Patent Application
20090128602
The present invention relates to an ink jet recording head to which a protective tape can be pasted to protect the head surface during the shipment of the ink jet recording head or the like occasions. More specifically, the present invention relates to an ink jet recording head characterized in that a part or parts of its surface at which the outward end of each of the ink jetting nozzles opens have been changed in properties to adjust the ink jet recording head in the fastness of the adhesion between the surface at which the outward end of each of the ink jetting nozzles opens, and a protective tape pasted thereto. The present invention also relates to an ink jet cartridge having such an ink jet recording head, and a method for manufacturing such an ink jet recording head.
In recent years, digital cameras or the like have been substantially increased in resolution. As a result, the use of recording apparatuses capable of recording a high quality photographic image has been steadily increasing, in particular, ink jet recording apparatuses, which record images by jetting ink toward recording medium. There have been known various methods used for causing the ink jet recording head of an ink jet recording apparatus to jet ink droplets. Ink jet recording heads which use heat as the energy for jetting ink can be relatively easily increased in resolution, that is, the number of ink jetting nozzles. In other words, an ink jet recording head can be relatively easily improved in terms of resolution, image quality, and recording speed. In spite of the increase in the desire for high quality recording, the demand for a recording apparatus capable of recording conventional business documents and web pages has not subsided. Rather, demand has been increasing for recording apparatuses which are not only capable of recording an ordinary document at a substantially higher speed and a substantially higher level of quality than an ink jet recording apparatus in accordance with the prior art, but also, a photographic image at a substantially higher speed and at a substantially higher level of quality than an ink jet recording apparatus in accordance with the prior art.
As the means for dealing with the above described desire, various ink jet recording apparatuses have been offered in the market. One type of such ink jet recording apparatus is characterized in that when it records an ordinary document, it uses pigment black ink (Bk), that is, the ink which is high in density, and jets relatively large ink droplets, whereas when it records a web page, not only does it uses the pigment black ink (Bk), but also, cyan (C), magenta (M), and yellow (Y) inks. Further, when it records a photographic image, it uses only color inks.
Also in recent years, in order to enable an ink jet recording apparatus to record at a higher level of quality, an ink jet recording apparatus has been further reduced in the size of the ink droplet it jets. Thus, the size of an ink droplet jetted by a recent ink jet recording apparatus is as small as several pico litres; a nozzle which jets an ink droplet, the size of which is several pico litres, is roughly 10 μm in the diameter of its opening, and is as thin as 10 μm in the thickness of its wall. In order to improve an ink jet recording head, such as the above described one, in the accuracy with which the ink droplet it jets lands on recording medium, the surface of the ink jet recording head, at which the ink jetting nozzles open, is processed to make the surface repel ink (Japanese Laid-open Patent Applications 2002-355979 (Patent Document 3), 2003-266720 (Patent Document 4)). Further, for the purpose of protecting the minute opening of each nozzle of an ink jet recording head while the ink jet recording is shipped, a protective tape is pasted to the surface of the ink jet recording head, at which each nozzle opens (Japanese Laid-open Patent Applications 5-084925 (Patent Document 1), 11-348316 (Patent Document 2), and 2004-148746 (Patent Document 5)). This protective tape is to be peeled when an ink jet recording head is used for the first time.
A protective tape which is to be pasted to an ink jet recording head is made up primarily of a substrate layer and an adhesive layer. If the adhesive layer is excessively adherent, it is possible for an ink jet recording apparatus to be damaged around the openings of the nozzles when the protective tape is removed. Thus, a protective tape, the adhesive layer of which is relatively weak in adhesiveness, is sometimes used. However, if a protective tape is excessively weak in adhesiveness, it is possible that the protective tape will peel and fall off a recording head when the recording head is clamped to be conveyed or packaged while the recording head is manufactured with the use of an automatic machine. Thus, various structural arrangements which prevent the portion of a recording head, which has a protective tape, from being clamped, have been tried. However, a protective tape sometimes peeled because of the vibrations which were attributable to the conveyance of the recording head, and/or the changes in the ambient pressure attributable the acceleration or deceleration of the recording head conveyance speed. In other words, a protective tape, the adhesiveness of which is not strong enough to possibly damage an ink jet recording head across the above mentioned areas, sometimes failed to remain satisfactorily adhered to protect the ink jet recording head.
