WO2010109755A1

WO2010109755A1 - Cleaning system

Info

Publication number: WO2010109755A1
Application number: PCT/JP2010/000916
Authority: WO
Inventors: 太田雅史; 永瀬貴行; 新居俊男; 松本英樹
Original assignee: バンドー化学株式会社
Priority date: 2009-03-23
Filing date: 2010-02-15
Publication date: 2010-09-30
Also published as: KR20140099947A; TWI483789B; CN102361703A; JP5605813B2; KR101523693B1; KR20120004420A; TW201036715A; JPWO2010109755A1

Abstract

Foreign materials can be continuously attracted by means of a cleaning roller for a relatively long period of time without requiring maintenance. A cleaning roller (11) is brought into contact with the surface (S1) of a material to be cleaned (S), and the foreign materials, such as dusts, which are adhered on the surface (S1) of the material to be cleaned (S) are removed using an electrostatic force. A transfer roller (51) is provided on the cleaning roller (11) surface on the reverse side of the surface having the material to be cleaned (S) thereon, and the foreign materials adhered on the cleaning roller (11) are transferred onto the transfer roller (51). An electrostatic charge control roller (21) which rotates in contact with the outer circumferential surface of the cleaning roller (11) is provided, and the electrostatic charge quantity of an outer layer section (11c) of the cleaning roller (11) can be controlled. As a material for forming the outer layer section of the transfer roller (51), a material which can be charged with electrostatic charges that can attract the foreign materials adhered on the outer circumferential surface of the cleaning roller (11) to the outer circumferential surface by means of an electrostatic force is selected.

Description

Cleaning system

The present invention relates to a cleaning system for removing foreign matters (dust etc.) adhering to the surface of a material to be cleaned. It is particularly suitable when the material to be cleaned is a thin object such as a film, a sheet, or a printed board.

Conventionally, as a cleaning system that removes foreign substances such as dust adhering to the surface of thin materials to be cleaned such as glass substrates of flat panel displays (FPD) and bonded films, adhesive rollers have been used and their adhesive strength is utilized. Thus, there is known one that removes the foreign matter (see, for example, Patent Document 1).

Such an adhesive roller cannot remove foreign matters having an average diameter of 1 μm or less, and it is difficult to completely remove foreign matters such as dust once adhering to the surface (adhesive layer) of the adhesive roller. Inferior. In addition, the adhesive roller is pressed against the material to be cleaned to a certain extent to remove foreign matter. If the material to be cleaned is, for example, a film, not only the foreign matter but also the film may stick to the roller surface. There is.

Therefore, the inventor applied electrophotographic technology to remove foreign matters such as dust from the material to be cleaned, a charge that can adsorb the foreign matter to the outer peripheral surface of the cleaning roller by electrostatic force due to peeling charging (or contact charging). Has been filed separately (see Japanese Patent Application No. 2008-271797) based on the fact that the foreign matter can be removed using electrostatic force by the cleaning roller.

JP 2008-168188 A (paragraph 0014)

However, in the above-described method, in order to charge a voltage capable of attracting the foreign matter to the outer peripheral surface of the cleaning roller by electrostatic force due to contact peeling between the cleaning material and the cleaning roller, the cleaning is performed according to the cleaning material. It is necessary to determine the material of the outer layer of the roller.

Therefore, the inventor further advances the one for which the patent application has been separately filed, and positively controls the charging of the cleaning roller using a charge control roller or an external power source, and the outer peripheral surface of the cleaning roller It was conceived that the foreign object can be stably adsorbed and removed from the material to be cleaned over a long period of time if the charged voltage capable of adsorbing the foreign object by electrostatic force is stably maintained. It is what.

An object of the present invention is to provide a cleaning system that can stably perform foreign matter adsorption operation by a cleaning roller over a long period of time.

According to a first aspect of the present invention, the cleaning roller includes a cleaning roller that moves while rotating while being in contact with the surface of the cleaning material, and the cleaning roller uses electrostatic force to remove foreign matters such as dust adhering to the surface of the cleaning material. The cleaning roller is capable of charging the outer peripheral surface with an electric charge that adsorbs foreign matter adhering to the surface of the material to be cleaned by electrostatic force. A charge control roller that rotates while being in contact with the outer peripheral surface of the cleaning roller is provided, and the charge control roller generates an electric charge for adsorbing foreign matter adhering on the surface of the cleaning material by electrostatic force to the cleaning roller. It is characterized in that it can be charged.

According to this configuration, due to contact peeling caused by rotation of the cleaning roller and the charge control roller, a charge for adsorbing foreign matter adhering to the surface of the cleaning material by electrostatic force is charged, and the cleaning roller is subjected to the cleaning. The cleaning roller is stably charged over a long period of time by the charge control roller that rotates while contacting the outer peripheral surface of the roller. As a result, the cleaning roller adsorbs the foreign matter adhering to the surface of the material to be cleaned by electrostatic force, and removes the foreign material from the surface of the material to be cleaned. Therefore, cleaning with the cleaning roller can be performed over a long period of time.

Even with the same cleaning roller, by changing the charge control roller (that is, by changing the combination of the cleaning roller and the charge control roller), the positive charge can be charged on the outer peripheral surface of the cleaning roller. Depending on the type of foreign matter adhering to the surface of the material to be cleaned (including the case of foreign matter of the same material and different charge polarity) Cleaning can be performed.

Furthermore, if a voltage having the same sign as the charge (positive charge or negative charge) charged to the cleaning roller is applied to the charge control roller by an external power source (for example, a high voltage power source), the charging property of the cleaning roller is applied. It is possible to raise the voltage according to the applied voltage, and it is possible to realize the adsorption and removal of foreign matters more efficiently by the cleaning roller.

In this case, for example, as described in claim 2, the charge control roller rotates while contacting the surface of the cleaning roller, so that the charge control roller and the cleaning roller are between the cleaning roller and the cleaning roller. A potential difference can be generated according to the difference in surface characteristics.

In this case, due to contact peeling due to the rotation of the cleaning roller and the charge control roller, the voltage of the cleaning roller is determined based on the surface characteristics of the charge control roller (for example, the charge control roller) based on the voltage of the charge control roller. A charge is generated that generates a potential difference according to the difference in the order), and charges for adsorbing foreign matter adhering to the surface of the material to be cleaned by electrostatic force are charged.

The transfer roller is provided so as to rotate while contacting the cleaning roller with respect to the cleaning roller. The transfer roller includes a conductive core rod and an outer side of the core rod. The elastic layer portion has a volume resistivity higher than that of the core rod, and is charged with a charge that adsorbs foreign matter adhering to the outer peripheral surface of the cleaning roller to the surface by electrostatic force. It is desirable to be formed from a material that can be used.

In this way, the foreign matter adsorbed by the electrostatic force on the outer peripheral surface of the cleaning roller comes into contact with the outer peripheral surface (surface) of the transfer roller by the rotation of the cleaning roller. Due to this contact, the elastic layer portion of the transfer roller is formed of a material that can charge the foreign matter adhering to the outer peripheral surface of the cleaning roller by electrostatic force, so that the foreign matter leaves the cleaning roller. Transferred to the transfer roller.

As described above, the foreign matter removed from the surface of the material to be cleaned by the cleaning roller is transferred to the transfer roller, and the foreign matter is not returned to the surface of the material to be cleaned. Further, since the foreign matter on the outer peripheral surface of the cleaning roller is constantly transferred to the transfer roller side, the foreign matter adhering to the outer peripheral surface of the cleaning roller is periodically removed (cleaned) or the foreign matter is attached. There is no need to perform maintenance work for periodically replacing the cleaning roller. Therefore, the foreign matter suction operation by the cleaning roller can be continuously performed over a long period of time.

The guide roller is disposed on the opposite side of the cleaning roller with the material to be cleaned interposed therebetween, and the cleaning roller adheres to the surface of the material to be cleaned. It is also possible to increase the electric field strength for adsorbing foreign matter by electrostatic force.

In this way, the two rollers (cleaning roller and guide roller) are opposed to each other with the material to be cleaned interposed therebetween, and the material to be cleaned is supported from above and below at the position where the cleaning roller and the guide roller are in contact with each other. The foreign matter is removed while being well supported.

In addition, the guide roller increases the electric field strength for adsorbing foreign matter adhering to the surface of the material to be cleaned by electrostatic force, and the charged foreign matter on the material to be cleaned depends on the applied electric field strength. Adsorbed to the cleaning roller and efficiently removed.

The cleaning roller includes a conductive core rod, a cylindrical inner layer portion provided outside the core rod, and an outer layer portion provided outside the inner layer portion. The outer layer portion preferably has a hardness (JIS-A) of 50 ° or more and has a higher volume resistivity than the inner layer portion. Here, “the volume resistivity is high” means that the electric resistance is high. Further, the hardness of the outer layer portion is measured using a flat plate having a thickness of 2 mm molded from the material forming the outer layer portion. The hardness of the outer layer part (JIS-A) is more preferably 60 ° or more.

In this way, since the outer layer portion has a hardness of 50 ° or more (JIS-A), the roller surface hardness can be increased, and since the outer layer portion has a higher volume resistivity than the inner layer portion, This is effective for maintaining a charged voltage generated by contact peeling with an object in contact with it, and can charge the outer peripheral surface with a charge that adsorbs foreign matter adhering to the surface of the material to be cleaned by electrostatic force.

Therefore, unlike the conventional adhesive roller, even if the material to be cleaned is a thin object such as a film, it is possible to prevent the material to be cleaned from being wound around the cleaning roller while maintaining the nip width.

As described in claim 6, the cleaning roller may be configured such that the inner layer portion is formed of an elastic material having conductivity and the outer layer portion is formed of acrylic mixed urethane or fluorine mixed urethane.

In this way, the charging polarity can be changed compared to the case where only urethane is used for the outer peripheral surface of the roller. Foreign substances that are easily charged negatively with acrylic mixed urethane are charged positively with fluorine mixed urethane. The foreign matters that are likely to be removed are easily removed from the material to be cleaned.

The transfer roller that rotates while contacting the surface of the cleaning roller is provided with respect to the cleaning roller, and the charging control roller is configured such that a first external power source is connected to a metal core. The charge for adsorbing foreign matter adhering to the surface of the cleaning material by electrostatic force can be changed with respect to the cleaning roller, and the transfer roller can remove foreign matter adhering to the surface of the cleaning roller by electrostatic force. It is also possible to use a first external power source connected to the core of the charge control roller to change the charge for adsorbing foreign matter by electrostatic force. Is possible.

In this way, the charge control roller can set a charge for adsorbing foreign matter adhering to the surface of the cleaning material by electrostatic force to the cleaning roller. Charges for adsorbing foreign matter adhering to the surface of the cleaning material by electrostatic force can be stably charged to the cleaning roller. As a result, the cleaning roller has a stable adsorbing force for adsorbing foreign matter adhering to the surface of the material to be cleaned by electrostatic force.

In addition, a transfer roller is provided so as to rotate with respect to the cleaning roller while being in contact with the cleaning roller, and the transfer roller charges the surface with a charge that adsorbs foreign matter adhering to the surface of the cleaning roller by electrostatic force. Since the foreign matter adsorbed by the electrostatic force on the surface of the cleaning roller comes into contact with the surface of the transfer roller by the rotation of the cleaning roller, the foreign matter leaves the cleaning roller and the transfer roller. Transferred to the surface. In this way, the foreign matter removed from the surface of the material to be cleaned by the cleaning roller is sequentially transferred to the transfer roller and does not remain on the surface of the cleaning roller, so that the foreign matter is returned to the surface of the material to be cleaned. It is not.

Further, since no foreign matter remains on the surface of the cleaning roller and the foreign matter is not returned to the surface of the cleaning target material, the foreign matter adhering to the roller surface of the cleaning roller is periodically removed (cleaned). In other words, it is not necessary to perform a maintenance work of periodically replacing the cleaning roller to which the foreign matter is adhered.

In addition, by applying a voltage from the first external power source connected to the core of the charge control roller, a voltage having a large absolute value is applied to the charge control roller with a sign opposite to the charge charged on the surface of the transfer roller during cleaning. By applying, the charging property of the transfer roller can be reversed, the adsorbing force of the foreign matter adsorbed on the transfer roller can be eliminated, and the foreign matter from the transfer roller can be easily removed. Here, “cleaning time” refers to a time when the cleaning roller rotates and moves relative to the surface of the material to be cleaned.

According to an eighth aspect of the present invention, the cleaning roller includes a cleaning roller that moves while rotating while being in contact with the surface of the material to be cleaned. The cleaning roller is connected to a first external power source and can charge the surface with a charge for adsorbing foreign matter adhering on the surface of the material to be cleaned by electrostatic force. A transfer roller that rotates while contacting the surface of the cleaning roller is provided with respect to the cleaning roller, and the transfer roller absorbs foreign matter adhering to the surface of the cleaning roller by electrostatic force. Can be charged on the surface and connected to the cleaning roller By changing the voltage applied by the first external source, the transfer roller, and wherein the said foreign object can change the charged voltage for adsorbing by electrostatic force.

