JP6584207B2 - Liquid discharge head and manufacturing method thereof - Google Patents

Description

  The present invention relates to a liquid discharge head that discharges liquid such as ink and a method for manufacturing the same.

Recording and surface treatment of characters, images, etc. by a liquid discharge head typified by an ink jet recording head gives thermal energy or vibration energy to the liquid such as ink, and discharges the liquid as fine droplets from the discharge port to be recorded. This is done by applying a liquid to a predetermined position of the medium. A method of manufacturing such a liquid discharge head is described in Patent Document 1.
In the manufacturing method disclosed in Patent Document 1, first, a recording element substrate having an ejection port, a flow path, an ejection energy generating element and the like is attached to a support plate such as alumina, and the recording element substrate and a flexible wiring substrate as an electric wiring member Are electrically joined. Next, a peripheral sealing material is applied to protect the side surface of the recording element substrate from ink and dust. After the surrounding sealing material is cured, an ILB (inner lead bonding) sealing material (electrical connection portion sealing material) for sealing the electrical connection portion is applied from above.
The functions required for each of the peripheral sealing material for sealing the periphery of the recording element substrate and the electrical connection portion sealing material used here are as follows.
As the surrounding sealing material, 1 mm formed between the part on the support plate and the recording element substrate.
It is required to flow in a narrow gap in a short time and be filled quickly. In addition, it is required to protect the recording element substrate from ink and other factors.
As the electrical connection portion sealing material, not only the electrical connection portion is sealed, but also the contact with the paper or the like by rubbing with a blade or wiper for cleaning the ink discharge port arrangement surface or paper jam. It is required that the stopper is not peeled off.

Patent Document 2 describes a method of increasing production efficiency by simultaneously curing the peripheral sealing material and the electrical connection portion sealing material. That is, Patent Document 2 discloses that the hardness after curing of the electrical connection portion sealing material is higher than the hardness after curing of the surrounding sealing material, and the main component of the material of the electrical connection portion sealing material and the surrounding sealing material. In addition, a method of coating and laminating these with the same curing agent is described.
By this method, even if the surrounding sealing material and the electrical connection portion sealing material are simultaneously cured, there is no contention (curing inhibition) of the curing agent between the both sealing materials due to the difference in curing speed of each sealing material. .
In Cited Document 3, in order to obtain good adhesion between the recording element substrate and the surrounding sealing material, and good adhesion between the surrounding sealing material and the electrical connection portion sealing material, both epoxy resin having a butadiene skeleton and A sealing material containing a curing agent and having a low elastic modulus in a cured state is used as the peripheral sealing material.

  Patent Document 4 is useful as a raw material for visible light curable resins, UV curable resins, electron beam curable resins, adhesives, modifiers, coating agents, and the like, and has water resistance, electrical insulation, moisture resistance, and weather resistance. A polyisobutylene-based polymer having a functional group at a terminal excellent in various properties such as heat resistance and heat resistance is described.

JP 2002-019120 A JP 2005-132102 A Patent No. 5005069 Japanese Patent Laid-Open No. 7-102017

In recent years, liquid discharge heads capable of printing high-definition images at high speed have been required to be provided to the market at a low price.
In order to record a high-definition image in a liquid discharge head, it is effective to increase the integration density of discharge energy generating elements to increase the density. It is also an effective means to use ink having high color developability. In order to perform high-speed printing, it is also effective to increase the number of energy generating elements and lengthen the liquid discharge head.
In the case of a long liquid discharge head extending in the width direction of the recording surface of the recording medium [lateral direction orthogonal to the paper feed direction (vertical direction of the recording medium)], for example, a full line type liquid discharge head, the width direction of the recording medium No operation for scanning the liquid discharge head is required. Therefore, it is possible to simplify the structure of the recording apparatus and reduce the price of the recording apparatus.
In the long liquid discharge head, the recording element substrate is enlarged, and the capacity of the sealing material around the recording element substrate and the sealing material in the electrical connection portion between the recording element substrate and the electric wiring member is increased. For this reason, the durability of the sealing portion by the sealing material is one of the important requirements for improving the reliability of the liquid discharge head. For example, in the case of a thermosetting encapsulant, if the stress generated when thermosetting the encapsulant applied in liquid form increases with an increase in the use capacity of the encapsulant, the recording element substrate side There are cases where cracks or cracks in the sealing portion occur.
On the other hand, it is effective to increase the dispersibility and solubility of coloring materials such as pigments and dyes in water-based inks in order to increase the color developability when coloring with water-based inks. For this reason, the amount of solvents other than water is increased. Or addition of a new solvent may be necessary. Such a solvent other than water, for example, a water-soluble organic solvent may affect the sealing portion, and may cause swelling of the sealing portion, a decrease in adhesiveness, and the like. The swelling of the sealing portion and the decrease in adhesiveness may lead to a decrease in reliability such as a decrease in electrical characteristics of the liquid discharge head. Furthermore, when the amount of liquid discharged from one liquid discharge head increases, the amount of liquid that comes into contact with the sealing portion during a cleaning operation using wiping increases, and the amount of liquid that comes into contact with the sealing portion due to a solvent other than water contained in the liquid increases. The impact will also increase. In the long liquid discharge head, the wiping application area at the time of cleaning using wiping is further increased, the amount of liquid in contact with the sealing portion is also increased, and the sealing portion is made of a solvent other than water contained in the liquid. The effect of will be even greater. Therefore, the sealing material used for the liquid discharge head is required to be able to form a sealing portion having resistance to not only water contained in liquid such as water-based ink but also solvents other than water.
However, Patent Documents 1 to 4 do not disclose the technical problems related to the sealing material described above.
The object of the present invention is to provide a long-term durability for a sealing portion made of a sealing material, even when a recording element substrate elongated at a high density or an aqueous liquid is discharged, and is reliable. It is an object of the present invention to provide a liquid discharge head and a manufacturing method thereof.