Further, the surface of an ink jet recording head, at which the ink jetting nozzles are open, is entirely coated with an ink repellent, as described above. The presence of this ink repellent on this surface lessened the adhesion between this surface and a protective tape, resulting in the peeling of the protective tape. Even if a protective tape (adhesive layer) does not completely peel away from this surface, ink will leak; for example, even if a part of a protective tape separates from this surface by a gap of only 1 μm, ink will seep out through this gap due to the capillary action of the ink. As ink leaks, it solidifies during the shipment of the ink jet recording head, or the like occasions, causing the ink jet recording head to fail when the ink jet recording head is put to use by a user.
There are various proposals which were made to solve the above described problems. One of them (Japanese Laid-open Patent Application 2006-212796) is to process the adhesive layer of a protective layer to make the adhesive layer nonuniform in adhesiveness, in such a manner that the adhesive layer is weaker in adhesiveness across the areas in the immediate adjacencies of the opening of each nozzle, and stronger across the rest. Thus, not only can this arrangement prevent a protective tape from peeling, but also, prevent an ink jet recording head from being damaged across the portion immediately next to the opening of each nozzle.
This arrangement, however, requires the protective tape, which is nonuniform in adhesiveness, to be highly precisely positioned relative to a recording head when it is pasted to the recording head, possibly making complicated the process for pasting the protective tape to an ink jet recording head. In addition, if this protective tape fails to be accurately positioned so that the various areas of the protective layer, which are different in adhesiveness, are correctly positioned relative to the surface of an ink jet recording head, which has the nozzle openings, it is possible that the above described problems will occur.
The time to irradiate specific areas of a protective tape to achieve a desired level of adhesiveness between the specific areas of the protective tape and a recording head may be after the protective tape is pasted to the recording head after the completion of the recording head. However, this arrangement complicates the manufacturing process, and also, requires a manufacturing apparatus of a substantial scale.
The present invention was made to solve the problems described above, without using special processes and manufacturing equipment to manufacture an ink jet recording head, and without modifying a protective tape in adhesiveness, and its primary object is to provide an ink jet recording head, which does not suffer from the above described problem.
Another object of the present invention is to provide a method for changing in properties the surface of a recording head which has nozzle openings, in order to provide an ink jet recording head, which is characterized in that even through a protective tape which is uniform in adhesiveness is pasted to the surface of the ink jet recording head having nozzle openings, the adhesion (amount of force necessary to peel protective tape) between the protective tape and the surface having nozzle openings is nonuniform across the interface between the protective tape and the surface of the recording head having nozzle opening.
Another object of the present invention is to provide an ink jet recording head, which was changed in surface properties, across specific areas of the surface having nozzle openings, in order to achieve such an amount of adhesion between a protective tape and the surface having nozzle openings that allows the protective tape to be easily pealed by a user when it needs to be peeled, and yet, is sufficient to prevent the protective tape from peeling off from the ink jet recording head, without being large enough to damage the nozzle opening portions of the ink jet recording head when the protective tape is peeled.
Another object of the present invention is to provide an ink jet recording cartridge which employs the ink jet recording head described above. Yet another object of the present invention is to provide an ink jet recording manufacturing method capable of manufacturing an ink jet recording head, such as those described above, without requiring additional steps for achieving the objects described above.
An ink jet recording head which can achieve the above described objects is an ink jet recording head to which a protective tape is pasted across its surface having multiple rows of nozzle openings before it is shipped out, and is characterized in that the peel resistance between the protective tape and the surface having the multiple rows of nozzle openings is greater across the lengthwise end portions of the surface having the multiple rows of nozzle openings, that is, the areas in the adjacencies of the ends of rows of nozzle openings, than across the rest of the surface.
