Patent Description:
<CIT> describes a droplet discharge head that pressurizes and supplies a discharge liquid to a cavity communicating with a nozzle, can cause a pin to close the nozzle, can cause an actuator to separate the pin from the nozzle and bring the pin into contact with the nozzle, and causes a control device to control the actuator, so that the pressurized and supplied discharge liquid is discharged as droplets from the nozzle only while the pin is separated from the nozzle. <CIT> discloses the use of a heat transfer layer in a liquid discharge head that has a needle valve.

A problem of the present embodiment is that a driver itself is displaced due to the heat generation of the driver, and a target discharge state cannot be maintained.

In an aspect of the present disclosure, a liquid discharge head includes: a housing; a nozzle plate attached to the housing, the nozzle plate having a nozzle from which a liquid is to be discharged; a valve in the housing, the valve configured to move in an opening and closing direction and openably close the nozzle; a driver having one end coupled to the valve in the opening and closing direction, the driver configured to drive the valve; and a fixing member fixed to the housing and coupled to another end of the driver in the opening and closing direction. The driver has a first linear expansion coefficient, each of the valve and the fixing member has a second linear expansion coefficient, the first linear expansion coefficient and the second linear expansion coefficient are reversed in positivity and negativity, and the driver is coupled to each of the valve and the fixing member via a heat transfer layer.

In another aspect of the present disclosure, a liquid discharge head includes: a housing; a nozzle plate attached to the housing, the nozzle plate having a nozzle from which a liquid is to be discharged; a valve in the housing, the valve configured to move in an opening and closing direction and openably close the nozzle; a driver having one end coupled to the valve in the opening and closing direction, the driver configured to drive the valve; a fixing member fixed to the housing and coupled to another end of the driver in the opening and closing direction; and an adjuster between the fixing member and said another end of the driver. The driver has a first linear expansion coefficient, each of the valve, the adjuster, and the fixing member has a second linear expansion coefficient, and the first linear expansion coefficient and the second linear expansion coefficient are reversed in positivity and negativity.

According to the present embodiment, it is possible to suppress the displacement of a driver itself due to the heat generation of the driver and maintain a target discharge state.

As used herein, the term "couple" means to join, connect, attach, adhere, affix, or bond, whether directly or indirectly, and whether permanently or temporarily.

Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

The configuration of a liquid discharge head according to an embodiment will be described with reference to <FIG> are explanatory views illustrating the configuration of a liquid discharge head according to a first embodiment of the present embodiment. <FIG> is a schematic cross-sectional view of a liquid discharge head illustrating a state where a nozzle is closed, and <FIG> is a schematic cross-sectional view of the liquid discharge head illustrating a state where the nozzle is opened.

A liquid discharge head <NUM> (thereinafter, referred to as a head) includes a housing <NUM> and a nozzle plate <NUM> attached to one end portion of the housing <NUM>.

The housing <NUM> includes multiple divided sub-housings, and in the present embodiment, the housing <NUM> includes three sub-housings, that is, a first housing 110a, a second housing 110b, and a third housing 110c.

A nozzle plate <NUM> is attached to a lower end portion of the third housing 110c, and a nozzle <NUM> that discharges a liquid is formed on the nozzle plate <NUM>. The third housing 110c includes a liquid inlet <NUM> for feeding the liquid into the head, a liquid chamber <NUM> for temporarily storing the liquid fed from the liquid inlet <NUM>, and a liquid outlet <NUM> for feeding the liquid out of the head.

The second housing 110b is joined to the end portion of the third housing 110c on a side opposite to a side where the nozzle plate <NUM> is attached. The second housing 110b includes a bearing <NUM> that supports a needle valve <NUM> described later so as to be movable in the opening and closing direction of the nozzle <NUM>.

The first housing 110a is joined to an end portion of the second housing 110b on a side opposite to a joint side with the third housing 110c. The first housing 110a stores an actuator <NUM>. The configuration of the actuator <NUM> is not particularly limited as long as it can be displaced in a vertical direction in <FIG> by applying a voltage, but in the present embodiment, a piezoelectric element that expands and contracts by voltage application is used as the actuator <NUM>. The needle valve <NUM> and a fixing member <NUM> are provided at both end portions in the displacement direction (expansion/contraction direction) of the actuator <NUM> via an elastic member <NUM>.

The elastic member <NUM> includes a frame portion 133a formed so as to surround the actuator <NUM>, a spring portion 133b provided in a part of the frame portion 133a, and contact portions 133c and 133d that contact both ends of the actuator <NUM>. The actuator <NUM> is sandwiched between the contact portion 133c and the contact portion 133d by the contraction force of the spring portion 133b, and is supported by the elastic member <NUM>.

