JP2011147884A - Cleaning material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning material having high capability of removing fine foreign matter attached to an object to be cleaned such as an electronic part or the like, easy to be peeled because of decreased residue of a glue, and convenient to be used in the process of producing an electronic part or the like. <P>SOLUTION: The cleaning material includes an urethane layer, wherein the surface of the urethane layer has surface roughness Ra of not less than 0.005 μm and not more than 0.1 μm on the surface and foreign matter adhering to an object to be cleaned is removed by bringing the object to be cleaned into plane-contact with the surface of the urethane layer. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a cleaning material, and more particularly, to a cleaning material suitable for removing foreign substances attached to an electronic component or the like.

  In recent years, electronic components such as hard disks and substrates have been refined, and highly functional electronic devices are being developed every day. In such a manufacturing process of an electronic device, if foreign matter adheres to the electronic component and the electronic device is assembled as it is, even a minute foreign matter of the order of submicron may hinder the operation of the electronic device. Therefore, in the manufacturing process of the electronic device, a cleaning process is provided as a post process for removing foreign matters and the like attached to the electronic component.

  As a cleaning member for removing foreign matter, there is a cleaning member having a functional layer formed on a base material layer, a member using ultrafine fibers for the functional layer, and an uneven structure by combining inorganic fine particles and a binder. Such members are known. In such a member, the foreign matter is removed by wiping the surface or the like while polishing the object to be cleaned in the sense of finishing. However, cleaning members with a functional layer that has an abrasive action may damage electronic parts that are objects to be cleaned, so the development of cleaning members that suppress the abrasive action of such functional layers and emphasize the removal of foreign substances Is underway.

  As a cleaning member with an emphasis on the foreign matter removing action, a cleaning member employing a resin layer as a functional layer has been proposed. In this member, foreign substances are removed by utilizing the adhesiveness, adhesiveness, or adsorptive property (hereinafter, also referred to as “adhesiveness”) of the resin layer. Generally, if the adhesiveness of the resin layer is increased, the foreign substance removal property is also increased. However, if the adhesiveness is increased too much, a part of the resin constituting the resin layer moves to the object to be cleaned and remains on the object to be cleaned (hereinafter this phenomenon is also referred to as “glue residue”). It may be difficult to remove the cleaning member from the substrate. On the other hand, if the adhesiveness is too low, foreign matter cannot be removed to a desired level, and there is a trade-off relationship between prevention of adhesive residue and ease of peeling and improvement of foreign matter removal performance.

  Accordingly, as a cleaning sheet that suppresses adhesive residue, for example, a cleaning sheet that removes foreign matter adhering to the probe needle tip of a probe card, the cleaning sheet has a cleaning layer, and the surface of the cleaning layer is cleaned. A cleaning sheet or the like containing a urethane polymer and a vinyl polymer has been proposed (see Japanese Patent Application Laid-Open No. 2004-304185). In addition, as an example in which the same technology is applied to a cleaning sheet that removes dirt attached to a paper conveyance system component of a recording apparatus such as an ink jet printer, an elastic cleaning layer having elasticity is provided on one surface of the support, A cleaning sheet having a pigment coating layer containing a pigment and a binder on the other side has been proposed (see JP-A-2006-175690).

  However, although the cleaning sheets described in these documents have a certain degree of foreign substance removal property, there is still room for improvement, and the cleaning sheets are not suitable for use in the post-process of manufacturing electronic devices and the like.

  Under such circumstances, it is desired to develop a cleaning material that is easy to peel off while suppressing adhesive residue on the object to be cleaned, has excellent foreign matter removal performance, and is easy to use in the subsequent process of manufacturing electronic devices, for example. ing.

JP 2004-304185 A JP 2006-175690 A

  The present invention has been made in view of the above circumstances, and its purpose is to remove foreign matters adhering to the object to be cleaned, particularly fine foreign matters on the order of submicrons, to reduce adhesive residue and to facilitate peeling. For example, it is to provide a cleaning material that is easy to use in a manufacturing process of an electronic device or the like.

