JPH0444577B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a liquid jet recording head, and more particularly, to a liquid jet recording head that generates droplets of a recording liquid such as ink and attaches them to a recording material such as paper to perform recording. The present invention relates to a recording head for generating droplets of recording liquid used in a recording method. [Prior Art] The liquid jet recording method generates small droplets of recording liquid such as ink and attaches them to a recording material such as paper to perform recording, and the noise generated during recording is negligible. It has attracted attention as a recording method that is extremely small and capable of high-speed recording, and can also record on plain paper without the need for special processing such as fixing.Recently, various types of recording methods have been actively researched. There is. The recording head section of a recording device used in a liquid jet recording method generally has an orifice (liquid discharge port) for discharging recording liquid, and communicates with the orifice, so that the energy for discharging the recording liquid can be used for recording. The recording medium is configured to include a liquid passage having a portion that acts on the recording liquid, and a liquid chamber for storing the recording liquid to be supplied to the liquid passage. During recording, the energy for ejecting the recording liquid is generated by a heating element disposed at a predetermined position in a part (energy application part) that applies ejection energy to the recording liquid, which forms part of the liquid path. In many cases, ejection energy is generated by various types of ejection energy generating elements such as piezoelectric elements. A method for manufacturing a liquid jet recording head having such a configuration is, for example, to form fine grooves in a flat plate of glass, metal, etc. by cutting or etching, and then to inject other materials into the flat plate with these grooves. A method including a step of bonding suitable plates to form a liquid passage, or forming, for example, a groove wall of a cured photosensitive resin on a substrate on which an ejection energy generating element is arranged by a photolithographic process, A method is known that includes a step of providing a groove to serve as a liquid passage on a substrate and bonding another flat plate (cover) to the thus formed grooved plate to form a liquid passage (for example, (Opening No. 57-43876). Among these methods for manufacturing liquid jet recording heads, the latter method using photosensitive resin allows fine processing of liquid passages with higher precision and higher yield than the former method, and is also easier to mass produce. Therefore, it has the advantage that it is possible to provide a liquid jet recording head of good quality and at a lower cost. The photosensitive resins used to manufacture such recording heads are those that have been used for pattern formation in printing plates, printed wiring, etc., or as photocurable paints and adhesives for glass, metals, ceramics, etc. Known resins are used, and dry film type resins have been mainly used from the viewpoint of work efficiency. [Problems to be Solved by the Invention] In a recording head using a cured film of photosensitive resin, in order to obtain excellent characteristics such as advanced recording characteristics, durability, and reliability, it is necessary to The resin has the following properties: (1) it has particularly good adhesion to the substrate as a cured film, (2) it has excellent mechanical strength and durability when cured, and (3) it can be used in a patterned manner. It is required to have characteristics such as excellent sensitivity and resolution during patterning. However, at present, no photosensitive resin has been found that satisfies all of the above-mentioned required characteristics among the photosensitive resins used to form hitherto known liquid jet recording heads. In other words, as a photosensitive resin for recording heads,
Materials used for pattern formation in printing plates, printed wiring, etc. have excellent sensitivity and resolution, but have poor adhesion and adhesion to glass, ceramics, plastic films, etc. used as substrates, and are difficult to harden. Mechanical strength and durability are not sufficient. Therefore, during the manufacturing stage of the recording head or during use, for example, the flow of the recording liquid in the liquid passage may be obstructed, or the direction of droplet ejection may become unstable, resulting in deterioration of the recording characteristics. However, the disadvantage is that the cured resin film is easily deformed, peeled off from the substrate, damaged, etc., which significantly impairs the reliability of the recording head. On the other hand, known photocurable paints and adhesives used for glass, metals, ceramics, etc. have excellent adhesion and adhesion to substrates made of these materials, and have sufficient mechanical strength when cured. Although it has the advantage of being strong and durable, it is inferior in sensitivity and resolution, requiring higher-intensity exposure equipment and longer exposure operations. Since it is not possible to obtain a high-density pattern, this method has the problem that it is not suitable for use in recording heads that require particularly fine precision processing. The present invention was made in view of these problems, and has a liquid passage wall made of a cured resin film that satisfies all the required characteristics as described above, and is inexpensive, precise, and highly reliable. The purpose of the present invention is to provide a liquid jet recording head with excellent durability. Another object of the present invention is to provide a liquid jet recording head having a structure in which liquid passages are microfabricated with high accuracy and high yield. Another object of the present invention is to provide a liquid jet recording head that is highly reliable and has excellent durability even when it is configured with multiple orifices. [Means for Solving the Problems] The above objects can be achieved by the present invention described below. The present invention has a liquid passage communicating with a liquid discharge port, and an ejection energy generating element that generates energy for ejecting the liquid in the liquid passage, and at least a part of the liquid passage is provided with active energy rays. In a liquid jet recording head formed of a cured region of a resin composition that is cured ^by of epoxy groups present in an epoxy resin comprising a certain linear polymer, () a monomer having an ethylenically unsaturated bond, and () at least one compound having two or more epoxy groups in the molecule. A liquid jet recording head characterized in that it is an active energy ray-curable resin composition comprising a resin partially esterified with an unsaturated carboxylic acid. That is, the recording head of the present invention includes a substrate and a cured resin film layer that forms at least grooves serving as liquid passages, and improves the durability of each member constituting the recording head and the adhesiveness between each member. Moreover, the cured resin film layer is microfabricated with high precision, and this recording head has excellent recording characteristics, high reliability, and excellent durability during use. Hereinafter, the liquid jet recording head of the present invention will be explained in detail with reference to the drawings. FIG. 1 shows an example of the liquid jet recording head of the present invention, FIG. 1a is a perspective view of its main parts, and FIG.
