Method and apparatus for manufacturing ink jet head

Abstract: The present invention provides an ink jet head manufacturing method including a pressurizing step for forming liquid passages (5) communicating with discharge openings for discharging ink, by pressurizing to bond a base member (1) and a top member (2) together via wall members (3) defining the liquid passages, substantially except for areas where the liquid passages are formed. The present invention further provides an apparatus for carrying out such ink jet head manufacturing method.

Description: The present invention relates to a method for manufacturing an ink jet head for forming liquid droplets by discharging recording liquid by utilizing an ink jet recording technique, and more particularly, it relates to a method and apparatus for bonding a top member to a base member via wall members for defining ink passages therein. Related Background Art As shown in Fig. 4, in an ink jet head used with ink jet recording systems (liquid jet recording systems), a base member is formed by arranging a predetermined number (three in Fig. 4) of energy generators (for example, electrothermal conversion members) 32 for generating energy used to discharge ink on a support plate 31 made of silicone and the like, and a pattern corresponding to discharge openings 33, ink passages 34 and a common ink chamber 35 is formed by the lithographic technique to obtain such discharge openings, ink passages and ink chamber, and a top member 36 is covered on the formed pattern, thus manufacturing the ink jet head. Conventionally, in order to bond the top member 36 to the base member, an adhesive having capable of being softened by the illumination of ultraviolet ray (UV) was coated on one surface of the top member 36, the top member was positioned with respect to the base member on which the pattern was formed, the top and base members were abutted against each other with an appropriate pressure, and then the adhesive was cured by illuminating the ultraviolet ray thereon, thus adhering both members to each other. The pressure for bonding these members to each other can be obtained by rollers (Fig. 5) or a press for applying the pressure to the parallel members (Fig. 6). In the case where the pressure is obtained by the rollers, as shown in Fig. 5, the top member 36 and the base member 43 with the interposition of wall members 42 defining ink passages communicating with discharge openings are passed between and pressed by pressure rollers 41, 41' rotated in directions shown by the arrows A. Incidentally, the reference numeral 45 denotes an adhesive layer for adhering the wall members 42 to the top member 36; and 46 denotes a work support on which the base member 43 and the top member 36 are rested and which can be used at need. When such rollers are used to pressurize the members against each other, it is feared that the following problems arise: (1) When the base member and the top member (which constitutes a "work") positioned with respect to each other are inserted between the rollers, if one of the members is contacted with the roller, the discrepancy in the relative position between the base member and the top member will occur. (2) If the hard rollers are used, the penetrating amount of the wall members into the adhesive layer will be non-uniform or uneven due to the dispersion in the thickness accuracy of the work and/or work support, which results in the dispersion in positions of the discharge openings in height direction. Thus, the dimensions of the discharge openings do not become constant or uniform. Further, if any hard foreign matter exists between the adhesive layer and the wall member and/or top member, the dispersion in the dimensions of the discharge openings will be further increased. (3) If the rollers covered by a soft rubber layers are used, since the surfaces of the rollers are soft, as shown in Fig 7, the dispersion (as shown X, Y in Fig. 7) in the penetrating amount of the wall members 42 into the adhesive layer 45 will occur due to the deformation of the rollers, with the result that the dimensions of the discharge openings do not become constant or uniform. On the other hand, when the press is used to pressurize the members against each other by pressing the work rested on a press platform 47 by a pressure member 48 as shown in Fig. 6, it is feared that the following problems arise: (4) Due to the dispersion in the thickness accuracy of the work and/or work support 46, unevenness in the press surfaces, and/or unparallelism between the upper and lower surfaces of the press, the same problem as mentioned in the above Item (2) occurs. (5) If an elastic flat plate 49 is interposed between the pressure member 48 and the top member 36, as shown in Fig. 8, since the pressure value per a unit area is varied between regions where there are greater portions (wall members and the like) to be adhered and regions where there are less portions to be adhered, the