meth) acrylate, propylene oxide modified glyceryl tri (meth) acrylate, polyester di (meth) acrylate, polyester tri (meth) acrylate, polyester tetra (meth) acrylate, polyester penta (meth) acrylate, polyester Poly (meth) acrylate, (meth) acryloyl morpholine, hydroxyethyl (meth) acrylamide, N-vinylcaprolactam, N-vinyl pyrrolidone, N-vinyl formamide, polyurethane di (meth) acrylate, polyurethane tri (meth) acrylate, polyurethane tetra (Meth) acrylate, polyurethane penta (meth) acrylate, polyurethane poly (meth) acrylate, triethylene glycol di Vinyl ether, cyclohexane dimethanol divinyl ether, cyclohexane dimethanol monovinyl ether, hydroxyethyl vinyl ether, diethylene glycol monovinyl ether, diethylene glycol divinyl ether, dicyclopentadiene vinyl ether, tricyclodecane vinyl ether, benzyl vinyl ether, ethyl oxetane methyl vinyl ether, triethylene glycol divinyl ether Hydroxybutyl vinyl ether, ethyl vinyl ether and the like.

(Photopolymerization initiator)
In the present invention, a photopolymerization initiator having a weight average molecular weight of 500 or more is used as a composition component.
As a photoinitiator, it is preferable to use a radical photopolymerization initiator. As the photo radical polymerization initiator, one having a negative skin sensitization is preferably used, but when the skin sensitization of a photo polymerization initiator is not negative, the skin sensitization of a curable composition is The photopolymerization initiator is used in a concentration range that makes it negative. However, when the molecular weight of the photopolymerization initiator is too large, although it is good in terms of skin sensitization, the spinnability characteristic of a polymer solution is developed as a liquid, and in particular in the use of an ink jet, the discharged liquid is It does not fly normally and it leads to the disorder of the image by tailing for a long time. When such a thing is also considered, the weight average molecular weight of a photoinitiator is preferably 10000 or less.

  Although (meth) acrylic esters, (meth) acrylamides and derivatives thereof, and vinyl ether compounds are known to have ionic polymerizability, ionic polymerization initiators are generally not only expensive but also do not irradiate light. In order to generate a strong acid / alkali slightly even in the condition, special consideration such as acid resistance / alkali resistance is required in the composition supply path in the liquid discharge system. Therefore, the selection of the members constituting the liquid discharge system is restricted. On the other hand, in the composition of the present invention, since it is possible to use an optical radical polymerization initiator which is inexpensive and does not generate a strong acid or a strong alkali, the composition can be manufactured at low cost. It becomes easy. Of course, in the case of using a high energy light source such as an electron beam or α, β, γ or X ray, the polymerization reaction can be advanced without using a polymerization initiator, but this is generally more than before As it is known and the equipment is very expensive, it will not be described in detail in the present invention.

  The content of the photopolymerization initiator in the composition is preferably low in cost, but if it is desired to cure with a smaller amount of light, many photopolymerization initiators which are radical generation sources can be blended. However, when the content of the photopolymerization initiator is increased, the viscosity of the composition is increased and the cost is increased. Therefore, the composition can be appropriately determined in the range in which the viscosity of the composition is not increased.

  Further, the larger the molecular weight, the more preferable it is because the photopolymerization initiator is difficult to volatilize. However, the larger the molecular weight, the higher the viscosity when incorporated in the composition. Therefore, the weight average molecular weight of the photopolymerization initiator is more preferably 2000 or less.

The photopolymerization initiator is preferably a polymer in a liquid state. By being in the liquid state, it can be uniformly dispersed in the composition.
As the photopolymerization initiator, a photopolymerization initiator having a chemical structure containing a phenylglyoxylate skeleton, a photopolymerization initiator having a chemical structure containing a benzophenone skeleton, or a photopolymerization initiator having a chemical structure containing a nitrogen atom is used Is preferred.
A photopolymerization initiator having a chemical structure containing a phenylglyoxylate skeleton and a photopolymerization initiator having a chemical structure containing a benzophenone skeleton start polymerization with short wavelength light, and there is no coloring, so they are clear not containing coloring materials. Suitable for the composition.
In addition, a photopolymerization initiator having a chemical structure containing a nitrogen atom is suitable for a composition containing a coloring material because it causes polymerization to be initiated by long wavelength light and some coloring occurs.

  As a photoinitiator, it is a polymer shown by following Structural formula, Comprising: The thing of weight average molecular weight 500 or more can be mentioned.

C1: Polybutylene glycol-bis-phenylglyoxylate

C2: diester of polytetramethylene glycol and carboxymethoxybenzophenone

C3: Diester of polyethylene glycol and carboxybenzophenone

C4: polyethylene glycol-bis-dimethylaminobenzoate

C5: diester of polytetramethylene glycol and carboxymethoxythioxanthone

C6: polyethylene glycol-di- (β-4 [4- (2-dimethylamino-2-benzyl) butanoylphenyl] piperazine) propionate

In addition, as described above, from the viewpoint of not only low odor but also good curability and adhesion to a glass substrate, a photopolymerization initiator having a molecular weight of 500 or more with respect to 100 parts by mass of the total amount of monomer components. It is preferable to contain 10 parts by mass or more and 31 parts by mass or less. In the case of containing a coloring material, it is preferable to contain 3 parts by mass or more and 30 parts by mass or less of a photopolymerization initiator containing a nitrogen atom and having a molecular weight of 500 or more based on 100 parts by mass of the total amount of monomer components. Within this range, the color tone is not adversely affected.
Moreover, although it is preferable to mix many photoinitiators with a molecular weight of 500 or more in order to obtain sufficient curability, from the viewpoint of preventing the viscosity of the liquid from increasing, the total amount of monomer components is 100 parts by mass. It is desirable to use 30 parts by mass or less.
In addition, a photopolymerization initiator having a molecular weight of less than 500 can be used in a range not causing a problem in view of low bromide, and it is desirable that the amount be 5 parts by mass or less with respect to 100 parts by mass of the total amount of monomers.
Moreover, it is preferable to contain 50 mass parts or more and 95 mass parts or less of monomers having an SI value of less than 3.0 with respect to 100 mass parts of the total amount of the liquid composition.

(Color material)
If necessary, the composition may be a clear composition not containing a coloring material, or may be a coloring composition containing a coloring material. When it is desired to use a clear composition that is desired to be colorless and transparent, or when it is desired to maintain the color tone of the coloring material itself as much as possible, materials other than the coloring materials described above or below It is desirable to use.

When the composition contains a colorant as required, known inorganic pigments and organic pigments can be used as the colorant of the composition.
As the black pigment, carbon black produced by the furnace method or the channel method can be used.
As yellow pigments, Pig. Yellow pigments such as pigment yellow 1, pigment yellow 2, pigment yellow 3, pigment yellow 12, pigment yellow 13, pigment yellow 14, pigment yellow 16, pigment yellow 17, pigment yellow 73, pigment yellow 74, pigment yellow 75, Pigment yellow 83, pigment yellow 93, pigment yellow 95, pigment yellow 97, pigment yellow 98, pigment yellow 114, pigment yellow 120, pigment yellow 128, pigment yellow 129, pigment yellow 138, pigment yellow 150, pigment yellow 151, pigment yellow 154, pigment yellow 155, pigment yellow 180, etc. It can be used.

As magenta pigments, Pig. Red pigments such as Pigment Red 5, Pigment Red 7, Pigment Red 12, Pigment Red 48 (Ca), Pigment Red 48 (Mn), Pigment Red 57 (Ca), Pigment Red 57: 1, Pigment Red 112, Pigment Red 122, pigment red 123, pigment red 168, pigment red 184, pigment red 202, pigment violet 19 and the like can be used.
As cyan pigments, Pig. Blue-based pigments such as pigment blue 1, pigment blue 2, pigment blue 3, pigment blue 15, pigment blue 15: 3, pigment blue 15: 4, pigment blue 16, pigment blue 22, pigment blue 60, bat blue 4, Bat Blue 60 etc. can be used.
As white pigments or colorless fillers for modifying physical properties, sulfates of alkaline earth metals such as barium sulfate, carbonates of alkaline earth metals such as calcium carbonate, finely powdered silicic acid, synthetic silicates, etc. Silicas, calcium silicate, alumina, alumina hydrate, titanium oxide, zinc oxide, talc, clay and the like can be used.
In addition, various inorganic pigments and organic pigments can be used as necessary in consideration of physical properties and the like.