The invention made to solve the above problems is
A cleaning material having a urethane layer on the surface,
The surface roughness Ra of the urethane layer surface is 0.005 μm or more and 0.1 μm or less, and foreign matters attached to the object to be cleaned are removed through surface contact with the surface of the urethane layer with respect to the object to be cleaned. Cleaning material.

  In the cleaning material, by the urethane layer having an appropriate hardness as the functional layer, it is possible to achieve both contradictory performances such as prevention of deterioration of foreign matter removal performance, reduction of adhesive residue and ease of peeling. In addition, since the surface roughness Ra of the urethane layer surface is 0.005 μm or more and 0.1 μm or less, the urethane layer can be in contact with sub-micron order foreign matter without unevenness, and as a result, foreign matter removal properties. Can be improved. In addition, it is easy to use because the surface of the urethane layer of the cleaning material only needs to be in contact with the object to be cleaned in order to remove minute foreign substances adhering to the object to be cleaned. It can be used suitably. Since the cleaning material employs a urethane layer and the polishing action on the object to be cleaned is reduced, foreign substances can be removed without damaging the object to be cleaned.

  The cleaning material further includes a base film, and the urethane layer is preferably laminated on at least one surface of the base film. Thereby, the cleaning material can be formed in a film shape, and can be easily applied to an object to be cleaned, so that the usability can be further improved.

  In the cleaning material, the urethane layer preferably has a JIS-A hardness of 60 or more and 98 or less. When the JIS-A hardness of the urethane layer is in the above range, the urethane layer can exhibit appropriate tackiness and the like, and as a result, the foreign matter can be improved by the cleaning material and the adhesive residue can be prevented and peeled off. It is possible to efficiently balance ease.

  In the cleaning material, the urethane layer preferably has a thickness of 0.1 μm or more and 40 μm or less. By making the thickness of the urethane layer in the above range, it is possible to ensure the adhesion of the urethane layer to the base film, and to effectively prevent the urethane layer from being damaged by contact with foreign matter, Moreover, a urethane layer can be formed economically.

  In the cleaning material, the urethane layer is preferably made of thermoplastic polyurethane. Thereby, the cleaning material can achieve reduction of adhesive residue and facilitation of peeling while exhibiting good foreign matter removability.

  The thickness of the cleaning material is preferably 10 μm or more and 400 μm or less. The cleaning material having a thickness in the above range has sufficient flexibility, so that it can be applied not only to a planar object to be cleaned, but also to removing foreign matters on an object to be cleaned having a curved surface such as a cylindrical shape, for example. Can do. As a result, the application target of the cleaning material can be expanded, and the usability in the process is also improved.

  In the cleaning material, the surface contact with the object to be cleaned is preferably flat contact. When the contact mode of the cleaning material with respect to the object to be cleaned is flat contact, the cleaning material and the object to be cleaned can be brought into contact with each other without unevenness, and foreign matter removability can be further improved.

  As described above, the cleaning material of the present invention has a high performance for removing fine foreign substances attached to an object to be cleaned such as an electronic component, reduces adhesive residue, and is easy to peel off. Can be used conveniently.

  The cleaning material of the present invention is a cleaning material having a urethane layer on the surface, the surface roughness Ra of the urethane layer surface is 0.005 μm or more and 0.1 μm or less, and the surface of the urethane layer surface with respect to the object to be cleaned Foreign matter adhering to the object to be cleaned through contact is removed. Hereinafter, each component will be described in order.

Urethane layer The cleaning material has a urethane layer on the surface, and this urethane layer serves as a functional layer in the cleaning material to directly contact the foreign material and remove the foreign material. The urethane layer may have a single layer structure, or a multilayer structure composed of the same or different materials.