An ink jet recording head which can achieve the above described objects is an ink jet recording head to which a protective tape is pasted across its surface having multiple rows of nozzle openings before it is shipped out, and is characterized in that the peel resistance between the protective tape and the surface having the multiple rows of nozzle openings is greater across the lengthwise end portions of the surface having the multiple rows of nozzle openings, that is, the areas in the adjacencies of the ends of rows of nozzle openings, than across the rest of the surface, and also, that the areas which are higher in the peel resistance than the rest are greater in the amount of the oxygen in the surface layer than the rest.
The method for manufacturing an ink jet recording head which can achieve the above described objects is a method for manufacturing an ink jet recording head made up of: a recording head chip having a surface with multiple rows of openings of ink jetting nozzles; and a frame to which the recording head chip is attached, and is characterized in that in the step in which the recording head chip is temporarily fixed to the frame by irradiating energy rays thereupon, the lengthwise end portions of the surface having the multiple rows of nozzle openings, that is, the areas in the adjacencies of the ends of rows of nozzle openings, are irradiated with the same energy rays as the abovementioned ones to make them greater in the amount of the oxygen in the surface layer than the rest.
According to the present invention, the surface of an ink jet recording head, which has nozzle openings, and across which a protective tape is pasted, is irradiated across a specific area with energy rays, such as X-rays in order to change the area in properties, that is, to increase the area in the oxygen density in the surface layer, relative to the rest of the surface. With this treatment, this area is increased in the fastness of adhesion (peel resistance) between the adhesive layer of the protective tape and the area. Therefore, even a protective tape having an adhesive layer which is relatively weak in adhesiveness can be used to protect an ink jet recording head, just as effectively as a protective tape which is adherent enough not to peel off during the manufacturing or shipment, without being adherent enough to damage the nozzle opening portions of the ink jet recording head when the protective tape is peeled, and yet, can be easily pealed by a user when it needs to be peeled. In other words, it is possible to achieve three objectives which are contradictory, that is, the objective of making the adhesion between a protective tape and the surface of an ink jet recording head, which has nozzle openings, sufficient to protect the recording head during shipment, objective of preventing the nozzle opening portions of an ink jet recording head from being damaged when the protective tape is peeled before the ink jet recording head is used, and objective of making it possible for a protective tape to be easily peeled.
Further, according to the present invention, the energy rays used for temporarily fixing a head chip to the frame of an ink jet recording head, in one of the steps in an ink jet recording head manufacturing process, can be used in the same step to irradiate, the surface of the ink jet recording head, which has nozzle openings, across a specific area, with the use of the same energy rays, simply by adjusting the energy rays in range. In other words, a special manufacturing step and/or a special manufacturing apparatus for changing the surface properties is not needed.
These and other objects, features, and advantages of the present invention will become more apparent upon consideration of the following description of the preferred embodiments of the present invention, taken in conjunction with the accompanying drawings.
a) is a perspective view of the Bk ink jet cartridge, showing the essential portions thereof, and
a) is a perspective view of the Bk cartridge having the protective tape, and
a) is a perspective view of the Bk cartridge 103, and shows the essential portions of the Bk cartridge 103. The Bk cartridge 103 is provided with an ink jet recording head 123 and an electric wiring board 120. The ink jet recording head 123 (which hereafter may be referred to as recording element or recording head chip) is in the form of a chip. It jets ink by heating the ink with heat generating resistors. The electric wiring board 120 is for transmitting driving signals or the like from the ink jet recording apparatus 101 to the recording element 123. The recording element of the Bk cartridge 103 is solidly attached to the ink container 127 with the use of an adhesive which is curable with UV light. The Bk cartridge 103 is also provided with a seal portion 124 which protects the electrical joint between the recording element 123 and electric wiring board 120. The ink container 127 is provided with: a pair of guides 121 which are used when the Bk cartridge is mounted on the carriage 103; cartridge position reference surfaces 125 and 126, which are located on one of the lateral sides of the cartridge, in terms of the cartridge insertion direction; and the cartridge position reference surfaces on the other lateral side.