In this way, the cleaning roller can charge the surface with a charge for adsorbing foreign matter adhering on the surface of the material to be cleaned by electrostatic force. Adsorbed to the cleaning roller. Further, since the transfer roller can charge the surface with a charge for adsorbing foreign matter adhering on the surface of the cleaning roller by electrostatic force, the foreign matter adsorbed on the cleaning roller is adsorbed on the transfer roller. Therefore, it is not necessary to perform maintenance work such as periodically removing (cleaning) or periodically replacing the cleaning roller.

In addition, by changing the voltage applied by the first external power source connected to the cleaning roller, it is possible to change the charged voltage of the transfer roller for attracting the foreign matter by electrostatic force. By changing the voltage applied by the external power source, it is possible to weaken the attractive force of the transfer roller with respect to the foreign matter adsorbed on the transfer roller. For example, by setting the polarity of the charged voltage of the transfer roller to a polarity opposite to the polarity in order to adsorb foreign matter adhering to the surface of the transfer roller by electrostatic force, the foreign matter adsorbed on the transfer roller The transfer roller can lose the attracting force. As a result, the above-described maintenance work for the transfer roller is facilitated.

Therefore, as in the conventional cleaning system that uses the adhesive force of the adhesive roller, the foreign matter adhering to the roller surface of the cleaning roller is periodically removed (cleaned) or the cleaning roller to which the foreign matter is attached is removed. There is no need to perform maintenance work for periodic replacement, and a cleaning system with excellent maintainability can be obtained. In addition, since the transfer roller can be easily maintained as described above, it is excellent in maintainability from this point.

In this case, as described in claim 9, the transfer roller rotates while contacting the surface of the cleaning roller, so that the surface characteristics of the transfer roller and the cleaning roller are between the cleaning roller and the surface. It is desirable to generate a potential difference according to the difference (for example, charging order).

In this case, due to contact peeling due to rotation of the cleaning roller and the transfer roller, a potential difference corresponding to a difference in surface characteristics (for example, charging sequence) from the cleaning roller is generated in the transfer roller, and the surface of the material to be cleaned A charge for adsorbing foreign matter adhering to the surface by electrostatic force is charged.

In addition, according to a tenth aspect of the present invention, a cleaning brush that rotates in a direction opposite to the rotation direction is provided for the transfer roller, and a metal roller is installed to rotate in the rotation direction with respect to the cleaning brush. The metal roller is connected to a second external power source, and is configured to generate a potential difference with the transfer roller. The metal roller adheres on the surface of the metal roller in the vicinity of the surface of the metal roller. It is desirable to have a configuration in which a cleaning blade that scrapes off foreign matter at the tip scraping portion is disposed.

In this way, the foreign matter removed from the transfer roller by the cleaning brush and adsorbed to the surface of the metal roller by electrostatic force is scraped off by the tip scraping part of the cleaning blade, and the foreign matter is removed from the surface of the metal roller. It is. In particular, the foreign matter can be more efficiently removed from the transfer roller by eliminating the adsorption force of the transfer roller to the foreign matter by controlling the voltage applied to the charging control roller.

12. The absolute value of the first external power source is an opposite sign to the charge charged on the surface of the transfer roller during the transfer operation by the transfer roller, except during cleaning by the cleaning roller. The second external power source has the same sign as the charge charged on the surface of the transfer roller during cleaning so as to generate a potential difference with the transfer roller. It is desirable that the potential is applied to the metal roller.

This arrangement is advantageous in removing foreign matter because the attracting force against foreign matter attracted to the surface of the transfer roller by electrostatic force is weakened by controlling the voltage applied to the charging control roller.

As described in claim 12, it is desirable that a suction port of air vacuum means capable of sucking foreign matter by negative pressure is provided in the vicinity of the surface of the metal roller.

In this way, the foreign matter adsorbed by the electrostatic force on the surface of the metal roller is sucked and removed through the suction port of the air vacuum means that can be sucked by the negative pressure.

Further, according to the thirteenth aspect of the present invention, a cleaning brush that rotates in a direction opposite to the rotation direction is provided for the transfer roller, and a metal roller is installed to rotate in the rotation direction with respect to the cleaning brush. The metal roller is connected to a second external power source, and is configured to generate a potential difference with the transfer roller. The metal roller adheres on the surface of the metal roller in the vicinity of the surface of the metal roller. It is desirable to arrange a cleaning blade that scrapes off foreign matter at the tip scraping portion.

In this way, foreign substances are removed from the transfer roller by the cleaning brush, transferred to the metal roller by electrostatic force, and scraped off by the tip scraping part of the cleaning blade. And since the foreign material adsorbed by the electrostatic force on the surface of the metal roller is scraped off by the tip scraping part of the cleaning blade, the foreign material is efficiently removed from the metal roller. In particular, when the voltage applied by the second external power source is changed and the metal roller loses the attractive force to the foreign matter adsorbed thereto, the foreign matter is more efficiently removed from the metal roller.

Further, as described in claim 14, it is preferable that a suction port of an air vacuum means capable of sucking foreign matter by negative pressure is disposed in the vicinity of the cleaning blade installed on the surface of the transfer roller.

According to this configuration, the foreign matter adsorbed by the electrostatic force on the surface of the transfer roller is scraped off by the tip scraping portion of the cleaning blade, and the foreign matter is sucked by the negative pressure through the suction port of the air vacuum means. Therefore, there is no possibility that the foreign matter will contaminate the periphery of the transfer roller.

The guide roller is disposed on the opposite side of the cleaning roller with the cleaning material interposed therebetween, and the cleaning roller adheres to the surface of the cleaning material. The electric field strength for adsorbing foreign matter by electrostatic force can be increased.

Furthermore, as described in claim 16, the charging control roller can be provided not on the cleaning roller but on the continuous roller. That is, the invention of claim includes a cleaning roller that moves relative to the surface of the material to be cleaned while rotating, and removes foreign matter such as dust adhering to the surface of the material to be cleaned by the electrostatic force by the cleaning roller. The cleaning roller is capable of charging the surface with a charge that adsorbs foreign matter adhering to the surface of the material to be cleaned by electrostatic force. A transfer roller that rotates while contacting the surface of the roller is provided, and the transfer roller is formed of a material capable of charging the surface with a charge that adsorbs foreign matter adhering to the surface of the cleaning roller by electrostatic force, and the transfer roller Against the surface of the transfer roller. The charge control roller is connected to a first external power source to a core metal, and the charge for adsorbing foreign matter adhering on the surface of the material to be cleaned by electrostatic force is used as the cleaning roller. The transfer roller can be changed.

In this case, since the charge control roller is provided for the transfer roller, when the second external power source described above is provided, the current generated by the second external power source is prevented from flowing into the cleaning roller. Even if the material to be cleaned is a conductive material or the like, electrical damage to the material to be cleaned can be prevented.

The present invention can stably charge the cleaning roller for a long period of time with a charge for adsorbing foreign matter adhering to the surface of the material to be cleaned by electrostatic force.

Therefore, the cleaning roller can adsorb foreign matter adhering to the surface of the material to be cleaned by electrostatic force, and can stably remove the foreign matter from the surface of the material to be cleaned over a long period of time.

(A) (b) is a figure which shows one Embodiment of the cleaning unit used for the cleaning system which concerns on this invention, respectively. It is a figure which shows embodiment which has arrange | positioned the said cleaning unit 2 series. It is explanatory drawing which shows another embodiment of the cleaning unit which concerns on this invention. It is explanatory drawing which shows another embodiment of the cleaning unit which concerns on this invention. It is explanatory drawing of the foreign material removal test. It is a figure similar to Fig.1 (a) which shows other embodiment of a cleaning unit. It is a figure similar to FIG. 2 which shows embodiment which has arrange | positioned the cleaning unit of other embodiment 2 series. FIG. 10 is a view similar to FIG. 4 showing still another embodiment of the cleaning unit. It is a figure similar to FIG. 3 which shows another embodiment of a cleaning unit. It is explanatory drawing of the foreign material removal test. It is a figure which shows an example of the cleaning system which concerns on this invention. (A) (b) is explanatory drawing which shows the basic structure of the cleaning unit used for the cleaning system which concerns on this invention, respectively. It is a figure which shows embodiment of the said cleaning unit. It is a figure which shows embodiment which has arrange | positioned two cleaning units. It is a figure similar to FIG. 2 about another embodiment. It is a figure similar to FIG. 2 about another embodiment. It is explanatory drawing of a foreign material removal test. It is a figure which shows an example of the cleaning system which concerns on this invention. It is a figure which shows other embodiment of a cleaning unit. It is a figure which shows an example of the cleaning system using the cleaning unit shown in FIG. (A) (b) is explanatory drawing of the principle which removes foreign materials, such as dust, by an example of the cleaning unit used for the cleaning system which concerns on this invention, respectively, using electrostatic force. (A)-(f) is explanatory drawing of operation | movement of the said unit, respectively. It is a figure similar to Fig.1 (a) about another embodiment. It is a figure similar to Fig.1 (a) about another embodiment. It is explanatory drawing of a foreign material removal test. It is a figure which shows an example of the cleaning system which concerns on this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Basic embodiment)
As shown in FIG. 1A, the cleaning unit U used in the cleaning system according to the present invention includes a cleaning roller 11 that rotates and moves relative to the surface S1 of the material S to be cleaned. Foreign matter (not shown) such as dust adhering to the surface S1 of S is removed by the cleaning roller 11 using electrostatic force. This cleaning roller 11 is capable of charging the outer peripheral surface with a charge that adsorbs foreign matter adhering to the surface S1 of the material to be cleaned S by electrostatic force, and uses the charging property of the roller surface (outer peripheral surface) of this cleaning roller. Thus, foreign matter is adsorbed.

The cleaning roller 11 is provided with a charge control roller 21 that rotates while being in contact with the outer peripheral surface of the cleaning roller 11 to constitute one cleaning unit U. The charging control roller 21 can stably charge the outer peripheral surface (outer layer portion) of the cleaning roller 11 with a charge for adsorbing foreign matter adhering on the surface S1 of the cleaning material S by electrostatic force. is there.

The cleaning roller 11 is made of a metal core (core bar) 11a, a cylindrical inner layer portion 11b provided outside the metal core 11a, and a material having higher resistance than the inner layer portion 11b provided outside the inner layer portion 11b. A thin cylindrical outer layer portion 11c (for example, a thickness of about 30 μm), and has a two-layer structure.

As the material for forming the outer layer portion 11c of the cleaning roller 11, a material capable of charging a charge that adsorbs foreign matter such as dust adhering to the surface S1 of the material to be cleaned S by electrostatic force is selected. That is, it only needs to have a potential difference with respect to the charged voltage of the foreign matter, and it is appropriately charged positively or negatively by the charging control roller. Note that the charging control roller 21 stabilizes the charged voltage of the cleaning roller 11 regardless of the foreign material adhering to the cleaning target material S or the surface S1 thereof.

The thickness of the outer layer portion 11c of the cleaning roller 11 is preferably 2 to 500 μm (more preferably 5 to 50 μm). This is because if the thickness of the outer layer portion 11c is less than 2 μm, the roller surface (outer layer surface) tends to be less likely to be charged. On the other hand, the thickness exceeding 500 μm is not industrially efficient. In place of the cored bar 11a, a cored bar made of a conductive carbon material, synthetic resin composite, or the like can be used. The volume resistivity of the core rod is desirably 10 ⁵ Ωcm or less.

The inner layer portion 11b is made of a conductive elastic material (for example, polyester urethane containing carbon (conductive material)), and has a lower hardness or substantially the same hardness as the outer layer portion 11c. The inner layer portion 11b is not particularly limited as long as it has a lower resistance than the outer layer portion 11c, but the volume resistivity is preferably about 10 ⁴ to 10 ¹² Ωcm.

The material used for the outer layer portion 11c has a hardness (JIS-A) of 50 ° or more (desirably 50 ° or more and 100 ° or less, more desirably 55 ° or more and 100 ° or less, and further desirably 65 ° or more and 100 ° or less). . The outer layer portion 11c has a higher resistance than the inner layer portion 11b. The outer layer part 11c desirably has a volume resistivity of 10 ⁸ Ωcm or more, and more desirably 10 ¹⁰ Ωcm or more.

Preferred examples of the material forming the outer layer portion 11c of the cleaning roller 11 include urethane resin, and further, acrylic mixed urethane or fluorine mixed urethane. Here, the “acrylic mixed urethane” is mainly composed of polyester polyurethane or polyether polyurethane, and (i) a mixture of thermoplastic urethane resin and silicon / acrylic copolymer resin, (ii) acrylic resin (for example, methacrylic acid-methacrylic acid). A mixture consisting of a graft compound in which an aminoethyl group is grafted to the main chain consisting of an acid methyl copolymer) and a thermoplastic urethane resin, and (iii) a mixture consisting of an acrylic resin / urethane resin / fluorinated surface coating agent. The “fluorine-mixed urethane” is a polyurethane-based component, which means a mixture of a urethane / fluorine copolymer with a thermoplastic urethane resin.