1 is a cross-sectional view taken along the line C-C' in FIG. 1a. This liquid jet recording head basically consists of a substrate 1
, a cured resin film 3H provided on the substrate and patterned in a predetermined shape, and a cover 7 laminated on the cured resin film. An orifice 9 for ejecting a liquid, a liquid passage 6-2 communicating with the orifice and having a portion where energy for ejecting the recording liquid acts on the recording liquid, and a recording liquid to be supplied to the liquid passage. A liquid chamber 6-1 for storage is formed. Furthermore, a supply pipe 10 for supplying recording liquid from the outside of the recording head to the liquid chamber 6-1 is connected to the through hole 8 provided in the cover. Note that the supply pipe 10 is omitted in FIG. 1a. During recording, the energy for ejecting the recording liquid is generated by a heating element or a piezoelectric element disposed at a predetermined position in a part of the liquid passage 6-2 that applies ejection energy to the recording liquid. Ejection energy is generated by applying ejection signals as desired to various types of ejection energy generating elements 2, such as elements, via wiring (not shown) connected to these elements. A substrate 1 constituting the recording head of the present invention is made of glass, ceramics, plastic, metal, etc., and a desired number of generating elements 2 are disposed at predetermined positions. In the example shown in FIG. 1, two generating elements are provided, but the number and arrangement of the heating elements are determined as appropriate depending on the predetermined configuration of the recording head. The cover 7 is made of a flat plate made of glass, ceramics, plastic, metal, etc., and is bonded to the cured resin film 3H by fusing or adhesive bonding, and the supply pipe 10 is connected to a predetermined position. A through hole 8 for connection is provided. In the recording head of the present invention, the liquid passage 6-2
The cured resin film 3H patterned into a predetermined shape constituting the wall of the liquid chamber 6-1 is a layer made of a resin composition having the composition described below provided on the substrate 1 or on the cover 7. It is obtained by patterning using a photolithography process. Note that this cured resin film 3H may be patterned integrally with the cover 7 formed of the resin composition. The resin composition used to form the cured resin film provided on the substrate to constitute at least the portion that becomes the liquid passage must: () have a glass transition temperature of 50°C or higher and a weight average molecular weight; An epoxy comprising at least one of a linear polymer having a size of about 3.0×10 ⁴ or more, () a monomer having an ethylenically unsaturated bond, and () a compound having two or more epoxy groups in the molecule. It is an active energy ray-curable resin composition comprising a resin obtained by esterifying a part of the epoxy groups present in the resin with an unsaturated carboxylic acid. It has good adhesion to substrates made of ceramics, etc., has excellent resistance to recording liquids such as ink, and has excellent mechanical strength, and can form precise, high-resolution patterns by patterning with active energy rays. It has excellent properties as a component of a liquid jet recording head. Furthermore, this resin composition can be used as a dry film, and the above-mentioned excellent properties are exhibited in that case as well. Hereinafter, the composition of the active energy curable resin composition used for forming the recording head of the present invention will be explained in detail. The active energy curable resin composition used in the present invention provides suitability for maintaining the composition in the form of a solid film when the composition is used, for example, as a dry film, and has an excellent hardened pattern. Contains as an essential component a linear polymer having a glass transition temperature of 50° C. or higher and a weight average molecular weight of approximately 3.0×10 ⁴ or higher to provide mechanical strength. When the glass transition temperature and weight average molecular weight of the linear polymer are less than the above values, the composition is formed as a solid resin layer on a film base material such as a plastic film, for example, when producing a dry film. During storage, the material gradually flows, causing wrinkles or uneven layer thickness, making it impossible to obtain a good dry film. Specific examples of such linear polymers include, for example, homopolymers having relatively rigid properties;
Monomers that can give the glass transition temperature as above
(A) is the main component, and if necessary, as a second component, (B) a hydroxyl group-containing acrylic monomer, which has hydrophilicity and can impart even better adhesion to the resin composition used in the present invention, (C) Acrylic monomer containing amino or alkylamino group, (D) Acrylic or vinyl monomer containing carboxyl group, (E) N-
Monomers such as vinylpyrrolidone or its derivatives, (F) vinylpyridine or its derivatives,
(G) The following general formula capable of imparting high cohesive strength to the resin composition and improving the mechanical strength of the composition (However, R ¹ is hydrogen or has 1 to 3 carbon atoms.