dispersion in the penetrating amount into the adhesive layer will occur, with the result that the dimensions of the discharge openings do not become constant or uniform. (6) If the parallelism of the press is insufficient, since the pressure member of the press initially contacts with the top member locally, the relative position between the top member and the base member will be changed during the operation of the press. Further, after the adhesion, the adhered work is dismounted from the press and the adhesive layer is cured. In this case, it is feared that the adhesive layer is separated unless the temperature of the adhesive is lowered to a room temperature level to increase the viscosity of the adhesive during the dismounting of the work and the ultraviolet rays are illuminated onto the adhesive layer immediately after the dismounting of the work, because, due to the fact that the viscosity of the adhesive is reduced to facilitate the adhesion by increasing the temperature during the adhesion process, if the coefficient of thermal expansion of the base member (for example, made of silicone wafer) differs from that of the top member (for example, made of glass), the camber will occur during the cooling of the members, thus causing the separation of the adhesive layer. SUMMARY OF THE INVENTION The present invention aims to eliminate the aforementioned conventional drawbacks, and an object of the present invention is to provide a method and apparatus for manufacturing an ink jet head. This object is solved by the features of claims 1 and 23. According to an advantageous preferred embodiment of the present invention, the following features are provided: (a) The top member is temporarily adhered to the base member at plural peripheral points thereof with two liquid component instantaneous adhesive in order to prevent the discrepancy in the relative position between the top and base members in subsequent processes or steps after they are bonded together. (b) A heating/cooling means is provided in a press, so that the adhesive is heated during the bonding to reduce the viscosity of the adhesive, thereby facilitating the bonding between the top member and the base member and that the adhesive is cooled after the bonding to increase the viscosity of the adhesive, thereby effectively preventing the camber of the member(s) due to the difference in the coefficient of thermal expansion between the members and the resulting separation therebetween. (c) Recessed portions corresponding to the wall members defining the ink passages and wall portions defining common ink chambers are formed in a pressure member of the press so that only the wall members and the wall portions are pressurized by the press during the bonding between the top member and the base member. That is to say, if there is no such recessed portions, thinner wall portions of the top member directly opposing the ink chambers are also pressurized by the pressure member, with the result that the top member is distorted as shown in Fig. 9. The distortion of the top member will cause the difference in the penetrating amount of the wall members defining the ink passages and the wall portions defining the ink chambers into the adhesive. Further, by interposing a thin elastic layer such as a rubber layer between the work and the pressure member of the press, the uneven pressure generated due to the dispersion in the thickness of the work and the pressure member and/or the parallelism between the work and the pressure member and acting on the work can be compensated. (d) In order to prevent the top member and the base member after the bonding therebetween, the work is cooled by the above-mentioned cooling means while they are being pressurized after adhesion, thus releasing the stress due to the thermal expansion of the members. Thereafter, the adhesive layer is cured by illuminating the ultraviolet rays thereon. To this end, the pressure member and at least one of the base member and the top member are made of UV permeable material. More particularly, the present invention includes a pressurizing step for forming ink passages communicating with discharge openings for discharging ink by pressurizing and bonding the base member and the top member together substantially except for regions where the ink passages are formed, during the bonding between the base member and the top member via the wall members defining the ink passages. Further, the present invention has the following features: that is, recessed portions corresponding to the regions where the ink passages are formed in the pressure member for performing the pressurization; the pressurization is effected via an elastic thin film or layer disposed between the pressure member and an element to be pressurized; the elastic thin layer has the hardness of 40 - 85 degrees obtained by an A-type hardness tester of K6301 spring type in the Japanese Industrial Standard (JIS), and has a thickness of 0.2 - 1 mm; the bonding