The charging control roller 21 includes a conductive metal core 21a, a cylindrical inner layer portion 21b provided outside the metal core 21a, and a cylindrical outer layer portion 21c provided outside the inner layer portion 21b. The outer layer portion 21c is set to have a higher volume resistivity than the inner layer portion 21b. The cored bar 21a, the inner layer part 21b, and the outer layer part 21c of the charge control roller 21 can also be formed, for example, using a material that generates a potential difference according to the difference in surface characteristics from the cleaning roller 11. The charge control roller may have a structure in which a cylindrical outer layer portion 21c 'is directly provided outside the core metal 21a' as in the charge control roller 21 'shown in FIG. However, the material of the outer layer portions 21c and 21c ′ of the

charge control rollers

21 and 21 ′ is the contact between the cleaning roller 11 and the

charge control rollers

21 and 21 ′ due to the rotation of the cleaning roller 11 and the

charge control rollers

21 and 21 ′. It is desirable that the potential difference generated according to the difference in surface characteristics is as large as possible as long as the stable adsorptivity is not impaired.

The charge control roller 21 can charge the cleaning roller 11 with a charge that adsorbs foreign matter adhering to the surface S1 of the material to be cleaned S by electrostatic force. In the case shown in FIG. The cored bar 21a of the charge control roller 21 is set to a reference potential (for example, ground potential, that is, 0V).

The cleaning roller 11 that rotates with the charge control roller 21 is charged by contact peeling between the cleaning roller 11 and the charge control roller 21, and the surface characteristics of the cleaning roller 11 and the charge control roller 21 are changed between the cleaning roller 11 and the charge control roller 21. Depending on the difference, a potential difference is generated based on the charging sequence. Since the potential difference generated between these

rollers

11 and 21 is generated according to the difference in the surface characteristics thereof, a constant numerical value is stably displayed at a constant peripheral speed.

A value obtained by adding or subtracting the potential difference generated according to the difference in surface characteristics between the

rollers

11 and 21 to the potential of the charging control roller 21 according to the material forming the outer layer portions 11 c and 21 c is the value of the cleaning roller 11. It becomes a charged voltage. That is, if the material forming the outer layer portion 21c of the charge control roller 21 is positive with respect to the material forming the outer layer portion 11c of the cleaning roller 11, the cleaning roller 11 is charged to the negative side and the charging sequence is charged. If is negative, the cleaning roller 11 is charged positive.

For example, when the potential of the charging control roller 21 is 0 V as the ground potential and the potential difference generated according to the difference in surface characteristics between the

rollers

11 and 21 is 300 V, the charging voltage of the cleaning roller 11 is −300 V or +300 V. It becomes. Even when the cleaning roller 11 is the same, when the cleaning roller 11 exhibits a negative characteristic with respect to the charge control roller 21, −300 V is indicated, and when the cleaning roller 11 exhibits a positive characteristic with respect to the charge control roller 21. Will show + 300V.

Therefore, according to the cleaning roller 11, the cleaning roller 11 is stably charged with a charge capable of adsorbing foreign matter by electrostatic force due to contact with the charging control roller 21. The cleaning performance that foreign matters are removed from the surface S1 of the substrate is stably exhibited.

Further, as shown in FIG. 2, two cleaning units U1 and U2 are arranged, and in each of the units U1 and U2, the sign of the charge charged on the outer peripheral surface of the cleaning rollers 11A and 11B with respect to the cleaning rollers 11A and 11B. It is possible to provide charging control rollers 21A and 21B that can reverse the above. In this way, the cleaning roller 11A (cleaning unit U1) that negatively charges the positively charged foreign matter adhering to the surface S1 of the cleaning material S and the cleaning roller 11B (cleaning) that positively charges the negatively charged foreign matter. Each unit U2) can be removed, and the range of foreign matter that can be removed is increased.

Further, as shown in FIG. 3, a guide roller 41 may be disposed on the opposite side of the cleaning roller 11 with the material to be cleaned S interposed therebetween. The guide roller 41 is for increasing the electric field intensity for the cleaning roller 11 to adsorb foreign matter adhering to the surface of the material to be cleaned S by electrostatic force. The guide roller 41 is electrically conductive on the outer side of the core metal 41a. And an outer layer portion 41c having an insulating property on the outside of the inner layer portion 41b, and is formed to increase the electric field strength.

This guide roller 41 has a potential difference with respect to the cleaning roller 11, and is provided with another charge control roller 71 having the same structure as the charge control roller 21. The guide roller 41 allows the cleaning roller 11, the guide roller 41, and The electric field strength acting on the material to be cleaned S sandwiched between them can be stably increased further, and the cleaning property can be improved.

In this case, it is desirable to select the charging

control rollers

21 and 71 so that the potential of the guide roller 41 is higher than the potential of the cleaning roller 11 or vice versa. For example, when the

charge control rollers

21 and 71 are connected to the ground and both indicate 0 V, the potential difference generated with respect to the cleaning roller 11 and the guide roller 41 is 300 V, and the charge control roller 21 exhibits a positive characteristic. If the control roller 71 exhibits a negative characteristic, the outer peripheral surface of the cleaning roller 11 can be charged to −300V, and the outer peripheral surface of the guide roller 41 can be charged to + 300V. In this way, the two

rollers

11 and 41 are opposed to each other with the material to be cleaned S interposed therebetween, and a potential difference of 600 V is generated at the position where the material to be cleaned S contacts the cleaning roller 11 and the guide roller 41, thereby generating The strength is the highest, and charged foreign matter on the surface S1 of the cleaning material S is adsorbed to the outer peripheral surface of the cleaning roller 11 by electrostatic force according to the applied electric field, and effectively from the surface S1 of the cleaning material S. Removed.

Further, instead of the guide roller 41, another cleaning roller is disposed with the material to be cleaned S interposed therebetween, so that the front surface and the back surface (back surface) of the material to be cleaned S can be simultaneously cleaned. Also in this case, two units can be arranged similarly to the one shown in FIG. Needless to say, the cleaning material S may be cleaned only on the back surface side.

Further, as shown in FIG. 4, an external power source 31 (for example, a high voltage power source) can be connected to the cored bar 21a of the charging control roller 21. In this case, the reference potential of the charging control roller 21 can be set to a potential given by the voltage applied by the external power supply 31. For example, when −300 V is applied to the metal core 21a of the charging control roller 21 by the external power supply 31, the cleaning roller 11 shows a value obtained by adding −300 V to the potential difference generated when the ground potential is set as the reference potential. .

Next, the foreign matter removal test 1 performed using the above-described unit will be described.
(Test method)
As shown in FIG. 5, the charging control roller 21 and the cleaning roller 11 held by an insulating member (not shown) are brought into contact with each other and rotated together at a peripheral speed of 5 m / min. The core potential 21a was applied with a ground potential of 0 V or a voltage ± 500 V from an external power source. In the description of examples and comparative examples described later, a ground potential of 0 V is applied unless otherwise specified.

On the other hand, using a sample in which foreign matter (polystyrene resin or acrylic resin having an average diameter of 1 μm, 10 μm) is sprayed on the surface of a film-like material to be cleaned (PET film: 15 cm × 15 cm × 100 μm), the foreign matter of the cleaning roller The removal performance was evaluated.

In the evaluation experiment, five materials to be cleaned were continuously cleaned, and the first material to be cleaned was sample 1, the next was sample 2, and the samples up to sample 5 were evaluated. While the material to be cleaned was being cleaned, the surface potential of the cleaning roller 11 was measured using a surface potential meter 45 (Model 341B manufactured by Trek).
(Description of Examples and Comparative Examples)
The following Tables 1 and 2 show the roller structures of Examples and Comparative Examples in which the foreign matter removal test 1 was performed, and Table 3 shows the compositions of the inner and outer layers. The production methods of the rollers of Examples and Comparative Examples shown in Tables 1 and 2 are as follows. An inner layer portion (thickness 6 mm / width (dimension in the extension direction of the core metal) 240 mm) was formed on a metal core (material: aluminum alloy size: diameter φ28 mm × length 250 mm). For those having an outer layer portion, an outer layer portion (thickness 30 μm / width 240 mm) was further formed outside the inner layer portion. As a result, the elastic layer has an outer diameter of 40 mm and a width of 240 mm.

However, for the roller having no inner layer portion (the charge control rollers of Examples 9, 16, and 17 are applicable), the outer layer portion (thickness 30 μm / width 240 mm) was directly formed on the same core metal as described above.

(Test results)
Table 4 shows the test results when the foreign material is an acrylic resin, and Table 5 shows the test result when the foreign material is a polystyrene resin. Here, in the table, ○ marks indicate three points in the range of 650μm × 500μm using a digital microscope (Digital microscope VHX-200 KEYENCE, lens magnification 450 times). A case where no foreign matter is confirmed is indicated by a circle, and a case where a foreign object is confirmed is indicated by a cross.

In Examples 1 to 17 in which the charging control roller 21 is introduced, a potential difference is generated according to the difference in surface characteristics (for example, charging sequence) between the charging control roller 21 and the cleaning roller 11, so that the charging voltage of the cleaning roller 11 is stabilized. It can be seen that foreign matter has been removed in any sample, and stable cleaning performance can be obtained over a long period of time.

Further, for example, even if the cleaning roller 11 is the same as in the sixth embodiment and the fourteenth embodiment, the potential of the cleaning roller can be made negative or positive by changing the charging control roller 21. You can also see what you can do. In Comparative Example 4, the foreign matter was removed exclusively using the adhesive force, and although a 10 μm foreign matter could be removed, a finer 1 μm foreign matter could not be removed.

On the other hand, in Comparative Examples 1 to 8 in which the charging control roller is not introduced, the charging voltage of the cleaning roller 11 fluctuates and continuous stability cannot be obtained (see * in Tables 1 and 2). After the voltage continues to rise remarkably, the charged voltage varies due to discharge (arc discharge), and the roller charged voltage becomes positive or negative. That is, it is not possible to obtain continuous foreign matter adsorbability.

In the above-described embodiment, the charging control roller 21 is provided for the cleaning roller 11 that can charge the outer peripheral surface with a charge that adsorbs foreign matter adhering to the surface of the material to be cleaned by electrostatic force. As shown, in addition to the charge control roller 21, a transfer roller 51 that rotates while being in contact with the outer peripheral surface of the cleaning roller 11 may be provided to constitute a cleaning unit U10 with improved maintainability.

That is, by providing the transfer roller 51 in contact with the cleaning roller 11 on the opposite side to the cleaning material S of the cleaning roller 11, foreign matter adhering to the cleaning roller 11 due to electrostatic force is transferred to the transfer roller 21 side. (Move). As a result, the cleaning roller 11 comes into contact with the material to be cleaned S in a state where the foreign matter attached to the outer peripheral surface of the cleaning roller 11 is transferred to the transfer roller 21.

Similar to the cleaning roller 11, the transfer roller 51 includes a conductive metal core 51a, a cylindrical inner layer portion 51b provided outside the metal core 51a, and an outer layer portion provided outside the inner layer portion 51b. 51c (elastic layer portion), and the outer layer portion 51c may have a higher volume resistivity than the inner layer portion 51b. However, the transfer roller 51 may also have a structure in which the core 51a is directly provided with a cylindrical outer layer portion (elastic layer portion). Further, the outer layer portion 51c of the transfer roller 51 is selected to have a volume resistivity higher than that of the core metal 51a, and can charge the foreign matter adhering to the outer peripheral surface of the cleaning roller 11 to the outer peripheral surface by electrostatic force. The

The transfer roller 51 rotates with the cleaning roller 11 and is charged by contact peeling, and adheres to the outer peripheral surface of the cleaning roller 11 between the outer peripheral surface of the transfer roller 51 and the outer peripheral surface of the cleaning roller 11. A potential difference is generated so as to transfer (move) the foreign matter on the outer peripheral surface of the transfer roller 51 by electrostatic force. That is, the transfer roller 51 has the same sign as the charge (positive charge or negative charge) charged on the roller 11 and the absolute value of the charged voltage with respect to the cleaning roller 11 due to the difference in roller surface characteristics (for example, charging order). Is larger than the roller 11 and has a potential difference capable of adsorbing foreign matter. For this reason, as a material for forming the outer layer portion 51c of the transfer roller 51, a material having the same polarity as the cleaning roller 11 and a potential difference that is as large as possible is selected as long as stable adsorbability is not impaired. Is desirable.

