JP2834949B2 - Improved cleaning member for ink jet head and ink jet device provided with the cleaning member - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved cleaning member for removing an adhering substance attached to a discharge port surface of an ink jet head for performing recording by discharging ink, and an ink jet apparatus provided with the cleaning member.

The cleaning member comprises a polyurethane prepolymer, a bifunctional curing agent and a water repellency-imparting substance added thereto, and is superior to a conventional cleaning member particularly in cleaning durability.

[0003]

2. Description of the Related Art According to the ink jet system described in U.S. Pat. No. 4,723,129 and U.S. Pat. No. 4,740,796, high-speed, high-density, high-definition, high-quality recording is performed. Can be obtained.

[0004] Further, according to the ink jet system, color recording and the like can be easily achieved, and further, since the recording head can be manufactured using semiconductor technology, the apparatus can be downsized. it can.

[0005] In such an ink jet system, an ink jet head having a plurality of ink ejection ports having extremely fine diameters is used.

At the time of recording, ink is ejected from these ink ejection ports in response to a predetermined recording signal input,
Attached on the recording medium.

In a conventional ink jet head, continuous ink is continuously ejected, and the ejected ink is selectively attached to a recording medium, and only ink droplets necessary for recording are intermittently ejected. There is an on-demand format.

[0008] The on-demand type ink jet head is a full line type in which a plurality of ejection ports are arranged corresponding to the recording width of the recording medium, and the ink jet head is moved relatively to the recording medium. A serial scanning type of recording is known as a typical example.

[0009] In an ink jet apparatus using such an ink jet head, there are the following problems with the ink jet head. That is, in the case of an ink jet head that discharges particulate ink from a discharge port formed with a small diameter, dust, dust or paper powder from a recording medium, and ink droplets existing in the recording apparatus. May adhere to the discharge port surface or the vicinity of the discharge port as shown in FIGS. 7 (a) and 7 (b). Due to the effects of these deposits, the flight trajectory of the ink particles ejected from the ejection port may become unstable, or the deposit may dry and solidify to close the ink ejection port, making ejection impossible.

As one of means for solving this problem, polyether urethane rubber, polyester urethane rubber,
There is known a blade cleaning method in which a discharge port surface is rubbed with a blade made of an elastic member such as hydrogenated nitrile rubber or silicone rubber to wipe off attached matter.

By the way, in addition to an ink jet recording apparatus that performs recording in a single color, a demand for a full-color ink jet recording apparatus having four ink jet heads for ejecting four color inks such as yellow, magenta, cyan, and black is increasing. I have. In the printing in which the color tone is changed by using the four color inks, it is necessary to discharge a plurality of different inks for one dot, so that the ejection accuracy is required more than that of a conventional apparatus for performing single color printing. .

Therefore, it is necessary to always clean the state of the discharge port surface of the recording head that discharges each color and maintain a stable ink discharge state.

[0013] As a usage mode of the cleaning blade in such a full-color printing apparatus, there are a mode in which an independent cleaning blade is provided for each print head, and a mode in which each print head is cleaned by one common cleaning blade. In particular, from the viewpoint of reducing the area occupied in the recording apparatus and achieving compactness, a cleaning method of cleaning four recording heads with one cleaning blade is preferable.

In such a cleaning method, since the recording head which continuously discharges different inks is cleaned, the inks may be mixed on the blade, resulting in a color defect of an image. As one of the cleaning methods for solving this problem, by sequentially cleaning the recording heads that eject relatively light ink to the recording heads that eject dark ink, the influence of color mixing on the recording head that ejects light ink is reduced. Methods have been proposed to substantially eliminate them.

As another method, an ink absorber or the like is provided between each of the color inkjet heads, and one head is cleaned with a cleaning blade.
There has been proposed a configuration in which ink adhering to the cleaning blade is wiped by the ink absorber, so that when the next head is cleaned, the influence of the ink of the head that has been cleaned earlier is not affected.

Hereinafter, a proposed method described later will be briefly described with reference to FIG. A main scanning carriage 2 having an inkjet head 1 moves on a main scanning rail 3. Further, a cleaning blade 4 is disposed at a position where the cleaning blade 4 is in contact with the discharge port surface 1a of the ink jet head 1 in a non-recording area outside the recording area of the recording apparatus. 5 is a cleaning blade 4
Is a holder for fixing. When the main scanning carriage 2 moves and scans in the direction of arrow A, the cleaning blade 4 provided in the non-recording area rubs the discharge port surface 1a,
Adhered matter X such as ink droplets, paper dust, dust, etc. attached to the discharge port surface 1a is removed from the discharge port surface 1a using the edge of the cleaning blade 4. Then, the ink adhering to the cleaning blade 4 is removed by the ink absorber 6 provided between the respective inkjet heads, and the cleaning blade 4 cleans the next inkjet head in a cleaned state. Therefore, all the recording heads ejecting different inks can be satisfactorily cleaned by the cleaned cleaning blade without causing color mixture between the recording heads.

In this case, in one cleaning operation, the cleaning blade and the head are rubbed by the number of the arranged ink jet heads, and the number of times of head rubbing of the blade is increased as compared with the conventional case.

On the other hand, in the field of ink jet recording, in recent years, from the viewpoint described below, research and development on high-speed recording and research and development for enabling a very large amount of recording with a single model using a recording head as an exchange type have been carried out. It has been done.

For example, in a high-speed recording apparatus, the amount of ink ejected per unit time increases, so that ink tends to adhere to the ejection opening surface of the recording head. There is a necessity of shortening the cleaning timing and performing many cleanings.

Further, in an apparatus capable of recording a large amount of data, the recording head is replaced a plurality of times and used for a long period of time, so that the number of times of cleaning the recording head by the blade becomes extremely large.

As described above, in various ink jet recording apparatuses, the cleaning operation by the cleaning blade is repeated very many times. Further, when performing the above-described color recording, as described with reference to FIG. 1, not only the ejection opening surface of the recording head but also the ink absorber provided between the heads, so that the number of rubbing of the blade is Increase further.

Therefore, it is desired that the cleaning blade be improved in durability as a characteristic thereof.

Conventionally, silicone rubber, hydrogenated nitrile rubber, polyester urethane rubber, polyether urethane rubber, and the like have been used as the elastic member for the cleaning blade used in the blade cleaning method. have.

Silicone rubber has low abrasion resistance, and when the silicone rubber is worn by continuous rubbing with the ink jet head and the ink absorber, cleaning performed using the edge portion of the blade cannot be sufficiently performed. There is. In other words, the worn cleaning blade cannot pass through the ink from the contact portion with the head ejection port surface, or cannot sufficiently remove the attached matter. As a result, the flight trajectory of the ink particles ejected due to the residual ink or the residual substance due to the defective cleaning becomes unstable, causing an image defect (streak due to distortion or non-discharge) or abrasion powder of the cleaning member to the nozzles of the inkjet head. Clogging may hinder ink ejection, resulting in an image defect (streak due to non-ejection). In addition, an inorganic filler such as silica in the silicone rubber may damage the vicinity of the ejection port of the ink jet head, causing the flight trajectory of the ink particles to become unstable, resulting in an image defect. Furthermore, image defects due to oil components in the silicone rubber deteriorating the ink (imprinting due to defective foaming causes streaks)
May occur. Furthermore, when a silicone rubber blade is used in an ink jet method in which droplets are ejected from an ejection element using thermal energy to perform recording, an oil component in the silicone rubber enters the ink ejection port,
The heating element for applying thermal energy may be burned by the oil component, making it impossible to eject ink and causing an image defect.