The liquid discharge head according to the present invention is
A recording element substrate comprising: a discharge member that discharges liquid; a flow path member that has a flow path that supplies liquid to the discharge port; and a substrate that includes an discharge energy generating element that generates energy for discharging liquid from the discharge port. When,
An electrical wiring member for transmitting a signal for driving the ejection energy generating element;
An electrical connection for electrically connecting the recording element substrate and the electrical wiring member;
Have
A first sealing material that seals a lower region of the electrical connection portion; a second sealing material that seals an upper region of the electrical connection portion;
A liquid ejection head comprising:
The first sealing material is
(A) a polyisobutylene compound having at least two alkenyl groups in one molecule;
(B) a compound having at least two hydrosilyl groups in one molecule;
(C) a hydrosilylation catalyst , and
(D) Ri sealing material A der curable contain plasticizers <br/>,
The second sealing material is
(A) a polyisobutylene compound having at least two alkenyl groups in one molecule;
(B) a compound having at least two hydrosilyl groups in one molecule;
(C) a hydrosilylation catalyst, and
(E) thixotropic agent
A curable encapsulant B containing, and
(I) an epoxy resin, a glycidyl ester resin, a glycidyl amine resin, a silicone-modified product thereof, a polybutadiene-modified product, a urethane-modified product, and a main agent selected from those obtained by polyfunctionalizing these,
(ii) a curing agent, and
(iii) Filler
It is any one of the sealing materials C containing these.

A method for manufacturing a liquid discharge head according to the present invention includes:
A recording element substrate comprising: a discharge member that discharges liquid; a flow path member that has a flow path that supplies liquid to the discharge port; and a substrate that includes an discharge energy generating element that generates energy for discharging liquid from the discharge port. When,
An electrical wiring member for transmitting a signal for driving the ejection energy generating element;
An electrical connection for electrically connecting the recording element substrate and the electrical wiring member;
A method of manufacturing a liquid discharge head having
The sealing position of the electrical connection portion is a lower region and an upper region of the electrical connection portion,
Filling a lower region of the electrical connection portion with a first sealing material;
A step of laminating a second sealing material for sealing the upper region of the electrical connection portion on the first sealing material filled in the lower region of the electrical connection portion so as to cover the electrical connection portion. When,
Curing the first sealing material;
Curing the second sealing material;
Have
The first sealing material is
(A) a polyisobutylene compound having at least two alkenyl groups in one molecule;
(B) a compound having at least two hydrosilyl groups in one molecule;
(C) a hydrosilylation catalyst , and
(D) Ri sealing material A der curable contain plasticizers <br/>,
The second sealing material is
(A) a polyisobutylene compound having at least two alkenyl groups in one molecule;
(B) a compound having at least two hydrosilyl groups in one molecule;
(C) a hydrosilylation catalyst, and
(E) thixotropic agent
A curable encapsulant B containing, and
(I) an epoxy resin, a glycidyl ester resin, a glycidyl amine resin, a silicone-modified product thereof, a polybutadiene-modified product, a urethane-modified product, and a main agent selected from those obtained by polyfunctionalizing these,
(ii) a curing agent, and
(iii) Filler
It is any one of the sealing materials C containing these.