If the charge amount of the cleaning roller 11 is constant, the charged voltage of the transfer roller 51 is determined according to the generated potential difference (potential difference corresponding to the difference in surface characteristics between the rollers 51 and 11). For example, if the cleaning roller 11 exhibits a voltage of −300V, the potential difference between the cleaning roller 11 and the transfer roller 51 is 300V, and the transfer roller 51 exhibits a negative characteristic, the transfer roller 51 has −600V. It will indicate the charged voltage.

The foreign matter transferred to the transfer roller 51 side due to the potential difference generated by the contact peeling between the cleaning roller 11 and the transfer roller 51 stops the rotation of the transfer roller 51, so that the transfer roller 51 itself loses the adsorptivity due to electrostatic force. Therefore, it can be removed from the transfer roller 51 relatively easily. Here, as a means for removing the foreign matter from the transfer roller 51, for example, wiping, brushing, scraping with a rubber blade, air blowing, or other appropriate means may be employed.

Therefore, the foreign matter adsorbed by the electrostatic force on the cleaning roller 11 is brought into contact with the transfer roller 51 by the rotation of the cleaning roller 11, so that a potential difference is generated between the transfer roller 51 and the cleaning roller 11. The roller 11 leaves the outer peripheral surface and is transferred (moved) to the outer peripheral surface of the transfer roller 51.

As a result, the foreign matter on the outer peripheral surface of the cleaning roller 11 is continuously transferred to the transfer roller 51 side, and the cleaning roller 11 is in a state where the cleaning effect can be exerted at any time. The adsorption operation can be continued. Therefore, maintenance work for periodically removing foreign matters on the outer peripheral surface of the cleaning roller 11 or replacing the cleaning roller 11 is not necessary, and the maintainability is improved.

Also in this case, as shown in FIG. 7, two cleaning units U11 and U12 are arranged, and the signs of the charges charged on the rollers 11A and 11B are given to the cleaning rollers 11A and 11B with which the transfer rollers 51A and 51B come into contact. The reverse charging control rollers 21A and 21B can be provided. The sign of the charge charged on the cleaning rollers 11A and 11B is also reversed so that the positively charged foreign matter adhering to the cleaning material S is negatively charged and the negatively charged foreign matter is positively charged by the cleaning roller 11A. Each can be removed by the roller 11B.

As shown in FIG. 8, the charging voltage of the cleaning roller 11 can be changed by changing the reference of the charging control roller 21 (0 V when grounding is used) by using an external power source 31. For example, when −300 V is applied to the charging control roller 21, the charging voltage of the cleaning roller 11 shows a value obtained by adding −300 V to the potential difference generated between the

rollers

21 and 11.

As shown in FIG. 9, a guide roller 41 may be disposed on the opposite side of the cleaning roller 11 with the material to be cleaned S interposed therebetween. This guide roller 41 increases the electric field strength for the cleaning roller 11 to adsorb foreign matter adhering to the surface of the material S to be cleaned by electrostatic force.

In this case, a charge control roller 71 is also provided for the guide roller 41, and the strength of the electric field acting on the cleaning material S sandwiched between the cleaning roller 11 and the guide roller 41 is further increased by the guide roller 41, thereby cleaning performance. Can be improved. For example, the charging voltage of the guide roller 41 can be set to +300 V by introducing a charge control roller 71 having a potential difference of 300 V and a negative characteristic with respect to the guide roller 41.

Of course, when the back surface of the material to be cleaned S needs to be cleaned, a cleaning roller can be provided instead of the guide roller 41. In this case, as shown by a chain line in FIG. 9, by introducing the transfer roller 72, it is possible to form a unit having a transfer mechanism on the back surface of the material S to be cleaned. A double arrangement can also be adopted.

Subsequently, the foreign matter removal test 2 using a transfer roller will be described.

(Test method)
The charging control roller 21 and the cleaning roller 11 held by an insulating member (not shown) are brought into contact with each other and rotated at a peripheral speed of 5 m / min. A voltage ± 500 V from an external power supply was applied. In the description of examples and comparative examples described later, a ground potential of 0 V is applied unless otherwise specified.

On the other hand, using a sample in which foreign matter (polystyrene resin or acrylic resin having an average diameter of 1 μm and 10 μm) is sprayed on a film-like material to be cleaned S (PET film: 15 cm × 15 cm × 100 μm), foreign matter removal from the cleaning roller is performed. Performance was evaluated. In the evaluation experiment, 10 sheets of the material to be cleaned were set to 1 cool, and 5 cools were continuously performed.

Further, the foreign matter adhered to the cleaning roller 11 after the cleaning was completed, and the foreign matter remaining on the transfer roller 51 after the transfer roller 51 was wiped off with a waste cloth containing water were confirmed.

The surface potentials of the cleaning roller 11 and the transfer roller 51 during cleaning were measured using surface potential meters 55 and 56 (Model 341B manufactured by Trek).

(Description of Examples and Comparative Examples)
The following Tables 6 and 7 show the roller structures of Examples and Comparative Examples in which the foreign matter removal test 2 was performed, and the compositions of the inner and outer layers are shown in Table 3. The production methods of the rollers of Examples and Comparative Examples shown in Tables 6 and 7 are the same as those in the foreign matter removal test 1 described above, and are made of a core metal (material: aluminum alloy, size: diameter φ28 mm × length 250 mm). The inner layer part (thickness 6 mm / width (dimension in the extension direction of the core metal) 240 mm) is molded, and those having the outer layer part further mold the outer layer part (thickness 30 μm / width 240 mm), and the elastic layer has the outer diameter The diameter was 40 mm and the width was 240 mm. For a roller having no inner layer portion (corresponding to the transfer roller of Example 20), an outer layer portion (thickness 30 μm / width 240 mm) was directly formed on the same cored bar as described above.

(Test results)
Table 8 shows the test results when the foreign material is an acrylic resin, and Table 9 shows the test result when the foreign material is a polystyrene resin.

Here, in Tables 8 and 9, as in the case of the foreign matter removal test 1, the circles indicate 650 μm × 500 μm using a digital microscope (digital microscope VHX-200 KEYENCE, lens magnification: 450 times). The range of 3 is confirmed, and a case where foreign matter is not confirmed at all points is indicated by a circle, and a case where foreign matter is confirmed is indicated by a cross.

In Examples 18 to 22 in which the charged voltage of the transfer roller 51 has the same polarity as the charged voltage of the cleaning roller 11 and the absolute value of the charged voltage of the transfer roller 51 is larger than the absolute value of the charged voltage of the cleaning roller 11 In this cool, the foreign matter adsorbed on the cleaning roller 11 is transferred to the transfer roller 51, and the cleaning effect is continuously exhibited.

On the other hand, even if the charging roller 51 has the same polarity as that of the cleaning roller 11, the absolute value of the charging roller 51 is smaller than the absolute value of the cleaning roller 11. In Comparative Example 12, in which the charging voltage of the transfer roller 51 is different from the charging voltage of the cleaning roller 11 and the cleaning roller 11, no foreign matter is transferred from the cleaning roller 11 to the transfer roller 51.

In Comparative Examples 11 and 13, a conventional adhesive roller is used as the transfer roller 51, and as described in the prior art section, 1 μm foreign matter cannot be transferred.

An example of the overall configuration of the cleaning system having the above-described cleaning unit will be described.

As shown in FIG. 11, the cleaning system 61 includes a cleaning unit 62 that removes foreign matter (conductor or dielectric) such as dust adhering to the surface S <b> 1 of the material S to be cleaned using electrostatic force, and the cleaning unit 62. A carrying-in unit 63 that conveys the material to be cleaned S toward the surface, and a carrying-out unit 64 that carries out the material to be cleaned S after cleaning from the cleaning unit 61.

The carry-in unit 63 is configured such that a conveyance belt 63C is wound around a pair of rollers 63A and 63B, and the material S to be cleaned on the conveyance belt 63C is conveyed toward the cleaning unit 62.

The carry-out unit 64 is configured so that the conveyance belt 64C is wound around the pair of rollers 64A and 64B, and the material to be cleaned S discharged from the cleaning unit 62 onto the conveyance belt 64C is conveyed in a direction away from the cleaning unit 62. It has become.

The cleaning unit 62 includes a pair of cleaning rollers 11A and 11B that rotate with the outer peripheral surface being in contact with the surface S1 (upper surface) of the material S to be cleaned. The charging control rollers 21A and 21B 21B and the outer peripheral surfaces of the transfer rollers 51A and 51B are rotated while being in contact with each other. In addition, a pair of cleaning rollers 11A ′ and 11B ′ are also arranged on the back surface (lower surface) of the material to be cleaned S corresponding to the upper cleaning rollers 11A and 11B, and between the cleaning rollers 11A and 11B. The cleaning material S is moved to the carry-out portion 64 side with the cleaning material S interposed therebetween. The cleaning rollers 11A 'and 11B' are also provided with transfer rollers 72A and 72B corresponding to the charge control rollers 71A and 71B. The rotational force of the drive roller 74 is transmitted to the shaft portions of the cleaning rollers 11A 'and 11B' via the drive belt 73, so that the cleaning rollers 11A 'and 11B' are rotationally driven.

(First specific embodiment)
As shown in FIG. 12A, the cleaning unit U used in the cleaning system according to the present invention rotates on the surface S1 of the cleaning material S while contacting the surface of the cleaning roller 111 and rotating. The cleaning roller 111 removes foreign matters such as dust (conductor or dielectric not shown) that move relative to the surface S1 of the material S to be cleaned by electrostatic force.

The cleaning roller 111 is capable of charging the surface with a charge that adsorbs foreign matter adhering on the surface S1 of the material to be cleaned S by electrostatic force. The charging property of the roller surface (outer peripheral surface) of the cleaning roller 111 is used. Thus, foreign matter is adsorbed. This cleaning roller 111 is rotatably held by an insulating member (not shown), and rotates while contacting the surface (outer peripheral surface) of the cleaning roller 111 on the side opposite to the material to be cleaned S. 121 and a transfer roller 131 are provided, and one cleaning unit U is configured. These

rollers

121 and 131 are also rotatably held by an insulating member (not shown).

The charge control roller 121 can stably charge the outer peripheral surface (outer layer portion) of the cleaning roller 111 with a charge for adsorbing foreign matter adhering on the surface S1 of the cleaning material S by electrostatic force. . Further, the transfer roller 131 can stably charge the outer peripheral surface (outer layer portion) of the transfer roller 131 with a charge for adsorbing foreign matter adhering to the surface of the cleaning roller 111 by electrostatic force.

The transfer roller 131 rotates together with the cleaning roller 111, and generates a potential difference between the

rollers

131 and 111 according to the difference in surface characteristics (for example, charging sequence) of the

rollers

131 and 111. As a result, contact peeling due to rotation of the cleaning roller 111 and the transfer roller 131 causes a potential difference in the transfer roller 131 according to a difference in surface characteristics (for example, charging sequence) from the cleaning roller 111, and the surface of the cleaning roller 111 is changed. Electric charge for adsorbing the adhering foreign matter by electrostatic force is charged.

Subsequently, the cleaning roller 111, the charge control roller 121, and the transfer roller 131 will be described.

(Cleaning roller 111)
The cleaning roller 111 includes a conductive metal core (core bar) 111a, a cylindrical inner layer portion 111b provided outside the metal core 111a, and a higher resistance than the inner layer portion 111b provided outside the inner layer portion 111b. And a thin cylindrical outer layer portion 111c (for example, a thickness of about 30 μm), which has a two-layer structure.

The material forming the outer layer portion 111c of the cleaning roller 111 has a charge for adsorbing foreign matter such as dust adhering to the surface S1 of the material to be cleaned S by electrostatic force as in the case of the cleaning roller 11 described above. Those that can be charged are selected.

The thickness of the outer layer portion 111c of the cleaning roller 111 is also preferably 2 to 500 μm (more preferably 5 to 50 μm) for the same reason as in the case of the cleaning roller 11 described above. Instead of the core metal 111a, a conductive carbon A core rod made of a material or a synthetic resin composite material can also be used.

The material used for the outer layer portion 111c of the cleaning roller 111 is the same as that of the cleaning roller 11 described above.

Further, the inner layer portion 11b of the cleaning roller 111 is the same as that of the cleaning roller 11 described above.

(Charging control roller 121)
The charge control roller 121 includes a conductive metal core (core bar) 121a, a cylindrical inner layer part 121b provided outside the metal core 121a, and an outer layer part 121c provided outside the inner layer part 121b. The volume resistivity of the outer layer portion 121c is set to be higher than that of the inner layer portion 121b. The cored bar 121a, the inner layer part 121b, and the outer layer part 121c of the charge control roller 121 can also be formed using, for example, a material that generates a potential difference depending on the difference in surface characteristics from the cleaning roller 11. Note that, as in the cleaning unit U ′ shown in FIG. 12B, the charge control roller 121 ′ may have a structure in which a cylindrical outer layer portion 121c ′ is directly provided outside the cored bar 121a ′.