b) is a perspective view of the Cl cartridge 104, and shows the essential portions of the Cl cartridge 104. The Cl cartridge 104 is provided with an ink jet recording head 133, an electric wiring board 130, a seal portion 134, and an ink container 137, which are similar to those of the Bk cartridge. The ink container 137 is provided with: a pair of guides 131; cartridge position reference surfaces 135 and 136, which are located on one of the lateral sides of the Cl cartridge, in terms of the cartridge insertion direction; and the cartridge position reference surfaces on the other lateral side, which also are similar to those of the Bk cartridge.
a) and 4(b) show the Bk cartridge 103 and Cl cartridge 104, respectively, which have the protective tape. Designated by referential numbers 129 and 139 in the drawings are tab portions of the protective tapes 128 and 138, respectively, which are to be held by a user when the user intends to peel the protective tapes. These portions 129 and 139 are not provided with the adhesive layer. Further, the protective tapes 128 and 138 are provided with dimpled portions 151 and 161, that is, the portions dimpled to reduce the protective tapes 128 and 138 in the size of the contact areas between the protective tapes 128 and 138, and the Bk and Cl cartridges 103 and 104, respectively, in order to prevent the protective tapes 128 and 138 from firmly sticking to the electrical wiring boards 120 and 130, ink containers 127 and 137, etc., respectively.
The Bk cartridge 103 and Cl cartridge 104 are roughly the same in structure. Hereafter, therefore, this embodiment will be described with reference to the Bk cartridge 103 alone.
If the ink jet recording apparatus 101 which uses an ink jet recording cartridge, such as the above described Bk cartridge, runs out of the ink in the ink container 127, the entirety of the recording cartridge (Bk cartridge) is replaced with a brand-new one. In other words, a combination of a recording head, and an ink container containing black ink, is sold as the Bk cartridge in the market. In order to sell the Bk cartridge in the market, the Bk cartridge must be distributed to various markets. Thus, the Bk cartridge must be protected from the shocks to which it is subjected during its shipment, and also, the ink in the ink container must be prevented from drying up. In particular, the recording element 123 is very delicate; it is easily damaged, and also, is easily affected in performance by the ink having adhered thereto as it dried up. Thus, the sensitive portions of the Bk cartridge 103 are covered (protected) by the protective tape 128 before the Bk cartridge 103 is distributed.
The protective tape 128 is made up of a substrate layer and an adhesive layer. The substrate layer is formed of polyethylene terephthalate or the like, and the adhesive layer is formed of an acrylic adhesive, or an adhesive of the so-called hot-melt type. The protective tape 128 protects the opening of each nozzle and its adjacencies by being adhered to the surface of the recording element 123 by its adhesive layer in a manner to cover the opening of each nozzle. When a brand-new Bk cartridge 103 is mounted as the replacement for the used Bk cartridge 103 into the ink jet recording apparatus 101, the protective tape 128 on the recording element 123 of the replacement Bk cartridge 103 is to be peeled away by a user.
In order to improve the recording element 133 in reliability, the entirety of the surface G of the recording element 133 has been processed to make the surface G repel ink; the surface G is treated with alkyl-siloxane epoxy resin which contains fluorine. Further, before the protective tape is pasted, the two long and narrow areas 11 (which are located in the outward adjacencies of the ends of the rows 142C, 143M, and 144Y of nozzle openings of the recording element 133, and extend in the width direction of the recording element 133) of the surface G, which constitute parts of the lengthwise end portions of the surface G, are irradiated with UV light, using EXECUR 3000 (product of Hoya Candeo Optronics, Co., Ltd.).