  The constituent material of the urethane layer is not particularly limited as long as it is a polyurethane resin having a urethane bond or a resin composition containing this polyurethane resin. As the polyurethane resin, thermoplastic polyurethane is preferable from the viewpoint of imparting appropriate tackiness and peelability to the urethane layer. Examples of the thermoplastic polyurethane include polyester-based polyurethane (modified polyester urethane, water-dispersed polyester urethane, solvent-based polyester urethane, etc.), polyether-based polyurethane, polycarbonate-based polyurethane, and the like. The polyurethane resin may be of a self-emulsifying type or a forced emulsifying type. These polyurethane resins are generally obtained by reacting a polyol, a polyisocyanate, and, if necessary, a chain extender.

  Examples of the polyol include polyester polyol, polyester ether polyol, polycarbonate polyol, and polyether polyol. The number average molecular weight (Mn) of the said polyol is 300-8000 normally, Preferably it is 500-5000.

  The polyester polyol is a reaction product of a polycarboxylic acid and a polyol. For example, a polyester polyol obtained by a condensation reaction of a dicarboxylic acid or its ester compound or acid anhydride and a diol; ring opening of a lactone monomer such as ε-caprolactone Examples include polylactone diols obtained by polymerization. Examples of the dicarboxylic acid include aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid; aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid; hexahydroterephthalic acid. , Alicyclic dicarboxylic acids such as hexahydrophthalic acid and hexahydroisophthalic acid are used, and the above polyols include ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, 1,3-butanediol. 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,3-octanediol, 1,9-nonanediol Dihydric polyol such as glycerin, trimethylolpropane Trihydric amines such as triethanolamine, tetrahydric polyols such as diglycerin and pentaerythritol, hexavalent polyols such as sorbitol, octavalent polyols such as sugar, alkylene oxides corresponding to these polyols, aliphatic and alicyclic An addition polymer of aromatic amine, an addition polymer of alkylene oxide and polyamide polyamine, or the like is used. These polyester polyols may be used alone or in combination.

  The polyester ether polyol is a condensation reaction product of the aliphatic dicarboxylic acid, aromatic dicarboxylic acid, alicyclic dicarboxylic acid, or ester or acid anhydride thereof, and glycol such as diethylene glycol or propylene oxide adduct. Etc. These polyester ether polyols can also be used alone or in combination.

  Further, the polycarbonate polyol includes ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6- One or more polyhydric alcohols such as hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, diethylene glycol, ethylene carbonate, diethyl Examples include polycarbonate polyols obtained by reacting with carbonates and the like. Further, it may be a copolymer of polycaprolactone polyol and polyhexamethylene carbonate. These polycarbonate polyols may be used alone or in combination.

  Furthermore, as the polyether polyol, in addition to polyethylene glycol, polypropylene glycol, polytetramethylene glycol (PTMG) obtained by polymerizing cyclic ethers such as ethylene oxide, propylene oxide, and tetrahydrofuran, ethylene glycol, diethylene glycol, propylene glycol Dihydric alcohols or phenols such as dipropylene glycol, 1,3-butanediol, 1,4-butanediol, 4,4 ′-(dihydroxyphenyl) propane, 4,4 ′-(dihydroxyphenyl) methane, or Trihydric or higher polyhydric alcohols such as glycerin, 1,1,1-trimethylolpropane, 1,2,5-hexanetriol, pentaerythritol, ethylene oxide, Alkylene oxide, mention may be made of addition polymers such as butylene oxide, and alkylene oxide such as α- olefin oxide. These polyether polyols may be used alone or in combination.

  As other polyols, polyols whose main chain is composed of carbon-carbon bonds, such as acrylic polyols, polybutadiene polyols, polyisoprene polyols, hydrogenated polybutadiene polyols, AN (acrylonitrile) and SM (styrene monomers) are used as the above carbon-carbon polyols. Examples of the polyol include a polyol polymerized by polymerization, polycarbonate polyol, and PTMG (polytetramethylene glycol). These may be used alone or in combination. Among the above polyols, polyether polyols are preferable from the viewpoints of tackiness and flexibility.