is effected by the adhesive layer capable of being cured by the illumination of the ultraviolet rays and disposed between the top member and the wall members; such ultraviolet ray cured adhesive layer has a thickness of 1 - 5 µm; the pressure member for performing the pressurization is permeable to the ultraviolet rays; after the pressurization, a curing step for curing the ultraviolet ray cured adhesive layer by illuminating the ultraviolet ray thereon is included; both the base member and the top member are plate-shaped; the pressurization is effected while heating; the heating is effected before the pressurization; before the pressurization step, a temporary adhesion step for temporarily adhering the top member to the wall members defining the ink passages at plural points around the ink passages is included; the temporary adhesion is effected by using a two liquid component elastic adhesive; a cooling step for cooling the element to be pressurized while pressurizing such element is included; the ink passages include a plurality of ink paths communicating with corresponding discharge openings and with common ink chambers, and recesses corresponding to the ink chambers are formed in an inner wall of the top member; energy generators for generating energy utilized to discharge the ink from the discharge openings are disposed in the ink passages; the energy generators comprise electrothermal conversion members for generating thermal energy as the aforementioned energy; a plurality of discharge openings are arranged along a whole width of a recording sheet on which an image is recorded by the ink discharged from the discharge openings; and a separating step for separating the manufactured ink head assembly into individual ink jet head units after the pressurization step. According to the present invention an embodiment of an apparatus for manufacturing an ink jet head, comprises: a pressure member for forming ink passages communicating with discharge openings for discharging ink, by bonding a top member to a base member, substantially except for regions where the ink passages are formed, via wall members for defining such ink passages. The apparatus is characterized in that recessed portions corresponding to the regions where the ink passages are formed in the pressure member, and it includes a temperature adjusting means for adjusting the temperatures of the top member and the base member via the pressure member, and that the bonding between the top member and the base member is effected with the interposition of the ultraviolet ray cured adhesive layer and the pressure member is permeable to the ultraviolet rays, and an ultraviolet ray lighting means for illuminating the ultraviolet rays onto the ultraviolet ray curable adhesive via the pressure member is provided. BRIEF DESCRIPTION OF THE DRAWINGS Figs. 1A to 1C are explanatory views showing an example of manufacturing steps of an ink jet head manufacturing method according to the present invention; Figs. 2A to 2C is a partial view showing a condition that a pressurizing tool used in the manufacturing method of the present invention is positioned with respect to a work, Fig. 2B-A is a partial plan view of the pressurizing tool, Fig. 2B-B is a sectional view taken along the line Z - Z in Fig. 2B-A, and Fig. 2C is a partial plan view of an alteration of a pressurizing tool used in the manufacturing method of the present invention; Figs. 3A and 3B are partial sectional views showing a condition that a top member and a side wall pattern are bonded to each other; Fig. 4 is a perspective view of an ink jet head; Fig. 5 is an elevational sectional view showing an example of a conventional method for bonding a top member to a base member including a side wall pattern; Fig. 6 is an elevational sectional view showing an example of another conventional method for bonding a top member to a base member including a side wall pattern; Fig. 7 is an elevational sectional view showing a condition that a top member and a base member are bonded together by using soft rollers; Fig. 8 is an elevational sectional view showing a condition that a top member and a base member are bonded together by pressurization with the interposition of a flat rubber layer; Fig. 9 is a partial elevational sectional view showing a condition that a top member and a base member are bonded together by pressurization by means or a pressurizing tool having no recessed portions; and Fig. 10 is a perspective view of a recording system incorporating an ink jet head according to the present invention therein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be explained in connection with embodiment thereof with reference to the accompanying drawings. Figs. 1A to 1C show steps for bonding a top member to a base member on which wall members defining ink passages are formed, in the ink jet head manufacturing method according to the present invention. Positioning, Fig. 1A shows a positioning step for positioning