At this time, the changes, which occur to the surface of the material for the substrate of the recording element 133 as the material is irradiated with UV light, will be described. Ultraviolet rays with a short wavelength are high in photo-energy, being therefore capable of severing molecular bonds, enhancing chemical reactions, etc. Thus, as UV light is projected onto the surface of a given substance, the UV light strikes oxygen molecules, generating thereby ozone. This ozone absorbs the UV rays and/or heat, breaking into active oxygen, and the active oxygen oxidizes or removes the organic substances on the surface of the substance. The UV light, the wavelength of which is a certain range, is greater in energy than the covalent bond energy, being therefore capable of directly severing the covalent bonds within a molecule. Thus, in some cases, using UV rays, the wavelength of which is in a certain range, can offer a cleaning effect which cannot be achieved by the so-called wet cleansing. Moreover, acyl group (COH), hydroxyl group (OH), carboxyl group (COOH), etc., are generated, by active oxygen, on the surface of the substance being irradiated with the UV rays. Thus, as the abovementioned long and narrow portions of the surface G, that is, the surface of the recording element, which has the nozzle openings, is irradiated with the UV rays, they increase in the amount of the oxygen on them, being thereby improved in terms of the efficiency with which they chemically bond with the adhesive layer of the protective tape.
Shown in
At this point in time, the measurement of the peel resistance will be described in more detail. The peel resistance, in
The peel resistance is affected by the choice of the substance used as the material for the substrate layer of the protective tape, and the choice of the adhesive used to form the adhesive layer. Therefore, it is important to the present invention that the peel resistance of the protective tape relative to the surface of the recording element, which has the nozzle openings, is set according to the material for the substrate of the recording element.
The present invention resulted from the attention paid to the above described changes, in the amount of the peel resistance of the protective tape relative to the surface of the recording element, which occurred as the surface was changed in the properties by the UV light. Thus, according to the present invention, the adhesiveness (which may be referred to as peel resistance, or amount of force necessary to peel protective tape from recording head) between the surface of the recording element having the nozzle openings, and the protective tape, is increased by increasing the surface layer of the recording element 133, in the amount of the oxygen therein by irradiating the surface with UV light. The portion of the recording element 133, which has been changed in surface properties is likely to be greater in the adhesiveness relative to the protective tape 138, and lower in ink repellence (having greater affinity for ink), than the portion of the surface of the recording head 133, which has not been in properties.
In this embodiment, in consideration of the amount of peel resistance which the protective tape needs during its manufacturing process and/or shipment, the energy density of the UV light used for the surface property modification was set to 70 J/cm2. The amount of peel resistance of the protective tape, which can be estimated from
Incidentally, in consideration of the need for ensuring that the protective tape remains properly adhered to the aforementioned surface of the recording head, which has the nozzle openings, and also, that the protective tape can be peeled away without difficulty, the practical ratio of the amount of peel resistance of the protective tape relative to the portion of the surface of the recording head, which had been changed in properties, relative to the amount of the peel resistance of the protective tape relative to the portion of the surface of the recording head, which had not been changed in properties, is within a range of roughly 1.2-2.0 times. Further, in consideration of the need for ensuring that the recording head is easy to operate, and also, that the recording head is easy to manufacture, the ratio of the amount of peel resistance of the protective tape relative to the portion of the surface of the recording head, which had been changed in properties, relative to the amount of the peel resistance of the protective tape relative to the portion of the surface of the recording head, which had not been changed in properties, desired to be within a range of roughly 1.2-1.6 times.