The sealing portion of the liquid discharge head formed by the sealing material according to the present invention has a polyisobutylene chain, has a high insulating property, is soft and flexible, and has a large elongation. Therefore, even if there is a large difference in thermal expansion from the recording element substrate member on which the sealing portion is formed, the stress generated during thermal curing or repeated use of the sealing material is small, and cracking or sealing on the recording element substrate side Occurrence of peeling or cracking on the part side can be prevented, and a liquid ejection head with high reliability of the sealing part can be provided.
Furthermore, the sealing part containing a polyisobutylene chain has resistance to water or a solvent other than water contained in an aqueous liquid such as an aqueous ink, and prevents swelling or peeling of the sealing material due to the influence of these components. Can do.

It is a figure which shows typically the structure of a liquid discharge head. It is a top view of the liquid discharge head which shows typically the sealing process concerning the present invention.

A liquid discharge head according to the present invention includes a recording element substrate and an electric wiring member for transmitting a signal for driving the discharge energy generating element, and the recording element substrate and the electric wiring member are interposed via an electric connection portion. Are electrically connected.
The recording element substrate includes a flow path member having a discharge port for discharging a liquid and a flow path for supplying the liquid to the discharge port, and a discharge energy generating element for generating energy for discharging the liquid from the discharge port.
The ejection energy generating element is driven by inputting an electric signal from the electric wiring member. Various connection methods can be used to form the electrical connection portion between the ejection energy generating element disposed in the recording element substrate and the electrical wiring member outside the recording element substrate. For example, the electrical connection portion can be formed by electrically joining the leads of the electrical wiring member and the terminals of the wiring connected to the ejection energy generating elements in the recording element substrate, such as electrode pads and bumps. .

In the present invention, as a sealing material for sealing at least the electrical connection portion of the liquid discharge head,
(A) a polyisobutylene compound having at least two alkenyl groups in one molecule;
(B) a sealing material (hereinafter, referred to as “polyisobutylene-based sealing material”) comprising a curable composition containing at least two hydrosilyl groups in one molecule and (c) a hydrosilylation catalyst. Used.
The polyisobutylene compound as the component (a) is a compound having a polyisobutylene chain and at least two alkenyl groups in one molecule, and is blended in a sealing material as a main agent. Preferably, a compound having an alkenyl group at both ends and having a number average molecular weight of about 3000 to 50000 is preferably used. These are preferable in terms of reactivity and viscosity in handling. As the polyisobutylene compound, a known or commercially available polyisobutylene liquid resin that is used or can be used as a main component of a curable resin used as an adhesive or a coating agent can be selected and used. Commercially available products include Epion 200A, Epion 400A, Epion 600A (manufactured by Kaneka), and the like.
The compound having at least two hydrosilyl groups (SiH) in the molecule as the component (b) reacts with the component (a) in the presence of the hydrosilylation catalyst as the component (c) as a sealing material. There is no particular limitation as long as it can function as a curing agent for forming a cured product that satisfies the characteristics.
Examples of the compound having at least two hydrosilyl groups (SiH) in one molecule as the component (b) include polyorganohydrogensiloxane having at least two hydrosilyl groups in one molecule. Since the hydrosilyl group contributes to the curing reaction, if the number in one molecule is large, the composition itself becomes unstable, and if it remains in the cured product, the physical properties deteriorate. Therefore, the number of hydrosilyl groups in one molecule Is preferably 35 or less. As the component (b), a known or commercially available compound that can be used as a curing agent for the polyisobutylene compound as the component (a) or is used can be used. Examples of commercially available products include “HMS301” (trade name, methylhydrosiloxane-dimethylsiloxane copolymer, manufactured by Asmax).
The blending ratio of the component (a) and the component (b) is a physical property as a target sealing material, preferably tensile elongation, hardness shore A, thermal expansion coefficient, volume resistivity, mass in Examples 1 to 4 described later. The rate of change can be selected. For example, the amount of the hydrosilyl group in the curing agent added to the encapsulant as the component (b) is such that the hydrosilyl group is 0.5 to 5 mol with respect to 1 mol of the alkenyl group of the component (a). preferable. The molecular weight of the curing agent is preferably in the range of 100 to 30000.
The hydrosilylation catalyst as the component (c) is not particularly limited as long as it can polymerize the component (a) and the component (b) by a hydroxylylation reaction, and has a hydrosilylation reaction catalytic activity. You can choose from materials. Specific examples of the component (c) include platinum organometallic complexes such as platinum alone, chloroplatinic acid, platinum olefin complexes, and platinum alcoholate complexes. (C) What is necessary is just to mix | blend component (c) with a sealing material with the catalyst amount for obtaining the target hardening reaction.