  Examples of the polyisocyanate include aromatic polyisocyanate, aliphatic polyisocyanate, and alicyclic polyisocyanate. Examples of aromatic polyisocyanates include diphenylmethane diisocyanate (MDI), polymethylene polyphenylene polyisocyanate (crude MDI), tolylene diisocyanate (TDI), polytolylene polyisocyanate (crude TDI), xylene diisocyanate (XDI), and naphthalene diisocyanate. (NDI) and the like. Examples of the aliphatic polyisocyanate include hexamethylene diisocyanate (HDI). Examples of the alicyclic polyisocyanate include isophorone diisocyanate (IPDI). In addition, polyisocyanate obtained by modifying the above polyisocyanate with carbodiimide (carbodiimide-modified polyisocyanate), isocyanurate-modified polyisocyanate, urethane prepolymer (for example, reaction product of polyol and excess polyisocyanate, and isocyanate group And the like at the end). These polyisocyanates can be used alone or in combination.

  As the chain extender, a low molecular weight polyol is used, for example, ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentane. Diol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, diethylene glycol, 1,4-cyclohexanedimethanol, glycerin, etc. And an aliphatic glycol such as 1,4-dimethylolbenzene, bisphenol A, an ethylene oxide adduct of bisphenol A, and a propylene oxide adduct.

  Furthermore, it is good also as a constituent material of the said urethane layer by mixing thermoplastic polyurethane and another polymer. Examples of such other polymers include fluorine resins such as urethane-fluorine-containing polymer copolymers, (meth) acrylic resins, ethylene / vinyl acetate copolymers, and ethylene / (meth) acrylic acid copolymers. Ionomer, polyamide resin, polystyrene resin, polyolefin resin, polycarbonate resin, phenoxy resin, polyvinyl chloride resin, polyacetal resin, polybutylene terephthalate resin, acrylonitrile / butadiene copolymer, acrylonitrile / styrene copolymer, styrene / butadiene / styrene block Examples thereof include a copolymer, a styrene / isoprene / styrene block copolymer, and an ABS resin. The other polymer can be mixed or copolymerized in an amount of usually 1 to 200 parts by mass with respect to 100 parts by mass of the thermoplastic polyurethane.

  In addition, you may obtain the constituent material of the said urethane layer by mix | blending various additives with the resin composition containing the said thermoplastic polyurethane or thermoplastic polyurethane. Examples of the additive include fillers such as organic powders or inorganic powders; plasticizers such as aromatic esters and chlorinated paraffins; UV absorbers; antioxidants; colorants;

  In the cleaning material, the surface roughness Ra of the urethane layer surface is 0.005 μm or more and 0.1 μm or less. If the surface roughness Ra of the urethane layer surface is less than 0.005 μm, the urethane layer surface is too close to a perfectly flat surface, and foreign substances of various sizes are mixed. In particular, it becomes difficult to make contact with extremely small foreign matter. On the other hand, when the surface roughness Ra of the urethane layer surface exceeds 0.1 μm, the surface unevenness becomes excessively large, and it becomes difficult to remove the foreign matter that has entered the recesses on the surface of the counterpart material. In the cleaning material, since the surface roughness Ra of the surface of the urethane layer is set in the above range, the surface of the urethane layer is neither a perfect plane nor large unevenness. As a result, it is possible to make contact with a minute foreign matter attached to an object to be cleaned, particularly a submicron order foreign matter, without unevenness, and the foreign matter removability of the cleaning material is improved.

  As described above, the surface roughness Ra of the urethane layer surface of the cleaning material is 0.005 μm or more and 0.1 μm or less, preferably 0.008 μm or more and 0.08 μm or less, more preferably 0.01 μm. The thickness is 0.05 μm or less. By making the surface roughness Ra of the urethane layer surface 0.008 μm or more and 0.08 μm or less, it is possible to more efficiently achieve surface contact with the foreign material, and further improve the foreign material removability of the cleaning material. be able to. In addition, surface roughness Ra means centerline average roughness Ra obtained by measuring according to JIS B0651-2001.