  Furthermore, if necessary, 4-methoxy-1-naphthol, methylhydroquinone, hydroquinone, t-butylhydroquinone, di-t-butylhydroquinone, methoquinone, 2,2'-dihydroxy-3,3'-di (α- Methylcyclohexyl) -5,5'-dimethyldiphenylmethane, p-benzoquinone, di-t-butyldiphenylamine, 9,10-di-n-butoxycyanthracene, 4,4 '-[1,10-dioxo-1,10 -Polymerization inhibitors such as decanediylbis (oxy)! Bis [2,2,6,6-tetramethyl] -1-piperidinyloxy, polyether, higher fatty acid ester having amino group, carboxyl group, hydroxyl group, side Polydimethyl silicone having polyether, amino group, carboxyl group, hydroxyl group at chain or end Emissions compounds, polyethers, amino group, carboxyl group, a surfactant or the like fluoroalkyl compound having a hydroxyl group can be used such as a polar group-containing polymeric pigment dispersant.

The application of the curable composition of the present invention is not particularly limited as long as the curable material is generally used, and can be appropriately selected according to the purpose. For example, resin for molding, paint, adhesive And insulating materials, mold release agents, coating materials, sealing materials, various resists, various optical materials and the like.
Furthermore, the curable composition of the present invention is used as an ink to form not only two-dimensional characters and images, and a design coating film on various substrates, but also forms a three-dimensional three-dimensional image (three-dimensional object) It can also be used as a material for three-dimensional modeling.
As a three-dimensional shaping apparatus for shaping a three-dimensional object by using the curable composition of the present invention, known devices can be used, and it is not particularly limited. For example, means for containing the composition, means for supplying the composition And discharge means, active energy ray irradiation means and the like.
The present invention also includes a cured product obtained by curing the curable composition, and a molded and processed product obtained by processing a structure having the cured product formed on a substrate. The molded product is, for example, a cured product or a structure formed into a sheet or a film and is subjected to a forming process such as heat drawing or punching. For example, an automobile, an OA apparatus, an electric machine It is suitably used for applications that require shaping after decorating, such as electronic devices, meters such as cameras, and panels of operation parts.

(Composition container)
The composition-containing container of the present invention means a container in which the curable composition is contained, and is suitable for use in the above-described applications. For example, when the curable composition of the present invention is used for ink, the container in which the ink is stored can be used as an ink cartridge or an ink bottle. There is no need to directly touch the ink, and it is possible to prevent stains on fingers and clothes. In addition, it is possible to prevent mixing of foreign matter such as dust into the ink. Further, the shape, size, material, etc. of the container itself may be any suitable one for use and usage, and is not particularly limited. However, the material is a light shielding material which does not transmit light, or the container It is desirable to be covered with a sex sheet etc. For example, one having an ink bag or the like formed of an aluminum laminate film, a resin film or the like is preferable.

The ink cartridge will be described with reference to FIGS. 13 and 14. FIG. 13 is a schematic view showing an example of the ink bag 241 of the ink cartridge, and FIG. 14 is a schematic view showing the ink cartridge 200 in which the ink bag 241 of FIG.
As shown in FIG. 13, the ink is filled into the ink bag 241 from the ink injection port 242, and after the air remaining in the ink bag is exhausted, the ink injection port 242 is closed by fusion. At the time of use, the needle of the apparatus main body is pierced through the ink discharge port 243 made of a rubber member and supplied to the apparatus. The ink bag 241 is formed of a packaging member such as an air-impermeable aluminum laminate film. Then, as shown in FIG. 14, normally, the ink cartridge 200 is housed in a plastic cartridge case 244, and is detachably mounted on various liquid ejection devices as the ink cartridge 200.
The composition storage container of the present invention is preferably removable from the liquid discharge device. Thereby, the replenishment and replacement of the composition can be simplified, and the workability can be improved.

(Liquid composition discharge device)
FIG. 15 shows a schematic view of an example of a liquid ejection apparatus (printing apparatus) using the composition as an ink.
FIG. 15 shows the printing substrate supplied from the printing substrate supply roll 21 by each of the printing units 23 [consisting of printing units 23a, 23b, 23c, 23d of each color (for example, yellow, magenta, cyan, black)]. Each time printing of each color (yellow, magenta, cyan, black) discharged to the substrate 22 (conveyed from left to right in the figure), light irradiation (UV) from an ultraviolet light source (light source for curing) 24a, 24b, 24c, 24d It shows an example in which light is cured to form a color image.
Plastic, metal or the like is used as the printing substrate 22, but the most effective ink is polypropylene and polyethylene terephthalate. Moreover, although the roll-shaped to-be-printed base material 22 is shown in FIG. 15, the shape required for every sheet form or a use may be sufficient. Furthermore, not only single-sided printing but also double-sided printing may be performed.
Higher speed of curing can be obtained by irradiating with ultraviolet rays each time each color is printed in order to speed up printing, but multiple colors are printed by, for example, weakening or omitting the ultraviolet light sources 24a, 24b, and 24c. It was later put together and cured by irradiating a sufficient amount of ultraviolet light by 24d, or in place of a light source conventionally used such as a high pressure mercury lamp and a metal halide lamp, it was put into practical use for photopolymerizable ink printing in recent years. By introducing an LED light source, energy saving and cost reduction can be achieved.
In the figure, reference numeral 25 denotes a processing unit, and reference numeral 26 denotes a printed matter take-up roll. Although not shown, the printing unit accommodates an ink or ink cartridge and supplies the ink stably at the time of printing.

Further, as the discharge head, there are a plurality of nozzles for discharging liquid, individual liquid chambers communicating with the nozzles, a common liquid chamber for supplying the liquid to the individual liquid chambers, and a circulation flow path connecting to the individual liquid chambers. It is preferable to comprise a circulation common liquid chamber communicating with the circulation channel, and a pressure generating means for applying pressure to the liquid in the individual liquid chamber.
When the composition of the present invention is used as an ink, it is preferable to use a flow-through type ink in which the ink circulates in the individual liquid chamber of the discharge head. The circulation of the ink can be performed not only during the operation of the ink discharge head but also during the ink discharge. By circulating at the time of operation stop, the ink in the individual liquid chamber is always refreshed, and aggregation and sedimentation of the components contained in the ink can be suppressed, which is preferable.
The photopolymerization initiator having a molecular weight of 500 or more often has a polyalkylene glycol structure, and by including this, the hydrophilicity of the composition becomes high. If a mechanism for circulating and maintaining the ink in the head is provided, the ink jet head is left exposed for a long time under, for example, a high temperature and high humidity environment, and the ink near the nozzle surface contains a large amount of water. It is possible to obtain a stable discharge state immediately after leaving without causing the stable dispersed state to break down.
When the composition of the present invention is used as a white ink, titanium oxide particles used as a pigment tend to settle due to high specific gravity, and when the liquid is in a stationary state, it tends to generate a nozzle clog. This can be prevented, and the maintenance operation can be simplified particularly in the recovery from discharge suspension and the like.

A liquid discharge apparatus provided with a flow-through type discharge head will be described based on FIGS. 1 to 12.
First, an embodiment of the present invention will be described with reference to the attached drawings. An example of a liquid discharge head according to an embodiment of the present invention will be described with reference to FIGS. 1 to 6. 1 is an external perspective view of the liquid discharge head, FIG. 2 is an explanatory sectional view of the head in the direction perpendicular to the nozzle arrangement direction, and FIG. 3 is an explanatory sectional view of the head in the direction parallel to the nozzle arrangement direction. 4 is a plan explanatory view of the nozzle plate of the head, FIG. 5 is a plan explanatory view of each member constituting the flow path member of the head, and FIG. 6 is a plan explanatory view of each member constituting the common liquid chamber member of the head It is. 8 is a cross-sectional view taken along the line A-A 'of FIG. 2, and FIG. 9 is a cross-sectional view taken along the line B-B' of FIG.

