Liquid ejecting head, liquid ejecting device and liquid ejecting method

A liquid ejecting method includes providing a substrate having a heat generating surface for generating heat for generating a bubble in liquid; providing a movable member having a free end; providing an ejection outlet for ejecting the liquid using the generation of the bubble, the ejection outlet being opposed to the substrate with the movable member interposed therebetween; disposing the free end of the movable member at a downstream side with respect to a direction of flow of the liquid to the ejection outlet; and wherein the bubble displaces the free end of the movable member, and grows toward the ejection outlet to eject the liquid.

FIELD OF THE INVENTION AND RELATED ART 
The present invention relates to a liquid ejecting head for ejecting 
desired liquid using generation of a bubble by applying thermal energy to 
the liquid, a head cartridge using the liquid ejecting head, a liquid 
ejecting device using the same, a manufacturing method for the liquid 
ejecting head, a liquid ejecting method, a recording method, and a print 
provided using the liquid ejecting method. It further relates to an ink 
jet head kit containing the liquid ejection head. 
More particularly, it relates to a liquid ejecting head having a movable 
member movable by generation of a bubble, and a head cartridge using the 
liquid ejecting head, and liquid ejecting device using the same. It 
further relates to a liquid ejecting method and recording method for 
ejection the liquid by moving the movable member using the generation of 
the bubble. 
The present invention is applicable to equipment such as a printer, a 
copying machine, a facsimile machine having a communication system, a word 
processor having a printer portion or the like, and an industrial 
recording device combined with various processing device or processing 
devices, in which the recording is effected on a recording material such 
as paper, thread, fiber, textile, leather, metal, plastic resin material, 
glass, wood, ceramic and so on. 
In this specification, "recording" means not only forming an image of 
letter, figure or the like having specific meanings, but also includes 
forming an image of a pattern not having a specific meaning. 
An ink jet recording method of so-called bubble jet type is known in which 
an instantaneous state change resulting in an instantaneous volume change 
(bubble generation) is caused by application of energy such as heat to the 
ink, so as to eject the ink through the ejection outlet by the force 
resulted from the state change by which the ink is ejected to and 
deposited on the recording material to form an image formation. As 
disclosed in U.S. Pat. No. 4,723,129, a recording device using the bubble 
jet recording method comprises an ejection outlet for ejecting the ink, an 
ink flow path in fluid communication with the ejection outlet, and an 
electrothermal transducer as energy generating means disposed in the ink 
flow path. 
With such a recording method is advantageous in that, a high quality image, 
can be recorded at high speed and with low noise, and a plurality of such 
ejection outlets can be posited at high density, and therefore, small size 
recording apparatus capable of providing a high resolution can be 
provided, and color images can be easily formed. Therefore, the bubble jet 
recording method is now widely used in printers, copying machines, 
facsimile machines or another office equipment, and for industrial systems 
such as textile printing device or the like. 
With the increase of the wide needs for the bubble jet technique, various 
demands are imposed thereon, recently. 
For example, an improvement in energy use efficiency is demanded. To meet 
the demand, the optimization of the heat generating element such as 
adjustment of the thickness of the protecting film is investigated. This 
method is effective in that a propagation efficiency of the generated heat 
to the liquid is improved. 
In order to provide high image quality images, driving conditions have been 
proposed by which the ink ejection speed is increased, and/or the bubble 
generation is stabilized to accomplish better ink ejection. As another 
example, from the standpoint of increasing the recording speed, flow 
passage configuration improvements have been proposed by which the speed 
of liquid filling (refilling) into the liquid flow path is increased. 
Japanese Laid Open Patent Application No. SHO-63-199972 propose flow 
passage structures as disclosed in FIG. 1, (a) and (b), for example. 
The liquid path or passage structure of a manufacturing method therefor are 
proposed from the standpoint of the back wave toward the liquid chamber. 
This back wave is considered as energy loss since it does not contribute 
to the liquid ejection. It proposes a valve 10 disposed upstream of the 
heat generating element 2 with respect to the direction of general flow of 
the liquid, and is mounted on the ceiling of the passage. It takes an 
initial position wherein it extends along the ceiling. Upon bubble 
generation, it takes the position wherein it extends downwardly, thus 
suppressing a part of the back wave by the valve 10. When th valve is 
generated in the path 3, the suppression of the back wave is not 
practically significant. The back wave is not directly contributable to 
the ejection of the liquid. Upon the back wave occurs in the path, the 
pressure for directly ejecting the liquid already makes the liquid 
ejectable from the passage. 
On the other hand, in the bubble jet recording method, the heating is 
repeated with the heat generating element contacted with the ink, and 
therefore, a burnt material is deposited on the surface of the heat 
generating element due to kogation of the ink. However, the amount of the 
deposition may be large depending on the materials of the ink if this 
occurs, the ink ejection becomes unstable. Additionally, even when the 
liquid to be ejected is the one easily deteriorated by heat or even when 
the liquid is the one with which the bubble generation is not sufficient, 
the liquid is desired to be ejected in good order without property change. 
Japanese Laid Open Patent Application No. SHO-61-69467, Japanese Laid Open 
Patent Application No. SHO-55-81172 and U.S. Pat. No. 4,480,259 disclose 
that different liquids are used for the liquid generating the bubble by 
the heat (bubble generating liquid) and for the liquid to be ejected 
(ejection liquid). In these publications, the ink as the ejection liquid 
and the bubble generation liquid are completely separated by a flexible 
film of silicone rubber or the like so as to prevent direct contact of the 
ejection liquid to the heat generating element while propagating the 
pressure resulting from the bubble generation of the bubble generation 
liquid to the ejection liquid by the deformation of the flexible film. The 
prevention of the deposition of the material on the surface of the heat 
generating element and the increase of the selection latitude of the 
ejection liquid are accomplished, by such a structure. 
However, with this structure in which the ejection liquid and the bubble 
generation liquid are completely separated, the pressure by the bubble 
generation is progated to the ejection liquid through the 
expansion-contraction deformation of the flexible film, and therefore, the 
pressure is absorbed by the flexible film to a quite high degree. In 
addition, the deformation of the flexible film is not so large, and 
therefore, the energy use efficiency and the ejection force are 
deteriorated although the same effect is provided by the provision between 
the ejection liquid and the bubble generation liquid. 
SUMMARY OF THE INVENTION 
Accordingly, it is a principal object of the present invention to provide a 
liquid ejection principle with which the generated bubble is controlled in 
a novel manner. 
It is another object of the present invention to provide a liquid ejecting 
method, liquid ejecting head and so on wherein heat accumulation in the 
liquid on the heat generating element is significantly reduced, and the 
residual bubble on the heat generating element is reduced, while improving 
the ejection and the ejection pressure. 
It is a further object of the present invention to provide a liquid 
ejecting head and so on wherein inertia force in a direction against 
liquid supply direction due to back wave is suppressed, and 
simultaneously, a degree of retraction of a meniscus is reduction by a 
valve function of a movable member by which the refilling frequency is 
increased, thus permitting high speed printing. 
It is a further object of the present invention to provide a liquid 
ejecting head and so on wherein deposition of residual material on the 
heat generating element is reduced, and the range of the usable liquid is 
widened, and in addition, the ejection efficiency and the ejection force 
are significantly increased. 
It is a further object of the present invention to provide a liquid 
ejecting method, a liquid ejecting head and so on, wherein the choice of 
the liquid to be ejected is made greater. 
It is a further object of the present invention to provide a manufacturing 
method for a liquid ejecting head with which such a liquid ejecting head 
is easily manufactured. 
It is a further object of the present invention to provide a liquid 
ejecting head, a printing apparatus and so on which can be easily 
manufactured because a liquid introduction path for supplying a plurality 
of liquids are constituted with a small number of parts it is an 
additional object to provide a downsized liquid ejecting head and device. 
It is a further object of the present invention to provide a good print of 
an image using an above-described ejection method. 
It is a further object of the present invention to provide a head kit for 
permitting easy refuse of the liquid ejecting head. 
According to an aspect of the present invention, there is provided a liquid 
ejecting method, comprising: providing a substrate having a heat 
generating surface for generating heat for generating a bubble in liquid; 
providing a movable member having a free end; providing an ejection outlet 
for ejecting the liquid using the generation of the bubble, the ejection 
outlet being opposed to the substrate with the movable member interposed 
therebetween; disposing the free end of the movable member at a downstream 
side with respect to a direction of flow of the liquid to the ejection 
outlet; and wherein the bubble displaces the free end of the movable 
member, and grows toward the ejection outlet to eject the liquid. 
According to another aspect of the present invention, there is provided a 
liquid ejecting method, comprising: providing a heat generating surface 
for generating heat for generating a bubble in liquid; providing a movable 
member having a free end; providing an ejection outlet for ejecting the 
liquid using the generation of the bubble, the ejection outlet being 
opposed to the heat generating surface with the movable member interposed 
therebetween; disposing the free end of the movable member at a downstream 
side with respect to a direction of flow of the liquid to the ejection 
outlet; and wherein the bubble displaces the free end of the movable 
member, and grows toward the ejection outlet to eject the liquid. 
According to a further aspect of the present invention, there is provided a 
liquid ejection head comprising: a substrate having a heat generating 
surface for generating heat for generating a bubble in liquid; a movable 
member having a free end; an ejection outlet for ejecting the liquid using 
the generation of the bubble, the ejection outlet being opposed to the 
substrate with the movable member interposed therebetween; an opposing 
member cooperable with the movable member to direct the bubble toward the 
ejection outlet, wherein the opposing member opposes to such a side of the 
movable member as is near to the heat generating surface when the free end 
of the movable member is displaced by the bubble. 
According to a further aspect of the present invention, there is provided a 
liquid ejection head comprising: a heat generating surface for generating 
heat for generating a bubble in liquid; a movable member having a free 
end; an ejection outlet for ejecting the liquid using the generation of 
the bubble, the ejection outlet being opposed to the heat generating 
surface with the movable member interposed therebetween; an opposing 
member cooperable with the movable member to direct the bubble toward the 
ejection outlet, wherein the opposing member opposes to such a side of the 
movable member as is near to the heat generating surface when the free end 
of the movable member is displaced by the bubble. 
According to a further aspect of the present invention, there is provided a 
head cartridge comprising: a liquid ejection head including; a substrate 
having a heat generating surface for generating heat for generating a 
bubble in liquid; a movable member having a free end; an ejection outlet 
for ejecting the liquid using the generation of the bubble, the ejection 
outlet being opposed to the substrate with the movable member interposed 
therebetween; an opposing member cooperable with the movable member to 
direct the bubble toward the ejection outlet, wherein the opposing member 
opposes to such a side of the movable member as is near to the heat 
generating surface when the free end of the movable member is displaced by 
the bubble; and the head cartridge further comprising: a liquid containing 
portion for containing the liquid to be supplied to the liquid ejecting 
head. 
According to a further aspect of the present invention, there is provided a 
head cartridge comprising: a liquid ejection head including: a heat 
generating surface for generating heat for generating a bubble in liquid; 
a movable member having a free end; an ejection outlet for ejecting the 
liquid using the generation of the bubble, the ejection outlet being 
opposed to the heat generating surface with the movable member interposed 
therebetween; an opposing member cooperable with the movable member to 
direct the bubble toward the ejection outlet, wherein the opposing member 
opposes to such a side of the movable member as is near to the heat 
generating surface when the free end of the movable member is displaced by 
the bubble; and the head cartridge further comprising: a liquid containing 
portion for containing the liquid to be supplied to the liquid ejecting 
head. 
According to a further aspect of the present invention, there is provided a 
liquid ejection apparatus comprising: a liquid ejection head including; a 
substrate having a heat generating surface for generating heat for 
generating a bubble in liquid; a movable member having a free end; an 
ejection outlet for ejecting the liquid using the generation of the 
bubble, the ejection outlet being opposed to the substrate with the 
movable member interposed therebetween; an opposing member cooperable with 
the movable member to direct the bubble toward the ejection outlet, 
wherein the opposing member opposes to such a side of the movable member 
as is near to the heat generating surface when the free end of the movable 
member is displaced by the bubble; and the apparatus further comprising: 
driving signal supply means for supplying a driving signal for ejecting 
the liquid. 