Although the hardness of the said urethane layer is not specifically limited as long as a urethane layer shows moderate adhesiveness etc. and peelability, It is preferable that it is 60-98 as JIS-A hardness. By setting the JIS-A hardness of the urethane layer in the above range, the urethane layer has sufficient adhesiveness and the like to enable removal of foreign matters, and can be easily peeled off from the object to be cleaned. As a result, it is possible to efficiently achieve both the improvement of foreign matter removal by the cleaning material and the prevention of adhesive residue and the ease of peeling.
In addition, JIS-A hardness is the hardness measured using the type A durometer described in JIS K6253-2006.

  Although the thickness of the urethane layer in the cleaning material is not particularly limited, it is preferably 0.1 μm or more and 40 μm or less, and more preferably 1 μm or more and 20 μm or less. By making the thickness of the urethane layer 0.1 μm or more and 40 μm or less, the adhesiveness of the urethane layer to the base film is ensured, and the urethane layer is effectively prevented from being damaged by contact or bending with a foreign object. And a urethane layer can be formed economically. In addition, the thickness of the urethane layer is a value obtained by measuring the shortest distance from one surface of the urethane layer to the other surface at any 10 points on the surface of the cleaning material and averaging them in the cross section of the urethane layer. Say.

  The contact angle of the urethane layer with respect to water is not particularly limited, and may be determined in consideration of the adhesiveness of the urethane layer and the peelability. A preferable contact angle is 60 ° or more and 95 ° or less, and a more preferable contact angle is 65. It is not less than 90 ° and not more than 90 °.

Cleaning material As long as the cleaning material of the present invention has at least one surface capable of surface contact with the object to be cleaned, any of film shape, sheet shape, tape shape, rectangular parallelepiped shape, cubic shape, polyhedral shape, etc. It may be a form. Usually, the cleaning material is manufactured by laminating a urethane layer on the surface of a substrate having such a surface.

  Although the substrate is not particularly limited, it is preferable that the cleaning material further includes a substrate film. In this case, the cleaning material is preferably a thin film, and the urethane layer is preferably laminated on at least one surface of the substrate film. The shape of the cleaning material is determined according to the shape of the substrate film as the substrate, and can be changed according to the type of the object to be cleaned and the usage environment. In the present specification, the “film shape” is a concept including a sheet shape and a tape shape. Further, the shape of the cleaning material in plan view is usually rectangular but is not limited to this, and can be determined according to the shape of the object to be cleaned, such as a square, a polygon of pentagon or more, a circle, an ellipse, or the like. Furthermore, the urethane layer may be formed on a part of the urethane layer lamination surface of the base film, or may be laminated all over. Moreover, the urethane layer may be laminated not only on one side of the substrate film but also on both sides.

The base film The base film functions as a base layer for laminating the urethane layer while serving as a base of the cleaning material. In addition, although it is preferable that a base film has flexibility, it does not have flexibility according to the kind and usage condition of the to-be-cleaned object to apply, and itself may be rigid.

  The constituent material of the base film is not particularly limited as long as it exhibits strength that can be used after molding and can take a film-like form. Examples of the constituent material of the base film include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate; polyethylene (PE), polypropylene (PP), polyolefin having a cyclo or norbornene structure, ethylene Polyolefin resin such as propylene copolymer; Polyimide (PI); Polyetheretherketone (PEEK); Polyvinyl chloride (PVC); Polyvinylidene chloride resin; Polyamide resin such as nylon and aromatic polyamide; Polyurethane resin Polystyrene resins such as polystyrene and acrylonitrile / styrene copolymer (AS resin); acrylic resins such as polymethyl methacrylate; fluororesins; cellulose resins; polycarbonate resins; polyphenylenes Fido resins, vinyl alcohol resins; other thermoplastic resins such as polyvinyl butyral resin, can be exemplified thermosetting resins. Among these, polyester resins such as polyethylene terephthalate (PET) are preferable in view of affinity with the urethane layer, strength, and flexibility. The base film may have a single layer structure, but may have a multilayer structure made of the same or different materials.