One end of the needle valve <NUM> is joined to a lower portion (opposite side of the contact portion 133d) of the frame portion 133a of the elastic member <NUM>, and the other end of the needle valve <NUM> is provided so as to be able to contact the nozzle <NUM> in the nozzle plate <NUM>.

The fixing member <NUM> contacts an upper portion (opposite side of the contact portion 133c) of the frame portion 133a of the elastic member <NUM>, and the fixing member <NUM> is secured to the first housing 110a by a fixing portion 118a. That is, the fixing member <NUM> forms a securing point such that the elastic member <NUM> cannot move upward by the displacement (expansion and contraction) of the actuator <NUM>.

As described above, the needle valve <NUM> and the actuator <NUM> are coaxially disposed via the elastic member <NUM>, that is, disposed in series in a liquid discharge direction. Note that the elastic member <NUM> is not necessarily formed as an integrated member, and for example, the elastic member <NUM> may be configured by connecting the frame portion 133a and the spring portion 133b prepared as separate members. It is preferable to use a low expansion metal such as stainless steel or Invar for the elastic member <NUM>.

A heat transfer layer <NUM> is provided between the actuator <NUM> and the contact portion 133d of the elastic member <NUM> and between the actuator <NUM> and the contact portion 133c of the elastic member <NUM>. The configuration of the heat transfer layer <NUM> is not particularly limited as long as it can efficiently dissipate the heat of the actuator <NUM>. For example, the heat transfer layer <NUM> is formed of a sheet material or a film material made of heat dissipating silicone, and is also formed by applying grease-like heat dissipating silicone obtained by blending a powder having high thermal conductivity with silicone oil.

In the first embodiment, the elastic member <NUM> may not be provided. In this case, the heat transfer layer <NUM> is provided between the actuator <NUM> and the needle valve <NUM> and between the actuator <NUM> and the fixing member <NUM>.

Here, the needle valve <NUM> is an example of a "valve", and the actuator <NUM> is an example of a "driver".

In the above configuration, when a predetermined drive voltage is applied to the actuator <NUM>, the actuator <NUM> contracts by ΔL from a position illustrated in <FIG> and changes to a position illustrated in <FIG>. As a result, the elastic member <NUM> also deforms in a contraction direction, and the needle valve <NUM> attached to the elastic member <NUM> moves in a direction forming a gap G with respect to the nozzle plate <NUM>. By the movement of the needle valve <NUM>, the nozzle <NUM> is opened, and a fluid pressurized and supplied to the liquid chamber <NUM> is discharged as a droplet D from the nozzle <NUM>.

Next, distance variation due to the thermal deformation of the liquid discharge head will be described with reference to <FIG> is an explanatory view of distance variation due to the thermal deformation of the liquid discharge head.

The actuator <NUM> generates heat in accordance with the liquid discharge operation, and the heat causes the thermal deformation of the components of the head <NUM>. When the components of the head <NUM> are thermally deformed and the needle valve <NUM> does not correctly contact the nozzle plate <NUM>, a gap is generated between the needle valve <NUM> and the nozzle plate <NUM>. This gap connects the liquid chamber <NUM> and the nozzle <NUM>, causing a situation in which the liquid is constantly discharged from the nozzle <NUM>.

In order to prevent such a situation, in the head of the first embodiment, the difference between the thermal fluctuation of the housing <NUM> and the thermal fluctuation of the stored member (needle valve <NUM>, actuator <NUM>, fixing member <NUM>) stored in the housing <NUM> is configured to be close to <NUM>. Strictly speaking, although thermal deformation also occurs in the elastic member <NUM>, the thickness of the elastic member <NUM> is small in the longitudinal direction (liquid discharge direction), and the deformation amount is at a level that causes no disadvantage. Therefore, it is ignored here.

The thermal fluctuation of the housing <NUM> is, that is, distance fluctuation from the fixing portion 118a in the housing <NUM> to the inside of the nozzle plate <NUM>, and is the fluctuation of the length of X + Y + Z in <FIG>. Note that X is a length in the liquid discharge direction of the first housing <NUM>10a, Yis a length in the liquid discharge direction of the second housing 110b, and Z is a length in the liquid discharge direction of the third housing 110c.