a base member 1 and a top member 2 with respect to each other before they are bonded together. That is to say, the base member 1 is made of silicone and the like. Energy generators (not shown), and wall members 3 for defining ink passages and wall portions 4 for defining ink chamber which are made of photosensitive resin are formed on the base member 1. The photosensitive resins may be any one of resins disclosed in U.S. Patent 4,417,251. The top member 2 is made of material permeable to ultraviolet rays (UV) such as glass and is provided with recesses 6 in correspondence to positions of the ink chambers, for increasing a heights of the ink chambers higher than those of the ink passages 5. An UV curable adhesive layer (i.e., adhesive layer capable of being cured by the ultraviolet rays) 7 is coated on the top member 2 except for the recesses 6. For example, by using a roll coater, the adhesive layer 7 can be selectively formed on the top member except for the recesses 6. The adhesive used to form the adhesive layer 7 is preferably an UV curable adhesive which can easily cured for a short time by illuminating the ultraviolet rays thereon after the bonding between the top member and the base member. Preferably, the adhesive material is NOPCOCURE CPA-4 or NOPCOCURE CPA-5 manufactured by SANNOPCO Co., Ltd., which has urethane acrylester as a main component. Other light-curable resins may be used as the adhesive for this purpose. A thickness of the adhesive layer 7 is preferably in a range of 1 - 5 µm. If the adhesive layer is thinner than 1 µm, when the thickness of the wall members is uneven, it is feared that non-adhered areas are created after the bonding. To the contrary, if the adhesive layer is thicker than 5 µm, it is feared that, during the bonding, a part of the adhesive pushed out of the wall members 3 enters (penetrates) into the ink passages 5, thus reducing the cross-sectional areas of the discharge openings and the ink passages 5. The dispersion in such cross-sectional areas depends upon an amount of the adhesive pushed out of the wall members 3, thus making the control of the cross-sectional areas of the ink passages and the like difficult. Therefore, more preferably, the thickness of the adhesive layer 7 is in a range of 1.5 - 3 µm. Incidentally, the reference numeral 8 denotes first liquid droplets of a two liquid component instantaneous adhesive which is instantaneously cured by mixing a first liquid with a second liquid. These first liquid droplets are deposited on either or both of the base member 1 and the top member 2 to be bonded together, at a plural paint along a peripheral zone of the member. Such adhesive is preferably a two liquid component instantaneous adhesive which is not cured even if it takes a relatively long time to position the base and top members relative to each other (described later) and which can be instantaneously cured at need to minimize a waiting time (curing time, heating time and the like) to a next process or step. However, since, if adhesives of rubber group are used, it is feared that the discrepancy in the relative position between the top and base members occurs after the adhesive is cured, and if adhesives are too hard after curing, it is feared that clack and/or separation of the adhesive occurs even due to the small shock and the like. Thus, such adhesives are not acceptable. It was found that an clastic instantaneously adhesive "PEG-α" manufactured by CEMEDINE Co., Ltd. is excellent in view of adherence and hardness. In this process, the base member 1 having the wall member 3 and the like, and the top member 2 are overlapped as shown in Fig. 1A so that the wall members 3 and the recesses 6 of the top member 2 are opposed to each other, thereby positioning the wall members 3, wall portions 4 and the recesses 6 of the top member 2. The positioning between these portions can be ascertained by an operator's eye or any microscope. Temporary Adhesion In this process, the work positioned in the manner as mentioned above is temporarily adhered (temporarily bonded) to prevent the positioned members from being displaced in the subsequent processes. That is to say, as shown in Fig. 1B, second liquid droplets 9 of the second liquid of the above-mentioned two liquid component instantaneous adhesive are applied onto the first liquid droplets 8 deposited on the work so positioned, with the result that the adhesive is instantaneously cured by mixing these liquid droplets, thus temporarily bonding the base member 1 and the top member 2 together. The second liquid may be applied or poured by using a micro-cylinder and the like. Since the height of the wall members 3 is in the order of 20 - 40 µm, the second liquid can quickly flow onto the first liquid by capillary phenomenon, thus curing the adhesive quickly. Incidentally, the bonding may be effected at two or more points to ensure the bonding effect. Positioning Before Bonding As shown in Fig. 1C, the work temporarily