The liquid discharge head laminates and joins the nozzle plate 1, the flow path plate 2, and the diaphragm member 3 as a wall surface member. The piezoelectric actuator 11 for displacing the diaphragm member 3, the common liquid chamber member 20, and the cover 29 are provided.
The nozzle plate 1 has a plurality of nozzles 4 for discharging a liquid.
The channel plate 2 forms an individual liquid chamber 6 communicating with the nozzle 4, a fluid resistance portion 7 communicating with the individual liquid chamber 6, and a liquid introduction portion 8 communicating with the fluid resistance portion 7. Further, the flow channel plate 2 is formed by laminating and joining a plurality of plate members 41 to 45 from the nozzle plate 1 side, and these plate members 41 to 45 and the diaphragm member 3 are laminated and joined A member 40 is configured.
The diaphragm member 3 has a filter portion 9 as an opening that communicates with the liquid introduction portion 8 and the common liquid chamber 10 formed by the common liquid chamber member 20.
The vibrating plate member 3 is a wall surface member that forms the wall surface of the individual liquid chamber 6 of the flow channel plate 2. The diaphragm member 3 has a two-layer structure (not limited), and is formed of a first layer forming a thin portion from the side of the flow channel plate 2 and a second layer forming a thick portion. A deformable vibration area 30 is formed in a portion corresponding to the chamber 6.

Here, in the nozzle plate 1, as shown in FIG. 4, the plurality of nozzles 4 are arranged in a staggered manner. As shown in FIG. 5A, in the plate-like member 41 constituting the flow channel plate 2, a through groove portion (meaning of a through hole in the shape of a groove) 6a constituting the individual liquid chamber 6, a fluid resistance portion 51, The through groove portions 51 a and 52 a constituting the circulation flow path 52 are formed.
Similarly, in the plate-like member 42, as shown in FIG. 5 (b), a through groove 6b constituting the individual liquid chamber 6 and a through groove 52b constituting the circulation flow passage 52 are formed.
Similarly, as shown in FIG. 5C, in the plate-like member 43, the through groove 6c constituting the individual liquid chamber 6 and the through groove 53a whose longitudinal direction is the nozzle arrangement direction constituting the circulation channel 53 are formed. It is done. Similarly, in the plate-like member 44, as shown in FIG. 5 (d), the through groove portion 6d constituting the individual liquid chamber 6, the through groove portion 7a constituting the fluid resistance portion 7, and the through hole constituting the liquid introduction portion 8 A groove portion 8 a and a through groove portion 53 b whose longitudinal direction is a nozzle arrangement direction constituting the circulation flow path 53 are formed.
Similarly, in the plate member 45, as shown in FIG. 5 (e), the through groove portion 6e constituting the individual liquid chamber 6 and the through groove portion 8b having the nozzle arrangement direction constituting the liquid introduction portion 8 as the longitudinal direction In the downstream side liquid chamber), a through groove portion 53c is formed, the longitudinal direction of which is the nozzle arrangement direction of the circulation flow path 53. As shown in FIG. 5 (f), the vibrating plate member 3 is formed with a vibration region 30, a filter portion 9, and a through groove portion 53d whose longitudinal direction is a nozzle arrangement direction constituting the circulation flow path 53. .
As described above, by forming the flow path member by laminating and joining a plurality of plate members, a complicated flow path can be formed with a simple configuration.

  With the above configuration, in the flow path member 40 including the flow path plate 2 and the vibrating plate member 3, the fluid resistance portion 51, the circulation flow path 52, and the circulation along the surface direction of the flow path plate 2 communicating with each individual liquid chamber 6. A circulation channel 53 in the thickness direction of the channel member 40 communicating with the channel 52 is formed. The circulation flow path 53 communicates with a circulation common liquid chamber 50 described later.

On the other hand, in the common liquid chamber member 20, a common liquid chamber 10 to which the liquid is supplied from the supply / circulation mechanism 494 and a circulating common liquid chamber 50 are formed.
As shown in FIG. 6A, in the first common liquid chamber member 21 constituting the common liquid chamber member 20, a through hole 25a for a piezoelectric actuator, a through groove portion 10a to be the downstream common liquid chamber 10A, and a circulation A groove portion 50 a having a bottom which becomes the common liquid chamber 50 is formed.
Similarly, as shown in FIG. 6B, the second common liquid chamber member 22 is formed with a piezoelectric actuator through hole 25b and a groove 10b to be the upstream common liquid chamber 10B.
Further, referring also to FIG. 1, the second common liquid chamber member 22 is formed with a through hole 71 a serving as a supply port communicating with one end of the common liquid chamber 10 in the nozzle arrangement direction and the supply port 71.
Similarly, in the first common liquid chamber member 21 and the second common liquid chamber member 22, the other end (the end opposite to the through hole 71 a) of the circulation common liquid chamber 50 in the nozzle arrangement direction and the circulation port 81 are provided. Through holes 81a and 81b communicating with each other are formed.
In addition, in FIG. 6, the groove portion having the bottom is shown to be coated (the same applies to the following drawings).
Thus, the common liquid chamber member 20 is constituted by the first common liquid chamber member 21 and the second common liquid chamber member 22, and the first common liquid chamber member 21 is joined to the diaphragm member 3 side of the flow path member 40. The second common liquid chamber member 22 is stacked and joined to the first common liquid chamber member 21.

Here, the first common liquid chamber member 21 forms a downstream common liquid chamber 10 A which is a part of the common liquid chamber 10 communicating with the liquid introduction unit 8 and a circulation common liquid chamber 50 communicating with the circulation flow path 53. ing. Further, the second common liquid chamber member 22 forms an upstream common liquid chamber 10 B which is the remaining portion of the common liquid chamber 10.
At this time, the downstream common liquid chamber 10A which is a part of the common liquid chamber 10 and the circulation common liquid chamber 50 are arranged in a direction perpendicular to the nozzle arrangement direction, and the circulation common liquid chamber 50 is a common liquid chamber 10. It is placed at the position projected inside.

As a result, the dimensions of the circulation common liquid chamber 50 are not restricted by the necessary dimensions of the flow path including the individual liquid chamber 6 formed by the flow path member 40, the fluid resistance portion 7 and the liquid introduction portion 8.
The circulation common liquid chamber 50 and a part of the common liquid chamber 10 are disposed side by side, and the circulation common liquid chamber 50 is disposed at a position projected into the common liquid chamber 10, so that it is orthogonal to the nozzle arrangement direction. The width of the head in the direction can be suppressed, and the enlargement of the head can be suppressed. The common liquid chamber member 20 forms a common liquid chamber 10 and a circulating common liquid chamber 50 to which the liquid is supplied from the head tank or the liquid cartridge.

On the other hand, on the opposite side of the diaphragm member 3 to the individual liquid chamber 6, a piezoelectric actuator 11 including an electromechanical transducer as a drive means for deforming the vibration area 30 of the diaphragm member 3 is disposed.
As shown in FIG. 3, this piezoelectric actuator 11 has a piezoelectric member 12 joined on a base member 13. The piezoelectric member 12 is grooved by half-cut dicing and the required number of grooves for one piezoelectric member 12 is required. The columnar piezoelectric elements 12A and 12B are formed in a comb shape at predetermined intervals.
Here, the piezoelectric element 12A of the piezoelectric member 12 is used as a piezoelectric element to be driven by giving a drive waveform, and the piezoelectric element 12B is used as a simple support without giving a drive waveform, but all piezoelectric elements 12A and 12B are driven It can also be used as a piezoelectric element.
Then, the piezoelectric element 12A is joined to the convex portion 30a which is an island-shaped thick portion formed in the vibration area 30 of the diaphragm member 3. Further, the piezoelectric element 12 B is joined to the convex portion 30 b which is a thick portion of the diaphragm member 3.
The piezoelectric member 12 is formed by alternately laminating piezoelectric layers and internal electrodes, and it has been confirmed in the present invention that a stable discharge state can be obtained with a piezoelectric member having a film thickness of 3 μm or less. The internal electrodes of the piezoelectric member 12 are drawn out to the end faces to provide external electrodes, and the flexible wiring member 15 is connected to the external electrodes.