  The thickness of the base film is not particularly limited, and may be determined in consideration of usability when cleaning an object to be cleaned. As thickness of a base film, it is 5 micrometers or more and 500 micrometers or less, for example, Preferably they are 10 micrometers or more and 300 micrometers or less, More preferably, they are 10 micrometers or more and 100 micrometers or less. By setting the thickness of the base film in the above range, the strength of the cleaning material can be maintained, and flexibility can be exerted to easily contact the object to be cleaned.

  In the cleaning material, the urethane layer may be directly laminated on the base film, and forms a base layer for improving the adhesion of the urethane layer to the base film and the weather resistance of the urethane layer. A urethane layer may be laminated through the formation layer. Examples of the constituent material of such an underlayer include a silane coupling agent.

  The thickness of the cleaning material may be determined in consideration of the type and shape of the object to be cleaned, workability in the process, etc., and is usually 5 μm or more and 600 μm or less, preferably 10 μm or more and 400 μm or less, more preferably Is 10 μm or more and 150 μm or less.

Method of Using Cleaning Material The cleaning material of the present invention is used so as to remove foreign matter adhering to the object to be cleaned through surface contact of the urethane layer surface with the object to be cleaned. Since the cleaning material employs the urethane layer as a functional layer, it is possible to efficiently remove foreign substances attached to the object to be cleaned simply by bringing the urethane layer into contact with the object to be cleaned.

However, when foreign matter removability at a higher level is required, after bringing the surface of the urethane layer of the cleaning material into contact with the object to be cleaned, a certain pressure is applied to the cleaning material to remove the foreign matter. It may be. By doing this, foreign matter is pushed into the urethane layer having an appropriate hardness and the contact area between the urethane layer and the foreign matter is increased, and the distance between the urethane layer and the object to be cleaned is shortened. Contact between the urethane layer and minute foreign matters other than the foreign matter pushed into the urethane layer also occurs, and as a result, the foreign matter removability can be improved. When removing foreign matter by applying pressure to the cleaning material, the pressure may be determined in consideration of the required degree of removal of foreign matter and the strength of the object to be cleaned, but 50 to 500 g / inch ² (7.6 × 10 ^{2 to} 7.6 × 10 ³ Pa) is preferable, 100 to 400 g / inch ² (1.5 × 10 ^{3 to} 6.1 × 10 ³ Pa) is more preferable, and 150 to 300 g / inch ² (2.3 ×). 10 ^{3 to} 4.6 × 10 ³ Pa) are particularly preferred.

  The aspect of the surface contact between the cleaning material and the object to be cleaned varies depending on the shape of the object to be cleaned, and as one aspect, the surface to be cleaned is a flat contact when the surface to be cleaned is a flat surface. When the surface to be cleaned is a part of the side surface of the cylindrical object to be cleaned, the contact is curved. In any case, the cleaning material can exhibit good foreign matter removal properties, but the surface contact with the object to be cleaned is preferably a flat contact. When the cleaning material and the object to be cleaned are in flat contact with each other, it is possible to prevent generation of a gap between the cleaning material and the object to be cleaned, and contact between the urethane layer and the foreign material between a plurality of foreign materials. The bias can be reduced, and as a result, the cleaning material can exhibit excellent foreign matter removability.

  In addition, it is only necessary to pass the surface contact with the object to be cleaned on the surface of the urethane layer in order to remove the foreign matter by the cleaning material, and as a subsequent procedure, the cleaning material may be peeled off as it is or a predetermined time has passed It may be peeled off later.

  The use mode in the case of using the cleaning material in the manufacturing process of an electronic device or the like is not particularly limited, and examples are as follows. For example, after an electronic component or the like conveyed by a line reaches the cleaning area where the cleaning material is disposed, the conveyance is temporarily stopped, and the cleaning material and the electronic component or the like are brought into surface contact to remove foreign matters. Alternatively, intermittent cleaning may be performed in which conveyance is started again. Further, the cleaning material is circulated between two rollers separated by a predetermined distance from the line, and the cleaning material is circulated while being synchronized with the conveyance speed. It may be a continuous cleaning in which a foreign object is removed by contacting the electronic component.