A first external power supply 141 is connected to the cores 121a and 121a ′ of the

charge control rollers

121 and 121 ′, and the first external power supply 141 is connected to the cores 121a and 121a ′ of the

charge control rollers

121 and 121 ′. Thus, a voltage can be applied. Thereby, in order to adsorb the foreign matter adhering on the surface S1 of the material to be cleaned S by electrostatic force, the charge (sign of charge and magnitude of charge) charged to the cleaning roller 111 can be arbitrarily changed.

The charge control roller 121 can charge the cleaning roller 111 with a charge that adsorbs foreign matter adhering to the surface S1 of the material to be cleaned S by electrostatic force. In the case shown in FIG. The core metal 121a of the charge control roller 121 is set to a reference potential (for example, ground potential, that is, 0 V).

Similarly to the cleaning roller 11 described above, the cleaning roller 111 that rotates with the charge control roller 121 is charged by contact peeling with the charge control roller 121, and the cleaning roller 111 and the charge control roller 121 are separated from each other. Depending on the difference in surface properties between them, a potential difference is generated based on the charging sequence.

(Transfer roller 131)
The transfer roller 131 includes a conductive metal core (core bar) 131a, a cylindrical inner layer part 131b provided outside the metal core 131a, and an outer layer part 131c provided outside the inner layer part 131b. In addition, the roller surface can be charged with a charge that adsorbs the foreign matter adhering to the surface of the cleaning roller 111 by the electrostatic force by the electrostatic force. The outer layer portion 131c of the transfer roller 131 has a higher volume resistivity than the inner layer portion 131b. However, as shown in FIG. 12B, the transfer roller 131 ′ may also have a structure in which a cylindrical outer layer portion 131c ′ (elastic layer portion) is directly provided on the core bar 131a ′. Further, as a material of the outer layer portion 131c ′ of the transfer roller 131 ′, a potential difference generated according to a difference in surface characteristics between the cleaning roller 111 and the transfer roller 131 ′ due to contact peeling due to rotation with the cleaning roller 111 is stabilized. It is desirable to select one that is as large as possible without compromising the properties.

The transfer roller 131 has the same polarity as the charging voltage generated in the cleaning roller 111 by the accompanying rotation when the voltage applied by the first external power supply 141 installed on the core 121a of the charge control roller 121 is 0V, for example. In addition, the absolute value of the charged voltage generated in the transfer roller 131 is set to be larger than the absolute value of the charged voltage generated in the cleaning roller 111.

Therefore, when the foreign matter adsorbed by the electrostatic force on the cleaning roller 111 comes into contact with the transfer roller 131 by the rotation of the cleaning roller 111, a potential difference is generated between the transfer roller 131 and the cleaning roller 111 according to the difference in surface characteristics. Therefore, the foreign matter leaves the outer peripheral surface of the cleaning roller 111 and is transferred (moved) to the outer peripheral surface of the transfer roller 131.

As a result, the foreign matter on the outer peripheral surface of the cleaning roller 111 is continuously transferred to the transfer roller 131 side, and the cleaning roller 111 is in a state where the cleaning effect can be exhibited at any time. The adsorption operation can be continued. Therefore, maintenance work for periodically removing foreign matters on the outer peripheral surface of the cleaning roller 111 or replacing the cleaning roller 111 is not required, and the maintainability is improved.

In the above cleaning system, when the voltage applied by the first external power source 141 is opposite in polarity to the charged voltage of the transfer roller 131 and the absolute value of the charged voltage is large, the charging polarity of the transfer roller 131 is reversed. The suction force of the transfer roller 131 can be weakened. Therefore, the first external power supply 141 applies a voltage having a large absolute value with a reverse sign to the charge charged on the surface of the transfer roller 131 during the transfer operation by the transfer roller 131 except during cleaning by the cleaning roller 111. Application to 121 facilitates the removal of foreign matter adhering to the transfer roller 131.

Therefore, in the above unit, for example, when the potential difference generated by the rotation of the charging control roller 121 and the cleaning roller 111 is 300 V and the charging control roller 121 exhibits a positive charging property with respect to the cleaning roller 111, the charging control is performed. When the voltage applied by the first external power supply 141 installed on the roller 121 is 0V, the cleaning roller 111 becomes −300V. When the potential difference generated by the rotation of the cleaning roller 111 and the transfer roller 131 is 300V, and the cleaning roller 111 exhibits a positive charging property with respect to the transfer roller 131, the transfer roller 131 becomes −600V. In this case, the foreign matter having a positive chargeability with respect to the cleaning roller 111 is attracted to the cleaning roller 111 by electrostatic force and transferred from the cleaning roller 111 to the transfer roller 131.

On the other hand, if the voltage applied by the first external power supply 141 is changed from 0 V to +900 V, for example, the cleaning roller 111 becomes +600 V, the transfer roller 131 becomes +300 V, and the charging polarity of the transfer roller 131 changes from the minus side to the plus side. Is done. As a result, the transfer roller 131 loses the adsorbing force against the foreign matter showing the positive charging property that is attracted to the transfer roller 131 by the electrostatic force, and the foreign matter can be easily removed from the transfer roller 131.

Incidentally, as means for removing foreign matter from the transfer roller 131, it is desirable to employ, for example, wiping, brushing, scraping with a rubber blade, air blowing, or other appropriate means.

For example, like the cleaning unit U1 shown in FIG. 13, a cleaning brush 151 that rotates in the direction opposite to the rotation direction with respect to the transfer roller 131 and scrapes off the foreign matter adhering to the surface of the transfer roller 131 by electrostatic force is rotatably provided. A metal roller 152 made of, for example, a stainless alloy (SUS304) can be installed so as to rotate in a rotating direction with respect to the cleaning brush 151. The cleaning brush 151 has a hair 151b (brush portion) made of synthetic resin on a core metal 151a. A second external power source 153 is connected to the metal roller 152, and a potential difference is generated between the metal roller 152 and the transfer roller 131. That is, a potential having the same sign as the electric charge charged on the surface of the transfer roller 131 at the time of cleaning is applied to the metal roller 152 by the second external power source 153 so as to generate a potential difference with the transfer roller 131.

In the vicinity of the surface of the metal roller 152, a cleaning blade 146 whose tip scraping part comes into contact with the surface of the metal roller 152 is provided, and the foreign matter adhering to the surface of the metal roller 152 is scraped off by the cleaning blade 146. The cleaning blade 146 is formed of an elastic body made of a synthetic resin (for example, thermosetting urethane resin) and is held by an insulating holder (not shown). Note that the holder of the cleaning blade 146 may be held by an insulator.

Further, near the surface of the metal roller 152, there is provided a suction port 145 for air vacuum means capable of sucking foreign matter with negative pressure. Since the cleaning blade 146 is disposed in the vicinity of the suction port 145, the foreign matter scraped off by the cleaning blade 146 is sucked and removed through the suction port 145. Thereby, the foreign material adhering to the metal roller 152 can be efficiently removed. Here, any air vacuum means may be used as long as it can suck foreign matter with a negative pressure, and for example, a known air vacuum pump can be employed.

According to the above unit, the cleaning roller 111 comes into contact with the foreign matter adhering to the cleaning target material S to be cleaned, so that foreign matters such as dust are adsorbed on the surface (outer layer portion 111c) of the cleaning roller 111 and cleaned. It is removed from the surface S1 of the material S.

Then, when the foreign matter adsorbed by the electrostatic force on the surface of the cleaning roller 111 comes into contact with the surface of the transfer roller 131 by the rotation of the cleaning roller 111, a potential difference is generated between the transfer roller 131 and the surface of the cleaning roller 111. Therefore, the foreign matter leaves the cleaning roller 111 and is transferred (moved) to the surface of the transfer roller 131.

The foreign matter adhering to the surface of the transfer roller 131 is scraped off from the transfer roller 131 by the cleaning brush 151 and is adsorbed on the surface of the metal roller 152. The foreign matter adhering to the surface of the metal roller 152 is scraped off by the cleaning blade 146, and the foreign matter scraped off by the cleaning blade 146 is removed by suction through the suction port 145 of the air vacuum means. If it is not left on the surface, the transfer roller 131, the cleaning brush 151, and the metal roller 152 can continuously remove foreign substances adhering to the surface of the cleaning roller 111 over a long period of time. The periphery of the transfer roller 131 and the metal roller 152 is not contaminated by the scraped foreign matter.

Therefore, it is not necessary to perform maintenance work such as periodically removing foreign matters on the surfaces of the cleaning roller 111 and the transfer roller 131 and exchanging the cleaning rollers 111 and the transfer roller 131. Since there is almost no possibility of getting dirty, it is excellent in maintainability.

Here, the suction operation by the air vacuum means may be performed all the time, but it can be configured to be driven except during the cleaning by the cleaning roller 111. In particular, the first external power supply 141 applies a voltage having a large absolute value opposite to the charge charged on the surface of the transfer roller 131 during the transfer operation by the transfer roller 131 except when the cleaning roller 111 performs cleaning. With the configuration that can be applied to 121, such a voltage is applied to the charging control roller 121 to eliminate the foreign matter adsorbing force by the transfer roller 131, so that the foreign matter can be sucked and removed more efficiently. In this case, whether or not the cleaning by the cleaning roller 111 is being performed may be determined by detecting the movement of the cleaning material electrically or mechanically. It may be determined by detecting the vertical displacement of the core metal 111a. It is also possible to adopt a structure in which the cleaning blade 146 is supported so as to be able to advance and retract so that the scraping portion of the cleaning blade 146 contacts the surface of the metal roller 152 only when the air vacuum means is driven.

In any of the above cases, since the cleaning roller 111 has a potential difference of +300 V with respect to the transfer roller 131, the foreign matter showing positive chargeability with respect to the cleaning roller 111 is temporarily transferred to the transfer roller 131. Then, the toner image is not transferred again to the cleaning roller 111.

Further, the potential difference generated according to the difference in surface characteristics between the

rollers

111 and 121 is generated with reference to the charging control roller 121 (for example, ground voltage 0 V). The numerical value is shown stably.

As shown in FIG. 14, two cleaning units U1 and U2 are arranged in a series, and the signs of the cleaning rollers 111 and 111A of each unit are reversed, so that positively charged foreign matter adhering to the cleaning material S is negatively charged. The negatively charged foreign matter can be removed by the positively charged cleaning roller 111A by the cleaning roller 111. In this way, the range of foreign matters that can be removed from the material to be cleaned S by the cleaning units U1, U2 (cleaning rollers 111, 111A) can be widened. Also in this case, in each of the cleaning units U1 and U2, the charging control rollers 121 and 121A, the transfer rollers 131 and 131A, the second external power sources 153 and 153A, the suction ports 145 and 145A of the vacuum means, the cleaning blades 146 and 146A, the cleaning Brushes 151 and 151A and metal rollers 152 and 152A are provided.

As shown in FIG. 15, a guide roller 154 is provided across the material to be cleaned S, and the material to be cleaned S is supported from above and below at a position where the cleaning roller 111 and the guide roller 154 are in contact with each other, and is stably supported. It is also possible to remove foreign substances.

In this case, the guide roller 154 is provided with the charge control roller 121 ″ and the first external power source 141 ″, and the guide roller 154 is charged so that the potential difference with respect to the cleaning roller 111 becomes large, thereby acting on the material to be cleaned S. The electric field strength can be further increased and the cleaning property can be improved. In other words, the electric field strength is highest at the position where the cleaning material S contacts the cleaning roller 111 and the guide roller 154, so that the charging control roller 121 ″ is installed on the guide roller 154 in accordance with the applied electric field. The charged foreign matter on the material to be cleaned S is efficiently adsorbed to the cleaning roller 111 and removed.

Further, instead of the guide roller 154, as shown in FIG. 16, by using the cleaning roller 111B, the cleaning of the back surface of the material S to be cleaned can be performed simultaneously with the cleaning of the surface by the cleaning unit U3. Also in this case, the charging control rollers 121 and 121B, the transfer rollers 131 and 131B, the second external power sources 153 and 153B, the suction ports 145 and 145B of the vacuum means, the cleaning blades 146 and 146B, the cleaning brushes 151 and 151B, and the metal roller 152 , 152B are provided.

Of course, in the cases shown in FIGS. 15 and 16 as well, it is possible to arrange two in the same manner as in the case shown in FIG.

Subsequently, a test on the foreign matter removal performance of the cleaning roller 111 will be described.