bonded is rested on a press platform 11 of a bonding machine, together with or without a work support 10. Then, a thin elastic film or layer 12 made of semi-transparent silicone rubber and the like is rested on the work, and further, a pressure member 13 made of UV permeable material such as quartz, glass or the like is overlapped on the elastic layer 13. Preferably, the thin elastic layer has the hardness of 40 - 85 degrees obtained by an A-type hardness tester of K6301 spring type, and a thickness of 0.2 - 1 mm. As shown in Fig. 2B, recesses 14 are formed in a lower surface of the pressure member 13 so that only the wall members 3 and the ink chamber defining wall portions 4 of the work can be pressurized substantially uniformly with the aid of the thin elastic film during the pressurizing process. Fig. 2A is a plan view showing a condition that the recesses 14 of the pressure member 14, and the wall members 3 and ink chamber defining wall portions 4 of the base member 1 are positioned with respect to each other. Incidentally, the reference numeral 15 denotes wire bonding pad portions; and 16 denotes separating lines along which the discharge unit is divided. If there are no recesses 14, as shown in Fig. 8, the uneven bonding will frequently occur due to the deformation of the top member 36. The positioning can be effected while ascertaining the positions of the elements by the operator's eyes since the top member is transparent. However, when it is difficult to correctly position the elements because of the interposition of the thin elastic layer of silicone rubber, the positioning may be effected by abutting the work and the pressure member against an end wall of the press. Incidentally, alternatively, the pressure member 13 may be constituted as shown in Fig. 2C. In Fig. 2C, the pressure member 13 is provided with recesses 14a corresponding to areas where the ink passages are formed, as well as the above-mentioned recesses 14 corresponding to areas where the ink chambers are formed. Bonding After the work and the pressure member 13 are positioned in place, the work is heated. The work may be heated by a heater incorporated into the press or by an infrared ray heater from above. The upper heater is not inebitable, but, the work can be heated from below. The heating temperature is preferably 50 - 150°C, and most preferably 80 - 120°C for the adhesive of the layer 7. After the heating, the top member and the base member are bonded together by pressurizing the work in a direction shown by the arrow P in Fig. 1C. Incidentally, the heating may be effected simultaneously with the pressurizing. Further, although the pressure is varied in accordance with the heating temperature, in the above temperature range, it was found that the good bonding condition (Fig. 3A) could be obtained with the pressure of 0.5 - 10 kg/cm 2 . Qualitatively, when the temperature of the adhesive layer 7 is high, the pressure may be relatively low; whereas, when the temperature of the adhesive layer is low, high pressure is required. If the temperature of the adhesive is too low, the strength of adhesion at the interface between the adhesive layer and the wall members 3 becomes weaker, thus causing the separation after the curing of the adhesive. On the other hand, if the temperature of the adhesive is too high, even when the work is pressurized with low pressure, the adhesive between the top member 2 and the wall members 3 will be all pushed out from the interfaces therebetween, with the result that there is no adhesive between the top member 2 and the wall members 3 and thus the bonding is sometimes effected only between the top member and side surfaces of the wall members. In such a case, the adhesion strength is relatively weak, and, as shown in Fig. 3B, the greater adhesive material 17 penetrates into the ink passages, thus making the discharge openings smaller and/or uneven. A pressurizing mechanism for performing the pressurization may be so designed that the work is pressurized from below, because an UV lamp for illuminating the ultraviolet rays from above must be arranged above the press as will be described later. Further, since, when the moving parts are disposed below the work, the latter can be prevented from being smudged by dirt and the like, it is advantageous to arrange the pressurizing mechanism below the work in this respect. UV Cure After the bonding, the work is cooled. Such cooling can be effected by using water cool pipes (not shown) embedded in the press platform 11 shown in Fig. 1C. Since the base member and the top member are bonded together under the high temperature, when the temperature of the work is returned to the room temperature, there arises the stress between these members due to the difference in the coefficient of thermal expansion (for example, between the base member made of silicone wafer and the top member made of glass). To minimize such stress, the work is cooled to or near the room temperature before