According to a further aspect of the present invention, there is provided a 
liquid ejection apparatus comprising: a liquid ejection head including; a 
substrate having a heat generating surface for generating heat for 
generating a bubble in liquid; a movable member having a free end; an 
ejection outlet for ejecting the liquid using the generation of the 
bubble, the ejection outlet being opposed to the substrate with the 
movable member interposed therebetween; an opposing member cooperable with 
the movable member to direct the bubble toward the ejection outlet, 
wherein the opposing member opposes to such a side of the movable member 
as is near to the heat generating surface when the free end of the movable 
member is displaced by the bubble; and transporting means for transporting 
a recording material for receiving the liquid ejected from the liquid 
ejecting head. 
According to a further aspect of the present invention, there is provided a 
liquid ejection apparatus comprising: a liquid ejection head including; a 
heat generating surface for generating heat for generating a bubble in 
liquid; a movable member having a free end; an ejection outlet for 
ejecting the liquid using the generation of the bubble, the ejection 
outlet being opposed to the heat generating surface with the movable 
member interposed therebetween; an opposing member cooperable with the 
movable member to direct the bubble toward the ejection outlet, wherein 
the opposing member opposes to such a side of the movable member as is 
near to the heat generating surface when the free end of the movable 
member is displaced by the bubble; and the apparatus further comprising: 
driving signal supply means for supplying a driving signal for ejecting 
the liquid. 
According to a further aspect of the present invention, there is provided a 
liquid ejection apparatus comprising: a liquid ejection head including; a 
heat generating surface for generating heat for generating a bubble in 
liquid; a movable member having a free end; an ejection outlet for 
ejecting the liquid using the generation of the bubble, the ejection 
outlet being opposed to the heat generating surface with the movable 
member interposed therebetween; an opposing member cooperable with the 
movable member to direct the bubble toward the ejection outlet, wherein 
the opposing member opposes to such a side of the movable member as is 
near to the heat generating surface when the free end of the movable 
member is displaced by the bubble; and transporting means for transporting 
a recording material for receiving the liquid ejected from the liquid 
ejecting head. 
According to a further aspect of the present invention, there is provided a 
head kit comprising: a liquid ejection head including; a substrate having 
a heat generating surface for generating heat for generating a bubble in 
liquid; a movable member having a free end; an ejection outlet for 
ejecting the liquid using the generation of the bubble, the ejection 
outlet being opposed to the substrate with the movable member interposed 
therebetween; an opposing member cooperable with the movable member to 
direct the bubble toward the ejection outlet, wherein the opposing member 
opposes to such a side of the movable member as is near to the heat 
generating surface when the free end of the movable member is displaced by 
the bubble; and a liquid container containing the liquid to be supplied to 
the liquid ejecting head. 
According to a further aspect of the present invention, there is provided a 
head kit comprising: a liquid ejection head including; a having a heat 
generating surface for generating heat for generating a bubble in liquid; 
a movable member having a free end; an ejection outlet for ejecting the 
liquid using the generation of the bubble, the ejection outlet being 
opposed to the heat generating surface with the movable member interposed 
therebetween; an opposing member cooperable with the movable member to 
direct the bubble toward the ejection outlet, wherein the opposing member 
opposes to such a side of the movable member as is near to the heat 
generating surface when the free end of the movable member is displaced by 
the bubble; and a liquid container containing the liquid to be supplied to 
the liquid ejecting head. 
According to a further aspect of the present invention, there is provided a 
liquid ejecting method, comprising: providing a substrate having a heat 
generating surface for generating heat for generating a bubble in liquid; 
providing a movable member having a free end; providing an ejection outlet 
member having an ejection outlet for ejecting the liquid using the 
generation of the bubble, the ejection outlet being opposed to the 
substrate with the movable member interposed therebetween; wherein the 
ejection outlet member and the substrate define a liquid path therebetween 
and do not cross each other in the path; disposing the free end of the 
movable member at a downstream side with respect to a direction of flow of 
the liquid to the ejection outlet; and wherein the bubble displaces the 
free end of the movable member, and grows toward the ejection outlet to 
eject the liquid. 
According to a further aspect of the present invention, there is provided a 
liquid ejection head comprising: a substrate having a heat generating 
surface for generating heat for generating a bubble in liquid; a movable 
member having a free end; an ejection outlet member having an ejection 
outlet for ejecting the liquid using the generation of the bubble, the 
ejection outlet being opposed to the substrate with the movable member 
interposed therebetween; wherein the ejection outlet member and the 
substrate define a liquid path therebetween and do not cross each other in 
the path; an opposing member cooperable with the movable member to direct 
the bubble toward the ejection outlet, wherein the opposing member opposes 
to such a side of the movable member as is near to the heat generating 
surface when the free end of the movable member is displaced by the 
bubble; the heat generated by the heat generating surface causes film 
boiling of liquid to create the bubble. 
According to a further aspect of the present invention, there is provided a 
recording system using the recording apparatus. 
According to the present invention, a movable member having a free end 
interposed between a heat generation surface of a heat generating element 
and an ejection outlet, displaces toward the ejection outlet by the 
pressure produced by the bubble generated by the heat generation surface. 
As a result, the movable member cooperates with a member opposed thereto, 
and concentrates the pressure produced by the bubble toward the ejection 
outlet as if it squeeze the fluid communication path between the heat 
generation surface and the ejection outlet. Therefore, the liquid can be 
ejected with high ejection efficiency, high ejection power, and high shot 
accuracy onto the recording material. The movable member is also effective 
to reduce the influence of the back wave, and therefore, the refilling 
property of the liquid can be improved. Therefore, there is provided the 
high responsivity, stable growth of the bubble and the stable ejection 
property of the liquid droplet during continuous liquid ejections, thus 
accomplishing high speed recording and high image quality recording. 
By using the liquid which is easy to generate the bubble and which does not 
easily produce accumulated material such as cogation in the liquid 
ejecting head in the two-flow-path structure, the latitude of the 
selection of the ejection liquid is increased. Additionally liquid which 
is relatively influenced by heat is usable without the influence. 
According to the manufacturing method of the liquid ejecting head of the 
present invention, such liquid ejecting heads can be manufactured with 
high precision, with smaller number of parts at low cost. 
The present invention provides a recording system or liquid ejecting device 
with high ejection efficiency. 
According to the present invention, the head can be reused. 
These and other objects, features and advantages of the present invention 
will become more apparent upon a consideration of the following 
description of the preferred embodiments of the present invention taken in 
conjunction with the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the accompanying drawings, the embodiments of the present 
invention will be described. 
(Embodiment 1) 
FIG. 1 is a schematic cross-sectional view of a liquid ejecting head 
according to an embodiment of the present invention. FIG. 2 is a FIG. 2 is 
a partly broken schematic partial view of the liquid ejecting head of FIG. 
1. 
The liquid ejecting head of this embodiment is a so-called side shooter 
type head, wherein the ejection outlet 11 is faced substantially parallel 
to a heat generation surface of the heat generating element 2. The heat 
generating element 2 has a size of 48 .mu.m.times.46 .mu.m and is in the 
form of a heat generating resistor. It is mounted on a substrate 1, and 
generates thermal energy used to generate a bubble by film boiling of 
liquid as disclosed in U.S. Pat. No. 4,723,129. The ejection outlet 11 is 
formed in an orifice plate 14 which is an ejection outlet portion 
material. The orifice plate 14 is manufactured from nickel through 
electro-forming. 
A liquid flow path 3b is provision between the orifice plate 14 and the 
substrate 1 so that it is directly in fluid communication with the 
ejection outlet 11 to flow the liquid therethrough. In this embodiment, 
water base ink (mixture liquid of water and ethanol) as liquid to be 
ejected. 
The liquid flow path 3b is provided with a movable portion 6 in the form of 
a flat plate cantilever so as to cover the heat generating element 2 and 
to face it. Here, the movable portion is called "movable member". The 
movable portion 6 is positioned adjacent an upward projection space of the 
heat generation surface in a direction perpendicular to the heat 
generation surface of the heat generating element 2. The movable portion 6 
is of elastic material such as metal. In this embodiment, it is of nickel 
having a thickness of 5 .mu.m. An one end 5a of the movable portion 6 is 
supported and fixed on a supporting member 5b. The supporting member 5b is 
formed by patterning photosensitive resin material on the substrate 1. 
Between the movable portion 6 and the heat generating surface, this is 
provided a clearance of approx. 15 .mu.m. 
Reference numeral 15a designates a wall member as an opposing member 
opposed to such a surface of the movable portion 6 as is nearer to the 
heat generation surface when the movable portion 6 is opened. The wall 
member 15a and a free end 6a of the movable portion 6 are opposed to each 
other with a gap therebetween of approx. 2 .mu.m in the form of a slit 8. 
The movable portion 6 has a fixed end (fulcrum) at an upstream side with 
respect to the flow of the liquid from a common liquid chamber to the 
ejection outlet 11 through the supply passage 4b and the movable portion 
6, and has a free end 6a at the downstream side. The fixed end 6b 
functions as a base portion (fulcrum) upon opening of the movable portion 
6. 
In this embodiment, the slit 8 is narrow enough to prevent the bubble from 
expanding therethrough before the movable portion 6 displaces. Thus, it is 
formed around the movable portion 6 but provides substantial sealed 
structure. At least the free end 6a of the movable portion 6 is disposed 
within a region to which the pressure due to the bubble extends. In FIG. 
1, "A" designates an upper side region (ejection outlet side) of the 
movable portion 6 in a stable state, and "B" designates a lower side (heat 
generating element side) region. 
When heat is generated at the heat generation surface of the heat 
generating element 2, and a bubble is generated in the region B, the free 
end 6a of the movable portion 6 is instantaneously moved in the direction 
of the arrow in FIG. 1 namely toward the region A with the base portion 6b 
functioning as a fulcrum by the pressure resulting from the generation and 
growth of the bubble and by the expanding bubble per se. By this, the 
liquid is ejected out through the ejection outlet 11. 
In FIG. 2, reference numeral 18 designates wiring electrode for applying an 
electric signal to the heat generating element 2 which is an 
electrothermal transducer, and it is mounted on the substrate 1. 
The description will be made as to ejecting operation of the liquid 
ejecting head according to this embodiment. FIGS. 3A-3D are schematic 
sectional views illustrating ejecting operation of the liquid ejecting 
head according to this embodiment. In FIGS. 3A-3D, supporting member 5b is 
omitted for simplicity. 
FIG. 3A shows a state in which the heat generating element 2 has not yet 
been supplied with energy such as electric energy, namely, in which the 
heat generating element has not yet generated the heat (initial state). As 
shown FIG. 3A, the free end 6a is opposed to the slit 8 of a predetermined 
size. 
FIG. 3B shows a state in which the heat generating element 2 is supplied 
with the electric energy or the like to generate the heat, which produces 
a bubble 7 by film boiling, and the bubble is growing. The pressure 
resulting from the generation of the bubble and the growth thereof is 
mainly propagated to the movable portion 6. The mechanical displacement of 
the movable portion 6 is contributable to the ejection of the ejection 
liquid from the ejection outlet. 