Further, the hydrogenated nitrile rubber has low abrasion resistance similarly to the silicone rubber, and particularly when applied to a color ink jet recording apparatus provided with the above-described ink absorber, the hydrogenated nitrile rubber is not compatible with the ink jet head and the ink absorber. Due to the rubbing, the blade will be significantly worn in long-term use, and ink cleaning will not be performed sufficiently.
Ink and adhering matter are left near the nozzles, thereby deteriorating ejection accuracy and causing image defects such as color misregistration. Further, hydrogenated nitrile rubber contains an oil component to lower its rubber hardness. However, similar to the case where the oil component is silicone rubber, the oil component penetrates into the head and burns the heating element or ink. May be changed.

Further, in the case of urethane rubbers such as polyester urethane rubber and polyether urethane rubber, there is no need to add an inorganic filler and an oil component. Since it is relatively excellent in abrasion resistance, it is currently widely used as a cleaning blade material for an ink jet head.

However, although urethane rubber is excellent in abrasion, when it is applied to a color ink jet recording apparatus as shown in FIG. 1, cleaning is performed by continuously rubbing with four ink jet heads and an ink absorber. In the case where the number of times is extremely increased, FIG.
As shown in (1), chipping of the material occurs at the edge of the blade, resulting in uneven wear (roughened state). Such uneven wear makes it impossible to sufficiently clean the ink during the cleaning operation, and the portion where chipping occurs is caused by the unevenness shown in FIG.
As shown in (b), an ink loss 10B occurs and ink remains near the nozzle. As a result, there is a possibility that the remaining ink in the vicinity of the nozzle may disturb the flight trajectory of the ejected ink at the time of ejecting the ink, causing a so-called misalignment defect. Further, when uneven wear increases and the amount of remaining ink increases, the discharged ink is drawn into the remaining ink, and printing may not be performed. In addition, when uneven wear occurs at the blade edge, the pressure of the blade is concentrated on the non-dropped edge and the contact area with ink (meniscus) increases, facilitating ink withdrawal from the nozzle. May occur (FIG. 5B).

In addition, polyester urethane rubber is easily hydrolyzed due to its structure. In the case of an ink jet recording apparatus using water-based ink, the rubber deteriorates due to water in the air or water in the ink, and loses elasticity. As a result, normal contact pressure was not applied to the edge, and the edge could not withstand long-term use.

Further, since urethane rubber has a polar group in its structure, it is generally easy to absorb water-based ink used in an ink jet recording apparatus. Therefore, when it is in contact with the ink for a long time, the urethane rubber swells with the ink. I will. As a result, at the time of cleaning, the cleaning blade pulls out the ink inside the nozzle with its affinity (FIG. 5B), and the ink remains in the vicinity of the nozzle, and the remaining ink affects the ejection direction of the ink. In some cases, this may cause a defect or make it difficult to remove the ink remaining on the blade surface after cleaning, and may leave the blade as dirt, which may cause a reduction in cleaning performance at the next cleaning. In particular, when applied to an ink jet recording apparatus using multi-color inks, color misregistration due to poor ejection accuracy becomes a problem as described above, and further, at the stage of removing residual ink wiped from the head with a cleaning blade with an ink absorber. If the affinity between the cleaning blade and the ink is strong, the ink cannot be sufficiently removed, which may cause color mixing.

The problem with the various blade materials as described above does not cause much problem in the current personal type recording apparatus in which the number of printed sheets at one time is relatively small and the frequency of use thereof is not so large. In other words, a personal type apparatus generally performs monochromatic recording, and the use state of the apparatus is that the number of recordings per recording is small and cleaning is frequently performed as described above. Because there are many.

However, for a full-color recording apparatus, a high-speed recording apparatus, and a recording head exchange type apparatus which can be used for a long time as described above, it is used to recover and improve the print quality as compared with a personal machine. The frequency of use of the cleaning blade is extremely high, and high reliability or durability is required. In particular, in a full-color recording apparatus, as described above, the cleaning blade is continuously rubbed with, for example, a plurality of recording heads and a plurality of absorbers in a single cleaning operation, so that the number of times of rubbing with the head or the like becomes substantially large. Also, high reliability is required.

[0032]

Under such circumstances, the present invention is particularly suitable as a cleaning blade for a recording apparatus of the type in which a high-quality image is required or used for a long time. It is intended to provide a unique material.

The present inventors have conducted various studies to improve the above-mentioned problems, and as a result, among those listed as various blade materials, inorganic fillers, oil components, etc., which are particularly likely to affect inks and recording heads. We have focused on polyurethane rubber-based materials that do not require the addition of and are relatively excellent in abrasion resistance. Using this material, various experiments such as selection of constituent materials, change and adjustment of additives, and the like were performed, and the following views were obtained.

First, an opinion on the improvement of the abrasion of the cleaning blade will be described.

In general, as a curing agent for a polyurethane rubber, a bifunctional component as a chain extender and a trifunctional or higher polyfunctional component as a crosslinking agent are used.

The polyfunctional component plays a role in making it difficult for slippage or displacement between neighboring molecules to occur when rubber is deformed because the neighboring molecules are connected by a chemical bond. As a result, it is possible to produce a rubber which is hardly permanently deformed and has a small compression set. However, since the polyfunctional component restricts the movement of nearby molecules, the interaction between polar groups in the urethane rubber (aggregation) and the interaction between main chain molecules (crystallization) are hindered. As a result, the strength (tear strength, tensile strength) of the rubber decreases. In particular, in the case of a polyether-based urethane, the difference in tensile strength and tear strength depending on the presence or absence of the polyfunctional component appears remarkably.

According to the investigations of the present inventors, it has been found that the form of wear differs depending on the presence or absence of the polyfunctional component. That is, when a polyether urethane rubber prepared by compounding a rubber having a multifunctional component was examined for wear using an ink jet recording apparatus as shown in FIG. 9 described later, the discharge port surface of the recording head of the cleaning blade was examined. 4 (b), a partial chipping of the material occurs as shown in FIG. 4 (b), resulting in an uneven wear mode. On the other hand, as shown in FIG. 4 (a), it was found that the rubbing surface of the blade had a uniform wear form without any chipping, as shown in FIG. 4 (a).

This difference in the form of wear causes a serious problem in the cleaning blade for an ink jet recording apparatus. That is, when uneven wear due to chipping occurs as shown in FIG. 4B, ink slippage 10B occurs from the chipped part during the cleaning operation as shown in FIG. Leave the ink in the vicinity,
This may cause printing defects such as deflection and non-ejection. When chipping further occurs, the pressing pressure of the blade against the head,
It concentrates on the edge portion where no chip is generated, and as a result, ink is drawn out from the nozzle. on the other hand,
Polyurethane rubber composed of bifunctional components causes uniform abrasion, so there is no chipping of the blade edge, ink does not slip through, and even pressure is applied, minimizing ink withdrawal from nozzles. And good cleaning is performed as shown in FIG.