the adhesive layer 7 is cured, thus eliminating the stress due to the change in the temperature. Then, the adhesive layer 7 is cured by illuminating the ultraviolet rays thereon. The UV lamp is arranged above the work so that the ultraviolet rays can pass through the pressure member 13, thin elastic layer (silicone rubber) 12 and the top member 2 to core the adhesive layer 7. However, since the energy loss of the ultraviolet rays is great while passing through the silicone rubber and thus the large-sized UV lamp is required to cure the adhesive completely, it is desirable to solidify the adhesive to an extent that the adhesive cannot flow. After the adhesive is cured, the pressurization is released. In this way, since the adhesive is cured while being pressurized, it is possible to prevent the separation between the bonded parts and to achieve the stable bonding condition. Lastly, after the work (the adhesive therein) is cured by heat and ultraviolet rays, the finished work (assembly) is cut along the separating lines 16 to obtain individual discharge elements. In this way, it is possible to provide an ink jet head as shown in Fig. 4. The present invention is particularly effective to a recording head and recording apparatus for discharging ink by utilizing thermal energy, among liquid jet recording systems (ink jet recording systems). It is preferable to employ the typical structure and the principle of structures disclosed in, for example, U.S.P. No. 4,723,129 and U.S.P. No. 4,740,796. This system can be adopted in a so-called "On-Demand" type and "Continuous" type structures. In this system, an electrothermal conversion member disposed to align to a sheet or a liquid passage in which liquid (ink) is held is supplied with at least one drive signal which corresponds to information to be recorded and which enables the temperature of the electrothermal conversion member to be raised higher than a nuclear boiling point, so that thermal energy is generated in the electrothermal conversion member and film boiling is caused to take place on the surface of the recording head which is heated. As a result, bubbles can be respectively formed in liquid (ink) in response to the drive signals. Due to the enlargement and contraction of the bubble, liquid (ink) is discharged through the discharge port, so that at least one droplet is formed. In a case where the aforesaid drive signal is made to be a pulse signal, a further satisfactory effect can be obtained in that the bubble can immediately and properly be enlarged/contract and liquid (ink) can be discharged while exhibiting excellent responsibility. It is preferable to employ a drive signal of the pulse signal type disclosed in U.S.P. 4,463,359 and U.S.P. 4,345,262. Furthermore, in a case where conditions for determining the temperature rise ratio on the aforesaid heated surface disclosed in U.S.P. No. 4,313,124 are adopted, a further excellent recording operation can be performed. In addition to the structure (a linear liquid passage or a perpendicular liquid passage) of the recording head formed by combining the discharge ports, the liquid passage and the electrothermal conversion member as disclosed in the aforesaid specifications, a structure disclosed in U.S.P. 4,558,333 and U.S.P. 4,459,600 in which the heated portion is disposed in a bent portion is included in the scope of the present invention. Furthermore, the present invention can effectively be embodied in a structure in which a common slit is made to be the discharge portion of a plurality of electrothermal conversion members and which is disclosed in Japanese Patent Appln. Laid-Open No. 59-123670 and a structure in which an opening for absorbing thermal energy pressure wave is formed to align to the discharge port and which is disclosed in Japanese Patent Appln. Laid-Open No. 59-138461. A full line type recording head having a length which corresponds to the width of the maximum recording medium which can be recorded by the recording apparatus may be a structure capable of realizing the aforesaid length and formed by combining a plurality of recording heads as disclosed in the aforesaid specifications or a structure formed by an integrally formed recording head. The present invention will enable the aforesaid effects to be exhibited further effectively. In addition, the present invention can also be effectively adapted to a structure having an interchangeable chip type recording head which can be electrically connected to the body of the apparatus or to which ink can be supplied from the body of the apparatus when it is mounted on the body of the apparatus or a cartridge type recording head integrally formed to the recording head. It is preferable to additionally provide the recording bead recovery means and an auxiliary means of the recording apparatus according to the present invention because the effect of the present invention can further be stabled. Specifically, an effect can be obtained in that the