The polyisobutylene-based sealing material is not particularly limited as a stabilizer, if necessary. Specifically, the thiophene compound, imino compound, compound having an aliphatic unsaturated bond, organic phosphorus compound, organic A sulfur compound or the like can be added.
Furthermore, additives such as adhesion improvers such as silane coupling agents, process oils and olefin oligomers, antioxidants, and fillers for the purpose of viscosity reduction can be added to the polyisobutylene-based sealing material as necessary. .
The polyisobutylene-based sealing material has curability, and in particular, a cured product having a good specification as a sealing portion can be provided by thermal curing.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment)
FIG. 1A is a schematic view of an ink jet recording head (hereinafter referred to as “recording head”), which is an embodiment of a liquid ejection head, as viewed from the direction in which ink is ejected. FIG.1 (b) is AA fragmentary sectional drawing in Fig.1 (a). FIG. 1C is a partial cross-sectional view along the lead arrangement direction schematically showing the structure of the sealed electrical connection portion.
The illustrated recording head has a configuration in which two ink supply ports 9 are provided on one substrate 1 and four ejection port arrays in which the ejection ports 3 are arranged by the flow path member 4 are arranged. The same type of ink filled in the two ink supply ports 9 is ejected from the ejection port 3 by applying energy from the ejection energy generating element 2.
As for the electrical connection portion, the lead 6 on the side of the electrical wiring member 5 such as a flexible wiring board and the terminals 10 (for example, pads, bumps, etc.) of the connection wiring to the ejection energy generating element on the recording element substrate 14 side are electrically connected. It is formed by joining.
The recording element substrate 14 is installed and fixed at a predetermined position in the opening formed by the lateral peripheral sealing portion 8 fixed on the support member 7.

As a region below the lead 6 formed by the periphery of the recording element substrate 14, that is, the side surface of the recording element substrate 14, the inner side surface of the lateral peripheral sealing portion 8, and the surface of the support member 7, that is, a lower region of the electrical connection portion The peripheral sealing material 12 as the first sealing material is filled in the recess. A region above the lead 6, that is, an upper region of the electrical connection portion is sealed with an electrical connection portion sealing material 13 as a second sealing material. The peripheral sealing material 12 and the electrical connection portion sealing material 13 are laminated in a region surrounding the electrical connection portion, that is, the second sealing material is covered on the first sealing material and the electrical connection portion is covered. The electrical connection portion is surrounded and sealed by the laminated structure.
A polyisobutylene-based sealing material is used to form at least the lower region of the lead 6 of the peripheral sealing material 12. A structure in which the lower region of the lead 6 is also sealed with the peripheral sealing material 12 as in the structure of the liquid discharge head shown in the drawing is preferable for improving the efficiency of the sealing process, and the polyisobutylene system is also used as the peripheral sealing material 12. It is preferable to use a sealing material.
Since the peripheral sealing material 12 has to flow around the lower region of the lead 6 and the recording element substrate 14, low viscosity and low thixotropy are required. Therefore, the viscosity and thixotropic property of the polyisobutylene-based sealing material as the peripheral sealing material can be selected from the low viscosity range and the low thixotropic property range used in the peripheral sealing material.

The polyisobutylene-based sealing material can also be used as the electrical connection portion sealing material 13.
Since the electrical connection portion sealing material 13 has a function of protecting the lead 6, it requires a high elastic modulus (high hardness). Therefore, it is preferable to highly fill a filler such as silica. In order to leave the electrical connection portion sealing material 13 on the lead 6, it is necessary to impart thixotropy to the electrical connection portion sealing material 13. In addition, it is preferable to impart thixotropy after having a certain degree of fluidity. Therefore, the viscosity and thixotropy of the electrical connection portion sealing material 13 can be selected from the high viscosity range and the high thixotropy range used in the electrical connection portion sealing material.
When using a polyisobutylene-based sealing material as the electrical connection portion sealing material 13, when a filler is added, it is preferable to use a filler capable of imparting thixotropy as a thixotropic agent. Examples of such a filler include fumed silica produced by a dry method typified by Aerosil (trade name: Nippon Aerosil). By using such a filler, the electrical connection portion sealing material 13 can be used. Not only thixotropy but also its mechanical properties are improved. Thus, it is preferable that the electrical connection part sealing material 13 contains a thixotropic agent as (d) component.