an alkyl group, R ² is a divalent hydrocarbon group which may have an ether bond therein and may be substituted with a halogen atom, and R ³ is an alkyl group having 3 to 3 carbon atoms.
12 alkyl or phenyl alkyl group or phenyl group. Examples include thermoplastic copolymer polymers obtained by using monomers represented by the following as components of copolymerization within 40 mol%. Specifically, the monomers used as component (A) include alkyl methacrylates in which the alkyl group has 1 to 4 carbon atoms, such as methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, and t-butyl methacrylate; acrylonitrile; Examples include styrene. These monomers are preferably contained in an amount of 60 mol% or more in order to impart the above-mentioned glass transition temperature to the linear copolymer polymer. Specifically, the monomers (B) to (G) above used as the second component include 2-hydroxyethyl (meth)acrylate (hereinafter referred to as (meth)acrylate) as the hydroxyl group-containing acrylic monomer (B). When written as , it is meant to include both acrylate and methacrylate.), 2-
Hydroxypropyl (meth)acrylate, 3-
Chloro-2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, or 1, Examples include monoesters of 4-cyclohexanedimethanol and acrylic acid or methacrylic acid, and the product name is Aronix.
M5700 (manufactured by Toagosei Kagaku Co., Ltd.), TONE M 100 (caprolactone acrylate, union carbide)
Co., Ltd.), Light Ester HO-mpp (Kyoeisha Yushi Kagaku Kogyo Co., Ltd.), Light Ester M-600A (trade name of 2-hydroxy-3-phenoxypropyl acrylate, Kyoeisha Yushi Kagaku Kogyo Co., Ltd.) and dihydric alcohols, such as 1,
10-decanediol, neopentyl glycol,
bis(2-hydroxyethyl) terephthalate,
Monoesters of addition reaction products of bisphenol A and ethylene oxide or propylene oxide, and (meth)acrylic acid can be used. The amino or alkylamino group-containing acrylic monomer (C) includes (meth)acrylamide,
N,N-dimethylaminoethyl (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-dimethylaminopropyl (meth)acrylamide, N,N-di-t-butylaminoethyl (meth)acrylamide, etc. Can be mentioned. Examples of the carboxyl group-containing acrylic or vinyl monomer (D) include (meth)acrylic acid, fumaric acid, itaconic acid, and Toagosei Kagaku Co., Ltd. product names Aronix M-5400 and Aronix M-.
Examples include those known as 5500. (F) vinylpyridine or its derivatives include 2-vinylpyridine, 4-vinylpyridine,
2-vinyl-6-methylpyridine, 4-vinyl-
Examples include 1-methylpyridine, 2-vinyl-5-ethylpyridine, and 4-(4-pipenylinoethyl)pyridine. The above monomers (B) to (F) all have hydrophilic properties, and when the resin composition used in the present invention is bonded to a substrate such as glass, ceramics, or plastic, they provide strong adhesion. It is intended to give. Specifically, the monomer represented by the general formula (G) contains one hydroxyl group in one molecule (α-
Examples include (α-alkyl)acrylic esters having one or more urethane bonds in one molecule, which are obtained by reacting a monoisocyanate compound with an alkyl) acrylic ester. Note that R ² in the monomer represented by the general formula can be any divalent hydrocarbon group that may have an ether bond therein and may be substituted with a halogen atom, but is preferably R ² is an alkylene group having 2 to 12 carbon atoms which may be substituted with a halogen atom, an alicyclic hydrocarbon group such as 1,4-bismethylenecyclohexane, and an aromatic group such as bisphenyldimethylmethane. Examples include hydrocarbon groups containing rings. As the (meth)acrylic ester containing at least one hydroxyl group in one molecule used in producing the monomer represented by the general formula,
2-hydroxyethyl (meth)acrylate, 2
-Hydroxypropyl (meth)acrylate, 3
-Chloro-2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate or light ester Examples include HO-mpp (manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd.). (α-alkyl)acrylic acid esters containing one hydroxyl group in one molecule include (a) esters of aliphatic or aromatic dihydric alcohols and (meth)acrylic acid, and (b) mono- (Meth)acrylic esters of epoxy compounds can likewise be used. The dihydric alcohol used in (a) above is:
1,4-cyclohexanedimethanol, 1,10-
Examples include decanediol, neopentyl glycol, bis(2-hydroxyethyl) terephthalate, and an addition reaction product of 2 to 10 moles of ethylene oxide or propylene oxide to bisphenol A. In addition, as the monoepoxy compound used in the above (b), Epolite M-1230 (trade name,
Kyoeisha Yushi Kagaku Kogyo Co., Ltd.), phenyl glycidyl ether, cresyl glycidyl ether, butyl glycidyl ether, octylene oxide, n
-butylphenol glycidyl ether and the like. In addition, as monoisocyanate compounds used in producing the monomer represented by the general formula, alkyl monoisocyanates formed by adding one isocyanate group to an alkyl group having 3 to 12 carbon atoms, and Examples include enyl isocyanate and cresyl monoisocyanate. The monomer represented by the general formula is preferably contained in the linear copolymer in an amount of up to 40 mol%. If the content exceeds 50 mol%, the softening point of the resulting composition will decrease significantly, and the surface hardness of the pattern obtained by curing the composition will decrease.