In this embodiment, the surface of the recording element, which has the nozzle openings is irradiated with the UV light so that a space, the dimension of which in terms of the direction parallel to the rows of nozzle openings is L, is provided between each of the two irradiated areas 11, and the corresponding end of each row of nozzle openings, in order to ensure that even if ink collects on the areas 11 because the areas 11 reduce in ink repellence due to the exposure to the UV light, the ink does not interfere with the nozzle openings. The distance L is to be made as large as possible without causing structural problems to the recording element 133. In this embodiment, it was made to be 0.2 mm in width (L=0.2). Incidentally, the recording element 133 is provided with two rows 142C of nozzle opening, two rows 142M of nozzle openings, and two rows 142Y of nozzle openings, and each row of nozzle openings has 192 nozzle openings. Further, the recording element 133 is provided with a total of 16 dummy nozzle openings, that is, the nozzle openings which are not involved in the jetting of ink; one dummy nozzle opening is located at each end of each row of nozzle openings. The provision of these dummy nozzle openings further improves the recording element 133 in reliability in terms of the jetting of ink; even if ink collects on the abovementioned areas 11, it does not affect the recording element in ink jetting performance. The protective tape 138 is pasted to the surface of the recording element 133, which has the nozzle openings, so that the protective tape 138 covers at least one of the two areas 11, that is, the areas irradiated with the UV light, more specifically, the irradiated two areas of the lengthwise end portions of the surface of the recording element 133, which has the nozzle openings.
In this embodiment, acrylic adhesive was used as the material for the adhesive layer of the protective tape 138. However, the material for the adhesive layer may be silicone adhesive, or adhesive of the hot-melt type, as long as the material is adhesive enough to keep the protective tape 138 adhered to the recording element 133, without being adhesive enough to destroy the adjacencies of the nozzle openings of the recording element 133 when the protective tape 138 is peeled away from the recording element 133. Obviously, various substances can be used as the materials for the substrate layer of the protective tape 138 as long as they can achieve the objective of not destroying the nozzle opening portions of the recording element 133 when the protective tape 138 is peeled.
In this embodiment, the distance L between the lengthwise end of each row of nozzle openings and the corresponding area 11 was set to 0.2 mm. However, it does not need to be limited to 0.2 mm; it may be varied according to the specification of the recording element 133.
As described above, the adhesiveness of the protective tape 138 relative to the preselected area(s) of the recording element (which in this embodiment is lengthwise end(s) of surface of recording element, which has nozzle openings), can be changed (improved) by irradiating the preselected area(s) with the UV light, the energy density of which is in the preset range. In other words, the area(s) of the surface of the recording element, across which the protective tape 138 is to be pasted, can be changed in surface properties by the irradiation of the area(s) with the UV light, in order to make the adhesiveness between the abovementioned area(s) and protective tape 138 sufficient (that is, without being strong enough to damage the nozzle opening portions of the recording element when the protective tape is peeled) to prevent the protective tape from peeling away from the area(s) while the ink jet recording cartridge is manufactured or shipped, and yet, weak enough to allow the protective tape to be easily peeled away when the protective tape needs to be peeled away.
Designated by a referential number 13 is each of the areas of the recording element which are irradiated with UV light. The area 13 is smaller than the area 11, that is, the surface area of the recording element, which was irradiated with the UV light in the first embodiment. The areas 13 also belong to the surface of the recording element, which has the nozzle openings. Each of the areas 13 constitutes a part of the corresponding lengthwise end of the surface having the nozzle openings, as does each of the areas 11 in the first embodiment. This embodiment is different from the first embodiment in that the areas 13, which are equivalent to the areas 11 in the first embodiment, are substantially smaller in dimension in terms of the direction perpendicular to the rows of nozzle openings than the areas 11; they extend only in the adjacencies of the ends of the rows 143M of nozzle openings. The distance L from the lengthwise end of the row 143M of nozzle openings to the corresponding area 13 is the same as that in the first embodiment, which is 0.2 mm (L=2.0). The areas 13 were irradiated with the UV light, which was 70 J/cm2 in energy density, and the protective tape 138 was pasted to the surface of the recording element 133, which has the nozzle openings, in such a manner that at least one of the areas 13 is covered with the protective tape 138.
The protective tape 138 in this embodiment is provided with an adhesive layer which is more adhesive than the adhesive layer of the protective tape 138 in the first embodiment; the peel resistance of the protective tape 138, in this embodiment, pasted on the areas 13 (which had been changed in properties) of the recording element 133 was 100 N/m. Although the areas 13 in this embodiment were created by irradiating the surface of the recording element 133 with the UV light in a manner of spot lighting the specific surface areas of the recording element 133, it was satisfactory in terms of the peel resistance of the protective tape 138 relative to the areas 13 in that the protective tape 138 did not peel away from the areas 13, and also, that the problem that ink is allowed to leak by the local separation of the protective tape 138 from the areas 13 did not occur. In other words, the ink jet recording head in this embodiment was capable of withstanding the rigor of ordinary usage.