FIG. 3C shows a state in which the bubble 7 has further grown. As will be 
understood, the movable portion 6 is further displaced toward the ejection 
outlet with the growth of the bubble 7. By the displacement of the movable 
portion 6, the ejection outlet side region A and the heat generating 
element side region B are in much freer communication with each other than 
the initial state. In this state, the fluid communication path between the 
heat generation surface and the ejection outlet is choked to a proper 
extent by the movable portion 6 so as to concentrate the force of the 
bubble expansion toward the ejection outlet. In this manner, the pressure 
wave resulting from the growth of the bubble is transmitted concentratedly 
in the upward direction. By such direct propagation of the pressure wave 
and the mechanical displacement of the movable portion 6 described in 
conjunction with FIG. 4B, the ejection liquid is ejected at high speed and 
with high ejection power and further with high ejection efficiency through 
the ejection outlet 11 in the form of a droplet 11a (FIG. 3D). 
In FIG. 3C, a part of the bubble generated at the heat generating element 
side region B extends to the ejection outlet side region A. The ejection 
power can be further increased if the clearance from the surface of the 
substrate 1 or the heat generation surface of the heat generating element 
2 to the movable portion 6 is so selected as to permit the bubble to 
extend into the ejection outlet side region A. In order to permit the 
bubble to extend toward the ejection outlet beyond the initial position of 
the movable portion 6, it is desirable that the height of the heat 
generating element side region B is smaller than the height of the maximum 
bubble state, more particularly several .mu.m-30 .mu.m. 
FIG. 3D shows a state in which the bubble 7 is collapsing by the decrease 
of the inside pressure. The movable portion 6 restores its initial 
position by the negative pressure resulting from the contraction of the 
bubble and the restoring force due to the spring property of the movable 
portion per se. With this, the liquid flow path 3b is quickly supplied 
with the amount of the liquid ejected out. In the liquid flow path 3b, 
there is hardly any influence of the back wave due to the bubble, and 
liquid supply is carried out concurrently with the closing of the movable 
portion 6, and therefore, the liquid supply is not obstructed by the 
movable portion. 
The description will be made as to refilling of the liquid in the liquid 
ejecting head of this embodiment. 
When the bubble 7 is in the collapsing process after the maximum volume 
thereof is reached, the volume of the liquid compensating for the 
disappeared bubble volume flows both from the ejection outlet 11 side and 
the liquid flow path 3b side. The volume of the bubble at the upper side 
(ejection outlet side) beyond the initial position of the movable portion 
6 is W1, and that of the lower side (heat generating element side) is 
movable portion (W1+W2=W). When the movable portion 6 restores its initial 
position, the retraction of the meniscus at the ejection outlet for 
compensating a part of W1 stops, thereafter, the compensation for the 
remaining W2 is mainly effected by the liquid supply between the movable 
portion 6 and the heat generation surface. By this, the retraction of the 
meniscus at the ejection outlet can be reduced. 
In this embodiment, the compensation of the volume W2 can be forcedly 
effected mainly through the liquid flow path 3b along the heat generation 
surface of the heat generating element, using the pressure change upon the 
collapse of bubble, and therefore, the quicker refilling is possible. In 
the case that the refilling is effected using the pressure upon the 
collapse of bubble in a conventional head, the vibration of the meniscus 
is large with the result of the deterioration of the image quality, but in 
this embodiment, the vibration of the meniscus can be minimized since the 
communication between the ejection outlet side region A and the heat 
generating element side region B is suppressed. By this, the improvement 
of the image quality and the high speed recording are expected. 
The surface of the substrate 1 is substantially flush with the heat 
generation surface of the heat generating element 2, that is, the heat 
generating element surface is not stepped down. In such a case, the supply 
of the liquid to the region B occurs along the surface of the substrate 1. 
Therefore, the stagnation of the liquid on the heat generation surface of 
the heat generating element 2 is suppressed, and the precipitated bubble 
resulting from the dissolved gasses or the residual bubble having not 
collapsed, are removed, and the heat accumulation in the liquid is not too 
much. Therefore, more stabilized generation of the bubble can be repeated 
at high speed. In this embodiment, the surface of the substrate 1 is of 
flat inner wall, but this is not limiting if the inner wall has such a 
smooth surface that the liquid does not stagnate and that an eddy flow 
does not occur in the liquid. 
(Embodiment 2) 
FIG. 4 is a schematic sectional view of a major part of another embodiment 
of the liquid ejecting head of the present invention. In FIG. 4, 
supporting member 5b is omitted for simplicity. 
This embodiment is different from Embodiment 1 in that the movable portion 
6 is thin to provide higher flexibility. By this, as shown in FIG. 4 by 
the broken line, the movable portion 6 displaced by the bubble is slightly 
bent toward the ejection outlet 11. If the movable portion is flexible, 
the movable portion can be deflected to a great extent even with 
relatively low bubble generation pressure, so that the bubble generation 
pressure can be further efficiently directed to the ejection outlet. In 
this embodiment, too, a high ejection power and high ejection efficiency 
liquid ejecting head is provided. 
(Embodiment 3) 
FIG. 5 is a schematic sectional view of a major part of another embodiment. 
FIG. 6 is a partial schematic partly broken perspective view of a liquid 
ejecting head shown in FIG. 5. The movable portion 6 of the head of this 
embodiment is not of a single structure but has a couple structure. The 
pressure of the bubble displaces a pair of movable portions 6 to permit 
the pressure to transmit toward the ejection outlet 11 disposed above the 
movable portion 6. One of the movable portions 6 function as the movable 
member and the on the other hand functions as an opposing member, so that 
the bubble generation pressure is efficiently directed toward the ejection 
outlet. In this embodiment, too, a high ejection power and high ejection 
efficiency liquid ejecting head is provided. 
(Embodiment 4) 
FIG. 7 is an is a schematic cross-sectional view of a liquid ejecting head 
of a further embodiment of the present invention. FIG. 8 is schematic 
portion partly broken perspective view of a liquid ejecting head of FIG. 
7. 
The liquid ejecting head of this embodiment is a side shooter type head 
wherein the heat generating element 2 is faced to the ejection outlet 11. 
The heat generating element 2 has a size of 48 .mu.m.times.46 .mu.m and is 
in the form of a heat generating resistor. It is mounted on a substrate 1, 
and generates thermal energy used to generate a bubble by film boiling of 
liquid as disclosed in U.S. Pat. No. 4,723,129. The ejection outlet 11 is 
provided in an orifice plate 14 which is an ejection outlet portion 
material. The orifice plate 14 is of nickel and manufactured through 
electro-forming. 
A first liquid flow path 3 is provided below the orifice plate 14 so that 
it is directly in fluid communication with the ejection outlet 11. On the 
other hand, on the substrate 1, a second liquid flow path 4 is provision 
for the flow of the bubble generation liquid. Between the first liquid 
flow path 3 and the second liquid flow path 4, a partition or separation 
wall 5 for separating the liquid flow paths is provided. The separation 
wall 5 is of elastic material such as metal. In this embodiment, the 
separation wall 5 is of nickel having a thickness of 5 .mu.m. The 
separation wall 5 separates the ejection liquid in first liquid flow path 
3 and the bubble generation liquid in the second liquid flow path 4. 
The ejection liquid is supplied to the first liquid flow path 3 through the 
first supply passage 12a from the first common liquid chamber 12 
containing the ejection liquid. The bubble generation liquid is supplied 
to the second liquid flow path 4 through the second supply passage 13a 
from the second common liquid chamber 13 containing the bubble generation 
liquid. The first common liquid chamber 12 and the second common liquid 
chamber 13 are separated by a partition 1a. In this embodiment, the 
ejection liquid supplied to the first liquid flow path 3 and the bubble 
generation liquid supplied to the second liquid flow path 4 are both water 
base ink (mixed liquid of ethanol and water). 
The separation wall 5 is disposed adjacent the portion of the projected 
space of the heat generation surface of the heat generating element 2 
perpendicular to the heat generation surface, and has a pair of movable 
portions 6 of flat plate cantilever configuration, one of which is a 
movable member and the other is an opposing member opposed to the movable 
member. The movable portion 6 and the heat generating surface a disposed 
with a clearance of 15 .mu.m approx. The free ends 6a of the movable 
portions 6 are opposed to each other with a gap of approx. 2 .mu.m (slit 
8). Designated by 6b is a base portion functioning as a base portion upon 
opening of the movable portions 6. Slit 8 is formed in a plane including a 
line connecting a center portion of the heat generating element 2 and the 
center portion of the ejection outlet 11. In this embodiment, the slit 8 
is so narrow that the bubble does not extend through the slit 8 around the 
movable portions 6 before the movable portion 6 is displaced, when the 
bubble growths. At least the free end 6a of the movable portion 6 is 
disposed within a region to which the pressure due to the bubble extends. 
In FIG. 7, "A" designates an upper side region(ejection outlet side) of 
the movable portion 6 in a stable state, and "B" designates a lower 
side(heat generating element side) region. 
When heat is generated at the heat generation surface of the heat 
generating element 2, and a bubble is generated in the region B, the free 
end 6a of the movable portion 6 is instantaneously moved in the direction 
of the arrow in FIG. 1 namely toward the region A with the base portion 6b 
functioning as a fulcrum by the pressure resulting from the generation and 
growth of the bubble and by the expanding bubble per se. By this, the 
liquid is ejected out through the ejection outlet 11. 
Designated by reference numeral 18 in FIG. 8 is a wiring electrode for 
applying the electric signal to the heat generating element 2 which is an 
electrothermal transducer mounted on the substrate 1. 
The description will be made as to the positional relation between the 
movable portion 6 and the second liquid flow path 4 in this embodiment. 
FIG. 9A is a schematic top plan view of the movable portion 6 as seen from 
the orifice plate 14 side. FIG. 9B is a schematic top plan view of the 
bottom portion of the second liquid flow path 4, as seen from the 
separation wall 5 side. FIG. 9C is a schematic top plan view of the 
movable portion 6 through the second liquid flow path 4, as seen from the 
orifice plate 14 side. In these Figures, the front side of the sheet of 
the drawing is an ejection outlet 11 side. 
In this embodiment, throat portions 9 are formed on both sides of the heat 
generating element 2 in the second liquid flow path 4. By the throat 
portions 9, the adjacent region of the heat generating element 2 of the 
second liquid flow path 4 has a chamber (bubble generation chamber) 
structure such that escape of the pressure upon the bubble generation 
along the second liquid flow path 4 is suppressed. 
When a throat portion is provided in the liquid flow path to suppress 
escape of the pressure upon the bubble generation in a conventional head, 
the flow path cross-sectional area at the throat portion should not be too 
small in view of the refilling property of the liquid to be ejected. 
However, in this embodiment, most of the ejected liquid is the ejection 
liquid in the first liquid flow path, and the bubble generation liquid in 
the second liquid flow path having the heat generating element is not 
ejected so much, and therefore, the filling of the bubble generation 
liquid into the region B of the second liquid flow path may relatively 
small. Therefore, the clearance of the flow passage wall in the throat 
portion 9 may be very narrow, such as several .mu.m. By this, the pressure 
upon the bubble generation generated in the second liquid flow path 4 can 
be directed concentratedly toward the movable portion 6 without escape to 
the circumference. Such pressure can be used as the ejection power through 
the movable portion 6, and therefore, further high ejection efficiency and 
ejection power can be accomplished. 
The description will be made as to the ejecting operation of the liquid 
ejecting head in this embodiment. FIG. 10A-FIG. 10D are schematic 
sectional views of the liquid ejecting head illustrating the ejecting 
operation in this embodiment. In this embodiment, the ejection liquid to 
be supplied to the first liquid flow path 3 and the bubble generation 
liquid to be supplied to the second liquid flow path 4, are the same water 
base ink. 
FIG. 10A shows a state before the energy such as the electric energy is 
applied to the heat generating element 2, namely, the initial state before 
the heat generating element generates heat. As shown in FIG. 10A, the free 
ends 6a of the separation walls 5 above the heat generating element 2, are 
faced to each other through a slit 8 to separate the ejection liquid in 
the first liquid flow path 3 and the bubble generation liquid in the 
second liquid flow path 4. 