In the liquid discharge head configured as described above, for example, the voltage applied to the piezoelectric element 12A is lowered from the reference potential, whereby the piezoelectric element 12A contracts and the vibration area 30 of the diaphragm member 3 descends, and the volume of the individual liquid chamber 6 is reduced. The liquid flows into the individual liquid chamber 6 due to the expansion of the liquid.
Thereafter, the voltage applied to the piezoelectric element 12A is increased to elongate the piezoelectric element 12A in the stacking direction, and the vibration area 30 of the diaphragm member 3 is deformed in the direction toward the nozzle 4 to shrink the volume of the individual liquid chamber 6 Thus, the liquid in the individual liquid chamber 6 is pressurized, and the liquid is discharged from the nozzle 4.
Then, the liquid is drawn from the common liquid chamber 10 by the surface tension and filled with the liquid. Finally, since the meniscus surface is stabilized by the balance between the negative pressure defined by the supply tank and the circulation tank and the head difference and the surface tension of the meniscus, it is possible to shift to the next discharge operation.

The method of driving the head is not limited to the above example (pull-push), and depending on the drive waveform, pull or push can be performed. Further, in the above-described embodiment, the laminated piezoelectric element is described as the pressure generating means for applying pressure fluctuation to the individual liquid chamber 6, but the invention is not limited thereto, and a thin film piezoelectric element can be used. . Furthermore, a heat generating resistor may be disposed in the individual liquid chamber 6, and it is possible to use one that generates pressure fluctuation by generating air bubbles by heat generation of the heat generation resistor or that generates pressure fluctuation using electrostatic force. .
Next, an example of a liquid circulation system using the liquid discharge head according to the present embodiment will be described with reference to FIG.

FIG. 7 is a block diagram showing a liquid circulation system according to the present embodiment.
As shown in FIG. 7, the liquid circulation system includes a main tank, a liquid discharge head, a supply tank, a circulation tank, a compressor, a vacuum pump, a liquid feed pump, a regulator (R), a supply pressure sensor, a circulation pressure sensor, etc. It is configured. The supply-side pressure sensor is connected between the supply tank and the liquid discharge head and on the supply flow path side connected to the supply port 71 (see FIG. 1) of the liquid discharge head. The circulation side pressure sensor is connected between the liquid discharge head and the circulation tank and on the side of the circulation flow path connected to the circulation port 81 (see FIG. 1) of the liquid discharge head.
One of the circulation tanks is connected to the supply tank via the first liquid feed pump, and the other one of the circulation tanks is connected to the main tank via the second liquid feed pump. As a result, the liquid flows from the supply tank into the liquid discharge head through the supply port 71, is discharged from the circulation port and is discharged to the circulation tank, and the liquid is sent from the circulation tank to the supply tank by the first liquid feed pump. Liquid circulates by

Further, a compressor is connected to the supply tank, and control is performed such that a predetermined positive pressure is detected by the supply-side pressure sensor. On the other hand, a vacuum pump is connected to the circulation tank, and control is performed so that a predetermined negative pressure is detected by the circulation side pressure sensor. This allows the negative pressure of the meniscus to be kept constant while circulating the liquid through the liquid discharge head.
In addition, when droplets are discharged from the nozzle of the liquid discharge head, the amount of liquid in the supply tank and the circulation tank decreases, so the liquid from the main tank to the circulation tank is appropriately used from the main tank using the second liquid transfer pump. It is desirable to replenish The timing of liquid replenishment from the main tank to the circulation tank depends on the detection result of the liquid level sensor etc. provided in the circulation tank, such as performing liquid replenishment when the ink level in the circulation tank falls below a predetermined level. Can be controlled.

  Next, circulation of the liquid in the liquid discharge head will be described. As shown in FIG. 1, at the end of the common liquid chamber member 20, a supply port 71 communicating with the common liquid chamber and a circulation port 81 communicating with the circulating common liquid chamber 50 are formed. The supply port 71 and the circulation port 81 are each connected via a tube to a supply tank / circulation tank (see FIG. 7) for storing liquid. Then, the liquid stored in the supply tank is supplied to the individual liquid chamber 6 through the supply port 71, the common liquid chamber 10, the liquid introduction unit 8, and the fluid resistance unit 7.

Furthermore, while the liquid in the individual liquid chamber 6 is discharged from the nozzle 4 by the drive of the piezoelectric element 12, a part or all of the liquid remaining in the individual liquid chamber 6 without being discharged is the fluid resistance portion 51, circulation. The fluid is circulated to the circulation tank through the flow paths 52, 53, the circulation common liquid chamber 50, and the circulation port 81.
The circulation of the liquid can be performed not only at the time of operation of the liquid discharge head but also at the time of operation rest. By circulating at the time of operation rest, the liquid in the individual liquid chamber can be constantly refreshed, and aggregation and sedimentation of the components contained in the liquid can be suppressed, which is preferable.

Next, an example of a device for discharging a liquid according to the present invention will be described with reference to FIGS. 10 and 11. FIG. FIG. 10 is an explanatory plan view of an essential part of the apparatus, and FIG. 11 is an explanatory side view of an essential part of the apparatus.
This apparatus is a serial type apparatus, and the carriage 403 reciprocally moves in the main scanning direction by the main scanning movement mechanism 493. The main scanning movement mechanism 493 includes a guide member 401, a main scanning motor 405, a timing belt 408, and the like. The guide member 401 is bridged by the left and right side plates 491A and 491B and holds the carriage 403 movably. Then, the carriage 403 is reciprocated in the main scanning direction via the timing belt 408 bridged between the drive pulley 406 and the driven pulley 407 by the main scanning motor 405.
On the carriage 403 is mounted a liquid discharge unit 440 on which the liquid discharge head 404 according to the present invention is mounted. The liquid ejection head 404 of the liquid ejection unit 440 ejects, for example, liquid of each color of yellow (Y), cyan (C), magenta (M), and black (K). Further, the liquid discharge head 404 has a nozzle row consisting of a plurality of nozzles arranged in the sub-scanning direction orthogonal to the main scanning direction, and is mounted with the discharge direction downward.
The liquid is supplied and circulated in the liquid ejection head 404 by the supply / circulation mechanism 494 for supplying the liquid stored in the liquid ejection head 404 to the liquid ejection head 404. In the present embodiment, the supply / circulation mechanism 494 includes a supply tank, a circulation tank, a compressor, a vacuum pump, a liquid feed pump, a regulator (R), and the like. Further, the supply-side pressure sensor is connected between the supply tank and the liquid discharge head and on the supply flow path side connected to the supply pipe port 71 of the liquid discharge head. The circulation side pressure sensor is connected between the liquid discharge head and the circulation tank and on the side of the circulation flow path connected to the circulation port 81 of the liquid discharge head.

The apparatus includes a transport mechanism 495 for transporting the sheet 410. The transport mechanism 495 includes a transport belt 412 which is transport means, and a sub scanning motor 416 for driving the transport belt 412.
The conveyance belt 412 adsorbs the sheet 410 and conveys the sheet 410 at a position facing the liquid discharge head 404. The conveyance belt 412 is an endless belt and is stretched between the conveyance roller 413 and the tension roller 414. The adsorption can be performed by electrostatic adsorption or air suction.
The conveyance belt 412 rotates in the sub-scanning direction as the conveyance roller 413 is rotationally driven by the sub-scanning motor 416 via the timing belt 417 and the timing pulley 418.
Further, on one side of the carriage 403 in the main scanning direction, a maintenance recovery mechanism 420 for maintaining and recovering the liquid discharge head 404 is disposed on the side of the transport belt 412.
The maintenance and recovery mechanism 420 includes, for example, a cap member 421 for capping the nozzle surface (surface on which the nozzle is formed) of the liquid discharge head 404, a wiper member 422 for wiping the nozzle surface, and the like.
The main scanning movement mechanism 493, the supply and circulation mechanism 494, the maintenance and recovery mechanism 420, and the transport mechanism 495 are attached to a housing including the side plates 491A and 491B and the back plate 491C.