This causes problems such as deterioration of chemical resistance due to swelling. The resin composition used for forming the recording head of the present invention is used in various forms such as a solution form or a solid film form when forming the recording head.
It is particularly advantageous to use it in the form of a dry film because it is easy to handle and the film thickness can be easily controlled. Of course, there is no problem in using it in the form of a solution. Although the case where a thermoplastic linear polymer is mainly used has been described above, in the present invention, a linear polymer having thermal crosslinkability or photocrosslinkability can also be used. A thermally crosslinkable linear polymer is, for example, a thermoplastic linear polymer with the following general formula: (However, R ⁴ is hydrogen or has 1 to 3 carbon atoms.
an alkyl or hydroxyalkyl group, R ⁵
represents hydrogen or an alkyl or acyl group which may have a hydroxyl group having 1 to 4 carbon atoms. It can be obtained by introducing a thermally crosslinkable monomer as shown in ) as the second component of copolymerization. The monomer represented by the above general formula not only has thermal crosslinkability but also hydrophilicity, and due to this thermal crosslinkability, it is excellent as a structural material for the resin composition for forming a cured resin film in the present invention. properties,
For example, it exhibits heat resistance, chemical resistance, mechanical strength, etc., and also exhibits excellent adhesion to a substrate due to hydrophilicity. Specifically, the monomers represented by the general formula are N-methylol (meth)acrylamide (hereinafter, when referred to as (meth)acrylamide, it is meant to include both acrylamide and methacrylamide), N -Propoxymethyl (meth)acrylamide, N-n-butoxymethyl (meth)acrylamide, β-hydroxyethoxymethyl (meth)acrylamide, N-ethoxymethyl (meth)acrylamide, N-methoxymethyl (meth)acrylamide, N-acetoxy Methyl (meth)acrylamide, α-hydroxymethyl-N-methylolacrylamide, α-hydroxyethyl-N-butoxymethylacrylamide, α-hydroxypropyl-N-propoxymethylacrylamide, α-ethyl-N-methylolacrylamide, α-propyl -N-methylolacrylamide and other acrylamide derivatives are mentioned. Monomers represented by these general formulas are not only hydrophilic as described above, but also have condensation crosslinking properties when heated, and generally, water molecules or alcohol are released at temperatures of 100°C or higher to form crosslinked bonds, and after curing, The linear polymer itself also forms a network structure, giving the pattern obtained by curing excellent chemical resistance and mechanical strength. When a thermosetting linear polymer is used, it is preferred that the linear polymer contains 5 to 30 mol% of the monomers represented by these general formulas. If the content is within the above range,
Provides sufficient chemical resistance due to heat curing. On the other hand, if the content exceeds 30 mol%, problems such as the pattern obtained by curing will become brittle. In addition to the monomer represented by the above general formula, by appropriately using a thermally ring-opened and crosslinking monomer such as glycidyl (meth)acrylate as a component of the copolymerization, the same as in the case of the above general formula can be obtained. effect can be obtained. The photocrosslinkable linear polymer can be obtained, for example, by methods such as those exemplified below, such as introducing a photopolymerizable monomer into the linear polymer. An example of such a method is to copolymerize a monomer containing a carboxyl group, such as (meth)acrylic acid, or a monomer containing an amino group or a tertiary amine group, and then react it with glycidyl (meth)acrylate, etc. A method, a polyisocyanate partial urethane compound having one isocyanate group and one or more acrylic ester groups in one molecule, and a branched hydroxyl group;