FIG. 10B shows a state in which the heat generating element 2 is supplied 
with the electric energy or the like, and the heat generating element 2 
generate the heat which produces film boiling in the liquid so that the 
bubble 7 is generated and is expanded. The pressure resulting from the 
generation and the growth of the bubble is mainly propagated to the 
movable portion 6. The mechanical displacement of the movable portion 6 is 
contributable to the ejection of the ejection liquid from the ejection 
outlet. 
FIG. 10C shows a state wherein the bubble 7 has further grown. With the 
growth of the bubble 7, the movable portion 6 is further displaced toward 
the first liquid flow path 3 side with its base portion 6b functioning as 
fulcrum. By the displacement of the movable portion 6, the first liquid 
flow path 3 and the second liquid flow path 4 are in substantial fluid 
communication with each other. In this state, the fluid communication path 
between the heat generation surface and the ejection outlet is choked to a 
proper extent by the movable portion 6 so as to concentrate the force of 
the bubble expansion toward the ejection outlet. In this manner, the 
pressure wave produced by the growth of the bubble is concentratedly 
transmitted right upward toward the ejection outlet 11 in fluid 
communication with the first liquid flow path 3. By the direct propagation 
of the pressure wave and the mechanical displacement of the movable 
portion 6 described in conjunction with FIG. 10B, the ejection liquid is 
ejected through the ejection outlet 11 at high speed and with high 
ejection power and with high ejection efficiency as a droplet 11a (FIG. 
10D). 
In FIG. 10C, with the displacement of the movable portion 6 to the first 
liquid flow path 3 side, a part of the bubble generated at the region B in 
the second liquid flow path 4 extends into the first liquid flow path 3 
side. Thus, the height of the second liquid flow path 4 (a clearance from 
the surface of the substrate 1 or the heat generating surface of the heat 
generating element 2 to the movable portion 6) is such that the bubble 
extending into the first liquid flow path 3 side, by which the ejection 
power is further improved. In order to extend the bubble into the first 
liquid flow path 3, it is desirable the height of the second liquid flow 
path 4 is made smaller than the height of the maximum bubble, for example, 
several .mu.m-30 .mu.m. 
FIG. 10D shows a state in which the bubble 7 is collapsing by the decrease 
of the inside pressure. The movable portion 6 restores its initial 
position by the negative pressure resulting from the contraction of the 
bubble and the restoring force due to the spring property of the movable 
portion per se. With this, the first liquid flow path 3 is quickly 
supplied with the amount of the liquid ejected out. In the first liquid 
flow path 3, there is hardly any influence of the back wave due to the 
bubble, and liquid supply is carried out concurrently with the closing of 
the movable portion 6, and therefore, the liquid supply is not obstructed 
by the movable portion. Accordingly, the inside in the FIG. 10D is not 
pressure so much, and therefore, a small amount of decrease is enough. 
The description will be made as to the refilling of the liquid in the 
liquid ejecting head according to this embodiment. 
When the bubble 7 is in the bubble collapse process after the maximum 
volume thereof, the volume of the liquid compensating for the disappeared 
bubble volume flows both from the ejection outlet 11 side side, the first 
liquid flow path 3b side and the second liquid flow path 4. The volume of 
the bubble at the upper side (ejection outlet side) beyond the initial 
position of the movable portion 6 is W1, and that of the lower side (heat 
generating element side) is movable portion (W1+W2=W). When the movable 
portion 6 restores its initial position, the retraction of the meniscus at 
the ejection outlet for compensating a part of W1 stops, thereafter, the 
compensation for the remaining W2 is mainly effected by the liquid supply 
in the second liquid flow path 4. By this, the degree of retraction of the 
meniscus in the ejection outlet, can be suppressed. 
In this embodiment, the compensation of the volume W2 can be forcedly 
effected mainly through the second liquid flow path along the heat 
generation surface of the heat generating element, using the pressure 
change upon the collapse of bubble, and therefore, the quicker refilling 
is possible. In the case that the refilling is effected using the pressure 
upon the collapse of bubble in a conventional head, the vibration of the 
meniscus is large with the result of the deterioration of the image 
quality, but in this embodiment, the vibration of the meniscus can be 
minimized since the communication between the region of the first liquid 
flow path 3 of the ejection outlet side and the second liquid flow path 4, 
is suppressed by the movable portion. By this, the improvement of the 
image quality and the high speed recording are expected. 
The surface of the substrate 1 is substantially flush with the heat 
generation surface of the heat generating element 2, that is, the heat 
generating element surface is not stepped down. In such a case, the supply 
of the liquid to the region B occurs along the surface of the substrate 1. 
Therefore, the stagnation of the liquid on the heat generation surface of 
the heat generating element 2 is suppressed, and the precipitated bubble 
resulting from the dissolved gasses or the residual bubble having not 
collapsed, are removed, and the heat accumulation in the liquid is not too 
much. Therefore, more stabilized generation of the bubble can be repeated 
at high speed. In this embodiment, the surface of the substrate 1 is of 
flat inner wall, but this is not limiting if the inner wall has such a 
smooth surface that the liquid does not stagnate and that an eddy flow 
does not occur in the liquid. 
The description will be made as to the pressure propagation from the bubble 
in the liquid ejecting head of this embodiment, as compared with a 
conventional example. FIG. 11A is a schematic sectional view illustrating 
pressure propagation from the bubble in the liquid ejecting head of this 
embodiment. FIG. 11B is a schematic sectional view illustrating pressure 
propagation from the bubble in the liquid ejecting head of the 
conventional. 
In a representative conventional head showed in FIG. 11B, there is not 
obstructing material against the propagation of the pressure produced by 
the bubble 7, in the propagation direction. Therefore, the direction of 
the pressure propagation of the bubble is widely scattered along the 
substantially normal line direction of the surface of the bubble, as 
indicated by V.sub.1 -V.sub.8. Among these directions, the pressure 
component directed to the ejection outlet which is most influential to the 
liquid ejection, is V.sub.8 -V.sub.6, namely, the pressure propagation 
component close to the ejection outlet. Particularly, V.sub.4 and V.sub.5 
are closest to the ejection outlet, so that they work efficiently for the 
liquid ejection, but V.sub.3 and V.sub.6 have relatively small component 
directed to the ejection outlet. Here, V.sub.A and V.sub.B are the 
pressure propagation component in the opposite direction along the liquid 
flow path. 
In the case of this embodiment showed in FIG. 11A, the movable member 6 
directs the pressure propagation component V.sub.3 -V.sub.6 of the bubble 
toward the ejection outlet, and therefore, the pressure of the bubble 7 
acts directly and efficiently. The bubble per se growths toward the 
ejection outlet. In this manner, the movable portion controls not only the 
pressure propagation direction but also the growth of the bubble per se, 
so that the ejection efficiency, ejection power, ejection speed and so on 
are significantly ejection powered. 
Here, V.sub.A1 and V.sub.B1 are pressure components along the first liquid 
flow path in the opposite directions from each other, and V.sub.A and 
V.sub.B are pressure components along the second liquid flow path in the 
opposite directions from each other. In this embodiment, the movable 
portion 6 suppresses the back wave, and therefore, V.sub.A1 and V.sub.B1 
are smaller than in the conventional device. The bubble is directed toward 
the ejection outlet, and therefore, V.sub.A and V.sub.B are smaller than 
in the conventional device. As a result, V.sub.A1 +V.sub.A and V.sub.B1 
+V.sub.B are smaller than V.sub.A and V.sub.B in the conventional device. 
(Embodiment 5) 
FIG. 12 is a schematic sectional view of a major part of a liquid ejecting 
head according to another embodiment of the present invention. This 
embodiment is different from Embodiment 4 in that the movable portion 6 is 
thin to give higher flexibility. By this, as shown in FIG. 12 by the 
broken line, the movable portion 6 displaced by the bubble is slightly 
bent toward the ejection outlet 11. If the movable portion is flexible, 
the movable portion can be deflected to a great extent even with 
relatively low bubble generation pressure, so that the bubble generation 
pressure can be further efficiently directed to the ejection outlet. In 
this embodiment, too, a high ejection power and high ejection efficiency 
liquid ejecting head is provided. 
(Embodiment 6) 
FIG. 13A is a schematic sectional view of a major part of a liquid ejecting 
head of the present invention according to a further embodiment. FIG. 13B 
is a schematic top plan view of the movable portion used in this 
embodiment, as seen from the ejection outlet side. This embodiment is 
different from Embodiment 4 in that a trench or pit type liquid passage 4a 
enclosed by walls in four sides is in place of the second liquid flow path 
4. In this embodiment, after liquid ejection, the liquid is supplied into 
the pit type liquid passage 4a mainly from the first liquid flow path 3 
through the opening 6c in the movable member 6. The size of the opening 6c 
will suffice if it permits flow of the ink without escaping the bubble. 
In this embodiment, the escape of the bubble generation pressure toward 
upstream side along the lower part of the movable portion 6. Furthermore, 
upon the collapse of bubble, the amount of the ink to be refilled is only 
the one corresponding to the volume of the pit type liquid passage, so 
that the refilling amount may be small, and the high speed responsivity 
can be accomplished. In this embodiment, the high ejection power and high 
ejection efficiency liquid ejecting head can be prevented. 
(Embodiment 7) 
FIG. 14A is a schematic sectional view of a major part of a liquid ejecting 
head according to a further embodiment of the present invention. The 
movable portion 6 of the head of this embodiment is not a dual type, but a 
single type. The first liquid flow path 3 at the free end 6a side of the 
movable portion 6 is closed by a wall 15a (opposing member opposed to the 
movable member), so that the pressure produced by the bubble expands 
toward the ejection outlet 11 thereabove by deflection of the movable 
portion 6. The movable portion 6 in this embodiment is a single member, 
manufacturing is easy and latitude in the designing is large. 
FIG. 14B is a schematic sectional view illustrating the generation, and so 
on, of the bubble 7 in the liquid ejecting head according to this 
embodiment. As shown in this Figure, a part of the bubble generated in the 
region B of the second liquid flow path 4 expands into the first liquid 
flow path 3 side with the displacement of the movable portion 6 into the 
first liquid flow path 3 side. Thus, the height of the second liquid flow 
path 4 (a clearance from the surface of the substrate 1 or the heat 
generating surface of the heat generating element 2 to the movable portion 
6) is such that the bubble extending into the first liquid flow path 3 
side, by which the ejection power is further improved. In order to extend 
the bubble into the first liquid flow path 3, it is desirable the height 
of the second liquid flow path 4 is made smaller than the height of the 
maximum bubble, for example, several .mu.m-30 .mu.m. In this embodiment, 
the high ejection power and high ejection efficiency liquid ejecting head 
can be prevented. 
(Embodiment 8) 
FIG. 15A is a schematic sectional view illustrating major part of a liquid 
ejecting head according to a further embodiment of the present invention. 
FIG. 15B is a schematic top plan view of the movable portion of this 
embodiment, as seen from the ejection outlet side. This embodiment is 
different from Embodiment 4 in that a pit type liquid passage 4a enclosed 
by walls in four sides is in place of the second liquid flow path 4. In 
this embodiment, after liquid ejection, the liquid is supplied into the 
pit type liquid passage 4a mainly from the first liquid flow path 3 
through the opening 6c in the movable member 6. The size of the opening 6c 
will suffice if it permits flow of the ink without escaping the bubble. 
In this embodiment the pressure for deflecting up the valve and the 
pressure of the bubble are both directed toward the ejection outlet. The 
movable portion 6 returns to the initial position substantially 
simultaneously with the collapse of bubble, and therefore, the degree of 
the retraction of the ink meniscus can be minimized, so that the the ink 
is smoothly supplied to the heat generating surface from the upstream side 
by the forced refilling function of the ink by the collapse of bubble. By 
this, a liquid ejecting head with high ejection power and high ejection 
efficiency, can be prevented. 
(Embodiment 9) 
FIG. 16A is a FIG. 16A is a schematic sectional view of a major part of a 
liquid ejecting head according to a further embodiment of the present 
invention. FIG. 16B is an is a schematic top plan view of a movable 
portion used in movable portion, as seen from the ejection outlet side. 