The ink jet recording cartridge, shown in
That is, the former is smaller than the latter, in the size of the area(s) which needs to be processed to be changed in properties, being therefore easier to process. Further, the former is processed only across the small center portion of the surface of the recording element, which has the nozzle openings, in terms of the direction perpendicular to the rows of nozzle openings. Therefore, the amount of force which must be used to peel the protective tape 138 away from the recording element 138 is relatively small at the beginning of the peeling. As the line of separation between the protective tape 138 and recording element reaches the areas 13, the peeling resistance temporarily increases and remains at that level while the protective tape 138 is peeled away from the areas 13. Then, as the line of separation moves past the areas 13, the peeling resistance reduces again. In other words, the protective tape 138 on the former easily peels at the beginning of the peeling operation, slightly increases in the resistance as it is further peeled, and then, comes off all at once. Thus, in the case of the ink jet recording cartridge in this embodiment, it does not occur that ink is unintentionally forced out of the nozzles by a user. Further, the areas 13, which had been changed in surface properties, are greater in the affinity for ink, being therefore easier for ink to adhere when the ink jet recording cartridge is mounted in the recording apparatus. However, the areas 13, that is, the portion of the surface of the recording element in this embodiment, which had been changed in properties, is smaller in size, and therefore, ink is less likely to collect on the areas 13 than it is on the areas 11, that is, the portion of the surface of the recording element in the first embodiment, which had been changed in properties.
Next, the method for changing the areas, shown in
In order to improve the areas 14 in terms of the peel resistance of the protective tape relative to the areas 14, the areas 14 are irradiated with the UV light at the same time as the abovementioned adhesive for solidly attaching the recording element 133 is irradiated with the UV light. During this step, the lateral surfaces of the retention mechanism 15 are also irradiated with the UV light. In other words, the retention mechanism 15 blocks the UV light, preventing thereby the nozzle opening portions of the recording element from being irradiated with the UV light.
As described above, in this embodiment, the ink jet recording cartridge is improved in terms of the adhesion of the protective tape to the areas 14 of the recording element, by irradiating the areas 14 with the UV light at the same time as the abovementioned adhesive for solidly attaching the recording element 133 is irradiated with the UV light. Thus, it is possible to improve the ink jet recording cartridge, in terms of the adhesion of the protective tape to the recording element 133, without need for a manufacturing step dedicated to the irradiation of the recording element 133 with the UV light.
Obviously, also in the first and second embodiments, the surface of the recording head, which has the nozzle openings, may be irradiated with the UV light in the step in which the recording element 133 is temporarily fastened to the ink container 137.
Designated by a referential number 21 is the surface area of the recording element 133, which is irradiated with the UV light in this embodiment. The areas 21 are located at the lengthwise ends of the recording element 123. There is provided a space, the dimension of which in terms of the direction parallel to the rows of nozzle openings is N, between the area 21 and the closest nozzle openings, that is, the nozzle opening located at the end of the row of nozzle openings. Therefore, even if ink collects on the area 21 (because area 21 is reduced in ink repellence by being irradiated with UV light), the ink does not interferes with the nozzle openings. In this embodiment, the distance N was set to be as large as possible without causing structural problems to the recording element 133. In this embodiment, it was set to 0.42 mm (N=0.42). The areas 21 were irradiated with the UV light, which was 70 J/cm2 in energy density, as was the UV light used in other embodiments, and the protective tape 128 was pasted to the surface of the recording element 123, which has the nozzle openings, in such a manner that at least one of the areas 21 is covered with the protective tape 128.