Here, the drawing of ink will be described with reference to FIGS.

The cleaning blade 4 for rubbing the ink discharge port surface 1a of the recording head is pressed with an appropriate pressure. For this reason, in the cleaning blade 4 in which chipping has occurred as described above, stress concentrates on an edge portion where no chipping has occurred, and as shown in FIG. 2, the edge portion of the cleaning blade 4 is located inside the ink discharge port 1b. May invade. Meanwhile, a meniscus M is formed at the ink discharge port 1b by a predetermined surface tension of the ink existing in the ink liquid path and a negative pressure applied to the ink.

When the edge portion where the stress of the blade 4 is concentrated enters the ink discharge port 1b, the edge portion may contact the meniscus M portion of the ink depending on the amount of the penetration. When the blade moves in the state of contact with the ink, the ink that has contacted the blade is drawn out of the ejection port 1b (FIG. 5B).
Here, the ink pool existing between the cleaning blade 4 and the ink discharge port surface 1a of the recording head indicates the ink scraped by the cleaning operation.

On the other hand, a polyether polyurethane-based cleaning blade formed using only a bifunctional component as a curing agent does not cause chipping or the like and does not concentrate stress. The phenomenon of intruding into the outlet 1b is unlikely to occur.

Even if the edge of the blade penetrates into the discharge port, the amount of penetration is extremely small, so that contact with the meniscus M hardly occurs. Furthermore, a polyurethane-based cleaning blade using only a bifunctional curing agent shows uniform wear. Therefore, even if the cleaning blade is worn as shown by the broken line in FIG. 3, the edge portion of the blade hardly penetrates into the discharge port 1b. Further, even if the edge of the abraded cleaning blade enters the discharge port, the amount of penetration is very small, and hardly makes contact with the meniscus M of the ink. In other words, even if the cleaning is performed, it is extremely unlikely that the ink is drawn out from the ejection port.

On the other hand, the following opinion was obtained regarding the improvement of the water repellency of the cleaning blade.

As shown in FIG. 2, during the cleaning operation, the blade 4 enters the discharge port 1b, comes into contact with the meniscus M of the ink formed in the discharge port with the movement of the blade, and the ink adhered to the blade. The phenomenon of drawing out the ink (the amount of ink drawn out by the surface tension of the ink itself and the water repellency of the blade) varies depending on the water repellency of the blade material. Here, FIG. 6 shows the relationship between the contact angle and the adhesion area. As is clear from FIG. 6, the smaller the contact angle θ of the blade material, the larger the ink adhesion area to the blade, and the larger the contact angle θ, the smaller the ink adhesion area. That is, when the blade 4 finishes passing through the ejection port, the ink contact angle at the portion where the blade and the ejection port 1b are in contact is related to the amount of ink drawn out. The lower the water repellency of the blade, the smaller the contact angle becomes. This tends to increase the amount of ink drawn out due to an increase in the amount of ink adhering to the ink. Therefore, under the condition that the ink easily adheres to the blade material, the ink that has once adhered to the blade at the discharge port portion does not separate from the blade, and the ink is easily pulled out from the discharge port along with the movement of the blade by cleaning. (FIG. 5 (b)).

That is, by imparting water repellency to the cleaning blade, the contact angle between the ink and the cleaning blade is increased, the adhesion of ink can be reduced, the amount of ink withdrawn by cleaning is reduced, and a good cleaning state is obtained. Can be achieved.

[0047]

SUMMARY OF THE INVENTION The present invention has been made based on the results of the studies made by the present inventors as described above.
A blade is formed from a material using a functional curing agent and further to which a water repellency-imparting substance has been added, and by using this, recording is performed for a long period of time. An object of the present invention is to provide a cleaning blade for an ink jet head which does not have uniform wear, can always maintain good cleaning even during long-term use, and prevents ink from being drawn out from nozzle portions of the ink jet head.

In addition, by imparting water repellency to the elastic member having excellent abrasion resistance, ink breakage from the cleaning blade is improved, ink is not drawn out from the discharge port, and an ink jet head capable of giving a good image is provided. The present invention provides a cleaning blade. Furthermore,
It is another object to provide an ink jet recording apparatus using these cleaning blades.

According to the present invention, there is provided a cleaning member for removing deposits attached to an ink discharge surface of an ink jet recording head which discharges ink to perform recording on a recording medium. A cleaning member for an ink jet head, wherein the curing agent component of the ether-based polyurethane rubber elastic body is composed of only bifunctional components.

Further, the present invention relates to a cleaning member for removing deposits attached to an ink discharge surface of an ink jet recording head which discharges ink to perform recording on a recording medium, wherein the cleaning member is made of a polyurethane rubber elastic body. And a curing agent component of the polyurethane rubber elastic body is composed only of a bifunctional component, and further contains a water repellency-imparting substance having an active group capable of chemically bonding to the polyurethane rubber. It is a cleaning member.

Further, the present invention relates to an ink jet apparatus provided with a support member on which an ink jet head for discharging a water-based ink to perform recording on a recording medium can be mounted, and the recording medium is conveyed through the support member. Means for scanning between a recording area and a non-recording area outside of the area, and a cleaning blade capable of cleaning a discharge port surface of the head in the non-recording area; Is an ink jet apparatus characterized by comprising an ether-based polyurethane rubber elastic body, and wherein the curing agent component of the ether-based polyurethane rubber elastic body is composed of only bifunctional components.

Further, the present invention relates to an ink jet apparatus provided with a support member on which an ink jet head for discharging an aqueous ink to perform recording on a recording medium can be mounted,
Means for scanning the support member between a recording area where the recording medium is conveyed and a non-recording area outside the recording area, and the non-recording area is capable of cleaning the ejection surface of the head. A cleaning blade, wherein the cleaning blade member is made of a polyurethane rubber elastic body, and a curing agent component of the polyurethane rubber elastic body is composed only of a bifunctional component; and an active group capable of chemically bonding to the polyurethane rubber. An ink jet device comprising a water repellency-imparting substance having the following formula:

As the urethane raw material suitably used as the material of the cleaning blade of the present invention, an ethylene adipate type, a lactone type polyester type, a polycarbonate type, a polyether type or the like can be arbitrarily used. In particular, in consideration of hydrolyzability, polyether-based urethane is preferable. The polyether-based urethane material is obtained by reacting a polyoxytetramethylene glycol (hereinafter abbreviated as PTMEG) represented by the following general formula HO (CH ₂ CH ₂ CH ₂ CH ₂ O) _n H with a polyisocyanate. Commercially available polyether urethane raw materials include Vibracene B625, B635, and B67.
0, B821, B836 (trade name, manufactured by Uniroyal), Adiprene M400, M415, M467, M4
83, LW520, LW570 (trade name, manufactured by DuPont) and the like. Other polyether urethane raw materials include polyoxypropylene glycol (hereinafter referred to as PP) represented by the general formula HO (CH ₂ CH ₂ CH ₂ O) _n H.
G) and a polyether urethane raw material obtained by the reaction of a polyisocyanate, and commercially available products include Vibracene B843 (trade name, manufactured by Uniroyal), but are not limited thereto. .