(Method)
In the cleaning system shown in FIG. 17, the charging control roller 121, the cleaning roller 111, and the transfer roller 131 held by an insulating member (not shown) are brought into contact with each other and rotated together at a peripheral speed of 5 m / min. An arbitrary voltage (ground 0 V, first external power supply ± 900 V) was applied to the cored bar 121 a of the control roller 121 by the first external power supply 141. The first external power supply 141 is set to 0 V when the material to be cleaned passes, that is, at the time of cleaning. In any other case, the first external power supply 141 is an arbitrary voltage (first external power supply +900 V in the case of Table 14; The external power supply -900 V) was applied. A second external power supply 153 is connected to a metal roller 152 provided to the transfer roller 131 via a cleaning brush 151, and the second external power supply 153 always applies an absolute value of 300 V with the same sign as the transfer roller potential at the time of cleaning. did. The cleaning brush 151 is provided so as to rotate in a direction opposite to the rotation direction with respect to the transfer roller 131, and the metal roller 152 is installed so as to rotate in the rotation direction with respect to the cleaning brush 151.

The suction port 145 of the air vacuum means has a gap length of 2 mm with respect to the surface (outer peripheral surface) of the metal roller 152, and a cleaning blade 146 is installed at a position 5 mm behind the roller surface in the advancing direction of the roller immediately below the opening end of the suction port 145. did.

For this, a sample in which foreign matter (polystyrene resin or acrylic resin having an average diameter of 1 μm, 10 μm) is sprayed on the cleaning material S (PET film: 15 cm × 15 cm × 100 μm) is used to evaluate the foreign matter removal performance of the cleaning roller 111. did. The evaluation experiment was performed for 5 cools, with 50 films as 1 cool.

Further, the foreign matter adhering to the cleaning roller 111 after completion of cleaning and the foreign matter adhering to the transfer roller 131 were confirmed.

The surface potentials of the cleaning roller 11, the charging control roller 121 and the transfer roller 131 during cleaning were measured using surface potential meters 161, 162 and 163 (Model 341B manufactured by Trek).

(Description of Examples and Comparative Examples)
The following Tables 10 and 11 show the roller structures of Examples 23 to 28 and Comparative Examples 14 and 15 in which the foreign matter removal test 1 was performed, and the compositions of the inner and outer layers are shown in Table 3. The production methods of the rollers of Examples and Comparative Examples shown in Tables 10 and 11 are as follows.

An inner layer portion (thickness 6 mm / width (dimension in the extension direction of the core metal) 240 mm) was formed on a core metal (material: made of aluminum alloy, size: diameter φ28 mm × length 250 mm). For those having an outer layer portion, an outer layer portion (thickness 30 μm / width 240 mm) was further formed outside the inner layer portion. As a result, the elastic layer has an outer diameter of 40 mm and a width of 240 mm. However, for a roller having no inner layer portion (the transfer roller of Examples 25 and 28 corresponds), an outer layer portion (thickness 30 μm / width 240 mm) was directly formed on the same core metal as described above.

(Test results)
Table 12 shows the test results when the foreign material is an acrylic resin, and Table 13 shows the test result when the foreign material is a polystyrene resin. Here, in the table, ○ marks indicate three points in the range of 650μm × 500μm using a digital microscope (Digital microscope VHX-200 KEYENCE, lens magnification 450 times). A case where no foreign matter is confirmed is indicated by a circle, and a case where a foreign object is confirmed is indicated by a cross.

In Examples 23 to 28 in which the first external power source 141 is connected to the core metal 121a of the charging control roller 121 and the voltage applied by the first external power source 141 is controlled, no foreign matter is accumulated in any of the cools. No decrease in cleaning property with time was confirmed. On the other hand, in Comparative Examples 1 and 2 in which the charging control roller 121 is connected to the ground, foreign matter is accumulated on the transfer roller 131, and it has been confirmed that the cleaning property is deteriorated over time.

Therefore, the cleaning performance of the cleaning roller 111 and the transfer performance of the transfer roller 131 can be maintained by voltage control by the first external power source 141, and foreign matter is not accumulated, so that it adheres to the surfaces of the cleaning roller 111 and the transfer roller 131. There is no need to perform maintenance work such as periodically removing (cleaning) the foreign matter or periodically replacing the cleaning roller 111 or the transfer roller 131 to which the foreign matter is attached.

In addition, by applying a voltage from the first external power source 141, a voltage having a large absolute value is applied to the charging control roller 121 with a reverse sign to the charge charged on the surface of the transfer roller 131 during cleaning. It has also been confirmed that the foreign matter can be easily removed from the transfer roller 131 by setting the charging property of the reverse polarity to 131 and weakening the attracting force of the foreign matter attracted to the transfer roller 131.

As shown in FIG. 18, the cleaning system 171 includes a cleaning unit 172 that removes foreign matter (conductor or dielectric) such as dust adhering to the surface S1 of the material to be cleaned S by using electrostatic force, and the cleaning unit. The apparatus includes a carry-in unit 173 that conveys the cleaning material S toward the 172, and a carry-out unit 174 that carries out the cleaning material S after cleaning from the cleaning unit 171.

The carry-in unit 173 is configured such that a conveyance belt 173C is wound around a pair of rollers 173A and 173B, and the material to be cleaned S on the conveyance belt 173C is conveyed toward the cleaning unit 172.

The carry-out unit 174 is configured so that the conveyance belt 174C is wound around the pair of rollers 174A and 174B, and the cleaning material S discharged from the cleaning unit 172 onto the conveyance belt 174C is conveyed in a direction away from the cleaning unit 172. It has become.

The cleaning unit 172 includes a pair of cleaning rollers 111 that rotate while bringing the surface into contact with the surface S1 (upper surface) of the material to be cleaned S. The surfaces of the charge control roller 121 and the transfer roller 131 with respect to each cleaning roller 111. Rotate while in contact. In addition, a pair of cleaning rollers 111 is also disposed on the back surface (lower surface) of the cleaning material S corresponding to the upper cleaning roller 111, and the cleaning material S is sandwiched between the cleaning roller 111 and the cleaning material 111. The cleaning material S is moved to the carry-out portion 174 side. The cleaning roller 111 is also provided with a transfer roller 131 corresponding to the charging control roller 121. The rotational force of the driving roller 176 is transmitted to the shaft portion of the cleaning roller 111 via the driving belt 175 so that the cleaning roller 111 is rotationally driven.

A first external power source (high voltage power source) 141 is connected to the core of each charging control roller 121, and a metal roller 152 is provided on each transfer roller 131 via a cleaning brush 151. On the other hand, a suction port 145 and a cleaning blade 146 of an air vacuum pump 178 (air vacuum means) are provided. Each suction port 145 is connected to an air vacuum pump 178 via a dust collector (filter) 177.

In the embodiment, the cleaning brush 151 is rotatably provided to the transfer roller 131, the metal roller 152 is installed on the cleaning brush 151, and the cleaning blade 146 and the air vacuum means are sucked in the vicinity of the surface of the metal roller 152. Although the opening 145 is provided, the present invention is not limited to such a structure. The cleaning brush and the metal roller are omitted, and the cleaning blade 146 and the air vacuum means are sucked in the vicinity of the surface of the transfer roller. A structure in which the mouth 145 is provided may be employed.

In the above embodiment, the charging control roller 121 is provided for the cleaning roller 111, but it can also be provided for the transfer roller 131 as shown in FIG.
Next, a test on the foreign matter removal performance of the cleaning roller 111 will be described.

(Method)
In the cleaning system shown in FIG. 19, the cleaning roller 111, the charging control roller 121, and the transfer roller 131 held by an insulating member (not shown) are brought into contact with each other and rotated together at a peripheral speed of 5 m / min. An arbitrary voltage (ground 0 V) was applied to the metal core 121a of the charge control roller 121 by the first external power supply 141. A second external power source 153 is connected to a metal roller 152 provided to the transfer roller 131 via a cleaning brush 151. The second external power source 153 has an absolute value of 1 kV having the same sign as the transfer roller potential during cleaning at the time of cleaning. In other cases, an absolute value of 1 kV was given by the opposite sign to the transfer roller potential at the time of cleaning. The cleaning brush 151 is provided so as to rotate in a direction opposite to the rotation direction with respect to the transfer roller 131, and the metal roller 152 is installed so as to rotate in the rotation direction with respect to the cleaning brush 151.

For this, a sample in which foreign matter (polystyrene resin or acrylic resin having an average diameter of 1 μm, 10 μm) is sprayed on the material to be cleaned S (glass epoxy substrate with copper foil: 12 cm × 12 cm × 2 mm) is used. The foreign substance removal performance was evaluated. Here, in the table, ○ marks indicate three points in the range of 650 μm × 500 μm using a digital microscope (digital microscope VHX-200 KEYENCE, lens magnification: 450 times). A case where no foreign matter is confirmed is indicated by a circle, and a case where a foreign object is confirmed is indicated by a cross. The evaluation experiment was performed continuously for 5 cools with 50 glass epoxy substrates as 1 cool.

In addition, the surface potential of the cleaning roller 111 during cleaning was measured using a surface potential meter (Mode 1 341B manufactured by Trek). Furthermore, the copper foil surface of the material to be cleaned was connected to the ground, and the value of current flowing on the copper foil surface during cleaning was measured.

Table 14 shows the roller structures of Examples 29 to 32 and Comparative Examples 16 to 19, and Table 3 shows the compositions of the inner and outer layers. In Comparative Examples 16 to 19, as shown in FIG. 13, the charging control roller 121 is arranged so as to rotate while contacting the surface of the cleaning roller 111.

(Description of Examples and Comparative Examples)
An inner layer portion (thickness 6 mm / width (dimension in the extension direction of the core metal) 240 mm) was formed on a metal core (material: aluminum alloy size: diameter φ28 mm × length 250 mm). In the case of the outer layer portion, an outer layer portion (thickness 30 μm / width 240 mm) was further formed outside the inner layer portion, so that the elastic layer had an outer diameter of φ40 mm and a width of 240 mm. For the rollers that do not (charge control rollers correspond), the outer layer (thickness 30 μm / width 240 mm) was formed directly on the same cored bar as described above.

From the results shown in Table 14, in Examples 29 to 32 in which the charge control roller 121 is provided on the transfer roller 131, the foreign matter is removed in any sample, the cleaning property does not deteriorate with the passage of time, and the length is long. It can be seen that stable cleaning performance can be obtained over a period of time. On the other hand, in Comparative Examples 16 to 19 in which the charge control roller 121 is provided for the cleaning roller 111, it was confirmed that the cleaning property deteriorated with time.

Further, by providing the charging control roller 121 with respect to the transfer roller 131, the current generated from the second external power source 153 is prevented from flowing into the cleaning roller 111, and the current flowing through the cleaning material S is reduced. It has also been confirmed that electrical damage to the cleaning material S can be prevented even if the cleaning material S is a conductive material or the like. In other words, in a system in which the charging control roller 121 that rotates while contacting the surface of the cleaning roller 111 is in contact with the cleaning roller 111, a current generated from the second external power source 153 flows into the cleaning roller 111, When S is a conductive material, the cleaning material S may be damaged. However, by introducing the charge control roller 121 not onto the cleaning roller 111 but onto the transfer roller 131, the cleaning roller 111 can be replaced with the cleaning roller 111. It is possible to prevent the current generated from the external power source 153 from flowing in, and to prevent electrical damage to the cleaning material S.

FIG. 20 shows an example of the overall configuration of the cleaning system having the cleaning unit described above.

(Second specific embodiment)
As shown in FIG. 21 (a), in the cleaning unit U used in the cleaning system, the surface (outer peripheral surface) of the cleaning roller 211 is moved relative to the surface S1 of the material to be cleaned S while being rotated, Foreign matter such as dust (conductor or dielectric, not shown) adhering to the surface S1 of the material to be cleaned S is removed by the cleaning roller 211 using electrostatic force.

This cleaning roller 211 is capable of charging the surface with a charge for adsorbing foreign matter adhering to the surface S1 of the material to be cleaned S by electrostatic force by contact peeling with the material to be cleaned S. A core bar (core bar) 211a, a cylindrical inner layer portion 211b provided on the outer side of the core bar 211a, and a thin cylindrical shape made of a material having higher resistance than the inner layer portion 211b provided on the outer side of the inner layer portion 211b. The outer layer portion 211c (for example, a thickness of about 30 μm) is provided and has a two-layer structure. The first external power supply 21 is connected to the cored bar 211 a of the cleaning roller 211.

A transfer roller 231 that rotates while being in contact with the surface of the cleaning roller 211 is provided for the cleaning roller 211 that adsorbs foreign matter by electrostatic force using the charging property of the roller surface. The transfer roller 231 can charge the surface with a charge for adsorbing foreign matter adhering to the surface of the cleaning roller 211 by electrostatic force. Foreign matter adhering to the cleaning roller 211 due to electrostatic force is transferred (moved) to the transfer roller 231 side. At the same time, by changing the voltage applied by the first external power source 221 connected to the cleaning roller 211, the voltage applied to the transfer roller 231 for adsorbing the foreign matter by electrostatic force can be arbitrarily changed. It has become.

The transfer roller 231 includes a conductive metal core (core bar) 231a, a cylindrical inner layer portion 231b provided outside the metal core 231a, and an outer layer portion 231c provided outside the inner layer portion 231b. The outer layer portion 231c has a higher volume resistivity than the inner layer portion 231b.