recording operation can be stably performed by providing a recording head capping means, a cleaning means, a pressurizing or sucking means, an electrothermal conversion member of another heating device or an auxiliary heating means formed by combining the aforesaid elements and by performing a previous discharge mode in which a discharge is performed individually from the recording operation. Furthermore, the recording mode of the recording apparatus may be a recording mode for recording only main color such as black and a structure may be that formed by integrally forming recording heads or a structure formed by combining a plurality of recording heads. The present invention can significantly effectively be adapted to an apparatus having a recording head of a plurality of colors or at least one full color head arranged to mix colors. Although the aforesaid embodiments use liquid ink, ink which is solid, at room temperature or ink which is softened at room temperature can be used. In the aforesaid ink jet apparatus, the temperature of ink is usually controlled in a range from 30°C to 70°C to make the viscosity of ink to be in a stable discharge range and thereby ink which is liquefied in response to a record signal supplied may be used. Furthermore, ink the temperature rise of which is prevented by positively using the temperature rise due to the thermal energy as energy of state change from the solid state to the liquid state of ink or ink which is solidified when it is allowed to stand in order to prevent the evaporation or ink may be used. That is, ink which is liquefied by thermal energy such as ink liquefied by thermal energy supplied in response to the record signal and discharged as ink droplet or ink which is solidified when it teaches the recording medium can be employed in the present invention. In this case, ink may be, in the form of liquid or solid, held by a recess of a porous sheet or a through hole as disclosed in Japanese Patent Appln. Laid-Open No. 54-56847 or Japanese Patent Appln. Laid-Open No. 60-71260 and disposed to confront the electrothermal conversion member. It is most preferable that ink be discharged by the aforesaid film boiling method. Fig. 10 is a perspective view showing an example of an ink jet recording apparatus (IJRA) incorporating therein a recording head obtained by the present invention as an ink jet head cartridge (IJC). In Fig. 10, the reference numeral 20 denotes an ink jet head cartrdige (IJC) having a group of nozzles for discharging ink droplets toward a recording surface of a recording sheet fed onto a platen 24. The reference numeral 27 denotes a carriage for carrying the ink jet head cartridge 20. The carriage 27 is connected to a drive belt 18 for transmitting a drive force from a drive motor 28 to the carriage and can be reciprcocally shifted across the whole width of the ink jet head cartridge 20 along two parallel guide shafts 19A, 19B. The reference numeral 26 denotes a head recovery device disposed in the vicinity of one end of the moving path of the ink jet head cartridge 20 (for example, a home position). The head recovery device 26 is driven by a driving force of a motor 22 via transmitting mechanism 23 so that the ink jet head cartridge 20 is capped by a cap portion 26A of the head recovery device 26. In response to the capping of the ink jet head cartridge 20 by means of the cap portion, the ink is sucked by an appropriate suction means provided in the head recovery device 26 or the ink is forcibly supplied by an appropriate pressure means provided in an ink supply path, so that the ink is forcibly discharged from the discharge openings, thus removing the viscous ink from the nozzles (discharge recovery treatment). Further, after the recording operation, by capping the ink jet head cartridge 20, the latter can be protected. The reference numeral 30 denotes a blade as a wiping member made of silicone rubber and arranged at a side of the head recovery device 26. The blade 30 is held by a blade holder 30A in a cantilevered fashion and is driven by the motor 22 and the transmitting mechanism 23 as in the case of the head recovery device 26, so that the blade can be engaged by the discharge surface of the ink jet head cartridge 20. Thus, at a proper timing during the recording operation of the ink jet head cartridge 20 or after the discharge recovery treatment of the head recovery device 26, the blade 30 is extended into the moving path of the ink jet head cartridge 20, so that the ink droplets, ink liquid and/or dirts deposited on the discharge surface of the ink jet head cartridge 20 is removed by the blade in response to the movement of the ink jet head cartridge 20. As mentioned above, by carrying out the manufacturing method relating to the bonding according to the present invention, it is possible to obtain a plurality of heads collectively, and to bond the work stably at high production speed, without the positional discrepancy and the poor bonding.