The thermal fluctuation of the stored member stored in the housing <NUM> is, that is, distance fluctuation from the fixing portion 118a to the needle valve <NUM>, and is the fluctuation of the length of A + M + B in <FIG>. A is the length of the fixing member <NUM> in the liquid discharge direction, M is the length of the actuator <NUM> in the liquid discharge direction, and B is the length of the needle valve <NUM> in the liquid discharge direction.

In the first embodiment, only M (actuator <NUM>) has a negative thermal expansion (contraction by heat) characteristic, so that materials other than M having a positive thermal expansion (expansion by heat) characteristic are used. That is, the fixing member <NUM> and the needle valve <NUM> are made of a material whose lengths A and B increase as the temperature rises, and a material having a reverse sign relationship with respect to the linear expansion coefficient of the actuator <NUM> is used. As a result, the amount by which the actuator <NUM> contracts due to the temperature rise of the actuator <NUM> and M decreases can be offset by the amount by which A (fixing member <NUM>) and B (needle valve <NUM>) increase. As a result, it is possible to prevent constant discharge and an increase in discharge caused by the gap between the needle valve <NUM> and the nozzle plate <NUM> due to the temperature rise of long-time drive.

At least one of a first housing 110a, a second housing 110b, and a third housing 110c may be made of a material having a low linear expansion coefficient, such as low expansion metal. Examples of the low expansion metal include Invar, which is an alloy of iron and nickel. As a result, it is possible to suppress distance variation (variation of X + Y + Z) that is received by a housing <NUM> from the heat generation of the actuator <NUM>.

The second housing 110b sandwiched between the first housing 110a and the third housing 110c may have heat shielding properties. The heat shielding properties in the present embodiment mean a property of reflecting heat from the actuator <NUM>. The heat shielding properties may be obtained by forming the second housing 110b itself with a heat shielding material, or by providing a sheet having a surface to which an aluminum foil, aluminum vapor deposition, or an aluminum film or the like is applied, on a surface of the second housing 110b requiring heat shielding. As a result, when the housing <NUM> is divided into multiple sub-housings, the processing accuracy of the entire housing <NUM> can be improved, and the distance variation (variation of X + Y + Z) of the housing <NUM> can be suppressed by sandwiching the housing having heat shielding properties. That is, since the second housing 110b bounces the heat, the heat is less likely to be transferred to the third housing 110c, and the fluctuation of Z can be made substantially <NUM>.

Since the nozzle <NUM> on the nozzle plate <NUM> is required to be processed with high accuracy, it is desirable to process the nozzle plate <NUM> alone. In this case, it is necessary to chemically adhere the nozzle plate <NUM> on which the nozzle <NUM> is formed to the third housing 110c later. In the configuration in which the nozzle plate <NUM> is adhered to the third housing 110c later as described above, the third housing 110c and the nozzle plate <NUM> are preferably formed of the same material. As a result, it is possible to suppress the positional displacement of the nozzle plate <NUM> with respect to the third housing 110c due to thermal fluctuation.

As described above, according to the first embodiment, in the head <NUM> including the actuator <NUM> having a negative thermal expansion characteristic and the members around the actuator having a positive thermal expansion characteristic, the thermal displacement of the contact portion between the nozzle <NUM> provided on the housing <NUM> side and the needle valve <NUM> connected to the actuator <NUM> can be brought close to <NUM>.

Although the configuration in which the actuator <NUM> has a negative thermal expansion characteristic (negative linear expansion coefficient) and the fixing member <NUM> and the needle valve <NUM> have a positive thermal expansion characteristic (positive linear expansion coefficient) has been described above, if the linear expansion coefficient of the actuator <NUM> and the linear expansion coefficients of the fixing member <NUM> and the needle valve <NUM> have opposite signs, it is possible to obtain a similar effect of bringing the thermal displacement of the contact portion between the nozzle <NUM> and the needle valve <NUM> close to <NUM>. For example, the actuator <NUM> may be configured to have a positive thermal expansion characteristic (positive linear expansion coefficient), and the fixing member <NUM> and the needle valve <NUM> may be configured to have a negative thermal expansion characteristic (negative linear expansion coefficient).

As described above, the present embodiment includes the housing <NUM>, the nozzle plate <NUM> attached to the housing <NUM> and formed with the nozzle <NUM> that discharges a liquid, the needle valve <NUM> that is stored in the housing <NUM> and opens and closes the nozzle <NUM>, the actuator <NUM> that is provided at the end portion in the opening and closing direction of the needle valve <NUM> and drives the needle valve <NUM>, and the fixing member <NUM> that is provided at the end portion in the driving direction of the actuator <NUM> and is secured to the housing <NUM>. The linear expansion coefficient of the actuator <NUM> and the linear expansion coefficients of the needle valve <NUM> and the fixing member <NUM> have a reverse sign relationship, and the actuator <NUM> and the needle valve <NUM>, and the actuator <NUM> and the fixing member <NUM> are connected via the heat transfer layer <NUM>.