In this apparatus configured as described above, the sheet 410 is fed and adsorbed onto the conveyance belt 412, and the sheet 410 is conveyed in the sub-scanning direction by the circumferential movement of the conveyance belt 412.
Therefore, the liquid ejection head 404 is driven according to the image signal while moving the carriage 403 in the main scanning direction, thereby ejecting the liquid onto the stopped sheet 410 to form an image.
As described above, in this apparatus, since the liquid discharge head according to the present invention is provided, a high quality image can be stably formed.
Next, another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 12 is an explanatory plan view of the main part of the unit.
Among the members constituting the device for discharging the liquid, the liquid discharge unit includes a housing portion constituted by the side plates 491A and 491B and the back plate 491C, the main scanning movement mechanism 493, the carriage 403, and the liquid It comprises the discharge head 404.
It is also possible to construct a liquid discharge unit in which at least one of the aforementioned maintenance and recovery mechanism 420 and the supply / circulation mechanism 494 is further attached to, for example, the side plate 491B of this liquid discharge unit.

In the present invention, the “liquid discharge head” is a functional component that discharges and discharges the liquid from the nozzle.
The liquid to be discharged is not particularly limited as long as it has a viscosity and surface tension that can be discharged from the head, and the viscosity is 30 mPa · s or less at normal temperature and normal pressure, or by heating and cooling. Is preferred. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, polymerizable compounds, functionalizing materials such as resins and surfactants, and biocompatible materials such as DNA, amino acids, proteins and calcium Solutions, suspensions, emulsions, etc. containing edible materials such as natural pigments, etc. These are, for example, ink jet inks, surface treatment liquids, components of electronic devices and light emitting devices, and formation of electronic circuit resist patterns It can be used in applications such as liquids for liquids, material liquids for three-dimensional modeling and the like.

Use a piezoelectric actuator (laminated piezoelectric element and thin film piezoelectric element), a thermal actuator using an electrothermal transducer such as a heating resistor, an electrostatic actuator consisting of a diaphragm and a counter electrode, etc. as an energy source to discharge liquid It includes what you do.
The “liquid discharge unit” is a liquid discharge head in which functional parts and mechanisms are integrated, and is a collection of parts related to the discharge of liquid. For example, the “liquid discharge unit” includes a combination of a supply / circulation mechanism, a carriage, a maintenance recovery mechanism, and at least one of the configurations of a main scanning movement mechanism with a liquid discharge head.
Here, integration means, for example, one in which the liquid discharge head and the functional component or mechanism are fixed to each other by fastening, bonding, engagement or the like, or one in which one is held movably with respect to the other. Including. In addition, the liquid discharge head, the functional components, and the mechanism may be configured to be removable from each other.
For example, there is a liquid discharge unit in which a liquid discharge head and a supply / circulation mechanism are integrated. In addition, there is one in which the liquid discharge head and the supply / circulation mechanism are integrated by being connected to each other by a tube or the like. Here, it is also possible to add a unit including a filter between the supply / circulation mechanism of these liquid discharge units and the liquid discharge head.
Further, as a liquid discharge unit, there is one in which a liquid discharge head and a carriage are integrated.

Further, as a liquid discharge unit, there is one in which the liquid discharge head is movably held by a guide member constituting a part of the scanning movement mechanism, and the liquid discharge head and the scanning movement mechanism are integrated.
Further, as a liquid discharge unit, there is one in which a cap member which is a part of a maintenance recovery mechanism is fixed to a carriage attached with a liquid discharge head, and the liquid discharge head, the carriage and the maintenance recovery mechanism are integrated. .
Further, as a liquid discharge unit, there is a type in which a tube is connected to a liquid discharge head to which a supply / circulation mechanism or a flow path part is attached, and the liquid discharge head and the supply mechanism are integrated. The liquid of the liquid storage source is supplied to the liquid discharge head through the tube.
The main scanning movement mechanism also includes a single guide member. The supply mechanism also includes a single tube and a single loading unit.

In the present invention, the “device for discharging a liquid” is a device including a liquid discharge head or a liquid discharge unit, and driving the liquid discharge head to discharge the liquid. The device for discharging the liquid includes not only a device capable of discharging the liquid to those to which the liquid can adhere, but also a device for discharging the liquid into the air or into the liquid.
This "device for discharging liquid" can also include means related to feeding, transporting, and discharging of those to which the liquid can be attached, as well as a pre-processing device, a post-processing device, and the like.
For example, as a “device for discharging a liquid”, an image forming device which is a device for discharging an ink to form an image on a sheet, and forming a powder in layers to form a three-dimensional object (three-dimensional object) There is a three-dimensional modeling apparatus (three-dimensional modeling apparatus) which discharges a modeling liquid to the powder layer.

Further, the “device for discharging liquid” is not limited to a device in which a significant image such as characters and figures is visualized by the discharged liquid. For example, those which form patterns having no meaning per se and those which form three-dimensional images are included.
The above-mentioned "thing to which liquid can be attached" means one to which liquid can be attached at least temporarily, which adheres and adheres, and adheres and penetrates. Specific examples include recording media such as paper, recording paper, recording paper, film, cloth, electronic substrates, electronic components such as piezoelectric elements, and media such as powder layers (powder layers), organ models, and inspection cells. Yes, and unless otherwise specified, all things to which the liquid adheres are included.

The material of the above-mentioned "thing to which liquid can adhere" may be any liquid such as paper, yarn, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, etc. as long as it temporarily adheres thereto.
The “liquid” is not particularly limited as long as it has a viscosity and surface tension that can be discharged from the head, but the viscosity is 30 mPa · s or less at normal temperature and normal pressure, or by heating and cooling. Is preferred. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, polymerizable compounds, functionalizing materials such as resins and surfactants, and biocompatible materials such as DNA, amino acids, proteins and calcium Solutions, suspensions, emulsions, etc. containing edible materials such as natural pigments, etc. These are, for example, ink jet inks, surface treatment liquids, components of electronic devices and light emitting devices, and formation of electronic circuit resist patterns It can be used in applications such as liquids for liquids, material liquids for three-dimensional modeling and the like.

Further, as the “device for discharging the liquid”, there is a device in which the liquid discharge head and the device to which the liquid can be attached relatively move, but it is not limited to this. Specific examples include a serial type device that moves the liquid discharge head, a line type device that does not move the liquid discharge head, and the like.
In addition, as “a device for discharging a liquid”, a treatment liquid application device for discharging a treatment liquid onto a sheet of paper to apply the treatment liquid to the surface of the sheet for the purpose of reforming the surface of the sheet, etc. There is an injection granulator etc. which granulates the fine particles of the raw material by injecting the composition liquid which is dispersed in the solution through the nozzle.

(Cured product, manufacturing method of cured product)
The cured product of the present invention is a cured product of the curable liquid composition of the present invention, and the curable liquid composition of the present invention is discharged from a liquid composition discharge device provided with a discharge head, and the cured liquid is discharged. The liquid composition can be produced by light irradiation and curing.
In addition, the curable liquid composition of the present invention is provided with the discharge head described above, and the discharge head includes a plurality of nozzles for discharging the liquid, an individual liquid chamber communicating with the nozzles, and the individual liquid chamber. It comprises: a common liquid chamber for supplying liquid, a circulation flow path leading to the individual liquid chamber, a circulation common liquid chamber leading to the circulation flow path, and pressure generating means for applying pressure to the liquid in the individual liquid chamber. The liquid composition discharge device can be used to eject the curable liquid composition that has been ejected, and to cure the cured liquid composition.

  In addition, as a usage method of the composition of this invention, it is not restrict | limited to the liquid discharge method using the apparatus which discharges liquid, It is possible to use widely. Besides the liquid discharge method, for example, a blade coating method, a gravure coating method, a bar coating method, a roll coating method, a dip coating method, a curtain coating method, a slide coating method, a die coating method, a spray coating method and the like can be mentioned.