The isocyanate to be reacted with the polyol is not particularly limited, and isocyanates conventionally used for producing polyurethane can be used. Examples thereof include diphenylmethane diisocyanate, tolylene diisocyanate, hexamethylene diisocyanate, and the like. Examples include naphthalene diisocyanate and hydrogenated diphenylmethane diisocyanate.

As described above, a bifunctional curing agent is required as a curing agent for the polyurethane raw material necessary for the blade to exhibit uniform wear properties. 2
Examples of the functional curing agent include 4,4-butanediol, 1,6-hexanediol, ethylene glycol,
Curing agents such as propylene glycol, polyethylene glycol, hydroquinone ethylol ether, bisphenol A, methylenebisorthodichloroaniline, and triethylene glycol para-aminobenzoate, and commercially available curing agents such as Vibracure-A120 and A9
31 (trade name, manufactured by Uniroyal), MOCA, and the like, and mixtures thereof can be used. Among them, straight-chain diols are preferred because they have good hydrolysis resistance and do not inhibit crystallinity. It should be noted that using only a bifunctional curing agent in the present invention does not prevent inclusion of a polyfunctional curing agent to the extent of impurities.

As the curing agent for the polyurethane raw material, not only the above-described bifunctional curing agent but also a polyfunctional curing agent can be used on condition that a water-repellent imparting member shown below is added. For example, as a multifunctional curing agent, trimethylolpropane, trimethylolethane,
Examples of general urethane curing agents such as glycerin and commercially available curing agents include Vibracure A125 and A51.
0, A567, Vibracene 3080, 3095 (trade name, manufactured by Uniroyal), and mixtures thereof.

In addition, the water repellency-imparting substance for improving the drawability of the blade used in the present invention with respect to ink is to prevent the water-repellency-imparting substance from bleeding and reducing the water repellency with time in long-term use. Preferably, a water repellency-imparting substance having one or more active groups in one molecule such as a hydroxyl group, an amino group, an epoxy group, and an isocyanate group which can chemically bond with the polyurethane material is preferable. In such a case, it is necessary to maintain the water repellency, so that a chemical structure having a low surface energy is present in the molecule.

Specific examples of water repellency-imparting substances include modified silicone compounds and reactive fluorine compounds. Examples of commercially available products include reactive fluorine compounds such as M
F100, MF110, MF120, M130 (manufactured by Mitsubishi Materials), Cm alcohol, HFIP (manufactured by Central Glass), PFA6 (manufactured by Neos), etc.
As modified silicone compounds, SF8417, BY1
Amino-modified silicone such as 6-828 (Toray Dow Corning), SF8411 (Toray Dow Corning)
Epoxy-modified silicone such as BX16-005, SF
8427, SF8428 (manufactured by Dow Corning Toray),
X-22-160AS (Shin-Etsu Silicone Co., Ltd.), DKQ
Examples thereof include, but are not limited to, alcohol-modified silicone such as 8-779 (manufactured by Dow Corning). Further, when a water-repellent substance having poor solubility in the polyurethane rubber material is used, the substance is present in the polyurethane rubber in the form of particles. If the water repellency-imparting substance is present in the form of particles, the effect of imparting water repellency to the polyurethane rubber is reduced, so that it is necessary to add more water repellency-imparting substance than necessary, and the physical properties of the rubber are somewhat deteriorated. In addition, the particle component may cause uneven wear of the urethane cleaning blade, and is not suitable for long-term use. Therefore, the water repellency-imparting substance is preferably present in a state of being compatible with the polyurethane rubber material. Further, in the case of an ink jet recording system in which a recording head discharges liquid droplets from a discharge element using thermal energy to perform recording, a modified silicone compound is not preferred in view of sticking of foreign matter to a heating element. Therefore, a reactive fluorine compound is particularly preferable in consideration of the solubility in the polyurethane rubber material and the risk of seizure of foreign matter on the heating element.

In the present invention, the ink contact angle (receding contact angle) of the blade is preferably 80 degrees or more.
In addition, those satisfying the amounts of the respective components described below have an ink contact angle included in the above-mentioned range.

In a preferred embodiment of the present invention, a blade material formed by using only a bifunctional curing agent as a curing agent for polyurethane of a cleaning blade and adding a water repellency-imparting substance thereto is used. No.

The cleaning blade having such a structure causes uniform wear peculiar to the blade formed of the bifunctional curing agent, and has a preferable contact angle with the ink obtained by adding the water repellency-imparting substance. Maintained, it is possible to reduce the draw-out of ink during cleaning, and it is possible to achieve good cleaning without ink slip-through at uniform pressure for a long time.

In the above embodiment, the sum of the number of moles of the bifunctional curing agent and the number of moles of the active element of the water repellency-imparting substance is set to 0.80 to 1.05 with respect to the number of moles of the isocyanate group contained in the polyurethane of the blade material. And more preferably 0.90 to 1.00.

The water-repellent substance is used in an amount of 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the total amount of the polyurethane and the curing agent.
If the amount of the water repellency-imparting substance is less than 0.1 part by weight, sufficient water repellency cannot be obtained, causing ink to be drawn out and causing color mixing. It is not preferable because it may cause a problem.

Of course, as a preferred embodiment of the present invention, a blade material constituted by using only a bifunctional curing agent for polyurethane, or a bifunctional curing agent, a polyfunctional curing agent, A blade material made of a substance is also included.

The use of only a bifunctional curing agent here does not prevent the inclusion of a polyfunctional curing agent to the extent of impurities.

The amount of the bifunctional curing agent added to the two types of blade materials listed as the preferred embodiments,
The addition amount of the water repellency-imparting substance satisfies the numerical values described in the description of the blade material of the example described as the optimal embodiment.

In order to manufacture the cleaning blade of the present invention, a predetermined amount of the polyurethane and the curing agent which have been heated and melted in advance, and further, the water repellency-imparting substance which has been heated as required are weighed, mixed and stirred, and defoamed as necessary. , A mold or a centrifugal molding machine, and heat-curing at 80 to 140 ° C. The water repellency-imparting substance may be mixed and reacted with the polyurethane raw material in advance, and then a curing agent may be added. Alternatively, the substance may be dissolved and dispersed in the curing agent in advance and reacted with the polyurethane.

According to such a method, since the water repellency-imparting substance is contained inside the polyurethane rubber, the water repellency does not decrease even when the surface is worn by rubbing.

The hardness of the molded rubber for the cleaning blade is preferably 40 to 90 degrees in JISA hardness in view of the cleaning property of the liquid ink.

The angle is more preferably 50 to 90 degrees.

[0071]

EXAMPLES Experiments Hereinafter, experiments performed by the present inventors will be described.

Experiment A Heat-dissolved polyethylene glycol (bifunctional curing agent,
22.7 parts by weight of molecular weight 1000) and 5.7 parts by weight of 1,4-butanediol (a bifunctional curing agent) were mixed, and Nn-propyl-N-2,3-dihydroxypropyl 3.6 parts by weight of fluorooctylsulfonamide (fluorine-based water repellency-imparting substance, trade name: MF110, manufactured by Mitsubishi Materials Corporation) was added and dissolved by heating with stirring at 90 ° C. to form a uniform solution.