As a result, the fluctuation of the member due to the heat generation of the actuator <NUM> can be suppressed, and the target discharge state can be maintained.

As described above, the housing <NUM> is divided into multiple (three in the present embodiment) sub-housings, and at least one of the multiple divided sub-housings 110a, 110b, and 110c is made of Invar.

As a result, it is possible to suppress distance variation that is received by the housing <NUM> from the heat generation of the actuator <NUM>.

As described above, the housing <NUM> is divided into three or more sub-housings, and the intermediate sub-housing (second housing 110b) among the multiple sub-housings 110a, 110b, and 110c has heat shielding properties.

As a result, the second housing 110b bounces heat and makes it difficult to transmit the heat to the third housing 110c, so that the variation of the third housing 110c can be made substantially <NUM>.

As described above, the housing <NUM> and the nozzle plate <NUM> are chemically adhered, and the housing <NUM> and the nozzle plate <NUM> are made of the same material. In particular, the third housing 110c to which the nozzle plate <NUM> is adhered and the nozzle plate <NUM> are made of the same material.

As a result, it is possible to suppress the positional displacement of the nozzle plate <NUM> with respect to the third housing 110c due to thermal fluctuation.

<FIG> is an explanatory view illustrating the configuration of a liquid discharge head according to a second embodiment of the present embodiment.

The second embodiment is different from the first embodiment in that an adjuster <NUM> is provided at an end portion in an expansion/contraction direction which is the driving direction of an actuator <NUM>. The actuator <NUM> and the adjuster <NUM> are coaxially disposed, that is, in series in a liquid discharge direction. The adjuster <NUM> suppresses the thermal contraction of M due to the heat generation of the actuator <NUM> by using a material having a linear expansion coefficient in a reverse sign relationship with the actuator <NUM>. As a result, the variation in the entire length of A + M + B can be reduced.

As described above, according to the second embodiment, in the head <NUM> including the actuator <NUM> having a negative thermal expansion characteristic and the members around the actuator having a positive thermal expansion characteristic, the thermal displacement of the contact portion between the nozzle <NUM> provided on the housing <NUM> side and the needle valve <NUM> connected to the actuator <NUM> can be brought close to <NUM>.

Although the configuration in which the actuator <NUM> has a negative thermal expansion characteristic (negative linear expansion coefficient) and the adjuster <NUM> has a positive thermal expansion characteristic (positive linear expansion coefficient) has been described above, if the linear expansion coefficient of the actuator <NUM> and the linear expansion coefficient of the adjuster <NUM> have opposite signs, it is possible to obtain a similar effect of bringing the thermal displacement of the contact portion between the nozzle <NUM> and the needle valve <NUM> close to <NUM>. For example, the actuator <NUM> may be configured to have a positive thermal expansion characteristic (positive linear expansion coefficient), and the adjuster <NUM> may be configured to have a negative thermal expansion characteristic (negative linear expansion coefficient).

As described above, the present embodiment includes the housing <NUM>, the nozzle plate <NUM> attached to the housing <NUM> and formed with the nozzle <NUM> that discharges a liquid, the needle valve <NUM> that is stored in the housing <NUM> and opens and closes the nozzle <NUM>, the actuator <NUM> that is provided at the end portion in the opening and closing direction of the needle valve <NUM> and drives the needle valve <NUM>, the adjuster <NUM> attached to the end portion in the driving direction of the actuator <NUM>, and the fixing member <NUM> that is provided at the end portion of the adjuster <NUM> and secured to the housing <NUM>. The linear expansion coefficient of the actuator <NUM> and the linear expansion coefficients of the needle valve <NUM>, the adjuster <NUM>, and the fixing member <NUM> have a reverse sign relationship.

<FIG> are explanatory views illustrating the configuration of a liquid discharge head according to a third embodiment of the present embodiment. <FIG> is a schematic cross-sectional view of the liquid discharge head, and <FIG> is an enlarged view of a joint portion between an actuator and an adjuster.