  Further, in the terms of the present application, image formation, recording, printing, printing, printing, modeling, and the like are all synonymous.

(Coated substrate)
The substrate to be coated (also referred to as a substrate to be printed) is not particularly limited, but from the viewpoint of curing and drying by light irradiation, it penetrates to the deep part of the substrate and does not reach light irradiation. It is particularly preferable to a substrate having low permeability such as paper, plastic, metal, glass having a coated layer, rather than a highly transparent substrate.

The following (1)-(10) can be mentioned as embodiment of this invention.
(1) A curable liquid composition containing a monomer having an SI value of less than 3.0 and a photopolymerization initiator having a weight average molecular weight of 500 or more and having negative skin sensitization.
(2) The curable type as described in the above (1), wherein the photopolymerization initiator is a photopolymerization initiator having a chemical structure containing a phenyl glyoxylate skeleton and / or a photopolymerization initiator having a chemical structure containing a benzophenone skeleton. Liquid composition.
(3) The curable liquid composition according to the above (1), wherein the photopolymerization initiator is a photopolymerization initiator having a chemical structure containing a nitrogen atom.
(4) The curable liquid composition according to any one of the above (1) to (3), which contains a hydroxyl group-containing monomer as the monomer.
(5) A composition storage container containing the curable liquid composition according to any one of the above (1) to (4).
(6) A liquid composition discharge device comprising the composition storage container according to (5).
(7) A liquid composition discharge device comprising a discharge head for discharging the curable liquid composition according to any one of (1) to (4) above,
The discharge head is
A plurality of nozzles for discharging liquid,
A separate fluid chamber leading to the nozzle;
A common liquid chamber for supplying liquid to the individual liquid chamber;
A circulation channel leading to the individual liquid chamber;
A circulation common liquid chamber leading to the circulation channel;
And pressure generating means for applying pressure to the liquid in the individual liquid chamber.
Liquid composition discharge device.
(8) A cured product of the curable liquid composition according to any one of the above (1) to (4).
(9) The curable liquid composition according to any one of the above (1) to (4) is ejected from a liquid composition ejection device provided with an ejection head, and the ejected curable liquid composition is irradiated with light. A method of producing a cured product which is cured by irradiation.
(10) The curable liquid composition according to any one of the above (1) to (4),
Equipped with a discharge head,
The discharge head is
A plurality of nozzles for discharging liquid,
A separate fluid chamber leading to the nozzle;
A common liquid chamber for supplying liquid to the individual liquid chamber;
A circulation channel leading to the individual liquid chamber;
A circulation common liquid chamber leading to the circulation channel;
And pressure generating means for applying pressure to the liquid in the individual liquid chamber.
Discharge using a liquid composition discharge device,
The manufacturing method of the hardened | cured material made to be light-irradiated and hardened | cured to the discharged | emitted hardening type liquid composition.

  EXAMPLES Hereinafter, the present invention will be more specifically described by way of examples, but the present invention is not limited by these examples.

<Evaluation method of SI value>
Said SI value was measured as follows according to the skin sensitization test by LLNA method (Local Lymph Node Assay).
[Test material]
<< Positive control substance >>
As a positive control substance, α-hexyl cinnamaldehyde (HCA; manufactured by Wako Pure Chemical Industries, Ltd.) was used.
<< medium >>
As a medium, a mixture of acetone (manufactured by Wako Pure Chemical Industries, Ltd.) and olive oil (manufactured by Fudimi Pharmaceutical Co., Ltd.) at a volume ratio of 4: 1 was used.
Used animal
For each of the test substance, the positive control and the vehicle control, the females of the mice were subjected to 8 days of conditioning including 6 days of quarantine. During quarantine and acclimation, no abnormality was observed in all animals.
Using body weight measured 2 days before the onset of feeling, the animals were divided into 2 groups (4 animals / group) so that the individual's body weight would be within ± 20% of the total average body weight by weight layering random sampling method . The age of the animals at the onset of feeling was 8-9 weeks. Animals removed by grouping were excluded from the study.
The animals used were identified by oil-based ink application to the tail throughout the test period, and cages were identified by labeling.
<< breeding environment >>
The animals used are temperature 21-25 ° C, relative humidity 40-70%, ventilation frequency 10-15 times / hour, light and dark cycle 12 hours sense (7 o'clock to 19 o'clock) throughout the whole breeding period including during quarantine and acclimation period The animals were bred in the breeding room of the barrier system set to “off”.
The rearing cage used a polycarbonate cage. The animals used were reared at 4 per cage.
As a feed, a solid feed MF for laboratory animals (manufactured by Oriental Yeast Co., Ltd.) was used and allowed to be freely consumed by used animals. As for the drinking water, using water supply bottles, tap animals were allowed to freely consume tap water to which sodium hypochlorite (Peurax, manufactured by Aoyalux Co., Ltd.) was added so that the chlorine concentration was approximately 5 ppm. The floor was made of sunflake (fir wood, electric planer shavings, manufactured by Nippon Charles River Co., Ltd.). As the feed and the breeding equipment, those which had been autoclaved (121 ° C., 30 minutes) were used respectively.
The cages and bedding were changed at the time of grouping and the day of ear lymph node intake (at the time of discharge from the breeding room), and the water bottles and racks were changed at the time of grouping.

[Test method]
Group configuration
Table 1 shows the group configuration used in the SI value measurement test.

[Preparation]
Test substance
Table 2 shows the weighing conditions of the test substance. The test substance was weighed into a volumetric flask and made up to 1 mL while adding the medium. The preparation solution was placed in a light-tight airtight container (made of glass).

<< Positive control substance >>
Approximately 0.25 g of HCA was accurately weighed, and 25.0 w / v% solution was prepared as 1 mL while adding the medium. The preparation was placed in a lightproof airtight container (made of glass).
<< BrdU >>
200 mg of 5-bromo-2'-deoxyuridine (BrdU, manufactured by Nacalai Tesque, Inc.) was accurately weighed in a measuring flask, physiological saline (manufactured by Otsuka Pharmaceutical Co., Ltd.) was added, and the mixture was sonicated and dissolved. Thereafter, the volume was adjusted to 20 mL to prepare a 10 mg / mL solution (BrdU preparation solution). The preparation was filter-sterilized using a sterile filter and placed in a sterile container.
Preparation time and storage period
The positive control preparation was prepared the day before the onset of the sensation and was stored in a cold place except when used. Vehicle and test substance preparation solutions were prepared each day. BrdU solution was prepared two days before the administration and was stored in the cold until the day of administration.

[Feeling and BrdU administration]
"Feeling"
Preparation solutions of each test substance and positive control substance and vehicle were applied in 25 μl to both auricles of the animal. A micro pipettor was used for application. This operation was performed once a day for 3 consecutive days.
Administration of BrdU
The BrdU preparation was intraperitoneally administered 0.5 mL per animal once approximately 48 hours after the final feeling.

[Observation and inspection]
<< General state >>
All animals used in the test were observed at least once a day from the day when the feeling was felt to the day when the auricular lymph node was collected (the day when they were taken out of the breeding room). In addition, the counting method of the observation date was Day 1 as the perceived start date.
Weight measurement
Body weight was measured on the day when the feeling started and the day of ear lymph node collection (the day of removal from the breeding room). In addition, the mean value and standard error of body weight for each group were calculated.
Collection and weighing of ear lymph nodes
The animals were euthanized approximately 24 hours after BrdU administration and the auricular lymph nodes were harvested. The surrounding tissue was removed and both auricular lymph nodes were weighed in bulk. In addition, the mean and standard error of ear ring node weights for each group were calculated. After weighing, each animal was cryopreserved in a biomedical freezer set at -20 ° C.
<< Measurement of BrdU uptake amount >>
The ear lymph nodes were returned to room temperature and then ground and suspended while adding saline. The suspension was filtered, and then 3 wells per individual were dispensed into 96-well microplates, and BrdU incorporation was measured by ELISA. The reagents used were commercially available kits (Cell Proliferation ELISA, BrdU colorimetric, Cat. No. 1647229, manufactured by Roche Diagnostics) and each obtained from a multiplate reader (FLUOstar OPTIMA, manufactured by BMG LABTECH) About the light absorbency (OD370nm-OD492nm, BrdU incorporation amount) of an individual, the average value of 3 wells was made into the BrdU measured value of each individual.