This solution was heated at 80 ° C. with a polyurethane polymer (ether-based urethane PTMEG-MDI,
NCO content 7.7 wt%, trade name Vibracene B63
5, manufactured by Uniroyal Co.) 100 parts by weight of the active element of each of the curing agent and the water repellency-imparting substance with respect to the number of moles of the isocyanate group (hereinafter referred to as OH / NCO).
Was measured to be 1.00, stirred and mixed, and then defoamed under vacuum to obtain a uniform mixed solution.

This mixed solution was cast into a centrifugal molding machine previously heated to 130 ° C., and heat-cured for 1 hour. Thereafter, the mold was removed, and secondary curing was performed at 130 ° C. for 4 hours, and the thickness was 0.7 mm.
Then, a transparent sheet material containing a water repellency-imparting substance in an amount of 3 parts by weight based on the total amount of the polyurethane raw material and the curing agent of 100 was molded.

After cutting the sheet material, 10 mm × 1
Punched into a size of 5 mm, and a test blade A for each evaluation item described later was manufactured.

Experiment B: 23.6 parts by weight of polyethylene glycol, 5.9 parts by weight of 1,4-butanediol, Nn-propyl-N-
A transparent sheet material in which the content of the water repellency-imparting substance was adjusted to about 1 part by weight was formed in the same manner as in Experiment A except that 1.3 parts by weight of 2,3-dihydroxypropyl perfluorooctylsulfonamide was used. This was punched out under the same conditions as in Experiment A to produce a test blade B.

Experiment C: 21.6 parts by weight of polyethylene glycol, 5.4 parts by weight of 1,4-butanediol, Nn-propyl-N-
A transparent sheet material in which the content of the water repellency-imparting substance was adjusted to about 5 parts by weight was formed in the same manner as in Experiment A except that 6.3 parts by weight of 2,3-dihydroxypropyl perfluorooctylsulfonamide was used. This was punched out under the same conditions as in Experiment A to produce a test blade C.

Experiment D 24.0 parts by weight of polyethylene glycol, 6.0 parts by weight of 1,4-butanediol, Nn-propyl-N-2,
A transparent sheet material was prepared by adjusting the content of the water repellency-imparting substance to about 0.2 part by weight in the same manner as in Experiment A, except that 0.2 parts by weight of 3-dihydroxypropyl perfluorooctylsulfonamide was used. This was punched out under the same conditions as in Experiment A to produce a test blade D.

Experiment E 18.6 parts by weight of polyethylene glycol, 4.7 parts by weight of 1,4-butanediol, Nn-propyl-N-2,
A transparent sheet material was prepared by adjusting the content of the water repellency-imparting substance to about 10 parts by weight in the same manner as in Experiment A, except that the amount of the water-repellent-imparting substance was adjusted to 13.4 parts by weight with 3-dihydroxypropyl perfluorooctylsulfonamide. Was punched out under the same conditions as in Experiment A to produce a test blade E.

Experiment F: 14.1 parts by weight of polyethylene glycol, 3.5 parts by weight of 1,4-butanediol, Nn-propyl-N-2,
A transparent sheet material in which the content of the water repellency-imparting substance was adjusted to about 20 parts by weight was formed in the same manner as in Experiment A except that the amount of the transparent sheet material was 33.5 parts by weight of 3-dihydroxypropyl perfluorooctylsulfonamide, Was punched out under the same conditions as in Experiment A to produce a test blade F.

Experiment G 19.3 parts by weight of polyethylene glycol, 4.8 parts by weight of 1,4-butanediol, Nn-propyl-N-2,
A test blade G was manufactured in the same manner as in Experiment A, except that 3.2 parts by weight of 3-dihydroxypropyl perfluorooctylsulfonamide was weighed so that OH / NCO became 0.8.

Experiment H 23.8 parts by weight of polyethylene glycol, 6.0 parts by weight of 1,4-butanediol, Nn-propyl-N-2,
A test blade H was manufactured in the same manner as in Experiment A, except that 3.8 parts by weight of 3-dihydroxypropyl perfluorooctylsulfonamide was weighed so that OH / NCO became 1.05.

Experiment I In Experiment A, the water repellency-imparting substance was 3- (2-perfluorohexyl) ethoxy-1,2-dihydroxypropane (fluorine water repellency-imparting substance, trade name MF100, manufactured by Mitsubishi Materials Corporation). A test blade I was manufactured in the same manner as in Experiment A except that the amount was changed to 6 parts by weight.

Experiment J In Experiment A, the water repellency-imparting substance was C ₉ F ₁₇ O- (CH
₂ ) _6- OH (fluorine water repellency-imparting substance, trade name PFA
6, manufactured by Neos Co.) A test blade J was manufactured in the same manner as in Experiment A except that the weight was changed to 3.6 parts by weight.

Experiment K The test was conducted in the same manner as in Experiment A except that the water repellency-imparting substance was changed to 3.8 parts by weight of alcohol-modified silicone oil (silicone-based water repellency-imparting substance, manufactured by Toray Dow) in Experiment A. Blade K was manufactured.

Experiment L A test blade L was manufactured in the same manner as in Experiment A, except that polyethylene glycol was used in an amount of 24.3 parts by weight and 1,4-butanediol was used in an amount of 6.1 parts by weight. .

Experiment M Using only 69.8 parts by weight of polyethylene glycol as the bifunctional curing agent, Nn-propyl-N-2,3-dihydroxypropyl perfluorooctylsulfonamide 3.9 was used.
A test blade M was manufactured in the same manner as in Experiment A except that the weight was changed to parts by weight.

Experiment N: Nn-propyl-N-2,3-dihydroxypropyl perfluorooctylsulfonamide 3.3 was used with only 34.0 parts by weight of polyethylene glycol as the bifunctional curing agent.
A test blade N was manufactured in the same manner as in Experiment A except that the weight was changed to parts by weight.

Experiment O The polyurethane polymer was converted to an ether-based PPG-MDI (trade name: Vibracene B843, manufactured by Uniroyal) 100
Parts by weight of a bifunctional curing agent were changed to 2.3 parts by weight of ethylene glycol and 9.3 parts by weight of 1,6-hexanediol, and Nn-propyl-N-2,3-dihydroxypropyl perfluorooctylsulfonamide was used. A test blade O was prepared in the same manner as in Experiment A except that the weight was 2.9 parts by weight.
Was manufactured.

Experiment P The polyurethane polymer was converted to an ether-based PTMEG-HMD.
I (trade name Adiprene LW520, manufactured by Uniroyal)
A test blade P was manufactured in the same manner as in Experiment A, except that the amount was 100 parts by weight and N-n-propyl-N-2,3-dihydroxypropylperfluorooctylsulfonamide was 3.5 parts by weight.