A cleaning brush 243 that rotates in a direction opposite to the rotation direction with respect to the transfer roller 231 and scrapes foreign matter adhering to the surface of the transfer roller 31 by electrostatic force is rotatably provided. For example, a metal roller 244 made of stainless alloy (SUS304) is installed so as to rotate. This cleaning brush 243 has a hair portion 243b (brush portion) made of synthetic resin on a metal core 243a. A second external power source 245 is connected to the metal roller 244, and has a mechanism for generating a potential difference with the transfer roller 231. That is, the second external power source 245 applies a potential having the same sign as the electric charge charged on the surface of the transfer roller 231 during cleaning to the metal roller 244.

In the vicinity of the surface of the metal roller 244, a cleaning blade 241 whose tip scraping part comes into contact with the surface of the metal roller 244 is provided, and the foreign matter adhering to the surface of the metal roller 244 is scraped off by the cleaning blade 241. The cleaning blade 241 is formed of an elastic body made of a synthetic resin (for example, thermosetting urethane resin) and is held by an insulating holder (not shown). Note that the holder of the cleaning blade 241 may be held by an insulator.

Further, the suction port 242 of the air vacuum means capable of sucking foreign matter by negative pressure near the surface of the metal roller 244 and near the contact portion between the roller surface of the transfer roller 231 and the scraping portion of the cleaning blade 241. Is provided. Since the cleaning blade 241 is disposed in the vicinity of the suction port 242, the foreign matter scraped off by the cleaning blade 241 is sucked and removed through the suction port 242. Thereby, the foreign material adhering to the metal roller 244 can be efficiently removed. Here, any air vacuum means may be used as long as it can suck foreign matter with a negative pressure, and for example, a known air vacuum pump can be employed.

As described above, when the foreign matter is sucked and removed from the metal roller 244, the tip scraping portion of the cleaning blade 241 contacts the metal roller 244 in the vicinity of the suction port 242 of the air vacuum means to scrape the foreign matter. As a result, the foreign matter adhering to the metal roller 44 is efficiently removed and the surroundings are not soiled.

The cleaning roller 211 and the transfer roller 231 are held by an insulating material (not shown), and the transfer roller 231 rotates together with the cleaning roller 211, and each roller is between the

rollers

231 and 211. A potential difference is generated according to the difference in the surface characteristics of 231 and 211. As a result, contact peeling due to the rotation of the cleaning roller 211 and the transfer roller 231 causes a potential difference on the roll surface of the transfer roller 231 according to a difference in surface characteristics (for example, charging order) with the cleaning roller 211, A charge for adsorbing foreign matter adhering to the surface by electrostatic force is charged.

A voltage can be applied to the metal core 211a of the cleaning roller 211 by the first external power supply 221. For example, the voltage applied by the first external power supply 221 connected to the metal core 211a of the cleaning roller 211 is 0V. In this case, when a voltage having the same polarity as that of the charged voltage generated in the transfer roller 231 due to the follow rotation is applied to the first external power source 221, the cleaning roller 211 adsorbs foreign matter from the material to be cleaned S. The transfer roller 231 can transfer the foreign matter attached to the cleaning roller 211.

The foreign matter adsorbed on the transfer roller 231 under the above condition has a polarity opposite to the charged voltage generated in the transfer roller 231 due to the rotation with respect to the core metal 211a of the cleaning roller 211 when the applied voltage of the above condition is 0V. By applying a voltage having an absolute value larger than the absolute value of the charged voltage from the first external power source 221, the transfer roller 231 loses an adsorbing force (electrostatic force) for adsorbing foreign matter. Accordingly, the foreign matter is scraped off by the cleaning brush 243 and moves to the surface of the metal roller 244. The foreign matter that has moved to the surface of the metal roller 244 is scraped off by the cleaning blade 241 and is removed by suction through the suction port 242 of the air vacuum means.

The transfer roller 231 used here has the same structure as that of the cleaning roller 211. However, like the unit U1 ′ shown in FIG. 21B, the transfer roller 231 ′ has a core metal 231a ′ (except for the inner layer portion). A structure in which a cylindrical outer layer portion 231c ′ is directly provided outside the core rod) may be employed. The material of the outer layer portion is preferably selected so that the potential difference with respect to the charged voltage of the cleaning roller 211 is as large as possible within a range that does not impair the stable attracting force due to electrostatic force.

The thickness of the outer layer portion 211c of the cleaning roller 211 is preferably 2 to 500 μm (more preferably 5 to 50 μm), like the

cleaning rollers

11 and 111 described above. In place of the cored bar 211a, a cored bar made of a conductive carbon material, synthetic resin composite, or the like can be used.

The material used for the outer layer portion 211c and the material used for the inner layer portion 211b are the same as those of the cleaning

rollers

11 and 111 described above.

The transfer roller 231 includes a conductive metal core (core bar) 231a, a cylindrical inner layer portion 231b provided outside the metal core 231a, and an outer layer portion 231c provided outside the inner layer portion 231b. The roller surface can be charged with electric charge for adsorbing foreign matter adhering to the surface of the cleaning roller 211 by electrostatic force. The outer layer portion 231c of the transfer roller 231 has a higher volume resistivity than the inner layer portion 231b. It has the same polarity as the voltage applied to the first external power supply 221 and is set so that the absolute value becomes large. At the same time, the transfer roller 231 arbitrarily changes the charged voltage for adsorbing foreign matter adhering to the surface of the cleaning roller 211 by electrostatic force by the first external power source 221 connected to the core metal 211a of the cleaning roller 211. it can.

As a result, the foreign matter adhering to the cleaning roller 211 due to electrostatic force is sequentially transferred (moved) to the transfer roller 231 side as it rotates. As a result, no foreign matter remains on the surface of the cleaning roller 211, and no foreign matter is returned to the surface S1 of the material to be cleaned S. Therefore, the cleaning roller 211 continues the foreign matter adsorption operation for a long period of time. Can be done.

According to the above unit, the cleaning roller 211 comes into contact with the foreign matter adhering to the cleaning target material S to be cleaned, so that foreign matters such as dust are adsorbed to the surface (outer layer portion 211c) of the cleaning roller 211 and cleaned. It is removed from the surface S1 of the material S.

Then, when foreign matter adsorbed by the electrostatic force on the surface of the cleaning roller 211 comes into contact with the surface of the transfer roller 231 by the rotation of the cleaning roller 211, a potential difference is generated between the transfer roller 231 and the surface of the cleaning roller 211. Therefore, the foreign matter leaves the cleaning roller 211 and is transferred (moved) to the surface of the transfer roller 231.

The foreign matter adhering to the surface of the transfer roller 231 is scraped off from the transfer roller 231 by the cleaning brush 243 and is adsorbed on the surface of the metal roller 244. The foreign matter scraped off by the cleaning blade 241 adhered to the surface of the metal roller 244 is sucked and removed through the suction port 242 of the air vacuum means.

As a result, no foreign matter remains on the surface of the cleaning roller 211, and no foreign matter is returned to the surface S1 of the cleaning material S. Therefore, the cleaning roller 211 continues the suction operation of the foreign matter for a long period of time. It can be carried out. Further, the foreign matter scraped from the metal roller 211 by the cleaning blade 241 is immediately sucked and removed through the suction port 242 of the air vacuum means, so that the periphery of the metal roller 211 is not soiled by the scraped foreign matter. .

Accordingly, the maintenance work for periodically removing the foreign matter on the surface of the cleaning roller 211 or the transfer roller 231 or replacing the cleaning roller 211 or the transfer roller 231 is not necessary, and the periphery of the transfer roller 231 is caused by the foreign matter. Since there is almost no possibility of getting dirty, maintenance is excellent.

Here, the suction operation by the air vacuum means may be always performed, but the first external power source 221 is charged on the surface of the transfer roller 231 during the transfer operation by the transfer roller 231 except for the cleaning by the cleaning roller 211. The voltage of the absolute value larger than the absolute value of the charging voltage of the transfer roller 231 is applied to the cleaning roller 211, and the air vacuum means is driven except when cleaning is performed by the cleaning roller 211. It can also be configured. Here, “during cleaning” refers to the time when the cleaning roller 211 moves relative to the surface of the material to be cleaned while rotating. During cleaning by the cleaning roller 211, the movement of the material to be cleaned may be detected electrically or mechanically, and the passage of the material to be cleaned S may be determined by, for example, the vertical displacement of the metal core 211a of the cleaning roller 211. You may make it detect and determine. It is also possible to adopt a structure in which the cleaning blade 241 is supported so as to be able to advance and retract so that the tip scraping portion of the cleaning blade 241 contacts the surface of the metal roller 211 only when the air vacuum means is driven.

Subsequently, an example of the relationship between the cleaning roller 211 and the transfer roller 231 in the cleaning unit U1 will be described.

First, in the above cleaning unit, when the potential difference generated by the rotation of the transfer roller 231 and the cleaning roller 211 is 300 V, and the cleaning roller 211 exhibits a positive charging property with respect to the transfer roller 231 (the charging sequence becomes a positive side). 22), when the voltage applied by the external power source 221 connected to the cleaning roller 211 is 0V, the transfer roller 231 is −300V and the cleaning roller 211 is 0V, as shown in FIG.

As shown in FIG. 22B, if the voltage applied by the external power source 221 is −300 V, the transfer roller 231 is −600 V, the cleaning roller 211 is −300 V, and the positive chargeable foreign matter is removed from the cleaning roller. After being attracted to 211, it is transferred to and attracted to the transfer roller 231.

Thereafter, as shown in FIG. 22C, if the voltage applied by the external power source 221 is +600 V, the transfer roller 231 is +300 V, the cleaning roller 211 is +600 V, and a foreign material having a positive charging property is charged to the positive side. Attempts to leave the transfer roller 231. In this state, the foreign matter is scraped off from the transfer roller 231 by the cleaning brush 243 and moves onto the surface of the metal roller 244. The foreign matter that has moved to the surface of the metal roller 244 is scraped by the tip scraping portion of the cleaning blade 241 in the vicinity of the suction port 242 of the air vacuum means, and is sucked through the suction port 242 of the air vacuum means, and the roller surface of the metal roller 244 Removed from above.

In addition, when the potential difference generated by the rotation of the transfer roller 231 and the cleaning roller 211 is 300 V and the cleaning roller 11 exhibits a negative chargeability with respect to the transfer roller 231 (when the charge sequence is negative), As shown in FIG. 22D, when the voltage applied by the external power source 221 connected to the cleaning roller 211 is 0V, the transfer roller 231 is + 300V and the cleaning roller 211 is 0V.

As shown in FIG. 22E, if the voltage applied by the external power source 221 is +300 V, the transfer roller 231 is +600 V, the cleaning roller 211 is +300 V, and negatively charged foreign matter is attracted to the cleaning roller 211. Then, the toner is transferred and attracted to the transfer roller 231.

Thereafter, as shown in FIG. 22 (f), if the voltage applied by the external power source 221 is -600V, the transfer roller 231 is -300V, the cleaning roller 211 is -600V, and foreign matter having negative chargeability is negative. Attempts to leave the transfer roller 231 charged to the side. In this state, the foreign matter is scraped off by the cleaning brush 243 and moves onto the surface of the metal roller 244. The foreign matter that has moved on the surface of the metal roller 244 is scraped by the tip scraping portion of the cleaning blade 241 near the suction port 242 of the air vacuum means, and is sucked through the suction port 242 of the air vacuum means. Removed from.

Since the potential difference generated according to the difference in surface characteristics between the

rollers

211 and 231 is generated with reference to the charged voltage of the cleaning roller 211, a constant numerical value is stably displayed at a constant peripheral speed.

22A to 22C, since the cleaning roller 211 has a potential of +300 V on the plus side with respect to the transfer roller 231, the plus side once transferred to the transfer roller 231 is used. The foreign matter showing the charging property is not retransferred to the cleaning roller 211. Similarly, in the case of FIGS. 22D to 22F, the cleaning roller 211 has a potential of −300 V on the minus side with respect to the transfer roller 231, and thus the minus that has been transferred to the transfer roller 231 once. The foreign matter showing the charging property on the side is not retransferred to the cleaning roller 211. In these cases, the reference is the voltage applied by the first external power source 221 connected to the cored bar 211a of the cleaning roller 211.

Subsequently, test results regarding the performance of the cleaning roller 211 will be described.

(Method)
In the cleaning system shown in FIG. 23, the transfer roller 231 and the cleaning roller 211 held by an insulating member (not shown) are brought into contact with each other and rotated together at a peripheral speed of 5 m / min, so that the cleaning roller 211 (core metal 211a) is rotated. ) Was given an arbitrary voltage (± 300 V, ± 600 V) by the first external power source 221.