A method of reacting with an amino group or a carboxyl group, a method of reacting a branched hydroxyl group with acrylic acid chloride, a method of reacting a branched hydroxyl group with an acid anhydride, and then reacting with glycidyl (meth)acrylate, Examples of methods include: condensing the hydroxyl group with the condensation-crosslinking monomer exemplified in (F) to leave an acrylamide group on the side chain; and reacting the hydroxyl group of the branched chain with glycidyl (meth)acrylate. When the linear polymer is thermally crosslinkable, it is preferable to perform heating after forming a pattern by irradiation with active energy rays. On the other hand, even in the case of photopolymerizable linear polymers, there is no problem in heating within a range allowable in terms of the heat resistance of the substrate, and in fact, more favorable results can be obtained. The linear polymers used in the resin composition for forming a cured resin film in the present invention are broadly classified into those without curability, those with photocrosslinkability, and those with thermal crosslinkability, as described above. In any case, the step of curing the composition (i.e., pattern formation by active energy ray irradiation and thermal curing as necessary)
In this method, shape retention is imparted to the composition to enable precise patterning, and the pattern obtained by curing has excellent adhesion, chemical resistance, and high mechanical strength. . The monomer () having an ethylenically unsaturated bond used in the resin composition for forming a cured resin film in the present invention, together with the resin component () described later, exhibits curability to the composition by active energy rays. In particular, it is a component for imparting excellent sensitivity to active energy rays to the composition, preferably has a boiling point of 100°C or higher under atmospheric pressure, and preferably has two or more ethylenically unsaturated bonds. It is possible to use various known monomers that are cured by irradiation with active energy rays. Specific examples of such monomers having two or more ethylenically unsaturated bonds include acrylic esters or methacrylic esters of polyfunctional epoxy resins having two or more epoxy groups in one molecule. , acrylic esters or methacrylic esters of alkylene oxide adducts of polyhydric alcohols, polyester acrylates with acrylic ester groups at the molecular chain ends of polyesters with a molecular weight of 500 to 3,000, consisting of dibasic acids and dihydric alcohols, polyhydric alcohols A reaction product of an isocyanate and an acrylic acid monomer having a hydroxyl group can be mentioned. The above monomers ~ may be urethane modified products having a urethane bond in the molecule. Examples of monomers belonging to this category include acrylic acid or methacrylic acid esters of polyfunctional epoxy resins used to produce the component () (half-esterified epoxy resin) of the resin composition of the present invention described later. Examples of monomers belonging to this group include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 1,6 hexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, Examples include pentaerythritol tri(meth)acrylate, and the product names are KAYARAD HX-220, HX-620,
D-310, D-320, D-330, DPHA, R-604,
DPCA−20, DPCA−30, DPCA−60, DPCA−
120 (manufactured by Nippon Kayaku Co., Ltd.), trade name NK ester
BPE-200, BPE-500, BPE-1300, A-BPE
-4 (manufactured by Shin-Nakamura Chemical Co., Ltd.) and the like can be used. Monomers belonging to this category include the product names Aronix M-6100, M-6200, M-6250, M-6300, M
-6400, M-7100, M-8030, M-8060, M-
8100 (manufactured by Toagosei Kagaku Co., Ltd.), etc. Aronix M-
1100, Aronix M-1200 (manufactured by Toagosei Kagaku Co., Ltd.), and the like. Monomers belonging to this group include polyisocyanates and hydroxyl group-containing monomers such as tolylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, and diphenylmethane diisocyanate. Reactants with acrylic monomers are listed, and the product name is Sumidyur N.