[Result evaluation]
<< Calculation of Stimulation Index (SI) >>
As shown in the following formula, the BrdU measurement value of each individual was divided by the average value of the BrdU measurement values of the vehicle control group to calculate the SI value of each individual. The SI value of each test group was taken as the average value of SI of each individual. The SI value is displayed to the first decimal place after rounding off the second decimal place.

(Examples 1 to 9, Comparative Examples 1 to 4)
The following materials (A) to (C) were mixed at blending ratios (numerical values are parts by mass) shown in each column of Examples and Comparative Examples of Table 3 to obtain an ink.
(A) Monomer whose SI value is less than 3.0. Naturally, those which are considered to be skin sensitization negative by other means and the like are included in this.
(B) Photopolymerization initiator having a molecular weight of less than 500 (C) Photopolymerization initiator having a molecular weight of 500 or more The details of A1 to A8, B1 to B3 and C1 to C6 described in Table 3 are as follows. The numerical value in () at the end is SI value in the above-mentioned LLNA test, and "none" was evaluated as "skin sensitization negative" or "no skin sensitization" in SDS (safety data sheet) It is a thing. "No GHS pictograms that indicate hazards to SDS" means "no skin sensitization".
The inks of Examples 1 to 9 and Comparative Examples 1 to 3 use only materials having negative skin sensitization and have negative skin sensitization, but the ink of Comparative 4 has an SI value Is 10% by weight in the ink, the skin sensitization is positive.

A1: Diethylene glycol dimethacrylate "2G" manufactured by Shin-Nakamura Chemical Co., Ltd. (1.1)
A2: caprolactone modified with dipentaerythritol hexaacrylate "DPCA 60" manufactured by Nippon Kayaku Co., Ltd. (none: evaluation with SDS)
A3: Ethylene oxide modified bisphenol A diacrylate "BPE-10" (1.2) manufactured by Daiichi Kogyo Seiyaku Co., Ltd.
A4: Polypropylene glycol diacrylate "M-270" (1.5) manufactured by Toagosei Chemical Co., Ltd.
A5: Isostearyl Acrylate "S-1800A" (1.4) manufactured by Shin-Nakamura Chemical Co., Ltd.
A6: Tricyclodecane dimethanol dimethacrylate "DCP" (1.3) made by Shin-Nakamura Chemical Co., Ltd.
A7: Glycerol dimethacrylate "701" (1.2) manufactured by Shin-Nakamura Chemical Co., Ltd.
A8: Glycerol monomethacrylate "GLM" manufactured by NOF Corporation (1.1)

B 1: 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one IGM “Omnirad 2959” (none: evaluation with SDS) weight average molecular weight 224
B2: 1-hydroxy-cyclohexyl-phenyl-ketone IGM "Omnirad 184" (none: evaluation with SDS) weight average molecular weight 204
B3: 2- (dimethylamino) -1- (4-morpholinophenyl) -2-benzyl-1-butanone “Omnirad 369” (10) manufactured by IGM, weight average molecular weight 366

C1: Polybutylene glycol-bis-phenyl glyoxylate "Ominipol 2712" manufactured by IGM (without GHS pictogram showing hazard to SDS) weight average molecular weight 514
C2: diester of polytetramethylene glycol 250 and carboxymethoxybenzophenone IGM "Ominipol BP" (without GHS pictogram showing hazard to SDS) weight average molecular weight 730
C3: Diester of polyalkylene glycol and carboxybenzophenone IGM "Ominipol 2702" (without GHS pictogram showing hazard to SDS) weight average molecular weight 620
C4: polyethylene glycol-bis-dimethylaminobenzoate IGM "Ominipol ASA" (without GHS pictogram showing hazard to SDS) weight average molecular weight 510
C5: Polytetramethylene glycol 250 and a diester of carboxymethoxythioxanthone “Ominipol TX” manufactured by IGM (without GHS pictogram showing hazard to SDS) weight average molecular weight 790
C6: polyethylene glycol 200-di- (β-4 [4- (2-dimethylamino-2-benzyl) butanoylphenyl] piperazine) propionate “Ominipol 910” manufactured by IGM (a GHS picture showing hazard to SDS is not displayed ) Weight average molecular weight 1039

<Curable and odor of cured coating>
The curability of each ink and the odor of the cured coating were evaluated. The evaluation results of each ink are shown in Table 3.
A commercially available polyethylene terephthalate film (Cosmo Shine manufactured by Toyobo Co., Ltd. / thickness 188 microns) is used as a general-purpose film material for the substrate, and the film is jet-jetted to the film to obtain a metal halide lamp (Light Hammer 6 manufactured by Heraeus). The film was irradiated with light with the illuminance and the integrated light amount described in the above, and the coating film was touched with a finger to determine that it had reached a non-tacky state as “cured”. An uncured or semi-cured product was judged as "uncured". In addition, after 1 hour of light irradiation, the odor of the coating film was evaluated functionally, and those having strong odor were judged as "stimulative odor" and those having weak odor were judged as "low odor".
As the curing test, a curing test 1 with a small amount of irradiation light and a curing test 2 with a large dose were conducted.
Even a small amount of light in the curing test 1 was uncured, but a large amount of light in the curing test 2 cured. Generally, the curability also depends on the amount of radicals generated at the time of light irradiation. Therefore, when it is desired to cure with a smaller amount of light, a large amount of a photopolymerization initiator which is a radical generation source may be blended. However, when the content of the photopolymerization initiator is increased, the viscosity of the ink is increased and the cost is increased.
In addition, evaluation of the odor of a coating film was performed about the coating film obtained by the hardening test 2 shown in Table 3.

  First, for handling the ink, the ink is sealed so that air bubbles do not enter the aluminum pouch bag having the shape shown in FIG. 13, and the above pouch bag in which the ink is sealed in the plastic cartridge as shown in FIG. The ink flow path is set up from the cartridge to the Ricoh MH5420 head (discharge head having no flow path circulating in the individual liquid chamber) from the cartridge in the housing which can accommodate the cartridge, and the ink discharge is thereby performed. A 3 cm × 10 cm solid image was produced. The amount of ink droplets deposited was adjusted to a coating thickness of about 20 microns.

  It is desirable that the physical properties of the ink conform to the required specifications of the ink jet discharge head to be used. A variety of ejection heads are commercially available from many manufacturers, but among them, there are those having a large ejection power that can cope with high viscosity ink, and those having a wide range of temperature control functions. Considering such a situation, the viscosity of the ink is preferably 2 to 150 mPa · s at 25 ° C., and more preferably 5 to 18 mPa · s in consideration of ejection at 25 ° C. However, as described above, it is also possible to use the temperature control function of the discharge head, and if the viscosity is too high at 25 ° C., heating the head if necessary to reduce the viscosity of the ink Assuming that the temperature is 60 ° C., the viscosity at 60 ° C. is preferably 2 to 20 mPa · s, more preferably 5 to 18 mPa · s. However, from the viewpoint of energy saving, shortening of the operation preparation time, etc., it is more desirable to be able to discharge at a lower temperature. In the comparative example and the example, the ink viscosity was 8 to 15 mPa · s at a discharge temperature of 30 to 60 ° C.