This embodiment is different from Embodiment 7 in that a pit type liquid 
passage 4a enclosed by walls in four sides is in place of the second 
liquid flow path 4. In this embodiment, after liquid ejection, the liquid 
is supplied into the pit type liquid passage 4a mainly from the first 
liquid flow path 3 through the opening 6c in the movable member 6. The 
size of the opening 6c will suffice if it permits flow of the ink without 
escaping the bubble. 
In this embodiment, the escape of the bubble generation pressure toward the 
upstream side along the lower part of the movable portion 6, can be 
suppressed, and therefore, so that the bubble generation pressure can be 
efficiently directed toward the ejection outlet. Further more, upon the 
collapse of bubble, the amount of the ink to be refilled is only the one 
corresponding to the volume of the pit type liquid passage, so that the 
refilling amount may be small, and the high speed responsivity can be 
accomplished. According to this embodiment, too, a liquid ejecting head of 
high ejection power and high ejection efficiency can be prevented. 
HEAD EXAMPLE 1 
FIG. 17 is a schematic perspective view of an example of a liquid ejecting 
head according to an embodiment of the present invention, which has a 
plurality of ejection outlets and a plurality of liquid flow paths in 
fluid communication therewith, respectively. The liquid ejecting head is 
formed by a substrate 1, a separation wall 5 and an orifice plate 14 which 
are laminated with gaps. Substrate 1 has a supporting member of metal such 
as aluminum and a plurality of heat generating elements 2. Heat generating 
element 2 is in the form of an electrothermal transducer element 
generating heat for generating a bubble by film boiling in the bubble 
generation liquid supplied to the second liquid flow path 4. The substrate 
1 is provided with a wiring electrode for supplying the electric signal to 
the heat generating element 2, and function elements such as transistor, 
diode, latch, shift register for driving the heat generating elements 2 
selectively. On the heat generating element 2, a protection layer (omitted 
in the Figure) for protecting the heat generating element 2 is provided. 
The separation wall 5 is provided with a pair of movable portions 6 so as 
to oppose to the heat generating element 2. Above the separation wall 5, 
an orifice plate 14 having ejection outlets 11 is provided with flow 
passage walls 15 for constituting the first liquid flow paths 3 sandwiched 
therebetween. 
In FIG. 17, reference numeral 12 designates a first common liquid chamber 
for supplying the ejection liquid through the first supply passage 12a to 
the first liquid flow paths 3. Designated by 13 is second common liquid 
chamber for supplying the bubble generation liquid through the second 
supply passage 13a to the second liquid flow paths 4. Thus, the first 
common liquid chamber 12 is in fluid communication with the plurality of 
first liquid flow paths 3 separated by the flow passage walls 15 on the 
separation wall 5. The second common liquid chamber 13 is in fluid 
communication with the plurality of second liquid flow paths 4 separated 
by the plurality of flow passage walls (omitted in the FIG. for 
explanation purpose) on the substrate 1. 
In the manufacturing of the liquid ejecting head shown in FIG. 17, a dry 
film having a thickness of 15 .mu.m (solid photosensitivity resin 
material) is placed on the substrate 1, and is patterned to form the flow 
passage walls for constituting the second liquid flow paths 4. The 
material of the flow passage wall may be any if it exhibits anti-solvent 
property against the bubble generation liquid, and the flow passage wall 
can be formed. Examples of such materials include liquid photosensitive 
resin material in addition to the dry film. Other examples are resin 
material such as polysulfone or polyethylene or metal such as gold, 
silicon, nickel, and glass. Thereafter, the substrate 1 and the separation 
wall 5 are connected to form an integral substrate and separation wall 
combination while the heat generating element 2 and the movable portion 6 
are correctly positioned with each other. 
The orifice plate 14 having the ejection outlets 11 are formed from nickel 
through electro-forming. The orifice plate 14 may be a grooved member 
having ejection outlets formed by projecting eximer laser to a mold of 
resin integrally having the first liquid flow path 3. The first liquid 
flow path 3 is formed by placing a dry film having a thickness of 25 .mu.m 
on the back side of the orifice plate 14 and patterning it. Thereafter, 
the orifice plate 14 is connected with the integral substrate and 
separation wall combination, while the ejection outlet 11 and the movable 
portion 6 are correctly positioned relative to each other. 
HEAD EXAMPLE 2 
FIG. 18 is a schematic perspective view of a liquid ejecting head according 
to an embodiment of the present invention. The 1 of this embodiment is 
different from the foregoing head is in that the movable portion 6 is an 
independent member rather than a pair. The defect 15d having the flow 
passage wall 15 functions as an opposing member. In this embodiment, a 
liquid ejecting head with the high ejection power and high ejection 
efficiency, is provided. 
(Movable Portion and Separation Wall) 
FIG. 19A-FIG. 19C are schematic top plan views of liquid ejecting heads 
having a movable portions according to further embodiments. FIG. 19A shows 
an example, wherein the movable portion 6 of the separation wall 5 is 
rectangular. FIG. 19B shows an example, wherein the movable member is 
rectangular with narrowed base portion 6b functioning as the fulcrum upon 
the displacement or deflection. FIG. 19C shows an example, wherein the 
movable member is rectangular with wider base portion 6b functioning as 
the fulcrum of the displacement than the free end 6a side. 
With the use of the movable portion 6 as shown in FIG. 19B, the operation 
of the displacement is easier. With the movable portion 6 as shown in FIG. 
19C, the durability of the movable portion is high. From the standpoint of 
both of easiness of the operation of the movable portion and the 
durability of the movable portion, the width of the base portion 6b side 
functioning as the fulcrum, as shown in FIG. 9A, is desirably narrowed 
arcuately. 
FIG. 20 is a schematic top plan view of the rectangular movable portion 6 
and the heat generating element 2 shown in FIG. 19A, as seen from the 
ejection outlet side, to show the positional relation therebetween. In 
order to effectively use the bubble generation pressure, the two movable 
portions 6 are extended in the different directions so that the portion 
right above the effective bubble generating region of the heat generating 
element 2 is covered by the movable portion, that is, the movable ends 
thereof are opposed to each other. In this embodiment, the movable 
portions 6 have the same configurations and are arranged symmetrically, 
but a plurality of movable members having different configurations may be 
used. The movable portions may be asymmetrical if the durability of the 
movable portion is high, and the ejection efficiency is high. By making 
the total area of the movable portion larger than the total area of the 
heat generating surface of the heat generating element and by positioning 
the fulcrum of the movable portion outside the region of effective bubble 
generating region of the heat generating element, the ejection efficiency 
and the durability of the liquid ejecting head are improved. 
In the head having the opposed movable portions as shown in FIG. 7 and the 
like, it is preferable that the slit is relatively narrow, from the 
standpoint of the improvement in the ejection efficiency. It is preferable 
that a line passing through the center of the heat generating surface of 
the heat generating element and perpendicular to the heat generating 
surface is close with a line passing through the center of the region of 
the gap between the free ends and perpendicular to the gap region, and it 
is further preferable that these lines are substantially overlapped. 
Further, it is preferable that a line passing through the center of the 
heat generating surface of the heat generating element and perpendicular 
to the heat generating surface, passes through the ejection outlet, and it 
is further preferable that the line and a line perpendicular to the 
ejection outlet through the center of the ejection outlet are overlapped. 
In the head having the one side movable portion as shown in FIG. 14B or the 
like and the opposing defect thereto, it is preferable that a line passing 
through the heat generating surface of the heat generating element and 
perpendicular to the heat generating surface, penetrate the one side 
movable portion. Additionally, it is preferable that a line passing 
through the center of the heat generating surface and vertical to the heat 
generating surface, penetrates the ejection outlet, and it is further 
preferable that the line and a line passing through the center of the 
ejection outlet and vertical to the ejection outlet are substantially 
overlapped. 
FIG. 21A-FIG. 21C is a schematic top plan view illustrating a configuration 
in which not less than three movable portions 6 are used for one bubble 
generation region, and FIG. 21A shows an example of three positions; FIG. 
21B shows an example of four positions, and show shows an example of six 
positions. The number of the movable portions 6 is not limited unless a 
problem arises in manufacturing. In any cases, the movable portions 6 are 
arranged in a radial fashion so that the pressure produced by the bubble 
is applied uniformly to the movable portions 6, and the fulcrum side is 
made arcuate to accomplish better operation and the durability. By the 
adjacent radial arrangement of the valve-like movable portion 6, large 
size droplets can be ejected with high efficiency. The plurality of 
movable portions 6 can be determined by one skilled in the art in 
accordance with the diameter of the droplet (dot size) to be ejected. 
As for the material of the separation wall including the movable portion, 
any material is usable if it has anti-solvent property against the bubble 
generation liquid and the ejection liquid, it has an elasticity suitable 
for operation as the movable portion, and it is suitable for formation of 
the fine slit. 
Preferable examples of the materials for the movable member include durable 
materials such as metal such as silver, nickel, gold, iron, titanium, 
aluminum, platinum, tantalum, stainless steel, phosphor bronze or the 
like, alloy thereof, or resin material having nitrile group such as 
acrylonitrile, butadiene, stylene or the like, resin material having amide 
group such as polyamide or the like, resin material having carboxyl such 
as polycarbonate or the like, resin material having aldehyde group such as 
polyacetal or the like, resin material having sulfone group such as 
polysulfone, resin material such as liquid crystal polymer or the like, or 
chemical compound thereof; or materials having durability against the ink, 
such as metal such as gold, tungsten, tantalum, nickel, stainless steel, 
titanium, alloy thereof, materials coated with such metal, resin material 
having amide group such as polyamide, resin material having aldehyde group 
such as polyacetal, resin material having ketone group such as 
polyetheretherketone, resin material having imide group such as polyimide, 
resin material having hydroxyl group such as phenolic resin, resin 
material having ethyl group such as polyethylene, resin material having 
alkyl group such as polypropylene, resin material having epoxy group such 
as epoxy resin material, resin material having amino group such as 
melamine resin material, resin material having methylol group such as 
xylene resin material, chemical compound thereof, ceramic material such as 
silicon dioxide or chemical compound thereof. 
Preferable examples of partition or division wall include resin material 
having high heat-resistive, high anti-solvent property and high molding 
property, more particularly recent engineering plastic resin materials 
such as polyethylene, polypropylene, polyamide, polyethylene 
terephthalate, melamine resin material, phenolic resin, epoxy resin 
material, polybutadiene, polyurethane, polyetheretherketone, polyether 
sulfone, polyallylate, polyimide, polysulfone, liquid crystal polymer 
(LCP), or chemical compound thereof, or metal such as silicon dioxide, 
silicon nitride, nickel, gold, stainless steel, alloy thereof, chemical 
compound thereof, or materials coated with titanium or gold. 
The thickness of the separation wall is determined depending on the used 
material and configuration from the standpoint of sufficient strength as 
the wall and sufficient operativity as the movable member, and generally, 
0.5 .mu.m-10 .mu.m approx. is desirable. 
As for width of the slit 35 for providing the movable member 31, when the 
bubble generation liquid and ejection liquid are different materials, and 
mixture of the liquids is to be avoided, the gap is determined so as to 
form a meniscus between the liquids, thus avoiding mixture therebetween. 
For example, when the bubble generation liquid has a viscosity about 2 cP, 
and the ejection liquid has a viscosity not less than 100 cP, 5 .mu.m 
approx. slit is enough to avoid the liquid mixture, but not more than 3 
.mu.m is desirable. 
In this invention, the movable member has a thickness of .mu.m order as 
preferable thickness. When a slit is formed in the movable member having a 
thickness of .mu.m order, and the slit has the width (W .mu.m) of the 
order of the thickness of the movable member, it is desirable to consider 
the variations in the manufacturing. 