Experiment Q The polyurethane polymer was an ester type EA-MDI (trade name: Coronate C4369, manufactured by Nippon Polyurethane).
0 parts by weight, 1.5 parts by weight of 1,4-butanediol, 5.9 parts by weight of 1,6-hexanediol and 1.5 parts by weight of a bifunctional curing agent, and a water repellency-imparting substance, trade name MF1 manufactured by Mitsubishi Materials Corporation
00 3.2 parts by weight, and after that, in the same manner as in Experiment A,
A test blade Q was manufactured.

Experiment R The polyurethane polymer was converted to an ester EA-MDI 10
The same procedure as in Experiment A was carried out except that the bifunctional curing agent was 1.6 parts by weight of 1,4-butanediol and 6.5 parts by weight of 1,6-hexanediol, and no water repellency-imparting substance was added to 0 parts by weight. The test blade R was manufactured.

Experiment S The polyurethane polymer was converted to an ester EA-MDI 10
0 parts by weight, 4.0 parts by weight of a bifunctional curing agent only with 1,4-butanediol, 1.0 parts by weight of a polyfunctional curing agent trimethylolpropane (trifunctional curing agent), and MF a water-repellent substance.
A test blade S was manufactured in the same manner as in Experiment A except that the amount was changed to 100 3.1 parts by weight.

Experiment T Experiment A was conducted except that the bifunctional curing agent was 5.8 parts by weight of only 1,4-butanediol and 1.4 parts by weight of the polyfunctional curing agent trimethylolpropane, and no water repellency-imparting substance was added. In the same manner as in the above, a test blade T was manufactured.

Experiment U The polyurethane polymer was converted to an ester EA-MDI 10
0 parts by weight, the bifunctional curing agent was 4.8 parts by weight of 1,4-butanediol alone, the polyfunctional curing agent was 1.2 parts by weight of trimethylolpropane, and the experiment A was repeated except that the water repellency-imparting substance was not added. Similarly, a test blade U was manufactured.

Experiment V A test blade V was manufactured by cutting a sheet material having a thickness of 0.7 mm in the same manner as in Experiment A, using G-655 (trade name) manufactured by Nippon Oil Seal Co., Ltd. as hydrogenated nitrile rubber.

Experiment W 100 parts by weight of SH861V as a silicone rubber and 100 parts by weight of Dow Corning Toray Co., Ltd. and R as a curing agent
C4, 2 parts by weight of Toray Dow Corning Co., Ltd. were mixed and press-molded with a mold to form a sheet material having a thickness of 0.7 mm. This was cut in the same manner as in Experimental Example A to produce a test blade W.

Each of the test blades A to W manufactured in each of the above Experiments A to W was attached to the ink jet recording apparatus shown in FIG. 9 and cleaned, and the surface roughness, the wear resistance, the head Evaluations were made on scratch resistance, ink pull-out properties, and obtained images.

Here, the ink jet recording apparatus used in the above-mentioned evaluation will be schematically described.

FIG. 9 is an external perspective view showing an example of an ink jet recording apparatus to which a blade is attached.

In the figure, reference numeral 501 denotes an ink jet head cartridge (IJC) provided with a nozzle group for discharging ink while facing a recording surface of a recording sheet sent on a platen 507. Reference numeral 502 denotes a carriage (HC) for holding the IJC 501, which is connected to a part of a drive belt 504 for transmitting the driving force of the drive motor 503, and is provided with two guide shafts 505 and 50 arranged in parallel with each other.
By being slidable with 6, the ink jet head can reciprocate over the entire width of the recording paper.

Reference numeral 508 denotes a head recovery device, which is an IJC5
01, for example, at a position facing the home position. The head recovery device 508 is operated by the driving force of the motor 510 via the transmission mechanism 509 to cap the IJC 501. IJC5 by the cap 511 of the head recovery device 508
01 in connection with capping to 01
08, ink is suctioned by an appropriate suction means provided in the ink jet printer, or ink is fed by an appropriate pressurizing means provided in an ink supply path to the IJC 501, thereby forcibly discharging the ink from the discharge port to increase the viscosity in the nozzle. An ejection recovery process such as removal of ink is performed. Also, by performing capping at the end of recording or the like, the recording head is protected.

Reference numeral 512 denotes a cleaning blade of the present invention disposed on the side of the head recovery device 508. The blade 512 is held in a cantilever form by a blade holding member 513 and, like the head recovery device 508, has a motor 5.
10 and the transmission mechanism 509, the IJC501
Can be engaged with the discharge surface. As a result, IJC5
01, at an appropriate timing in the printing operation, or after the ejection recovery processing using the head recovery device 508, the blade 512 is projected into the movement path of the IJC 501,
As the JC 501 moves, dew condensation, wetness, dust and the like on the ejection surface of the IJC 501 are wiped off.

For each test blade, JI
The rubber hardness in SA, the presence state of the water repellency-imparting substance, the ink contact angle, and the ink deterioration were evaluated.

The following briefly describes the evaluation method for each of the above evaluation items. (1) Rubber hardness: Measured according to a rubber hardness measurement method specified in JIS (Japanese Industrial Standard) A. The results are shown in Table 1. (2) Existence of water repellency-imparting substance: When each test blade was cut, the cut surface was observed with a microscope. Regarding the obtained results, those in which the presence of the particle component of the water repellency-imparting substance was recognized as “particles” and those in which the presence of the particle component was not recognized were referred to as “compatible” in Table 1.
It was shown to. (3) Ink contact angle: manufactured test blades A to W
About C.I. I. A contact angle meter (trade name: CA-Z150, trade name) using a water-based ink (hereinafter referred to as ink used) having a composition of Mard Fusso 2 3 wt%, diethylene glycol 25 wt%, N-methyl-2-pyrrolidone 20 wt%, and water 52 wt%. (Manufactured by Kyowa Interface Science Co., Ltd.). The results are shown in Table 1. In Table 1,
The “initial” ink contact angle indicates a measurement result of an unused state after the production of the test blade. Further, the ink contact angle “after ink swelling” indicates a measurement result of a state where the test blade is immersed in the used ink for 10 days. (4) Deterioration of ink: Each test blade was immersed in the used ink for 3 months, and the components of the immersed ink were measured by gas chromatography (trade name: GC-9A, manufactured by Shimadzu Corporation). The component change with the ink before immersion was compared. Here, ◎ indicates that the deteriorated state was not confirmed, ○ indicates that the deteriorated state was not substantially confirmed, Δ indicates that the ink component changed but was not a problem in image formation, and Are evaluated as x, and the results are shown in Table 1.
It was shown to. (5) Roughening resistance and abrasion resistance: A test blade was attached to the ink jet recording apparatus shown in FIG. 9 under the conditions that the free length of the blade was 8 mm and the penetration amount into the head was 1.5 mm. Then, a sequence in which no empty ejection is issued to the cap and a cleaning operation is performed once after that is described as 1
When the process is repeated 0 times, a predetermined pattern is recorded on recording paper. This cycle was repeated until the number of cleanings reached 50,000. At this time, the cleaning speed was 150 mm / sec, and the linear pressure on the head surface of the blade was 5 g / cm.

After 50,000 times, each of the test blades was observed under a microscope.