As the electrical connection portion sealing material 13, other sealing materials other than the polyisobutylene-based sealing material can also be used. As the other sealing material, a sealing material used for covering and sealing the electrical connection portion of the liquid discharge head can be used.
Examples of the main agent of other sealing material, bisphenol type epoxy resins, bromine-containing epoxy resin, phenol or cresol-based epoxy resins, cyclic aliphatic epoxy resins, grayed glycidyl ester resins, glycidyl amine resins, heterocyclic And epoxy resins, modified silicone products, modified polybutadiene products, modified urethane products, and those obtained by polyfunctionalizing these with pentaerythritol, trimethylolpropane, glycerin, and the like.
An epoxy resin sealing material containing a main agent having at least an epoxy group as a polymerizable group is particularly preferable because it has excellent chemical resistance.

The curing agent in the other sealing material can be selected in consideration of compatibility with the main agent according to the type of the main agent. Examples thereof include amine-based curing agents, acid and acid anhydride-based curing agents, resol type phenol resins having hydroxyl groups in epoxy resins as crosslinking points, urea resins, melamine resins, isocyanates, and blocked isocyanates.
Examples of the amine curing agent include aliphatic amines such as ethylenediamine (EDA), aliphatic aromatic amines such as m-xylenediamine, aromatic amines such as metaphenylenediamine (MPDA), and polyaminoamides.
Examples of the acid and acid anhydride curing agents include aliphatic acid anhydrides such as dodecenyl succinic anhydride (DDSA), alicyclic acid anhydrides such as methyltetrahydrophthalic anhydride (Me-THPA), and phthalic anhydride (PA). ) And other halogen-based acid anhydrides such as het anhydride (HET).
The compounding quantity of a hardening | curing agent is not specifically limited, It can select from the range which can obtain the hardening state by the target main ingredient.

A filler can also be added to other sealing materials for the purpose of adjusting hardness, thixotropy, shape maintaining property, viscosity, and the like. Examples of the filler include silica, carbon black, titanium oxide, kaolin, clay, and calcium carbonate.
The filling amount of the filler in the other sealing material, that is, the filler content relative to the whole sealing material can be selected according to the physical properties of the target sealing material. Although it varies depending on the type of filler, particle shape, particle size and the like, it can be selected from the range of 50 to 80% by mass with respect to the entire encapsulant according to the characteristics of the target encapsulant.
Additives and the like may be added to other sealing materials in order to improve various performances. Examples of additives include silane coupling agents to improve adhesion to inorganic materials such as silicon wafers, defoamers to improve defoaming, and promotion or control of viscosity and reactivity. An amine, a reactive monomer, a catalyst, etc. for adjusting this can be mentioned.

The recording head shown in FIG. 1 can be manufactured by the following method.
The recording element substrate 14 is installed and fixed at a predetermined position in the opening formed by the lateral peripheral sealing portion 8 fixed on the support member 7. Next, the terminal 10 of the wiring for sending a signal to the ejection energy generating element 2 of the recording element substrate 14 and the lead 6 of the electric wiring member 5 are joined to form an electrical connection portion. A well-known method can be used for these joining.
The state at this stage is shown in the schematic plan view of FIG. A recess 11 serving as a sealing position is formed between the side surface of the recording element substrate 14 and the inner side surface of the lateral peripheral sealing portion 8 positioned below the electric wiring member 5 by these side surfaces and the surface of the support member 7. Is formed.
The recess 11 is filled with the surrounding sealing material 12. Since the surrounding sealing material cannot be directly filled into the lower region of the lead 6 by a dispenser or the like, the surrounding sealing material is filled from the side of the lead 6 into the lower region of the lead 6. A schematic plan view of FIG. 2B shows a state in which the recess 11 is filled with the peripheral sealing material.
After the surrounding sealing material 12 is thermally cured, as shown in FIG. 1C, the electrical connection portion sealing is performed on the connection portion between the terminal 10 and the lead 6 as a sealing position, that is, the electrical connection portion upper region. Cover with material 13 and cure. At this stage, a portion in which a layer of the cured product of the first sealing material and a layer of the cured product of the second sealing material are laminated is generated.
In the stage shown in FIG. 2B, the surrounding sealing material 12 is not thermally cured, but the upper region of the lead 6 is covered with the electrical connection portion sealing material 13, and then these are thermally cured at the same time. You may let them. By using the peripheral sealing material 12 and the electrical connection portion sealing material 13 having common thermosetting conditions, this simultaneous thermosetting treatment can be performed, and the sealing process can be made efficient. In this case, in the surrounding sealing material 12 and the electrical connection portion sealing material 13, the main agent and the curing agent may be the same or different.