  The object to be cleaned by the cleaning material is not particularly limited, but for example, it is preferably used for an electronic component or the like in which a minute foreign matter such as a hard disk, an electronic substrate, a semiconductor, or a transistor is problematic. it can.

Manufacturing method of cleaning material The method of manufacturing the cleaning material of the present invention is not particularly limited. For example, a coating method in which a polyurethane solution is applied to a base film and dried to laminate a urethane layer, a urethane film formed in advance. And a reaction method of laminating a urethane layer by applying a polyurethane monomer solution on the substrate film and reacting the monomer by heating or radiation irradiation. Among these production methods, the coating method is preferable in view of easy adjustment of the thickness and surface roughness of the urethane layer and easy work.

  The solvent of the polyurethane solution (including the dispersion) in the coating method is not particularly limited as long as it is a solvent that dissolves or uniformly disperses the polyurethane resin, and examples thereof include an organic solvent, water, or a mixed solvent thereof. Examples of the organic solvent include tetrahydrofuran (THF), methyl ethyl ketone, isopropyl alcohol, toluene, N-methylpyrrolidone (NMP), methyl isobutyl ketone, and the like.

  The concentration of the polyurethane resin in the polyurethane solution may be determined as appropriate, and is usually 2 to 50% by mass, preferably 3 to 40% by mass in consideration of applicability to the base film (ease of thickness control, etc.). preferable. If it is less than 2% by mass, the solution viscosity is too low and it may be difficult to apply up to a predetermined thickness at one time. On the other hand, if it exceeds 50% by mass, the solution viscosity is too high. It may be difficult to laminate a urethane layer having a thickness of the same.

  The method of applying the polyurethane solution to the base film can also be selected as appropriate, and conventional methods such as bar coater method, roll coater method, air knife coater method, blade coater method, rod coater method, reverse coater method, comma coater Method, dip squeeze coater method, die coater method, gravure coater method, micro gravure coater method, dip method, silk screen coater method, spray method, spinner method and the like. Of these methods, the bar coater method and the gravure coater method are widely used.

  Subsequently, a urethane layer can be laminated | stacked by drying the coating film obtained by the said coating method. As drying temperature, it is 10-200 degreeC, for example, Preferably it is 20-160 degreeC, More preferably, it is 30-120 degreeC.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless departing from the gist of the present invention. Unless otherwise indicated, the numerical values in the examples include “mass%” including the table.

Preparation of cleaning material [Example 1]
A commercially available thermoplastic ether-based polyurethane as a polyurethane resin was dissolved in tetrahydrofuran (THF) to prepare a 13.6% by mass polyurethane solution. A polyethylene terephthalate (PET) film having a thickness of 100 μm and a thickness of 15 cm × 15 cm is prepared as a base film, and a polyurethane solution prepared thereon is used with a bar coater so that the thickness after forming the urethane layer is about 10 μm. Applied. Then, it dried at 110 degreeC and produced the cleaning material by laminating | stacking a urethane layer.

[Examples 2 to 7]
Using the commercially available polyurethane resin shown in Table 1, the cleaning materials of Examples 2 to 7 were prepared in the same manner as in Example 1. In Table 1, in Examples 6 and 7, a 13.6% by mass polyurethane solution was prepared using a polyurethane resin in which 10 parts by mass of a urethane-fluorine-containing polymer copolymer was mixed with 100 parts by mass of thermoplastic polyurethane. .

[Comparative Example 1]
Except that 1% by mass of acrylic fine particles “Chemisnow MX150” (manufactured by Soken Chemical Co., Ltd .; average particle size of 1 μm) was added to the thermoplastic ether polyurethane used in Example 1 with respect to the polyurethane solid content, it was the same as Example 1. A cleaning member was prepared.