Regarding the surface roughening resistance, a blade having no chipping at the edge portion of the blade and not having a roughened surface was evaluated as ◎. A slightly chipped portion was recognized, but no problem occurred in cleaning. Was evaluated as ○, a chipped part was observed and roughened, and slightly affected cleaning, and Δ was marked as a chipped part was observed and the surface was roughened and affected cleaning as ×. Are shown in Table 1.

Regarding the abrasion resistance, ◎ indicates that no abrasion was observed at the edge of the blade, and ○ indicates that abrasion was slightly observed but did not affect the cleaning, and abrasion was observed. Those that slightly affected the cleaning were evaluated as Δ, and those that were significantly worn and affected the cleaning were evaluated as X. The results are shown in Table 1. (6) Head scratch resistance and ink pull-out property: After the cleaning operation was repeated 50,000 times under the same conditions as described above, the vicinity of the discharge port on the discharge port surface of the recording head was observed with a microscope. Regarding the head scratch resistance, ヘ ッ ド indicates that no damage was observed on the discharge port surface of the recording head, も の indicates that there was substantially no damage and did not affect ink discharge, and 、 indicates damage However, those that slightly affected the ink discharge were evaluated as Δ, and those that were damaged and affected the ink discharge were evaluated as x, and the results are shown in Table 1.

Regarding the ink pull-out property, ◎ indicates that ink pull-out was not recognized, ○ indicates that ink pull-out was not substantially recognized, and Δ indicates that ink pull-out was recognized and slightly affected ink ejection. When the ink ejection was remarkably recognized and the ink ejection was affected, the result was evaluated as x, and the results are shown in Table 1. (7) Image evaluation: A test blade was attached to the ink jet recording apparatus shown in FIG. 9 under the conditions that the free length of the blade was 8 mm and the penetration amount into the head was 1.5 mm. Then, do not issue 50 idle discharges to the cap.
A predetermined pattern is recorded on recording paper when the sequence of performing the cleaning operation is repeated 10 times. By repeating this cycle, the number of times of cleaning is 10,000 times,
The recording state of the recording pattern at the time of 10,000 times and 100,000 times was visually observed. At this time, the cleaning speed is 150
mm / sec, the linear pressure against the head surface of the blade is 5 g
/ Cm.

◎ indicates that a good image was formed, ○ indicates that a substantially problem-free image was formed, and about one image was printed on about 1,000 sheets (non-ejection portion).
Were evaluated as Δ, and those in which a non-ejection portion was observed almost every time were evaluated as x. The results are shown in Table 1.

From the results shown in Table 1, the following was found. That is, (i) for the polyurethane prepolymer,
Blade materials made with only a bifunctional curing agent and with the addition of a water repellency-imparting material are good for any of the above evaluation criteria; (ii) among these blade materials, a polyurethane prepolymer The number of moles (OH / NC) of the active element of both the bifunctional curing agent and the water repellency-imparting substance with respect to the number of moles of isocyanate groups contained therein
A blade material made with a ratio of O) of about 0.80 or more and 1.05 or less, more preferably about 0.9 or more and 1.0 or less gives satisfactory results for all of the above evaluation items. And (iii) especially 0.1 to 20 parts by weight, more preferably 1 to 1 part by weight, based on 100 parts by weight of the total of the polyurethane prepolymer and the bifunctional curing agent.
A blade material prepared by adding a water repellency-imparting substance of 0 parts by weight or less gives extremely excellent results in all of the above-mentioned evaluation items.

In addition to the facts described above, it has been found that the compatibility of the existing state of the water repellency imparting substance in the blade material is a very important factor for the performance of the blade material.

[0113]

[Table 1]

[0114]

[Table 2]

[0115]

[Table 3]

[0116]

[Table 4]

Embodiment 1 Hereinafter, an embodiment of the present invention will be described.

In the present embodiment, a test blade A which showed an excellent effect as a blade material in the previous experiment and a test blade S which did not obtain a sufficient effect were used as shown in FIG.
These blades were attached to an inkjet apparatus capable of full-color recording shown in FIGS. 0 to 13, and a durability test in which cleaning was repeated 50,000 times was performed.

The outline of the full-color ink jet apparatus shown in FIGS. 10 to 13 and the state of cleaning will be briefly described below in order.

In these figures, the head unit 10
1 is fixed to a carriage 102, and the carriage 102 is mounted on the main scanning rail 103 so as to be movable in the printing direction. For example, when clogging occurs in the ejection port 101b of the head unit 101, the holder 301 having the cap 300 that forms a closed space in the head moves in the direction of arrow a at the non-printing position, and the cap 300 moves to the ejection surface 101a. Stops at a position where a closed shape can be formed. In this state, suction recovery is performed by the pump unit 303 via the tube 302. The ink drawn from the head unit 101 by suction is conveyed to the ink discharge processing member 305 via the tube 304. After the suction recovery, the cap 30
The holder 301 having 0 is retracted in the direction of arrow b. At this time, the ink I drawn out from the discharge port 101b by the suction recovery remains on the discharge surface 101a of the head unit 101. Here, the carriage 102 moves, and the wiping of the ejection surface 101a is performed by the cleaning blade 401 held by the blade holder 402 (the state shown in FIGS. 11 and 12).
01a.

On the downstream side of the wiping of the head unit 101, the absorbers 104 are fixed to the head unit 101 one by one by means of bonding or thermal caulking. In the configuration on the head side, the absorber 104
A taper portion 101c is formed in a portion of the discharge surface 101a adjacent to the nozzle and located on the upstream side of the wiping by the absorber 104, so that the edge of the absorber 104 protrudes.

Further, the ink that may be slightly left on the blade 401 is absorbed by the absorber 105 as the second absorbing member provided on the carriage 102 so that the cleaning is completely performed.

The material of the absorbers 104 and 105 is a polyolefin-based porous material that hardly swells when absorbing liquid (for example, a material obtained by subjecting a porous sintered body of polyethylene to a hydrophilic treatment). And the swelling ratio is 0.0
1 to 0.02%. Product Name: Sunfine A
Q, manufactured by Asahi Kasei Corporation).

More specifically, referring to FIGS. 11 and 12, the ink I adhered to the ejection surface 101a by the suction recovery causes the blade 401 to move as the carriage 102 moves.
Is removed from the ejection surface 101a by the
At the same time, the ink I is scraped from the blade 401 by moving along the ejection surface 101a and coming into contact with the edge 104a of the absorber 104 of the head at the tapered portion 101c formed on the ejection surface 101a, and once the ink I is applied to the tapered portion 101c. Collect ink. Then, the ink I 'is immediately absorbed by the absorber 104 (the state of I' in FIG. 11). When the carriage 102 further moves, the blade 4
01 then moves by rubbing against the absorber 105 of the carriage. At this time, the blade 401 is attached to the absorber 104 of the head.
The small amount of ink I ″ that could not be removed by
When it arrives at the next head, the ink is completely removed from the edge 401a of the blade 401 (the state of FIG. 12). Therefore, the ejection surface 101a
The ink removed from the ink does not affect the next head, prevents color mixing, etc.
01a can always perform the next wiping in a pure state.