Since the polyisobutylene-based encapsulant has a polyisobutylene chain, the cured product has high insulating properties, is soft and flexible, has high elongation, and has excellent water resistance and solvent resistance. . By using the polyisobutylene-based sealing material as the surrounding sealing material of the recording element substrate, the generation of stress during thermosetting of the sealing material is reduced, and cracks on the recording element substrate side and in the sealing portion Breaking and peeling can be prevented. In addition, in a liquid discharge head that discharges an aqueous liquid such as an aqueous ink, it is possible to eliminate the influence on the sealing portion due to moisture and solvent components contained in the aqueous liquid adhering to the peripheral sealing portion.
On the other hand, by using a polyisobutylene-based sealing material as an electrical connection portion sealing material, it is possible to prevent cracking on the recording element substrate side during thermal curing on the electrical connection portion, and cracking or peeling off at the sealing portion. Furthermore, it is possible to eliminate the influence on the sealing portion due to moisture and solvent components contained in the aqueous liquid adhering to the sealing portion covering the electrical connection portion.
Therefore, by using the polyisobutylene-based sealing material, long-term durability can be obtained in the sealing portion of the liquid discharge head, and the reliability of the liquid discharge head can be further improved.
The polyisobutylene-based sealing material is particularly preferably used for forming a sealing portion in a long liquid discharge head.

Hereinafter, the present invention will be further described using examples and comparative examples. Example 1 is a reference example.
(Examples 1-4, Comparative Examples 1-2)
The components shown in Table 1 were mixed to obtain sealing materials 1 to 4 as polyisobutylene-based sealing materials.

“Epion 400A” (trade name, manufactured by Kaneka Co., Ltd.) as a component is a liquid resin having a polyisobutylene skeleton in the main chain and alkenyl groups at both ends, and has at least two alkenyl groups in one molecule. It corresponds to the polyisobutylene compound having.
“HMS301” (trade name, manufactured by Azmax) as the component (b) is a methylhydrosiloxane-dimethylsiloxane copolymer and corresponds to a compound having at least two hydrosilyl groups in one molecule.
(C) Chloroplatinic acid hexahydrate as a component is a hydrosilylation catalyst.
“Diana Process Oil PW32” (trade name, manufactured by Idemitsu Kosan Co., Ltd.) is a paraffinic process oil as a plasticizer. “Aerosil R972” (trade name, manufactured by Nippon Aerosil) is fumed silica as a thixotropic agent.
In the preparation of each composition, as is generally done, since the catalyst is particularly low in dispersibility, it was dissolved in ethanol and then mixed with other components, followed by depressurization and the like to remove moisture and the like that became a catalyst poison.
The sealing material 1 is a polyisobutylene-based sealing material comprising a component (a), a component (b) and a component (c).
The sealing material 2 was prepared by adding process oil in an amount that causes a slight decrease in viscosity in order to improve the properties generally performed in addition to the components of the sealing material 1. As a material for reducing the viscosity, a silane agent having a low viscosity is also effective, has reactivity, and can improve adhesion.
The sealing material 3 was prepared by adding fumed silica, which is a thixotropic agent, for improving mechanical properties as is generally done in addition to the components of the sealing material 1. If the addition amount is increased, the mechanical properties are improved, but the viscosity increases and the flow does not flow, so a small amount is added.
The encapsulant 4 was prepared by adding a large amount of fumed silica, which is a thixotropic agent, in addition to each component of the encapsulant 1 so that it does not flow even when applied on the lead.
As described above, a stabilizer such as a thiophene compound, an imino compound, a compound having an aliphatic unsaturated bond, an organic phosphorus compound, or an organic sulfur compound may be added to the sealing material. Further, other additives may be added.
Table 2 shows the sealing sites and basic characteristics of the sealing materials 1 to 4 used in Examples 1 to 4 and the sealing materials 5 to 7 used in Comparative Examples 1 to 3. In addition, each physical property value shown in Table 2 was measured by a conventional method.