(Biuret derivative of hexamethylene diisocyanate), Sumidyur L (trimethylolpropane modified product of tolylene diisocyanate) (the above,
A reaction product obtained by adding a hydroxyl group-containing (meth)acrylic acid ester to a polyisocyanate compound known as Sumitomo Bayer Urethane Co., Ltd.) can be used. The hydroxyl group-containing acrylic monomer mentioned here is typically a (meth)acrylic acid ester, with hydroxyethyl (meth)acrylate and hydroxypropyl (meth)acrylate being preferred. Further, other hydroxyl group-containing acrylic monomers mentioned above for producing monomers represented by the linear polymer formula can also be used. In addition to the monomers having two or more ethylenically unsaturated bonds as described above, monomers having only one ethylenically unsaturated bond, such as those listed below, can also be used. Examples of such monomers having one ethylenically unsaturated bond include carboxyl group-containing unsaturated monomers such as acrylic acid and methacrylic acid; glycidyl group-containing unsaturated monomers such as glycidyl acrylate and glycidyl methacrylate. Monomer; _C2 - _C8 hydroxyalkyl ester of acrylic acid or methacrylic acid such as hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate; polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, polypropylene glycol mono Monoesters of acrylic acid or methacrylic acid and polyethylene glycol or polypropylene glycol such as acrylate, polypropylene glycol monomethacrylate; methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, hexyl acrylate, acrylic Acrylic acids such as octyl acrylate, lauryl acrylate, cyclohexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate, lauryl methacrylate, cyclohexyl methacrylate, etc. or _C1 - _C12 alkyl or cycloalkyl esters of methacrylic acid; other monomers such as styrene, vinyltoluene, methylstyrene, vinyl acetate, vinyl chloride, vinyl isobutyl ether,
Acrylonitrile, acrylamide, methacrylamide, acrylic or methacrylic acid adducts of alkyl glycidyl ethers, vinylpyrrolidone, dicyclopentenyloxyethyl (meth)acrylate, ε-caprolactone modified hydroxyalkyl (meth)acrylate, tetrahydrofurfuryl acrylate, phenolic acid Examples include ethyl acrylate and the like. In any case, by using the above-mentioned monomer having an ethylenically unsaturated bond, the resin composition for forming a cured resin film in the present invention is given sufficient curability with high sensitivity to active energy rays. . A portion of the epoxy groups present in the epoxy resin composed of one or more compounds containing two or more epoxy groups in one molecule used in the resin composition for forming a cured resin film in the present invention is replaced by an unsaturated carboxylic acid. The resin () obtained by esterification (hereinafter referred to as half-esterified epoxy resin) exhibits curability by active energy rays together with the monomer () having the aforementioned ethylenically unsaturated bond in the composition. In addition, when the composition is applied in liquid form onto a substrate such as glass, plastics, ceramics, etc. and then cured to form a cured film, or in the form of a dry film on the substrate. It is a component for imparting better adhesion to a substrate, water resistance, chemical resistance, dimensional stability, etc. to a cured film made of the composition when used in adhesion to a substrate. The half-esterified epoxy resin () contained in the resin composition for forming a cured resin film in the present invention is obtained by adding a predetermined amount of unsaturated carboxylic acid to the epoxy resin in the coexistence of an addition catalyst and a polymerization inhibitor.
In the presence or absence of a solvent, from 80 to
It can be obtained by a method such as esterifying a part of the epoxy groups present in the epoxy resin with a carboxylic acid (half esterification) by reacting at a temperature of 120°C. Examples of epoxy resins containing one or more compounds containing two or more epoxy groups in one molecule that can be used to form half-esterified epoxy resins include bisphenol A, novolac type, and alicyclic type. Representative epoxy resins, bisphenol S, bisphenol F, tetrahydroxyphenylmethane tetraglycidyl ether, resorcinol diglycidyl ether,
Glycerin triglycidyl ether, pentaerythol triglycidyl ether, isocyanuric acid triglycidyl ether and the following general formula (However, R is an alkyl group or an oxyalkyl group, R ₀ is

【formula】

〔Effect of the invention〕

In the liquid jet recording head of the present invention, an active energy ray-curable resin composition that is a component of the head is half-esterified with a monomer having an ethylenically unsaturated bond contained as an essential component in the composition. The pattern-forming material that is mainly applied by epoxy resin has excellent sensitivity and resolution, and by using this resin composition, a liquid jet recording head with excellent dimensional accuracy can be created. It has become possible to obtain it with good yield. Moreover, the resin composition used in the present invention effectively utilizes the characteristics of the linear polymer and half-esterified epoxy resin as essential components. In addition to the excellent adhesion to the substrate and mechanical strength provided by the polymer, it also has excellent chemical resistance and dimensional stability mainly provided by the half-esterified epoxy resin. By using this composition, it has become possible to obtain a recording head with long-term durability. Furthermore, when a linear polymer having curability is used, it is possible to obtain a liquid jet recording head particularly excellent in the above-mentioned adhesion, mechanical strength, or chemical resistance. [Example] Hereinafter, the present invention will be explained in more detail with reference to Synthesis Examples and Examples. Synthesis example Methyl methacrylate, t-butyl methacrylate, and dimethylaminoethyl methacrylate (=70/20/10 molar ratio) were solution polymerized in toluene to give a weight average molecular weight of 7.8×10 ⁴ and a glass transition temperature.
Linear polymer compound at 89℃ (this is called LP-1)
I got it. Also, Epiclon 855, a bisphenol A type with an epoxy equivalent of 183 to 193 (Dainippon Ink & Chemicals Co., Ltd.)