The edge states of the test blades A and S after the durability test were observed. As a result, the blade A manufactured using only the bifunctional curing agent and the water repellency-imparting material is not roughened at all (FIG. 4A), and can maintain a very good cleaning state for a long time without wear. FIG.
(A), FIG. 7 (a)), there is no deterioration in image quality. on the other hand,
The blade S manufactured by adding a large amount of the trifunctional curing agent is remarkably chipped off and roughened (FIG. 4).
(B)), the head surface is damaged, ink is slipped off or ink is drawn out (FIG. 5 (b)).
The cleaning property over a long period could not be maintained at all, and the image quality was deteriorated.

[0126]

As described above, the discharge head of the recording head can be obtained by using a material prepared by adding a bifunctional curing agent and a water repellency-imparting substance to a polyurethane to which no inorganic filler or the like is added. Without damaging the exit surface,
There is no alteration to the ink, the blade material itself is not easily worn, and it is extremely durable against roughening such as partial chipping of the material, and the ink repellency of the blade is maintained because water repellency is maintained. For this reason, it is possible to provide a cleaning blade exhibiting extremely stable cleaning characteristics even when used for a long time without causing ink draw-out.

By using a cleaning blade having such characteristics, an ink jet apparatus capable of high-speed recording or full-color recording capable of recording high-quality images stably for a long period of time can be provided with high reliability.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a state of cleaning by a cleaning blade in an ink jet recording apparatus that performs color recording.

FIG. 2 is an explanatory diagram illustrating a state in which an edge portion of a cleaning blade enters an ejection port of a recording head and pulls out ink.

FIG. 3 is an explanatory diagram illustrating a state in which ink is drawn from an ejection port of a recording head when an edge portion of a cleaning blade is satisfactorily worn.

FIG. 4 is an explanatory view showing a blade form after durability.
(A) shows a blade with excellent surface roughness, and (b) shows a blade with low surface roughening resistance.

FIG. 5A shows a good cleaning state,
FIG. 4B is an explanatory diagram illustrating a state in which ink is drawn from the ejection port by cleaning.

FIG. 6 is a diagram showing a relationship between a contact angle of a blade material and an ink adhering area.

FIGS. 7A and 7B are schematic diagrams respectively showing a state in which an adhered substance such as ink adheres to a discharge port surface.

FIG. 8A shows a state where good cleaning has been performed,
(B) is a schematic diagram showing a state where cleaning has been performed by a roughened blade.

FIG. 9 is an external perspective view showing an example of an ink jet recording apparatus provided with a cleaning blade to which the present invention is applied.

FIGS. 10A and 10B are schematic views sequentially illustrating blade cleaning in an ink jet recording apparatus in which color recording is performed, and show an initial state.

FIG. 11 is a second schematic diagram showing, in order, blade cleaning in an ink jet recording apparatus in which color recording is performed, and shows a state in which ink is absorbed by an absorber of a head.

FIG. 12 is a third schematic diagram showing, in order, blade cleaning in an ink jet recording apparatus in which color recording is performed, and shows a state in which ink is sucked into an absorber of a carriage.

FIG. 13 is a fourth schematic diagram showing, in order, blade cleaning in the ink jet recording apparatus for performing color recording, in a state where blade cleaning has been completed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink jet head 1a Discharge port surface 1b Ink discharge port 2 Main scanning carriage 3 Main scanning rail 4 Cleaning blade 5 Blade holder 6 Ink absorber

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Haruo Uchida 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hiroshi Taka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon (72) Inventor Atsushi Arai 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (58) Field surveyed (Int.Cl. ⁶ , DB name) B41J 2/165 B41J 2/01

Claims (16)

(57) [Claims] 1. A cleaning member for removing deposits adhered to an ink ejection surface of an ink jet recording head which ejects ink to perform recording on a recording medium, wherein the cleaning member is made of an ether-based polyurethane rubber elastic material. A cleaning member for an inkjet recording head, wherein the curing agent component of the ether-based polyurethane rubber elastic body is composed of only bifunctional components. 2. The cleaning member according to claim 1, wherein the bifunctional curing agent component is a linear diol. 3. The ink according to claim 1, wherein the ink is a water-based ink.
A cleaning member according to claim 1. 4. The cleaning member according to claim 1, wherein an ink contact angle on a surface of the cleaning member is 80 degrees or more. 5. The method according to claim 1, wherein the number of moles of the isocyanate group contained in the ether-based polyurethane rubber elastic material is 2.
The cleaning member according to claim 1, wherein the number of moles of the active element of the functional curing agent is 0.8 or more and 1.05 or less. 6. A recording head according to an ink jet recording method in which droplets are ejected from an ejection element using thermal energy to perform recording, and have an electrothermal converter as a means for generating thermal energy. The cleaning member according to claim 1, wherein 7. A cleaning member for removing an attached matter on an ink ejection surface of an ink jet recording head for ejecting ink to perform recording on a recording medium, wherein the cleaning member is made of a polyurethane rubber elastic material, and A cleaning member for an ink jet recording apparatus, wherein a curing agent component of a polyurethane rubber elastic body is composed of only a bifunctional component, and further contains a water repellency-imparting substance having an active group capable of chemically bonding to the polyurethane rubber. . 8. The cleaning member according to claim 7, wherein the water repellency-imparting substance is contained in the polyurethane rubber in a compatible state. 9. The ink according to claim 7, wherein the ink is an aqueous ink.
A cleaning member according to claim 1. 10. The cleaning member according to claim 7, wherein the recording head is of an ink jet recording type in which droplets are ejected from ejection elements using thermal energy to perform recording. 11. The cleaning member according to claim 7, wherein the water-repellent substance is a fluorine compound. 12. The cleaning member according to claim 7, wherein the water repellency-imparting substance is added in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the total of the polyurethane rubber raw material and the bifunctional curing agent. 13. The sum of the number of moles of the active element of the bifunctional curing agent and the water repellency-imparting substance to the mole number of the isocyanate group contained in the polyurethane rubber raw material is 0.8 or more. The cleaning member according to claim 7, wherein the cleaning member is not more than 05. 14. The cleaning member according to claim 7, wherein an ink contact angle on a surface of the cleaning member is 80 degrees or more. 15. An ink jet apparatus comprising a support member capable of mounting an ink jet head for performing recording on a recording medium by discharging water-based ink, wherein the support member comprises:
Means for scanning between a recording area in which the recording medium is conveyed and a non-recording area outside the area, and a cleaning blade capable of cleaning the ejection surface of the head in the non-recording area. Wherein the cleaning blade is made of an ether-based polyurethane rubber elastic body, and the curing agent component of the ether-based polyurethane rubber elastic body is composed of only bifunctional components. 16. An ink jet apparatus comprising a support member on which an ink jet head for discharging an aqueous ink to perform recording on a recording medium can be mounted.
Means for scanning between a recording area in which the recording medium is conveyed and a non-recording area outside the recording area, and a cleaning blade capable of cleaning the ejection surface of the head in the non-recording area. The cleaning blade is made of a polyurethane rubber elastic material, and the curing agent component of the polyurethane rubber elastic material is composed of only a bifunctional component, and further has a water repellency having an active group capable of chemically bonding to the polyurethane rubber. An ink jet device comprising a substance.