Since the sealing materials 1 to 4 are soft (low hardness) and high in tensile elongation, when used as a sealing material, only a small amount of stress is generated due to a difference in linear expansion coefficient during heat curing. Since the elongation rate of the material due to the generated stress is high, no high stress is applied to the sealing material itself or other members, so that cracks and the like do not occur. In particular, it has strong resistance from the skeleton to water-based ink ejected from the recording head. That is, when each cured sample of the sealing materials 1 to 4 is immersed in an aqueous inkjet ink and subjected to a pressure cooker test (PCT) at 121 ° C. and 2 atm for 10 hours, Compared with materials 5-7, it is an extremely low value of about 1/5 to 1/20. Such an extremely low mass change rate also appears in electrical insulation (volume resistivity), and also shows a high value even when compared with the sealing materials 5 to 7 with almost no drop after ink immersion PCT. ing. The present invention finds that a material including a combination of the components (a) to (c) that imparts such characteristics is suitable for a sealing material such as an electrical connection portion and wiring in a liquid discharge head. It was made.
In addition, the sealing material 7 was prepared by adding fumed silica as a thixotropic agent so that the sealing material 4 did not flow even when applied on the lead.
As shown in FIG. 1 (c) and FIG. 2 (a), the electrical connection portions to which the leads were connected were sealed using the sealing materials 1 to 7 in the combinations shown in Table 2. . First, application | coating was performed using each of the sealing materials 1-4 as shown in FIG.2 (b). At this time, since it cannot be applied directly to the lower portion of the lead 6 by a dispenser because of space, it was applied to a region next to the lead portion and a sealing material was poured into the lower portion of the lead.
Next, as shown in FIGS. 1A and 1C, a sealing material is applied to the lead upper region using each of the sealing materials 4 to 6, and the heat curing treatment at 110 ° C. for 2 hours is sealed. It performed on the whole material and formed the sealing part which consists of hardened | cured material of a sealing material.

(Evaluation 1 H / S evaluation)
The heat shock (H / S) test in which the sealing portion was immersed in the ink for the recording head 15 produced as described above and subjected to heat treatment at 0 ° C. for 1 hour and 100 ° C. for 1 hour was performed 200 cycles.
As shown in Table 3, Examples 1 to 4 (using the sealing materials 1 to 4 as the surrounding sealing material) and Comparative Example 2 (the sealing material 5 as the surrounding sealing material and the electrical connection portion sealing material) In the case of using the sealing material 7, no change in appearance was observed. In Comparative Example 1 (using the sealing material 5 as the peripheral sealing material and the sealing material 6 as the electrical connection portion sealing material), all boundaries of the peripheral sealing material, the electrical connection portion sealing material, and the recording element substrate A micro crack was generated on the sealing material side.
The results obtained from Evaluation 1 are shown in Table 3.
Even when the sealing materials 1 to 4 of Examples 1 to 4 were exposed to ink, the physical properties hardly changed and the elongation rate was high, so that they did not change.
In the sealing material of Comparative Example 1, cracks occurred in the sealing portion of the electrical connection portion. This is because the hardness (Shore hardness A) and CTE (thermal expansion coefficient) of the cured product of the encapsulant 6 in the upper lead region and the cured product of the encapsulant 5 in the lower lead region differ greatly. This is thought to be because the cured product was exposed to ink and the properties were lowered to reduce elongation. When electrical connection inspection was performed, in Comparative Example 1, a slight leak current was generated.
In Comparative Example 2, since both the surrounding sealing material and the electrical connection portion sealing material have low elasticity and the same CTE, it is considered that no cracks occurred.

(Evaluation 2 Paper jam evaluation)
An ink supply member was attached to the recording head 15 produced as described above and mounted on an ink jet printing apparatus, and a paper jam test was performed.
In the paper jam test, a recording head is mounted on an ink jet printing apparatus, and solid pattern ink jet recording is performed on one sheet of plain paper (Canon A4 version). At that time, the paper discharge surface of the printer is blocked to forcibly cause a paper jam. Then, the paper partially ejected from the paper ejection roller is forcibly removed while swinging left and right by hand. Repeat this operation 10 times.
The results obtained from Evaluation 2 are shown in Table 3.
As shown in Table 3, regarding Examples 1 to 4 and Comparative Example 1, no change in appearance was observed.
However, in Comparative Example 2, the sealing portion of the electrical connection portion was missing. This is probably because the cured product of the electrical connection portion sealing material used in Comparative Example 2 was soft, but the sealing portion rubbed with paper was torn because the elongation was small.

As shown in Table 3, Examples 1 to 4 and Comparative Example 1 were able to be printed without any problems after the paper jam test.
As described above, the sealing portion according to the present embodiment can withstand both severe evaluations 1 and 2, and the long-term reliability of the recording head is remarkably improved.
The thermosetting composition of the present invention suitable for the electrical connection portion of the recording head can be suitably used not only for sealing but also for various parts of the liquid ejection head. For example, it can be suitably used for adhesion of an electrical wiring member of a liquid ejection device.