When the thickness of the member opposed to the free end and/or lateral 
edge of the movable member formed by a slit, is equivalent to the 
thickness of the movable member, the relation between the slit width and 
the thickness is preferably as follows in consideration of the variation 
in the manufacturing to stably suppress the liquid mixture between the 
bubble generation liquid and the ejection liquid. When the bubble 
generation liquid has a viscosity not more than 3 cp, and a high viscous 
ink (5 cp, 10 cp or the like) is used as the ejection liquid, the mixture 
of the 2 liquids can be suppressed for a long term if W/t.ltoreq.1 is 
satisfied. 
The slit providing the "substantial sealing", preferably has several 
microns width, since the liquid mixture prevention is assured. 
When the ejection liquid and the bubble generation liquid are separated, 
the movable member functions as a partition therebetween. However, a small 
amount of the bubble generation liquid is mixed into the ejection liquid. 
In the case of liquid ejection for printing, the percentage of the mixing 
is practically of no problem, if the percentage is less than 20%. 
Therefore, the present invention covers the case where the mixture ratio of 
the bubble generation liquid of not more than 20%. 
In the foregoing embodiments, the maximum mixture ratio of the bubble 
generation liquid was 15% even when various viscosities are used. With the 
bubble generation liquid having the viscosity not more than 5 cps, the 
mixture ratio was 10% approx. at the maximum, although it is different if 
the driving frequency is different. The mixed liquid can be reduced by 
reducing the viscosity of the ejection liquid in the range below 20 cps 
(for example not more than 5%). 
(Ejection Liquid and Bubble Generation Liquid) 
When the ejection liquid and the bubble generation liquid are the same 
liquid, various liquid materials are usable, if it is not deteriorated by 
the heat imparted by the heat generating element; accumulated material is 
not easily deposited on the heat generating element; the state change of 
gassification and the condensation are reversible; and the liquid flow 
path, movable member or separation wall or the like are not deteriorated. 
For recording, the liquid used in a conventional bubble jet device as 
recording liquid, is also usable in this invention. 
On the other hand, eve if the ejection liquid and the bubble generation 
liquid are different liquid materials, the ejection liquid can be ejected 
by the displacement of the movable portion caused by the pressure produced 
by the bubble generation of the bubble generation liquid. Therefore, high 
viscosity liquid such as polyethylene glycol with which the bubble 
generation is not sufficient upon heat application, and therefore, the 
ejection power is not sufficient, can be ejected at high ejection 
efficiency and with high ejection pressure by supplying this liquid in the 
first liquid flow path and supplying, to the second liquid flow path as 
the bubble generation liquid, the good bubble generation liquid (a mixed 
liquid of ethanol and water at 4:6, having a viscosity of 1-2 cps approx., 
for example). 
The liquid easily influenced by heat can be ejected at high ejection 
efficiency and with high ejection pressure without thermal damage to such 
liquid, if such liquid is supplied to the first liquid flow path, and the 
liquid not easily influenced by the heat but having good bubble generation 
property, is supplied to the second liquid flow path. 
Various liquid materials are usable, if it is not deteriorated by the heat 
imparted by the heat generating element; accumulated material is not 
easily deposited on the heat generating element; the state change of 
gassification and the condensation are reversible; and the liquid flow 
path, movable member or separation wall or the like are not deteriorated. 
More particularly, examples of such liquids include methanol, ethanol, 
n-propanol, isopropanol, n-hexane, n-heptane, n-octane, toluene, xylene, 
methylene dichloride, trichlene, Freon TF, Freon BF, ethyl ether, dioxane, 
cyclohexane, methyl acetate, ethyl acetate, acetone, methyl ethyl ketone, 
water or the like or a mixture of them. 
As for the ejection liquid, various liquid is usable irrespective of 
thermal property or of the bubble generation property. The liquid having 
low bubble generation property, the liquid which is easily deteriorated or 
influenced by heat or the high viscous liquid, which are not easily 
ejected heretofore, can be ejected. However, it is desirable that the 
ejection, bubble generation or the operation of the movable portion is not 
obstructed by the ejection liquid per se or by the reaction with the 
bubble generation liquid. As for the reaction for the however, bubble 
generation movable portion of is usable. Other examples of ejection liquid 
include pharmaceuticals, perfume such as which is easily influenced by 
heat. 
The head shown in FIG. 1 was driven with voltage of 25 V and at 2.5 kHz 
using: 
The bubble generation liquid which was the above-described mixed liquid of 
ethanol and water; 
Ejection liquid which was dye ink (2 cps), pigment ink (15 cps), 
polyethylene glycol 200 or polyethylene glycol 600. 
As a result, satisfactory ejection was confirmed. 
Recording operations were also carried out using the following combination 
of the liquids for the bubble generation liquid and the ejection liquid. 
As a result, the liquid having a ten and several cps viscosity, which was 
unable to be ejected heretofore, was properly ejected, and even 150 cps 
liquid was properly ejected to provide high quality image. 
Bubble generation liquid 1: 
______________________________________ 
Ethanol 40 wt. % 
Water 60 wt. % 
______________________________________ 
Bubble generation liquid 2: 
______________________________________ 
Water 100 wt. % 
______________________________________ 
Bubble generation liquid 3: 
______________________________________ 
Isopropyl alcoholic 10 wt. % 
Water 90 wt. % 
______________________________________ 
Ejection liquid 1: 
(Pigment ink approx. 15 cp) 
______________________________________ 
Carbon black 5 wt. % 
Stylene-acrylate-acrylate ethyl 
1 wt. % 
copolymer resin material 
Dispersion material (oxide 140, 
weight average molecular weight) 
Mono-ethanol amine 0.25 wt. % 
Glyceline 69 wt. % 
Thiodiglycol 5 wt. % 
Ethanol 3 wt. % 
Water 16.75 wt. % 
______________________________________ 
Ejection liquid 2 (55 cp): 
______________________________________ 
Polyethylene glycol 200 
100 wt. % 
______________________________________ 
Ejection liquid 3 (150 cp): 
______________________________________ 
Polyethylene glycol 600 
100 wt. % 
______________________________________ 
Further, the use was made with the following liquid which is usable both 
for the ejection liquid and the bubble generation liquid, and the results 
were that high quality images were recorded because of high ink ejection 
speed. 
Dye ink (viscosity of 2 cps) 
______________________________________ 
C.I. hoodblack 2 dye 3 wt. % 
Diethylene glycol 10 wt. % 
Thiodiglycol 5 wt. % 
Ethanol 3 wt. % 
Water 77 wt. % 
______________________________________ 
In the case of the liquid which is not easily ejected heretofore, the 
ejection speed is low, and therefore, the variation of the ejecting 
directions is relatively larger with the result of variations of the shot 
positions of the droplets and variation of the ejection amounts due to the 
ejection instability, and therefore, the image quality is not very high. 
However, according to the embodiment, the generation of the bubble is 
stable and sufficient. Therefore, the shot accuracy of the liquid droplet 
is improved, and the ink ejection amount is stabilized, thus remarkably 
improving the recorded image quality. 
(Element Substrate) 
Hereinafter, the structure of the element substrate provided with heating 
members for applying heat to the liquid will be described. 
FIGS. 22A and 22B are sectional views of the element substrate of the 
liquid ejection head in accordance with the present invention. FIG. 22A 
depicts a portion of a head element substrate 1 provided with a protective 
film, which is on an electrothermal transducer comprising the heating 
member. FIG. 22B depicts a head element substrate 1 provided with no 
protective film. 
A layer of silicon oxide or silicon nitride is formed as a bottom layer 66 
on a substrate 67 of silicon or the like, for the purpose of insulation 
and heat accumulation. On the bottom layer 66, a 0.01-0.02 .mu.m thick 
heat generating resistor layer 65 (heat generating member 2) composed of 
hafnium boride (HfB.sub.2), tantalum nitride (TaN), tantalum aluminum 
(TaAl), or the like, and a 0.2-1.0 .mu.m thick patterned wiring electrode 
64 of aluminum or the like, are laminated. As voltage is applied to the 
heat generating resistor layer 65 through these two wiring electrodes 64, 
a current flows through the heat generating resistor layer 65 located 
between two electrodes 64, whereby heat is generated. 
In the case of the structure depicted in FIG. 22A, the 0.1-2.0 .mu.m thick 
protective layer 63 of the silicon oxide, silicon nitride, or the like is 
formed on the heat generating resistor layer, at least between the wiring 
electrodes 64. Further, a 0.1-0.6 .mu.m thick anti-cavitation layer of 
tantalum or the like is deposited on the protective layer 63, protecting 
at least the heat generating resistor layer 65 from various liquids such 
as ink. The reason why metallic material such as tantalum is used as the 
anti-cavitation layer 62 is that the pressure wave or the shock wave 
generated during the generation and collapse of the bubble is extremely 
powerful, being liable to drastically deteriorate the durability of the 
oxide film which is hard and brittle. 
FIG. 22B depicts a heat element substrate 1 without the protective layer 
62; the protective layer or the like is not mandatory. As for the heat 
generating resistor layer material which does not require the protective 
layer described above, metallic alloy material such as 
iridium-tantalum-aluminum alloy can be named. 
In other words, the structure of the heat generating member in accordance 
with the present invention may comprise the protective layer which is 
placed over the heat generating portion of the heat generating resistor 
layer, between the wiring electrodes, but this not mandatory. 
In this embodiment, the heat generating member is constituted of a heat 
generating resistor layer which generates heat in response to an electric 
signal. But, the present invention is not limited by this embodiment. The 
present invention is compatible with any heat generating member as long as 
it can generate bubbles in the bubble generation liquid sufficiently to 
eject the ejection liquid. For example, a photothermal transducer which 
generates heat as it receives light such as a laser beam, or a heating 
member comprising a heating portion which generates heat as it receives 
high frequency waves, may be employed. 
The element substrate 1 may integrally comprise functional elements such as 
transistors, diodes, latches, and shift registers, in addition to the 
aforementioned electrothermal transducers which contain the heat 
generating resistor layer 65 constituting the heat generating portion, and 
the wiring electrodes 64 for supplying the electric signals to the heat 
generating resistor layer 65. These functional elements are also formed 
through a semiconductor manufacturing process. 
FIG. 23 is a graph depicting the pattern of a driving signal applied to the 
heat generating member. The axis of abscissa presents the duration of the 
driving signal applied to the heat generating portion, and the axis of 
ordinates represents the voltage value of the driving signal. In order to 
eject the liquid by driving the heat generating portion of the 
electrothermal transducer arranged on the element substrate 1, a 
rectangular pulse as illustrated in FIG. 23 is applied to the heat 
generating resistor layer 65 through the wiring electrodes 64, causing the 
heat generating resistor layer 65 located between the wiring electrodes 
64, to rapidly generate heat. In each of the preceding embodiments, the 
driving signal applied to drive the heat generating member so that the 
liquid, that is, the ink, could be ejected from the ejection orifice 
through the aforementioned operation, had a voltage of 24 V, a pulse width 
of 7 .mu.sec, a current of 150 mA, and a frequency of 6 kH. However, the 
specifications of the driving signal are not limited to those described 
above; any driving signal is acceptable as long as it can properly 
generate bubbles in the bubble generation liquid. 
(Head Production Method) Next, a manufacturing method for the liquid 
ejection head in accordance with the present invention will be described. 
The manufacturing process for the liquid ejection head having the twin 
liquid flow paths is generally as follows. First, the walls of the second 
liquid flow path 4 are formed on the element substrate 1, and a separation 
wall 5 is placed on top of the walls. Then, a grooved member provided with 
the grooves or the like which will become the first liquid flow path 3 is 
placed on top of the separation walls 5. The separation wall 5 may be 
provided on the groove member, and in such a case, after the walls of the 
second liquid flow path 4 are formed, the grooved member with the 
separation walls 5 is bonded to the top surfaces of these walls. 
Next, the manufacturing method for the second liquid flow path 4 will be 
described. 