The first external power source 221 applies any of ± 300 V when the material to be cleaned S passes (that is, during cleaning). In other cases, the first external power source 221 has ± 600 V with a polarity opposite to the previously applied potential. The voltage was set to be applied. The second external power supply 245 always applied the same value as the voltage applied when the first external power supply 221 passes the cleaning material.

The cleaning brush 243 was installed so as to rotate in the opposite direction with respect to the transfer roller 231 and the metal roller 244 so as to rotate in the accompanying direction with respect to the cleaning brush 243. The suction port 242 of the air vacuum means has a gap length of 2 mm with the roller surface of the metal roller 244, and a cleaning blade 241 is installed at a position 5 mm behind the metal roller 244 in the advancing direction from the roller surface immediately below the opening end of the suction port 242. .

For this, using a sample in which foreign matter (polystyrene resin or acrylic resin having an average diameter of 1 μm, 10 μm) is sprayed on the material to be cleaned S (PET film: 15 cm × 15 cm × 100 μm), the foreign matter removal performance of the cleaning roller 211 is evaluated did. In addition, the evaluation experiment was performed 5 times continuously with 10 films as 1 cool.

In addition, the foreign matter adhering to the cleaning roller 211 after completion of cleaning and the foreign matter adhering to the transfer roller 231 were confirmed.

The surface potentials of the cleaning roller 211 and the transfer roller 231 during cleaning were measured using surface potential meters 261 and 262 (Model 341B manufactured by Trek).

(Description of Examples and Comparative Examples)
The following Tables 15 and 16 show the roller structures of Examples 33 to 48 and Comparative Examples 20 and 21 in which the foreign matter removal test 1 was performed. The compositions of the inner and outer layers are shown in Table 3 above. The production methods of the rollers of Examples 33 to 48 and Comparative Examples 20 and 21 shown in Tables 15 and 16 are as follows.

An inner layer portion (thickness 6 mm / width (dimension in the extension direction of the core metal) 240 mm) was formed on a metal core (material: made of aluminum alloy, size: diameter φ28 mm × length 250 mm). For those having an outer layer portion, an outer layer portion (thickness 30 μm / width 240 mm) was further formed outside the inner layer portion. As a result, the elastic layer has an outer diameter of 40 mm and a width of 240 mm. However, for the roller having no inner layer portion (corresponding to the transfer roller of Examples 33 and 41), the outer layer portion (thickness 30 μm / width 240 mm) was directly formed on the same cored bar as described above.

(Test results)
Table 17 shows the case where the foreign material is an acrylic resin, and Table 18 shows the case where the foreign material is a polystyrene resin. Here, in the table, ○ marks indicate three points in the range of 650μm × 500μm using a digital microscope (Digital microscope VHX-200 KEYENCE, lens magnification 450 times). A case where no foreign matter is confirmed is indicated by a circle, and a case where a foreign object is confirmed is indicated by a cross.

From Tables 17 and 18, in Examples 33 to 48 in which the first external power source 221 was connected to the cleaning roller 211 and a voltage was applied, the accumulation of foreign matter on the transfer roller was not confirmed even after continuous use. There was no decline in sex.

On the other hand, in Comparative Examples 20 and 21 in which a transfer roller that cannot obtain the effects of the present invention was used as the cleaning roller, continuous cleaning properties could not be obtained.

Further, as shown in FIG. 24, two cleaning units U1 and U2 are arranged, and the sign of the electric charge charged to the cleaning rollers 211 and 211A of each unit U1 and U2 is reversed, so that the material to be cleaned S is provided. It is possible to remove adhering foreign matter having a positive charging property with the cleaning roller 211 charged to the negative side, and removing foreign matter showing negative charging property with the cleaning roller 211A charged to the positive side. Reference numerals 221 and 221A denote first external power supplies, and reference numerals 231 and 231A denote transfer rollers.

Further, as shown in FIG. 25, a guide roller 251B is provided on the opposite side of the cleaning roller 211 with the material to be cleaned S interposed therebetween, a transfer roller 231B is provided for the guide roller 251B, and the cleaning roller 211 is provided by the guide roller 251B. Further, the electric field strength acting on the cleaning material S sandwiched between the guide roller 251B and the guide roller 251B can be further increased, and the cleaning performance can be improved.

In this case, by using a cleaning roller instead of the guide roller 251B, it is possible to simultaneously clean the back surface of the material to be cleaned S. Further, as in the case shown in FIG. 24, two units can be arranged.

As shown in FIG. 26, the cleaning system 271 includes a cleaning unit 272 that removes foreign matter (conductor or dielectric) such as dust that adheres to the surface S1 of the material S to be cleaned using electrostatic force, and the cleaning unit. 272 includes a carry-in unit 273 that conveys the cleaning material S toward the 272, and a carry-out unit 274 that carries out the cleaned material S after cleaning from the cleaning unit 272.

The carrying-in unit 273 is configured such that a conveyance belt 273C is wound around a pair of rollers 273A and 273B, and the material to be cleaned S on the conveyance belt 273C is conveyed toward the cleaning unit 272.

The carry-out unit 274 is configured such that the conveyance belt 274C is wound around the pair of rollers 274A and 274B, and the cleaning material S discharged from the cleaning unit 272 onto the conveyance belt 274C is conveyed in a direction away from the cleaning unit 272. It has become.

The cleaning unit 272 includes a pair of cleaning rollers 211 that rotate while the surface is in contact with the surface S1 (upper surface) of the material S to be cleaned. The cleaning unit 272 rotates while the surface of the transfer roller 231 is in contact with each cleaning roller 211. It is supposed to be. In addition, a pair of cleaning rollers 211 is also disposed on the back surface (lower surface) of the material to be cleaned S corresponding to the upper cleaning roller 211, and the material to be cleaned S is sandwiched between the cleaning roller 211. The cleaning material S is moved to the carry-out portion 274 side. The cleaning roller 211 is also provided with a transfer roller 231 corresponding thereto. The rotational force of the driving roller 276 is transmitted to the shaft portion of the cleaning roller 211 via the driving belt 275 so that the cleaning roller 211 is driven to rotate.

Further, a first external power source (high voltage power source) 221 is connected to the core of each cleaning roller 211, and each transfer roller 231 is provided with a metal roller 244 via a cleaning brush 243. The second external power source 245 is connected. Further, a suction port 242 of an air vacuum pump 278 (air vacuum means) and a cleaning blade 241 are provided for the metal roller 244. Each suction port 242 is connected to an air vacuum pump 278 via a dust collector (filter) 277.

Claims

The cleaning system includes a cleaning roller that moves while rotating while contacting the surface of the material to be cleaned, and removes foreign matters such as dust adhering to the surface of the material to be cleaned using electrostatic force by the cleaning roller. And
The cleaning roller is capable of charging the outer peripheral surface with a charge that adsorbs foreign matter adhering to the surface of the material to be cleaned by electrostatic force.
A charging control roller that rotates while contacting the outer peripheral surface of the cleaning roller is provided for the cleaning roller,
The cleaning system, wherein the charge control roller is capable of charging the cleaning roller with an electric charge for adsorbing foreign matter adhering to the surface of the material to be cleaned by electrostatic force.
The charge control roller rotates while contacting the surface of the cleaning roller, thereby generating a potential difference with the cleaning roller according to the difference in surface characteristics between the charge control roller and the cleaning roller. The cleaning system according to claim 1, wherein:
A transfer roller that rotates while contacting the outer peripheral surface of the cleaning roller is provided for the cleaning roller,
This transfer roller includes a conductive core rod and a cylindrical elastic layer portion provided outside the core rod,
The elastic layer portion of the transfer roller has a volume resistivity higher than that of the core rod, and is formed of a material capable of charging an electric charge that adsorbs foreign matter adhering to the outer peripheral surface of the cleaning roller to the surface by electrostatic force. The cleaning system according to claim 1 or 2, wherein
A guide roller is disposed on the opposite side of the cleaning roller across the material to be cleaned,
4. The guide roller according to claim 1, wherein the guide roller enhances an electric field strength for adsorbing foreign matter adhering to the surface of the material to be cleaned by electrostatic force. The cleaning system described in.
The cleaning roller includes a conductive core rod, a cylindrical inner layer portion provided outside the core rod, and an outer layer portion provided outside the inner layer portion,
The cleaning system according to any one of claims 1 to 4, wherein the outer layer portion has a hardness (JIS-A) of 50 ° or more and has a higher volume resistivity than the inner layer portion.
The cleaning roller is formed of an elastic material in which the inner layer portion has conductivity,
6. The cleaning system according to claim 1, wherein the outer layer portion is formed of acrylic mixed urethane or fluorine mixed urethane.
A transfer roller that rotates while contacting the surface of the cleaning roller is provided for the cleaning roller,
The charge control roller has a first external power supply connected to a cored bar, and can change the charge for adsorbing foreign matter adhering on the surface of the cleaning material by electrostatic force to the cleaning roller. ,
The transfer roller is formed of a material capable of charging the surface with a charge that adsorbs foreign matter adhering to the surface of the cleaning roller by electrostatic force, and a first external power source connected to the core metal of the charge control roller 3. The cleaning system according to claim 1, wherein the charge for adsorbing the foreign matter by electrostatic force can be changed by the above.
A cleaning system that includes a cleaning roller that moves while rotating while being in contact with the surface of the material to be cleaned, and that removes foreign matters such as dust adhering to the surface of the material to be cleaned using electrostatic force by the cleaning roller. There,
The cleaning roller is connected to a first external power source and can charge the surface with a charge for adsorbing foreign matter adhering to the surface of the material to be cleaned by electrostatic force.
A transfer roller that rotates while contacting the surface of the cleaning roller is provided for the cleaning roller,
The transfer roller can charge the surface with a charge for adsorbing foreign matter adhering to the surface of the cleaning roller by electrostatic force, and can change the voltage applied by a first external power source connected to the cleaning roller. By doing so, a charging voltage for adsorbing the foreign matter by electrostatic force of the transfer roller can be changed.
The transfer roller rotates while contacting the surface of the cleaning roller, thereby generating a potential difference between the transfer roller and the cleaning roller according to the difference in surface characteristics between the transfer roller and the cleaning roller. The cleaning system according to claim 8.
A cleaning brush that rotates in a direction opposite to the rotation direction is provided for the transfer roller, and a metal roller is provided to rotate in the rotation direction with respect to the cleaning brush. Is connected, and is configured to generate a potential difference with the transfer roller. In the vicinity of the surface of the metal roller, the tip scraping part scrapes off foreign matter adhering to the surface of the metal roller. The cleaning system according to claim 7 or 9, wherein a blade is arranged.
The first external power supply supplies a voltage having a large absolute value to the charging control roller, which is opposite in sign to the charge charged on the surface of the transfer roller during the transfer operation by the transfer roller, except during cleaning by the cleaning roller. Is configured to apply,
The second external power source is configured to apply a potential having the same sign as the charge charged on the surface of the transfer roller to the metal roller during cleaning so as to generate a potential difference with the transfer roller. The cleaning system according to claim 10.
12. The cleaning system according to claim 10, wherein a suction port of air vacuum means capable of sucking foreign matter by negative pressure is provided near the surface of the metal roller.
A cleaning brush that rotates in a direction opposite to the rotation direction is provided for the transfer roller, and a metal roller is provided to rotate in the rotation direction with respect to the cleaning brush. Are configured to generate a potential difference with the transfer roller,
The cleaning system according to claim 8 or 9, wherein a cleaning blade is disposed near the surface of the metal roller to scrape foreign matter adhering to the surface of the metal roller at a tip scraping portion.
14. The cleaning system according to claim 13, wherein a suction port of air vacuum means capable of sucking foreign matter by negative pressure is disposed in the vicinity of a cleaning blade installed on the surface of the transfer roller.
A guide roller is disposed on the opposite side of the cleaning roller across the material to be cleaned,
15. The guide roller according to any one of claims 7 to 14, wherein the cleaning roller enhances an electric field strength for adsorbing foreign matter adhering to the surface of the material to be cleaned by electrostatic force. The cleaning system described in.
A cleaning system comprising a cleaning roller that moves while rotating in contact with the surface of the material to be cleaned, and that removes foreign matters such as dust adhering to the surface of the material to be cleaned using electrostatic force by the cleaning roller. There,
The cleaning roller is capable of charging the surface with a charge that adsorbs foreign matter adhering to the surface of the material to be cleaned by electrostatic force,
A transfer roller that rotates while contacting the surface of the cleaning roller with respect to the cleaning roller;
The transfer roller is formed of a material capable of charging the surface with a charge that adsorbs foreign matter adhering to the surface of the cleaning roller by electrostatic force, and is charged while rotating while contacting the surface of the transfer roller with respect to the transfer roller A roller is provided,
The charging control roller has a first external power source connected to a cored bar, and charges the foreign material adhering on the surface of the material to be cleaned by electrostatic force to the cleaning roller and the transfer roller. A cleaning system characterized in that it can be changed.