DESCRIPTION OF SYMBOLS 1 Substrate 2 Discharge energy generating element 3 Discharge port 4 Flow path member 5 Electrical wiring member 6 Lead 7 Support member 8 Horizontal surrounding sealing portion 9 Supply port 10 Terminal 11 Recess 12 First sealing material (peripheral sealing material, lead Lower area sealing material)
13 2nd sealing material (electric connection part sealing material, lead top area sealing material)
14 Recording element substrate 15 Recording head

Claims (8)

A recording element substrate comprising: a discharge member that discharges liquid; a flow path member that has a flow path that supplies liquid to the discharge port; and a substrate that includes an discharge energy generating element that generates energy for discharging liquid from the discharge port. When,
An electrical wiring member for transmitting a signal for driving the ejection energy generating element;
An electrical connection for electrically connecting the recording element substrate and the electrical wiring member;
Have
A first sealing material that seals a lower region of the electrical connection portion; a second sealing material that seals an upper region of the electrical connection portion;
A liquid ejection head comprising:
The first sealing material is
(A) a polyisobutylene compound having at least two alkenyl groups in one molecule;
(B) a compound having at least two hydrosilyl groups in one molecule;
(C) a hydrosilylation catalyst , and
(D) Ri sealing material A der curable contain plasticizers <br/>,
The second sealing material is
(A) a polyisobutylene compound having at least two alkenyl groups in one molecule;
(B) a compound having at least two hydrosilyl groups in one molecule;
(C) a hydrosilylation catalyst, and
(E) thixotropic agent
A curable encapsulant B containing, and
(I) an epoxy resin, a glycidyl ester resin, a glycidyl amine resin, a silicone-modified product thereof, a polybutadiene-modified product, a urethane-modified product, and a main agent selected from those obtained by polyfunctionalizing these,
(ii) a curing agent, and
(iii) Filler
A liquid discharge head characterized by being any one of sealing materials C containing The liquid discharge head according to claim 1 , wherein the first sealing material is a peripheral sealing material that seals the periphery of the recording element substrate. 3. The liquid ejection head according to claim 1, wherein the epoxy resin is selected from a bisphenol type epoxy resin, a bromine-containing epoxy resin, a phenol or cresol type epoxy resin, a cyclic aliphatic epoxy resin, and a heterocyclic epoxy resin . The liquid ejection head according to claim 1, wherein the thixotropic agent of the sealing material B is fumed silica. A recording element substrate comprising: a discharge member that discharges liquid; a flow path member that has a flow path that supplies liquid to the discharge port; and a substrate that includes an discharge energy generating element that generates energy for discharging liquid from the discharge port. When,
An electrical wiring member for transmitting a signal for driving the ejection energy generating element;
An electrical connection for electrically connecting the recording element substrate and the electrical wiring member;
A method of manufacturing a liquid discharge head having
The sealing position of the electrical connection portion is a lower region and an upper region of the electrical connection portion,
Filling a lower region of the electrical connection portion with a first sealing material;
A step of laminating a second sealing material for sealing the upper region of the electrical connection portion on the first sealing material filled in the lower region of the electrical connection portion so as to cover the electrical connection portion. When,
Curing the first sealing material;
Curing the second sealing material;
Have
The first sealing material is
(A) a polyisobutylene compound having at least two alkenyl groups in one molecule;
(B) a compound having at least two hydrosilyl groups in one molecule;
(C) a hydrosilylation catalyst , and
(D) Ri sealing material A der curable contain plasticizers <br/>,
The second sealing material is
(A) a polyisobutylene compound having at least two alkenyl groups in one molecule;
(B) a compound having at least two hydrosilyl groups in one molecule;
(C) a hydrosilylation catalyst, and
(E) thixotropic agent
A curable encapsulant B containing, and
(I) an epoxy resin, a glycidyl ester resin, a glycidyl amine resin, a silicone-modified product thereof, a polybutadiene-modified product, a urethane-modified product, and a main agent selected from those obtained by polyfunctionalizing these,
(ii) a curing agent, and
(iii) Filler
A method for manufacturing a liquid discharge head, which is any one of sealing materials C containing : Filling the lower region of the electrical connecting portion with the first sealing material is a surrounding sealing material that seals the periphery of the recording element substrate, and the recording element substrate The method for manufacturing a liquid discharge head according to claim 5 , wherein the method is performed by filling the first sealing material into the periphery. The liquid ejection head according to claim 5 or 6, wherein the epoxy resin is selected from a bisphenol type epoxy resin, a bromine-containing epoxy resin, a phenol or cresol type epoxy resin, a cycloaliphatic epoxy resin, and a heterocyclic epoxy resin. Method. The method of manufacturing a liquid discharge head according to claim 5, wherein the thixotropic agent of the sealing material B is fumed silica.

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