Claims: An ink jet head manufacturing method including a pressurizing step, wherein a base member (1) and a top member (2) are pressed and bonded together via wall members (3, 4) defining liquid passages (5) which communicate with discharge openings for discharging ink, said pressure is applied to the base (1) and top member (2) substantially except for areas where said liquid passages (5) are formed, so that only the wall members (3) are pressurized. An ink jet head manufacturing method according to claim 1, wherein recessed portions (14) are formed in a pressure member (13) for performing the pressurization, in correspondence to said areas where said liquid passages (5) are formed. An ink jet head manufacturing method according to claim 1, wherein the pressurization is effected in a condition that a thin elastic film (12) is interposed between said pressure member (13) and a member to be pressurized. An ink jet head manufacturing method according to claim 3, wherein said thin elastic film (12) has a hardness of 40 - 85 degrees measured by an A-type hardness tester of K6301 spring type in the Japanese Industrial Standard, and a thickness of 0.2 to 1 mm. An ink jet head manufacturing method according to claim 1, wherein the bonding is effected in a condition that an ultraviolet ray curable adhesive layer is interposed between said top member (2) and said base member (1). An ink jet head manufacturing method according to claim 5, wherein said ultraviolet ray curable adhesive layer has a thickness of 1 - 5 µm. An ink jet head manufacturing method according to claim 5, wherein said pressure member (13) for performing the pressurization is permeable to ultraviolet rays. An ink jet head manufacturing method according to claim 5, further including a curing step for curing said ultraviolet ray curable adhesive by illuminating the ultraviolet rays thereon after said pressurizing step. An ink jet head manufacturing method according to claim 1, wherein said base member (1) and said top member (2) are both plate-shaped. An ink jet head manufacturing method according to claim 1, wherein the pressurization is effected while heating. An ink jet head manufacturing method according to claim 1, wherein the heating is effected before said pressurizing step. An ink jet head manufacturing method according to claim 1, further inlcuding a temporary adhesion step for temporarily adhering said top member (2) to said base member (1) at a plurality of points around said areas where said liquid passages (5) are formed. An ink jet head manufacturing method according to claim 12, wherein the temporary adhesion is effected by using a two liquid component elastic adhesive. An ink jet head manufacturing method according to claim 1, further including a cooling step for cooling said member to be pressurized, while keeping the aforesaid pressurization. An ink jet near manufacturing method according to claim 1, wherein said liquid passages (5) include a plurality of ink paths communicating with corresponding plurality of said discharge openings, and ink chambers communicating with the plural ink paths in common, and wherein recessed portions (14) are formed in an inner surface of said top member (2) in correspondence to said ink chambers. An ink jet head manufacturing method according to claim 1, wherein energy generators for generating energy used to discharge ink from said discharge openings are disposed in the respective liquid passages. An ink jet head manufacturing method according to claim 16, wherein said energy generators comprise electrothermal conversion elements for generating thermal energy as aforesaid energy. An ink jet head manufacturing method according to claim 1, wherein a plurality of said discharge openings are arranged along a whole width of a recording medium on which an image is formed by ink discharged from said discharge openings. An ink jet head manufacturing method according to claim 1, further including a separating step for dividing the ink jet head into individual elements. An ink jet head manufacturing method according to claim 1, wherein said wall members (3, 4) are made of photosensitive resin. An ink jet head manufacturing method according to claim 15, wherein said base member (1) and said top member (2) are pressurized and bonded together, except for areas where said ink chambers are formed. An ink jet head manufacturing method according to claim 15, wherein said bash member (1) and said top member (2) are pressurized and bonded together, except for areas where said plural ink paths and ink chambers are formed. An ink jet head manufacturing apparatus for carrying out the method according to claims 1 to 22, including a pressure member (13) to pressurize a base member (1) and a top member (2) together via wall members (3, 4) defining liquid passages (5) which communicate with discharge openings for discharging ink, wherein said pressure member (13) applies pressure substantially in areas where wall members (3) are formed and not in areas where said liquid passages (5) are formed. An ink jet head manufacturing apparatus according to claim 23, wherein recessed portions (14) are formed in said pressure member (13) in correspondence to said areas where said liquid passages (5) are formed. An ink jet head manufacturing apparatus according to claim 23, further including a temperature adjusting means for adjusting temperatures of said base member (1) and said top member (2) via said wall members (3, 4). An ink jet head manufacturing apparatus according to claim 23, wherein the bonding is effected in a condition that an ultraviolet ray curable adhesive layer (7) is interposed between said top member (2) and said base member (1), and said pressure member (13) is permeable to ultraviolet rays, and wherein further including a ultraviolet lighting means for illuminating the ultraviolet rays onto said ultraviolet ray curable adhesive layer (7).

Inventors: ITO HITOSHI, SHIBATA MAKOTO, ITO, HITOSHI, SHIBATA, MAKOTO, Ito, Hitoshi, c/o Canon Kabushiki Kaisha, Shibata, Makoto, c/o Canon Kabushiki Kaisha
Applicants: CANON KK, CANON KABUSHIKI KAISHA
Application year: 1992
Main classification: B41J2
IPC codes: B29C65, B41J2, B29C35