Incidentally, the difference in value between the distance N from the distance L (=0.2 mm) which is the distance between the area 11 and the corresponding end of each row of nozzle openings in the first embodiment, and the distance L in the second embodiment, comes from the difference in structure between the recording element for the CL cartridge and that for the Bk cartridge. That is, from the standpoint of structure, the Bk cartridge is more likely to allow ink to seep across the aforementioned space between the area, which was irradiated with the UV light, and the end of each row of nozzle openings, than the CL cartridge. Therefore, the distance N was made greater than the distance L (L<N).
As the specific areas of the lengthwise end portions of the surface of the recording element 123 to which the protective tape 128 was to be pasted were irradiated with the UV light as described above, the surface of these areas, which were ink-repellent, were improved in terms of the fastness of the adhesion of the protective tape 128 to these areas. As a result, as the protective tape 128 was pasted to the recording element 123, the fastness of the adhesion between the protective tape 128 and the recording element 123 became sufficient (that is, without being strong enough to damage the nozzle opening portions of the recording element when the protective tape is peeled) to prevent the protective tape from peeling away from the ink jet recording cartridge while the ink jet recording cartridge was manufactured or shipped, and yet, weak enough to allow the protective tape to be easily peeled away when the protective tape needed to be peeled away.
Incidentally, in the preferred embodiments described above, ultraviolet rays are used as the means for changing in properties the surface to which the protective tape is to be pasted, in order to improve the fastness of the adhesion of the protective tape to the surface. However, the means does not need to be limited to ultraviolet rays. That is, means other than ultraviolet rays may be used as long as the surface to which the protective tape is to be pasted, can be changed in properties. For example, the surface may be irradiated with plasma.
The recording element mentioned in the description of the preferred embodiments described above may be made up of a substrate formed of silicon or the like, an electrical circuit board, and a connective portion(s) which connects the substrate and electrical circuit board.
An ink jet recording cartridge to which the present invention is applicable is an integrated combination of an ink jet recording head and an ink container. As the ink in an ink jet recording cartridge of this type is completely consumed, the cartridge is to be replaced by a user. In recent years, from the standpoint of environmental concerns, it has come to be required to study the program for recycling used ink jet recording cartridges of this type.
An ink jet recording cartridge, which is in the form of an integrated combination of an ink jet recording head and an ink container, remains wet with ink for a while, across its surface having the nozzle openings, after it is used. This ink on the surface of the ink jet recording cartridge, which has the nozzle openings, dries up with the elapse of time. Thus, after a certain length of time (several weeks, for example), the surface will be covered with the solidified ink.
Recording heads which were in the above described condition were cleaned, and the amount of oxygen on the surface of each recording head, which had the nozzle openings, was measured.
Thus, when recycling ink jet recording cartridges, it is very important to thoroughly clean the surface of the recording element of each cartridge, which has the nozzle openings.
As described above, changing specific surface areas of the recording element of an ink jet recording head, which has the nozzle openings is advantageous in that it can provide a conventional protective tape (protective tape in accordance with the prior art) with a proper amount of peel resistance relative to the surface having the nozzle openings, without modifying the protective tape.
Incidentally, the apparatus used to measure the amount of peel resistance in this embodiment had an error of roughly 10%. Obviously, the peed resistance of a protective tape relative to a given surface is affected in numerical value by the level of the adhesiveness of the protective tape. Yet, the apparatus used to test the ink jet recording cartridges in the preferred embodiments described above can correctly show the relationship that a protective tape is greater in peel resistance when it is pasted to a surface area of an ink jet recording cartridge, which had been changed in properties than when it is pasted to a surface area of an ink jet recording cartridge, which had not been changed in properties.
The present invention provides an ink jet recording head having ejection outlets which is properly protected, without using special processes and manufacturing equipment to manufacture an ink jet recording head, and without modifying a protective tape in adhesiveness, and its primary object is to provide an ink jet recording head.
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.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2006-119648 | Apr 2006 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2007/059285 | 4/23/2007 | WO | 00 | 12/6/2007 |