From Example 1 and Comparative Example 1, it was found that curability and low bromide can be simultaneously achieved by using an initiator having a molecular weight of 500 or more. As in Comparative Example 2, low bromide may be achieved even with an initiator having a molecular weight of less than 500, but coexistence with good curability is difficult, and as in Comparative Example 3, it is started to improve curability. It was found that increasing the amount of the agent causes problems in solubility.
As in Example 2, it was found that by using an initiator having a molecular weight of 500 or more, curability and low bromide can be simultaneously achieved, and the curability can be further improved by adjusting the amount of the initiator.
As in Example 3, it was found that curability and low bromide can be simultaneously achieved by using plural kinds of initiators having a molecular weight of 500 or more.
As in Examples 4 to 6, it is found that curability and low bromide can be simultaneously achieved when using an initiator having a molecular weight of 500 or more and using monomers having a plurality of types of SI values less than 3.0. The
As in Example 6, it was found that even when an initiator having a molecular weight of 500 or more is used in combination with an initiator having a molecular weight of less than 500, curability and low bromide can be simultaneously achieved.
As in Examples 7 and 8, when an initiator having a molecular weight of 500 or more is used, curability and low bromide can be simultaneously achieved both when the colorant is contained and when the colorant is not contained. I understood.
It was found that when a colorant is contained as in Examples 3 and 8, good curability can be exhibited by using an initiator having a molecular weight of 500 or more containing a nitrogen atom.
In Example 9, since a large amount of hydroxyl group-containing monomers is used, even when a general-purpose slide glass with a clean surface is used as a substrate, a commercially available cellophane tape may be attached to the coating film and peeled vigorously, The coating was in close contact with the glass slide of the substrate, and it was found that in addition to the curability and low bromide, adhesion to the glass substrate can be achieved simultaneously.
Among the examples in which the coloring material is not contained, in Example 1, the cured coating film is colored pale yellow, so it seems to be suitable for applications where pale yellow is required and applications where the color tone is not affected. In Examples 2, 4, 5, 6, 7 and 9, no noticeable coloration was observed in the coating, so it seems to be suitable for applications where it is desirable not to inhibit the color tone of the substrate or the substrate.
In addition, since the initiator has absorption between 365 nm and 395 nm, it also absorbs in this region as an ink. It is possible to measure a spectrum by the visible light ultraviolet light spectrophotometer generally used.

<Discharge reliability>
In the case of using a liquid discharge apparatus having a discharge head having no flow path circulating in the individual liquid chamber using the ink of Example 2, and a flow-through type liquid discharge apparatus circulating in the individual liquid chamber The ejection reliability was evaluated.
A liquid discharge device having a discharge head which does not have a flow path circulating in the individual liquid chamber after being filled with ink and left at 40 ° C. and 95% RH for 12 hours, and a flow through type liquid discharge which circulates in the individual liquid chamber The temperature is adjusted using each of the devices, and the ink having a viscosity of 6 to 11 mPa · s is ejected as droplets of 3 to 15 pl, and a commercially available polyethylene terephthalate film (Cosmo Shine manufactured by Toyobo Co., Ltd./thickness 188 μm) The nozzle check pattern was printed on the top to determine the normal discharge rate from the number of normal discharge nozzles in the total number of nozzles 384 of the first discharge droplets.
When a liquid discharge device having a discharge head having no flow path circulating in the individual liquid chamber was used, the normal discharge rate was 30%, but a flow-through type liquid discharge device that circulates in the individual liquid chamber The normal discharge rate when using was 95%.

In addition, using the ink of Example 2, using a liquid device having a discharge head having a flow path circulating in the individual liquid chamber, the temperature is adjusted and the ink having a viscosity of 6 to 11 mPa · s is completely processed. The droplet of 3 to 15 pl is ejected using a head with 2656 nozzles and a head with 1920 total nozzles, and normal ejection from the number of normal ejection nozzles in the total number of nozzles as in the above evaluation of ejection reliability. The rate was determined.
When the total number of nozzles was 2,656, and when the total number of nozzles was 1,920, the normal ejection rate was 90%.

(With reference to FIGS. 1 to 6 and FIGS. 8 to 9)
DESCRIPTION OF SYMBOLS 1 nozzle plate 2 flow path plate 3 diaphragm member 4 nozzle 6 individual liquid chamber 6a, 6b, 6c, 6d, 6e through groove portion constituting individual liquid chamber 7 fluid resistance portion 7a through groove portion constituting fluid resistance portion 8 liquid introduction Parts 8a, 8b Through groove parts constituting the liquid introduction part 9 filter part 10 common liquid chamber 10A downstream common liquid chamber 10a through groove part 10B upstream common liquid chamber 10b groove part 11 piezoelectric actuator 12 piezoelectric member 12A, 12B piezoelectric element 13 base member DESCRIPTION OF SYMBOLS 15 flexible wiring member 20 common liquid chamber member 21 1st common liquid chamber member 22 2nd common liquid chamber member 25a, 25b piezoelectric actuator through hole 29 cover 30 vibration area 30a, 30b convex part 40 flow path member 41-45 plate shape Member 50 circulation common liquid chamber 50a groove portion 51 fluid resistance portion 51a through groove portion 52 constituting fluid resistance portion; 3 circulation passage 52a, through the groove 53a constituting the 52b circulation passage, 53b, 53c, constitutes a 53d circulation passage through grooves 71 supply port 71a through hole 81 circulation ports 81a, 81b through hole

(About FIG. 10-FIG. 12)
401 guide member 403 carriage 404 liquid discharge head 405 main scanning motor 406 drive pulley 407 driven pulley 408 timing belt 410 sheet 412 conveyance belt 413 conveyance roller 414 tension roller 416 sub scanning motor 417 timing belt 418 timing pulley 420 maintenance recovery mechanism 421 cap member 422 Wiper member 440 Liquid discharge unit 491A, 491B Side plate 491C Back plate 493 Main scanning movement mechanism 494 Supply / circulation mechanism 495 Conveying mechanism

(About FIG. 13-FIG. 15)
21 printing substrate supply roll 22 printing substrate 23 printing unit 23a printing unit 23b of each color printing unit 23c of each color printing unit 23d printing unit of each color 24a ultraviolet light source 24b ultraviolet light source 24c ultraviolet light source 24d ultraviolet light source 25 processing unit Reference Signs List 26 print taking-up roll 200 ink cartridge 241 ink bag 242 ink inlet 243 ink outlet 244 cartridge case

Japanese Patent Publication No. 2004-526820

Claims (10)

  A curable liquid composition containing a monomer having an SI value of less than 3.0 and a photopolymerization initiator having a weight average molecular weight of 500 or more and having negative skin sensitization.   The curable liquid composition according to claim 1, wherein the photopolymerization initiator is a photopolymerization initiator having a chemical structure containing a phenylglyoxylate skeleton and / or a photopolymerization initiator having a chemical structure containing a benzophenone skeleton.   The curable liquid composition according to claim 1, wherein the photopolymerization initiator is a photopolymerization initiator having a chemical structure containing a nitrogen atom.   The curable liquid composition according to any one of claims 1 to 3, which contains a hydroxyl group-containing monomer as the monomer.   The composition accommodating container which accommodated the curable liquid composition as described in any one of Claims 1-4.   The liquid composition discharge apparatus provided with the composition accommodation container of Claim 5. It is a liquid composition discharge apparatus provided with the discharge head which discharges the hardening type liquid composition as described in any one of Claims 1-4,
The discharge head is
A plurality of nozzles for discharging liquid,
A separate fluid chamber leading to the nozzle;
A common liquid chamber for supplying liquid to the individual liquid chamber;
A circulation channel leading to the individual liquid chamber;
A circulation common liquid chamber leading to the circulation channel;
And pressure generating means for applying pressure to the liquid in the individual liquid chamber.
Liquid composition discharge device.   A cured product of the curable liquid composition according to any one of claims 1 to 4.   A curable liquid composition according to any one of claims 1 to 4 is discharged from a liquid composition discharge device provided with a discharge head, and cured by irradiating the cured liquid composition discharged with light. Method of manufacturing objects. The curable liquid composition according to any one of claims 1 to 4,
Equipped with a discharge head,
The discharge head is
A plurality of nozzles for discharging liquid,
A separate fluid chamber leading to the nozzle;
A common liquid chamber for supplying liquid to the individual liquid chamber;
A circulation channel leading to the individual liquid chamber;
A circulation common liquid chamber leading to the circulation channel;
And pressure generating means for applying pressure to the liquid in the individual liquid chamber.
Discharge using a liquid composition discharge device,
The manufacturing method of the hardened | cured material which is made to be light-irradiated and hardened | cured to the discharge | released hardening type liquid composition.