The third embodiment is different from the second embodiment in that an adjuster <NUM> provided at the end portion of an actuator <NUM> is joined so as to cover the end portion of the actuator <NUM>. In the joining of the actuator <NUM> and the adjuster <NUM>, as illustrated in <FIG>, a joint portion 138a is preferably only a surface intersecting with an expansion/contraction direction so as not to hinder the expansion/contraction operation of the actuator <NUM>.

A heat transfer layer <NUM> is provided in a gap between the actuator <NUM> and the adjuster <NUM> excluding the joint portion 138a. The configuration of the heat transfer layer <NUM> is not particularly limited as long as it can efficiently dissipate the heat of the actuator <NUM>. For example, the heat transfer layer <NUM> is formed of a sheet material or a film material made of heat dissipating silicone, and is also formed by applying grease-like heat dissipating silicone obtained by blending a powder having high thermal conductivity with silicone oil. As a result, the heat of the actuator <NUM> is more easily transferred to the adjuster <NUM>, and the thermal contraction of M due to the heat generation of the actuator <NUM> can be suppressed.

As described above, according to the third embodiment, in the head <NUM> including the actuator <NUM> having a negative thermal expansion characteristic and the members around the actuator having a positive thermal expansion characteristic, the thermal displacement of the contact portion between the nozzle <NUM> provided on the housing <NUM> side and the needle valve <NUM> connected to the actuator <NUM> can be brought close to <NUM>.

As described above, the actuator <NUM> and the adjuster <NUM> are connected via the heat transfer layer <NUM>.

As a result, the heat of the actuator <NUM> is more easily transferred to the adjuster <NUM>, and the thermal contraction due to the heat generation of the actuator <NUM> can be suppressed.

Next, an application example will be described with reference to <FIG> is an explanatory view illustrating the application example.

As illustrated in <FIG>, a head module <NUM> includes multiple (eight in this example) heads <NUM> in a housing <NUM>. The housing <NUM> includes a supply port <NUM> for supplying a liquid into the housing <NUM>, a supply path <NUM> connecting the supply port <NUM> and a liquid inlet <NUM>, and a liquid outlet <NUM> provided on the opposite side of the liquid inlet <NUM> across a liquid chamber <NUM>. The housing <NUM> includes a collection port <NUM> for collecting the liquid in the housing <NUM>, and a collection path <NUM> connecting the collection port <NUM> and the liquid outlet <NUM>.

For the multiple heads <NUM>, <FIG> illustrates the head illustrated in the above-described first embodiment, but it is of course possible to implement the head described in the second embodiment or the third embodiment. The basic configuration of the head <NUM> is similar to that described in <FIG> and <FIG> and <FIG>, and in <FIG>, corresponding elements are denoted by reference numerals in the <NUM> series.

In the present application example, the eight heads <NUM> are provided such that respective nozzles <NUM> are arranged at substantially equal intervals in one direction (left-right direction in <FIG>). Each of the heads <NUM> is provided to extend in the vertical direction so as to discharge the liquid downward from the nozzles <NUM> in the lower part of <FIG>.

The liquid chamber <NUM> of each head <NUM> is provided to penetrate so that the liquid flows from one side (left side in <FIG>) to the other side (right side in <FIG>) in the arrangement direction of the eight heads <NUM>.

Next, an application example of the head module <NUM> described in <FIG> will be described with reference to <FIG> and <FIG>. <FIG> is an overall perspective view illustrating an example of a carriage, and <FIG> is an overall perspective view illustrating an example of a liquid discharge apparatus on which the carriage of <FIG> is mounted. <FIG> illustrates a carriage <NUM> mounted on a liquid discharge apparatus <NUM> illustrated in <FIG> as viewed from a liquid discharge object <NUM> side.

The carriage <NUM> includes a head holder <NUM>. The carriage <NUM> is movable in a Z direction (positive side and negative side) along a Z-axis rail <NUM> by power from a first Z-direction driving unit <NUM> described later.

The head holder <NUM> is movable in the Z-direction (positive side and negative side) with respect to the carriage <NUM> by power from a second Z-direction driving unit <NUM> described later. The head holder <NUM> includes a head securing plate 80a to which the head module <NUM> is attached.

In the present application example, a configuration in which six head modules <NUM> described in <FIG> are attached to the head securing plate 80a is exemplified, and the six head modules <NUM> are provided side by side in a stacked manner.

Each of the head modules <NUM> includes multiple nozzles <NUM>. Note that the type and number of colors of inks used in the head modules <NUM> may be different for each of the head modules, or all the inks may have the same color. For example, when the liquid discharge apparatus <NUM> is a coating apparatus using a single color, the inks used in the six head modules <NUM> may have the same color. The number of the head modules <NUM> is not limited to <NUM>. The number may be more than <NUM> or less than <NUM>.