), 4 g of triethylbenzylammonium chloride as a catalyst, and 0.5 g of hydroquinone as a thermal polymerization inhibitor was heated to 80°C, and while adding dropwise 0.5 equivalent of acrylic acid per equivalent of epoxy group present. Made it react. After dropping the acrylic acid, stirring was continued for another 4 hours to complete the reaction. In this way, an epoxy half ester (referred to as HE-1) in which the epoxy group was partially acrylic esterified was obtained. Linear polymer compound obtained as above
An active energy ray-curable resin composition having the following composition was prepared using LP-1 and epoxy half ester HE-1. LP-1 100 parts by weight HE-1 80 〃 Aronik M8060*1 120 〃 Irgakiure 651 10 〃 Crystal Violet 0.5 〃 t-Butylhydroquinone 0.5 〃 1:1 mixture of MIBK/toluene 300 〃 *1: Polyester acrylate (Toagosei Co., Ltd.) chemistry
Co., Ltd.) Next, the above resin composition was applied to a 16 μm polyethylene terephthalate film using a wire bar and dried at 100°C for 20 minutes to obtain a film with a thickness of 75 μm.
A dry film according to the present invention having a resin composition layer was prepared. Example Using the dry film produced in the synthesis example, a heating element [hafnium boride (HfB ₂ )] 10 was prepared as an ejection energy generating element according to the steps shown in FIGS. 1 to 6 described earlier in the specification. Orifice (orifice dimensions: 75μm x 50μm, pitch 0.125
An on-demand liquid jet recording head having a diameter of 1 mm) was fabricated as follows. Note that 30 recording heads of the same shape were prototyped for each type. First, a plurality of heating elements were arranged at predetermined positions on a substrate made of silicon, and recording signal application electrodes were connected to these heating elements. Next, _two layers of SiO (thickness: 1.0 μm) are provided as a protective film on the surface of the substrate on which the heating element is arranged, and after cleaning and drying the surface of the protective layer, it is stacked on the protective layer. Film thickness shown in synthesis example heated to 80℃
75 μm dry film at a speed of 0.4 f/min.
Lamination was carried out under pressure conditions of Kg/cm ³ . Next, a photomask having a pattern corresponding to the shapes of the liquid passages and liquid chambers is superimposed on the dry film provided on the substrate surface, and the above-mentioned elements are positioned so that they are installed in the liquid passages that are finally formed. After alignment, the dry film was exposed to ultraviolet light at an intensity of 12 mW/cm ² for 60 seconds from the top of the photomask. Next, the exposed dry film is 1, 1,
Immersed in 1-trichloroethane and developed,
The unpolymerized (uncured) portion of the dry film was dissolved and removed from the substrate, and the cured dry film film remaining on the substrate formed grooves that would eventually become liquid passages and liquid chambers. After the development process was completed, the cured dry film on the substrate was heated at 150° C. for 1 hour, and further cured by irradiating it with ultraviolet rays at an intensity of 50 mW/cm ² for 2 minutes. In this way, after forming grooves that will become liquid passages and liquid chambers on the substrate using the cured dry film film, epoxy resin is applied to a flat plate with through holes made of soda glass that will cover the formed grooves. After spin-coating the adhesive to a thickness of 3 μm, preheating it to B-stage, bonding it onto the cured dry film, and then fully curing the adhesive and fixing it to form a bonded body. . Next, the downstream side of the liquid passage of the bonded body, that is, the downstream side from the installation position of the discharge energy generating element.
A commercially available dicing saw (product name: DAD2H/6
A mold (manufactured by DISCO) was used to cut it to form an orifice for discharging the recording liquid. Finally, the cut surface was cleaned and dried, and the cut surface was polished to make it smooth, and a recording liquid supply pipe was attached to the through hole to complete the liquid jet recording head. All of the obtained recording heads had excellent dimensional accuracy and had liquid passages and liquid chambers that faithfully reproduced the mask pattern. Incidentally, the orifice dimensions were in the range of 50±5 μm and the orifice pitch was in the range of 125±5 μm. The quality and durability of the thus prototyped recording head during long-term use were tested in the following manner. First, the obtained recording head was subjected to a durability test in which it was immersed in a recording liquid having the following composition at 60° C. for 1000 hours (environmental conditions comparable to those during long-term use of a recording head). Recording liquid components (1) H ₂ O / diethylene glycol / polyethylene glycol # 300 / Sulfolane / CI Direct Blue 86 ^*1 (= 60 / 15 / 10 / 10 / 5 parts by weight) PH = 8.0 (2) H ₂ O / Diethylene glycol/Polyethylene glycol #300/Propylene glycol/
CI Direct Blue 86 (=62/15/15/5/3 parts by weight) PH=9.0 (3) H ₂ O / Triethylene Glycol / Glycerin / CI Food Black 2 ^*2 / Emulgen
931 ^*4 /PVP K-30 ^*5 (=80/15/2/3/0.1/0.1 parts by weight) PH=7.0 (4) H ₂ O/Ethylene glycol/Diethylene glycol/Propylene glycol/CI Direct Black 154 ^*3 / Emulgen 931 (=64/20/5/5/6/0.2 parts by weight) PH=