FIGS. 24A-24E are schematic sectional drawings depicting the steps of the 
liquid ejection head manufacturing method in the first embodiment of the 
present invention. 
Referring to FIG. 24A, the electrothermal transducer comprising a heating 
member 2 composed of hafnium boride, tantalum nitride, and the like is 
formed on the element substrate 1, that is, an individually plotted 
section of a silicon wafer, using manufacturing apparatuses similar to 
those employed for the semiconductor manufacturing process. Then, the 
surface of the element substrate 1 is cleansed to improve its adhesiveness 
to the photosensitive resin which is involved in the following step. In 
order to further improve the adhesiveness, the properties of the element 
substrate surface are modified with a combination of ultraviolet rays and 
ozone, or the like combination, and then is spin coated with, for example, 
a 1 wt. % ethyl alcohol solution of silane coupler A189 (product of NIPPON 
UNICA). 
Next, referring to FIG. 24B, a dry film Odyl SY-318 (product of Tokyo Ohka 
Kogyo Co., Ltd.), that is, an ultraviolet ray sensitive resin film DF, is 
laminated on the element substrate 1, the surface of which has been 
cleansed to improve the adhesiveness. 
Next, referring to FIG. 24C, a photomask PM is placed on the dry film DF. 
Ultraviolet rays are irradiated on the dry film DF covered with the 
photomask PM in a predetermined pattern, whereby the regions of the dry 
film DF, which are not shielded by the photomask PM, are exposed to the 
ultraviolet rays; these exposed regions are to become the walls of the 
second liquid flow path. This exposure process is carried out using an 
MPA-600 (product of Canon Inc.), whereby the rate of exposure is a 
pproximately 600 mJ/cm.sup.2. 
Next, referring to FIG. 24D, the dry film DF is developed using a developer 
BMRC-3 (product of Tokyo Ohka Kogyo Co., Ltd.), which is a mixture of 
xylene and butyl cellosolve acetate; the unexposed regions are dissolved, 
leaving the exposed and hardened regions as the walls of the second liquid 
flow path 4. Then, the residue remaining on the surface of the element 
substrate 1 is removed by treating the surface of the element substrate 1 
for approximately 90 seconds with an oxygen plasma ashing apparatus 
MAS-800 (product of Alcan-Tech Co., Ltd.). Next, the exposed regions are 
further irradiated with ultraviolet rays with a strength of 100 
mJ/cm.sup.2 for two hours at a temperature of 150.degree. C., being 
completely hardened. 
According to the above method, the second liquid flow path is uniformly and 
precisely formed on each of the heater boards on the silicon substrate. 
Next, a gold stud bump is formed on the electrical joint of the heater 
board using a bump bonder (product of Kushu Matsushita Electric Co., 
Ltd.). Thereafter, the silicon wafer is cut using a dicing machine 
AWD-4000 (product of Tokyo Seimitsu) equipped with a 0.05 mm thick diamond 
blade, separating each heater board 1. Next, a TAB tape and the heater 
board 1 are joined. Next, a compound member formed by bonding the grooved 
member 14a and the separation wall 5 is precisely positioned on the heater 
board 1 and bonded thereto. 
When the above method is used, not only can the liquid flow path be 
precisely formed, but it also can be positioned without becoming 
misaligned relative to the heater of the heater board. Since the grooved 
member 14a and the separation wall 5 are bonded together in a preceding 
step, the accuracy in the positional relationship between the first liquid 
flow path 3 and the flexible member 6 can be improved. The employment of 
these high precision manufacturing technologies makes it possible to 
produce a liquid ejection head capable of stable ejection, essential to 
the improvement of print quality. Further, these technologies allow a 
large number of heads to be formed on the wafer at the same time, making 
it possible to manufacture a large number of heads at low cost. 
In this embodiment, a dry film which can be hardened with ultraviolet rays 
was used to form the second liquid flow path 2, but a resin material, the 
absorption band of which is in the ultraviolet ray spectrum, in 
particular, near 248 nm, may be employed. In the latter case, the resin is 
hardened after being laminated, and then, the second liquid flow path is 
formed by directly removing the portions, which are to become the second 
liquid flow path, from the hardened resin using an excimer laser. 
FIGS. 25A-25E are schematic sectional drawings depicting the steps of the 
manufacturing method for the grooved member of the liquid ejection head in 
accordance with the present invention. 
Referring to FIG. 25A, in this embodiment, a 0.5 .mu.m thick resist 22 is 
placed on a stainless steel (SUS) substrate 21, in a predetermined pattern 
having the same pitch as the ejection orifice. In this embodiment, a 
resist having a diameter of 59 .mu.m is formed to yield an ejection 
orifice having a diameter of 30 .mu.m. 
Next, referring to FIG. 25B, a nickel layer 23 is grown on the SUS 
substrate 21 to a thickness of 15 .mu.m by electroplating. As for the 
plating solution, a mixture of sulfamic acid nickel, stress reducing agent 
Zero Ohru (product of World Metal Inc.), boric acid, anti-pitting agent 
NP-APS (product of World Metal Inc.), and nickel chloride, is used. As for 
the means for applying an electric field, an electrode is attached to the 
anode side, and the SUS substrate 21 on which pattering has been completed 
is attached to the cathode side. The temperature of the plating solution 
and the current density are kept at 50.degree. C. and 5 A/cm.sup.2, 
respectively. Thus, not only is the nickel layer allowed to grow in the 
thickness direction of the resist, but also in the diameter direction of 
the resist pattern, at the same speed. As a result, a preferable diameter 
is realized for the ejection orifice. 
Next, referring to FIG. 25C, a Dry Film Ordyl SY-318 (product of Tokyo Ohka 
Kogyo Co., Ltd.), that is, an ultraviolet sensitive resin film 24, is 
laminated on the nickel plated substrate 21. 
Then, referring to FIG. 25D, a photomask 25 is placed on the dry film 24, 
and the dry film 24 shielded with the photomask 25 in the predetermined 
pattern is irradiated with ultraviolet rays; the regions which will be 
left as the liquid path walls are irradiated with ultraviolet rays. This 
exposure process is carried out using an exposing apparatus MPA-600 
(product of Canon Inc.), wherein the rate of the exposure is approximately 
600 mJ/cm.sup.2. 
Next, referring to FIG. 25E, the dry film 24 is developed using a developer 
BMRC-3 (product of Tokyo Ohka Kogyo Co., Ltd.), which is a mixture of 
xylene and butyl cellosolve acetate; the unexposed regions are dissolved, 
leaving the regions hardened by the exposure as the walls of the liquid 
flow paths. The residue remaining on the surface of the substrate is 
removed by treating the surface of the substrate for approximately 90 
seconds with an oxygen plasma ashing apparatus MAS-800 (product of 
Alcan-Tech Co., Ltd.). Next, the exposed regions are further irradiated 
with ultraviolet rays with a strength of 100 mJ/cm.sup.2 for two hours at 
a temperature of 150.degree. C., being completely hardened. Thus, 15 .mu.m 
high walls are formed. Next, the nickel layer 24 is separated from the SUS 
substrate 21 by applying ultrasonic vibrations to the SUS substrate 21, 
yielding a grooved member in the predetermined form. 
In this embodiment, the liquid flow path was formed of resin material, but 
the grooved member may be formed of nickel alone. In the latter case, the 
regions of the dry film 24, which are not to become the liquid path walls, 
are removed in the step illustrated in FIG. 25D, and a nickel layer is 
accumulated by plating on the surface created by the removal of the "non 
wall" regions. Then, the resist is removed. When the surface of the nickel 
layer portion of the grooved member is placed with gold, the grooved 
member will be provided with much better solvent resistance. 
FIGS. 26A-26D are schematic sectional drawings depicting the steps of the 
liquid ejection head manufacturing method in the second embodiment of the 
present invention. 
Referring to FIG. 26A, in this embodiment, a 15 .mu.m thick resist 101 is 
placed on a stainless steel (SUS) substrate 100, in the pattern of the 
second liquid flow path. 
Next, referring to FIG. 26B, a nickel layer is grown on the exposed surface 
of the SUS substrate 100 by plating, to a thickness of 15 .mu.m. the same 
thickness as the thickness of the resist 101. As for the plating solution, 
a mixture of sulfamic acid nickel, stress reducing agent Zero Ohru 
(product of World Metal Inc.), boric acid, anti-pitting agent NP APS 
(product of World Metal Inc.), and nickel chloride, is used. As for the 
means for applying an electric field, an electrode is attached to the 
anode side, and the SUS substrate 21 on which pattering has been completed 
is attached to the cathode side. The temperature of the plating solution 
and the current density are kept at 50.degree. C. and 5 A/cm.sup.2, 
respectively. 
Next, referring to FIG. 26C, after the above described plating process is 
completed, the nickel layer 102 portion is separated from the SUS 
substrate by applying ultrasonic vibrations to the SUS substrate, 
completing the second liquid flow path with predetermined specifications. 
When the surface of the nickel layer portion is plated with gold after the 
nickel layer portion 102 is separated, the second liquid flow path will be 
provided with higher solvent resistance. 
In the meantime, the heater boards comprising electrothermal transducers 
are formed on a silicon wafer using a manufacturing apparatus similar to a 
semiconductor manufacturing apparatus. The wafer on which the heater 
boards have been formed is cut with a dicing machine, separating 
individual heater boards as described above. The separated heater board 1 
is bonded to a TAB tape to provide electrical wiring. Next, referring to 
FIG. 26D, the above described member comprising the second liquid flow 
path is precisely positioned on the heater board 1 which has been prepared 
as described above, and fixed thereto. During this positioning and fixing 
step, the strength with which the member comprising the second liquid flow 
path is fixed to the heater board 1 only has to be enough to prevent them 
from displacing from each other when the top plate is bonded thereon. This 
is because during the later steps, the top plate on which the separation 
walls have been fixed is placed on the thus assembled heater board, and 
all components are firmly fixed together using a pressing spring. 
In this embodiment, an ultraviolet ray hardening type adhesive (product of 
GRACE JAPAN; Amicon UV-300) is coated to the joint and is hardened with an 
ultraviolet radiation apparatus. The rate of exposure is 100 mJ/cm.sup.2, 
and the duration of exposure is approximately three seconds. 
According to the manufacturing method described in this embodiment, not 
only can the second liquid flow path be highly precisely produced, but 
also can be positioned without becoming misaligned relative to the heat 
generating member. In addition, the liquid flow path wall is formed of 
nickel. Therefore, it is possible to provide a highly reliable and highly 
alkali resistant head. 
FIGS. 27A-27D are schematic sectional drawings depicting the steps of the 
liquid ejection head manufacturing method in the third embodiment of the 
present invention. 
Referring to FIG. 27A, a resist 103 is coated on both surfaces of a 15 
.mu.m thick stainless steel (SUS) substrate 100 provided with alignment 
holes or marks 104. As for the resist, PMERP-AR900, a product of Tokyo 
Ohka Kogyo Co., Ltd., is used. 
Next, referring to FIG. 27B, the resist coated substrate 100 is exposed 
using an exposure apparatus MPA-600 (product of Canon Inc.), and then, the 
resist 103 is removed from the regions correspondent to the second liquid 
flow paths and the alignment holes 104. The rate of exposure is 800 
mJ/cm.sup.2. 
Next, referring to FIG. 27C, the SUS substrate 100 having a patterned 
resist 103 on both surfaces is immersed in an etching liquid (water 
solution of ferric chloride or cupric chloride), etching away the portions 
not covered by the resist 103, and then, the resist is removed. 
Next, referring to FIG. 27D, the etched SUS substrate 100 is positioned on 
the heater board 1, and is fixed thereto, completing a liquid ejection 
head comprising the second liquid flow path 4, in the same manner as the 
manufacturing method described in the preceding embodiment. 