The head module <NUM> is secured to the head securing plate 80a in a state where a nozzle row (a row formed by eight nozzles <NUM>) of each head module intersects with a horizontal plane (X-Z plane) and the arrangement direction of the multiple nozzles <NUM> is inclined with respect to an X axis. In this state, the nozzle <NUM> discharges the liquid in a direction (positive side in the Z direction) intersecting with the gravity direction.

A printing apparatus <NUM> as an example of the liquid discharge apparatus illustrated in <FIG> is installed to face the liquid discharge object <NUM>. The printing apparatus <NUM> includes an X-axis rail <NUM>, a Y-axis rail <NUM> intersecting with the X-axis rail <NUM>, and a Z-axis rail <NUM> intersecting with the X-axis rail <NUM> and the Y-axis rail <NUM>.

The Y-axis rail <NUM> holds the X-axis rail <NUM> such that the X-axis rail <NUM> is movable in a Y direction (positive side and negative side). The X-axis rail <NUM> holds the Z-axis rail <NUM> such that the Z-axis rail <NUM> is movable in an X direction (positive side and negative side). The Z-axis rail <NUM> holds the carriage <NUM> such that the carriage <NUM> is movable in the Z direction (positive side and negative side).

The printing apparatus <NUM> includes a first Z-direction driving unit <NUM> that causes the carriage <NUM> to move in the Z direction along the Z-axis rail <NUM>, and an X-direction driving unit <NUM> that causes the Z-axis rail <NUM> to move in the X direction along the X-axis rail <NUM>. The printing apparatus <NUM> includes a Y-direction driving unit <NUM> that causes the X-axis rail <NUM> to move in the Y direction along the Y-axis rail <NUM>. The printing apparatus <NUM> further includes a second Z-direction driving unit <NUM> that causes the head holder <NUM> to move in the Z direction with respect to the carriage <NUM>.

The printing apparatus <NUM> configured as described above discharges ink as an example of a liquid from the head module <NUM> (see <FIG>) provided in the head holder <NUM> to perform printing on the liquid discharge object <NUM> while causing the carriage <NUM> to move in the X direction, the Y direction, and the Z direction. The movement of the carriage <NUM> and the head holder <NUM> in the Z direction does not necessarily mean parallel to the Z direction, and may be oblique movement as long as the movement includes at least a component in the Z direction.

In <FIG>, the surface shape of the liquid discharge object <NUM> is a flat surface, but the surface shape of the liquid discharge object <NUM> may be a surface close to a vertical direction such as a vehicle body of a vehicle or a truck, or a body of an aircraft, a surface having a large radius of curvature, or a surface having some irregularities.

In the present embodiment, examples of the liquid include solutions, suspensions, and emulsions containing solvents such as water and organic solvents, colorants such as dyes and pigments, function-imparting materials such as polymerizable compounds, resins, and surfactants, biocompatible materials such as deoxyribonucleic acid (DNA), amino acids, proteins, and calcium, and edible materials such as natural pigments, and the like.

These can be used for, for example, inkjet inks, paint coating materials, surface treatment liquids, constituent elements of electronic elements and light emitting elements, liquids for forming electronic circuit resist patterns, and material liquids for three-dimensional modeling, and the like.

Claim 1:
A liquid discharge head (<NUM>) comprising:
a housing (<NUM>);
a nozzle plate (<NUM>) attached to the housing (<NUM>), the nozzle plate (<NUM>) having a nozzle (<NUM>) from which a liquid is to be discharged;
a valve (<NUM>) in the housing (<NUM>), the valve (<NUM>) configured to move in an opening and closing direction and openably close the nozzle (<NUM>);
a driver (<NUM>) having one end coupled to the valve (<NUM>) in the opening and closing direction, the driver (<NUM>) configured to drive the valve (<NUM>); and
a fixing member (<NUM>) fixed to the housing (<NUM>) and coupled to another end of the driver (<NUM>) in the opening and closing direction,
wherein the driver (<NUM>) has a first linear expansion coefficient,
each of the valve (<NUM>) and the fixing member (<NUM>) has a second linear expansion coefficient,
the first linear expansion coefficient and the second linear expansion coefficient are reversed in positivity and negativity, and
the driver (<NUM>) is coupled to each of the valve (<NUM>) and the fixing member (<NUM>) via a heat transfer layer (<NUM>).