10.0 Note: ^*1 to ^*3 are water-soluble dyes, ^*4 is Kao Soap Co., Ltd.
Polyoxyethylene nonyl phenyl ether manufactured by ^*5 Polyvinylpyrrolidone manufactured by GAF in the United States, and caustic soda was used to adjust the pH. For each recording liquid, five recording heads were subjected to a durability test. After the durability test, we observed the state of bonding between the substrate and cover and the cured dry film film for each head tested. As a result, no peeling or damage was observed in any of the recording heads, indicating good adhesion. . Then separately 10 of the obtained recording heads
For each head, attach each head to a recording device, and use the recording liquid described above to record a recording signal of ¹⁰⁸ pulses at 14
A printing test was carried out in which printing was performed by applying power to the recording head continuously over time. With respect to any of the recording heads, almost no deterioration was observed in both recording liquid ejection performance and printing condition immediately after printing started and after 14 hours had elapsed, indicating that the recording heads had excellent durability. Comparative Examples A commercially available dry film Vacrel (trade name of dry film solder mask, manufactured by DuPont Nemo Earth Co., Ltd.) with a film thickness of 75 μm, and a commercially available dry film Photoc SR-3000 (trade name, manufactured by Hitachi Chemical Co., Ltd.) with a film thickness of 50 μm A recording head was prepared in the same manner as in the example except that a recording head (manufactured by Co., Ltd.) was used. Durability tests similar to those in the examples were conducted on these recording heads. During the durability test, as a dry film
When Vacrel was used, peeling was observed with recording liquids (2) and (4) after 100 hours. Furthermore, after 300 hours, peeling was observed with the recording liquids (1) and (3). On the other hand, as a dry film, Photoc SR−
3000, each of the recording liquids (1) to (4)
Peeling was observed after 300 hours. Printing test example Heads prepared in Examples and Comparative Examples (10 prints each)
A recording liquid having the composition listed above in 4) was filled into each of the test pieces, and a printing test was conducted. Next, each head filled with the recording liquid was stored for 200 hours at a temperature of 80° C. and a humidity of 90%, and then a printing test similar to that previously conducted was conducted. As a result, good printing was obtained in all 10 heads obtained in the example before and after storage, whereas poor printing was observed in all of the heads in the comparative example. When these defective print areas were observed under a microscope, it was observed that the recording droplets forming the characters were misaligned. Further, when observing the vicinity of the ejection opening of each head where printing defects occurred, peeling was observed in the dry film cured film in that area.

[Brief explanation of drawings]

1 to 6 are schematic diagrams for explaining the liquid jet recording head of the present invention and its manufacturing method. 1: Substrate, 2: Discharge energy generating element, 3:
Resin layer, 3H: Resin cured film, 4: Photomask,
4P: Mask pattern, 6-1: Liquid chamber, 6-2:
Liquid passage, 7: cover, 8: through hole, 9: orifice, 10: supply pipe.

Claims (1)

[Scope of Claims] 1. A liquid passageway communicating with a liquid discharge port, and a discharge energy generating element that generates energy for discharging the liquid in the liquid passageway, wherein at least a portion of the liquid passageway is In a liquid jet recording head formed of a cured region of a resin composition that is cured by active energy rays, the resin composition () has a glass transition temperature of 50° C. or higher and a weight average molecular weight of about 3.0×10 present in an epoxy resin comprising at least one of the ^following : () a monomer having an ethylenically unsaturated bond; and () a compound having two or more epoxy groups in the molecule. 1. A liquid jet recording head comprising a resin obtained by esterifying a portion of an epoxy group with an unsaturated carboxylic acid. 2 The resin composition is the linear polymer 20 of the above ()
~80 parts by weight, the monomer of the above () and the above ()
The liquid jet recording head according to claim 1, wherein the liquid jet recording head contains a total amount of 80 to 20 parts by weight of the resin. 3. The liquid jet recording head according to claim 1 or 2, wherein the content ratio of the () monomer and the () resin in the resin composition is 30:70 to 70:30. . 4. The resin composition is the linear polymer of () above,
0.1 to 20% by weight of a radical polymerization initiator that can be activated by the action of active energy rays is blended with 100 parts by weight of the monomer () and the resin (). A liquid jet recording head according to any one of claims 1 to 3. 5 The resin composition is the linear polymer of () above,
A photosensitive aroma containing 0.2 to 15% by weight of an element belonging to group a or group a of the periodic table based on 100 parts by weight of the monomer of the above () and the resin of the above () A liquid jet recording head according to any one of claims 1 to 4, which contains a group onium salt compound. 6. A liquid jet recording head according to any one of claims 1 to 5, wherein the ejection energy generating element is a heat generating element.