According to this embodiment, not only can the second liquid flow path be 
formed with high precision but also can be positioned without becoming 
misaligned relative to the heater. In addition, the liquid flow path is 
formed of stainless steel. Therefore, it is possible to provide a highly 
reliable as well as highly alkali resistant liquid ejection head. 
According to the head manufacturing method described above, the walls of 
the second liquid flow path are formed on the element substrate in 
advance, making it possible to accurately position the electrothermal 
transducer and the second liquid flow path relative to each other. 
Further, the second liquid flow path can be formed on a large number of 
the element substrates collectively plotted on the substrate wafer before 
the substrate wafer is diced into separate pieces of element substrates. 
Therefore, a large number of liquid ejection heads can be provide at low 
cost. 
Further, in the liquid ejection head manufactured by the manufacturing 
method described in this embodiment, the heat generating member and the 
second liquid flow path are positioned relative to each other with high 
precision; therefore, the pressure from the bubble generation caused by 
the heat generation of the electrothermal transducer is effectively 
transmitted, making the head superior in ejection efficiency. 
(Liquid Ejection Head Cartridge) 
Next, a liquid ejection head cartridge in which the liquid ejection head in 
accordance with the preciding embodiments is mounted, will be concisely 
described. 
FIG. 28 is an exploded schematic view of the liquid ejection head cartridge 
comprising the aforementioned liquid ejection head. Essentially, the 
liquid ejection head cartridge comprises a liquid ejection head portion 
200 and a liquid container 80. 
The liquid ejection head portion 200 comprises an element substrate 1, a 
separation wall 30, a grooved member 50, a liquid container 90, a circuit 
board (TAB tape) 70 for supplying an electric signal, and the like. On the 
element substrate 1, a number of heat generating resistors for applying 
heat to the bubble generation liquid are aligned. Also on the element 
substrate 1, a number of functional elements for selectively driving these 
heat generating resistors are provided. A liquid flow path is formed 
between the element substrate 1 and the separation wall 30 comprising the 
flexible member, and the bubble generation liquid flows through this 
liquid flow path. The ejection liquid path (unillustrated), that is, the 
liquid path through which the liquid to be ejected flows, is formed as the 
separation wall 30, the grooved member 50, and the liquid delivery member 
80 are joined. Both liquids are supplied through the liquid delivery 
member 80, being routed behind the substrate 1. 
The liquid container 90 separately contains the liquid such as ink, and the 
bubble generation liquid for generating bubbles, both of which are 
delivered to the liquid ejection head. On the exterior surface of the 
liquid container 90, a positioning member 94 is provided for locating a 
connecting member which connects the liquid ejection head and the liquid 
container. The TAB tape 70, which is attached after the head portion is 
positioned on the liquid container 90, is fixed to the surface of the 
liquid container 90 using a double face adhesive tape. The ejection liquid 
is delivered to the first common liquid chamber by way of the ejection 
liquid delivery path 92 of the liquid container, the delivery path 84 of 
the connecting member, and the ejection liquid delivery path of the liquid 
delivery member 80, in this order. The bubble generation liquid is 
delivered to the second common liquid chamber by way of the delivery path 
93 of the liquid container, the supply path of the connecting member, and 
the bubble generation liquid path 82 of the liquid delivery member 80, in 
this order. 
In the foregoing, the description was given with reference to a combination 
of the liquid ejection head cartridge and the liquid container, which is 
capable of separately delivering or containing the bubble generation 
liquid and the ejection liquid when the bubble generation liquid and the 
ejection liquid are different. However, when the ejection liquid and the 
bubble generation liquid are the same, it is unnecessary to provide 
separate delivery paths and containers for the bubble generation liquid 
and the ejection liquid. 
Incidentally, the liquid container described above may be refilled after 
each liquid is consumed. In order to do so, it is preferable that the 
liquid container is provided with a liquid filling port. Further, the 
liquid ejection head and the liquid container may be inseparable or 
separable. 
FIG. 29 is a schematic illustration of a liquid ejecting device used with 
the above-described liquid ejecting head. In this embodiment, the ejection 
liquid is ink, and the apparatus is an ink ejection recording apparatus. 
The liquid ejecting device comprises a carriage HC to which the head 
cartridge comprising a liquid container portion 90 and liquid ejecting 
head portion 200 which are detachably connectable with each other, is 
mountable. The carriage HC is reciprocable in a direction of width of the 
recording material 150 such as a recording sheet or the like fed by a 
recording material transporting means. 
When a driving signal is supplied to the liquid ejecting means on the 
carriage from unshown driving signal supply means, the recording liquid is 
ejected to the recording material from the liquid ejecting head in 
response to the signal. 
The liquid ejecting apparatus of this embodiment comprises a motor 111 as a 
driving source for driving the recording material transporting means and 
the carriage, gears 112, 113 for transmitting the power from the driving 
source to the carriage, and carriage shaft 115 and so on. By the recording 
device and the liquid ejecting method using this recording device, good 
prints can be provided by ejecting the liquid to the various recording 
material. 
FIG. 30 is a block diagram for describing the general operation of an ink 
ejection recording apparatus which employs the liquid ejection method, and 
the liquid ejection head, in accordance with the present invention. 
The recording apparatus receives printing data in the form of a control 
signal from a host computer 300. The printing data is temporarily stored 
in an input interface 301 of the printing apparatus, and at the same time, 
is converted into processable data to be inputted to a CPU 302, which 
doubles as means for supplying a head driving signal. The CPU 302 
processes the aforementioned data inputted to the CPU 302, into printable 
data (image data), by processing them with the use of peripheral units 
such as RAMs 304 or the like, following control programs stored in an ROM 
303. 
Further, in order to record the image data onto an appropriate spot on a 
recording sheet, the CPU 302 generates driving data for driving a driving 
motor which moves the recording sheet and the recording head in 
synchronism with the image data. The image data and the motor driving data 
are transmitted to a head 200 and a driving motor 306 through a head 
driver 307 and a motor driver 305, respectively, which are controlled with 
the proper timings for forming an image. 
As for recording medium, to which liquid such as ink is adhered, and which 
is usable with a recording apparatus such as the one described above, the 
following can be listed; various sheets of paper; OHP sheets; plastic 
material used for forming compact disks, ornamental plates, or the like; 
fabric; metallic material such as aluminum, copper, or the like; leather 
material such as cow hide, pig hide, synthetic leather, or the like; 
lumber material such as solid wood, plywood, and the like; bamboo 
material; ceramic material such as tile; and material such as sponge which 
has a three dimensional structure. 
The aforementioned recording apparatus includes a printing apparatus for 
various sheets of paper or OHP sheet, a recording apparatus for plastic 
material such as plastic material used for forming a compact disk or the 
like, a recording apparatus for metallic plate or the like, a recording 
apparatus for leather material, a recording apparatus for lumber, a 
recording apparatus for ceramic material, a recording apparatus for three 
dimensional recording medium such as sponge or the like, a textile 
printing apparatus for recording images on fabric, and the like recording 
apparatuses. 
As for the liquid to be used with these liquid ejection apparatuses, any 
liquid is usable as long as it is compatible with the employed recording 
medium, and the recording conditions. 
(Recording System) 
Next, an exemplary ink jet recording system will be described, which 
records images on recording medium, using, as the recording head, the 
liquid ejection head in accordance with the present invention. 
FIG. 31 is a schematic perspective view of an ink jet recording system 
employing the aforementioned liquid ejection head 201 in accordance with 
the present invention, and depicts its general structure. The liquid 
ejection head in this embodiment is a full-line type head, which comprises 
plural ejection orifices aligned with a density of 360 dpi so as to cover 
the entire recordable range of the recording medium 150. It comprises four 
heads, which are correspondent to four colors; yellow (Y), magenta (M), 
cyan (C) and black (Bk). These four heads are fixedly supported by a 
holder 1202, in parallel to each other and with predetermined intervals. 
These heads are driven in response to the signals supplied from a head 
driver 307, which constitutes means for supplying a driving signal to each 
head. 
Each of the four color inks (Y, M, C and Bk) is supplied to a correspondent 
head from an ink container 204a, 204b, 205c or 204d. A reference numeral 
204e designates a bubble generation liquid container from which the bubble 
generation liquid is delivered to each head. 
Below each head, a head cap 203a, 203b, 203c or 203d is disposed, which 
contains an ink absorbing member composed of sponge or the like. They 
cover the ejection orifices of the corresponding heads, protecting the 
heads, and also maintaining the head performance, during a non-recording 
period. 
A reference numeral 206 designates a conveyer belt, which constitutes means 
for conveying the various recording medium such as those described in the 
preceding embodiments. The conveyer belt 206 is routed through a 
predetermined path by various rollers, and is driven by a driver roller 
connected to a motor driver 305. 
The ink jet recording system in this embodiment comprises a pre-printing 
processing apparatus 251 and a postprinting processing apparatus 252, 
which are disposed on the upstream and downstream sides, respectively, of 
the ink jet recording apparatus, along the recording medium conveyance 
path. These processing apparatuses 251 and 252 process the recording 
medium in various manners before or after recording is made, respectively. 
The pre-printing process and the postprinting process vary depending on the 
type of recording medium, or the type of ink. For example, when recording 
medium composed of metallic material, plastic material, ceramic material 
or the like is employed, the recording medium is exposed to ultra-violet 
rays and ozone before printing, activating its surface. 
In a recording material tending to acquire electric charge, such as plastic 
resin material, the dust tends to deposit on the surface by static 
electricity, the dust may impede the desired recording. In such a case, 
the use is made with ionizer to remove the static charge of the recording 
material, thus removing the dust from the recording material. When a 
textile is a recording material, from the standpoint of feathering 
prevention and improvement of fixing or the like, a pre-processing may be 
effected wherein alkali property substance, water soluble property 
substance, composition polymeric, water soluble property metal salt, urea, 
or thiourea is applied to the textile. The pre-processing is not limited 
to this, and it may be the one to provide the recording material with the 
proper temperature. 
On the other hand, the post-processing is a process for imparting, to the 
recording material having received the ink, a heat treatment, ultraviolet 
radiation projection to promote the fixing of the ink, or a cleaning for 
removing the process material used for the pre-treatment and remaining 
because of no reaction. 
In this embodiment, the head is a full line head, but the present invention 
is of course applicable to a serial type wherein the head is moved along a 
width of the recording material. 
(Head Kit) 
Hereinafter, a head kit will be described, which comprises the liquid 
ejection head in accordance with the present invention. FIG. 32 is a 
schematic view of such a head kit. This head kit is in the form of a head 
kit package 501, and contains: a head 510 in accordance with the present 
invention, which comprises an ink ejection section 511 for ejecting ink; 
an ink container 510, that is, a liquid container which is separable, or 
nonseparable, from the head; and ink filling means 530, which holds the 
ink to be filled into the ink container 520. 
After the ink in the ink container 520 is completely depleted, the tip 530 
(in the form of a hypodermic needle or the like) of the ink filling means 
is inserted into an air vent 521 of the ink container, the junction 
between the ink container and the head, or a hole drilled through the ink 
container wall, and the ink within the ink filling means is filled into 
the ink container through this tip 531. 
When the liquid ejection head, the ink container, the ink filling means, 
and the like are available in the form of a kit contained in the kit 
package, the ink can be easily filled into the ink depleted ink container 
as described above; therefore, recording can be quickly restarted. 
In this embodiment, the head kit contains the ink filling means. However, 
it is not mandatory for the head kit to contain the ink filling means; the 
kit may contain an exchangeable type ink container filled with the ink, 
and a head. 
Even though FIG. 32 illustrates only the ink filling means for filling the 
printing ink into the ink container, the head kit may contain means for 
filling the bubble generation liquid into the bubble generation liquid 
container, in addition to the printing ink refilling means. 
While the invention has been described with reference to the structures 
disclosed herein, it is not confined to the details set forth and this 
application is intended to cover such modifications or changes as may come 
within the purposes of the improvements or the scope of the following 
claims.