[Comparative Example 2]
A cleaning member was produced in the same manner as in Comparative Example 1 except that the amount of the acrylic fine particles added was 5% by mass with respect to the urethane solid content.

[Comparative Examples 3 to 5]
Adhesive tapes or films of various commercially available materials were prepared and used as cleaning members.

The following polyurethane materials were used in the examples and comparative examples.
Thermoplastic ether-based polyurethane: “Milactolan E395” (manufactured by Nippon Milactolan),
Thermoplastic polycarbonate-based polyurethane: “Milactolan P985” (manufactured by Nihon Milactolan),
Thermoplastic ester-based polyurethane 1: “Milactolane E485” (manufactured by Nihon Milactolan),
Thermoplastic ester polyurethane 2: "Milactolane E665MZAA" (manufactured by Nihon Milactolan)
Thermoplastic ester-based (adipate) polyurethane: “Milactolan P185” (manufactured by Nihon Milactolan)
Urethane-fluorine-containing polymer copolymer: “Dialomer” (manufactured by Dainichi Seika Kogyo Co., Ltd.)

Evaluation of physical properties About cleaning materials prepared in Examples and cleaning members prepared or prepared in Comparative Examples (hereinafter also referred to as “cleaning materials”), surface roughness (Ra), JIS-A hardness, contact The corner, tack force, foreign matter removal property and adhesive residue were evaluated.

[Measurement of surface roughness Ra]
The surface roughness Ra was measured using a small surface roughness meter (“FORM TRACER SV-S3000”, manufactured by Mitutoyo Co., Ltd.). Measurement was performed at 0.5 μm, and the center line average roughness Ra was calculated.

[Measurement of JIS-A hardness]
Based on JISK6253, it measured using the type A durometer. The sample was 6 mm thick by stacking three sheets of 2 mm thickness. The cleaning members of Comparative Examples 3 and 4 are commercially available film-like samples, and a sheet with a thickness of 2 mm cannot be prepared, so the JIS-A hardness could not be measured.

(Measurement of contact angle)
The contact angle was measured using a contact angle meter CA-A type (manufactured by Kyowa Interface Science). A water droplet having a diameter of 2 mm was dropped on the cleaning material or the like. 30 seconds after dropping, a value twice as large as the angle with respect to the surface of the straight line of the cleaning material or the like connecting the left and right end points and the apex of the droplet was read as the contact angle, and the average value on the left and right was taken as the contact angle.

[Measurement of tack force]
Evaluation was performed using a PICMA tack tester (manufactured by Toyo Seiki). Specifically, the cleaning material of Example 1 and the film to be the control sample are each affixed to a preparation so as to be 1 inch square. The preparation with the cleaning material of Example 1 attached is attached to the base with a double-sided tape, and the control sample is attached to the measurement jig side. Thereafter, the measuring jig is lowered at a descending speed of 30 cm / min, and when the load reaches 500 g by contacting the cleaning material affixed to the base, the descent is stopped and the measuring jig is maintained for 10 s. Was raised at a rising speed of 100 cm / min. The load at the time when the cleaning material of Example 1 and the film as the control sample were peeled was measured and used as the tack force. By measuring the tack force, it can be used as an index of relative peelability between samples. This procedure was similarly performed for each of the examples and comparative examples.

[Evaluation of foreign substance removal]
When observing with the surface appearance macro inspection device Micromax VMX-2300 (made by Vision Cytec Co., Ltd.), on the Al-Ni substrate (surface), the white area displayed in white in the observation screen is 1% in area ratio. Alumina fine particles (average particle diameter of about 0.5 μm) were deposited on the roughness Ra: about 1 mm (the area where the alumina particles are present is displayed in white on the observation screen). A cleaning material or the like was brought into contact with the surface from above, a pressure of 200 g / in ² (3.04 × 10 ³ Pa) was applied for 10 seconds, and then the cleaning material or the like was peeled off. The area ratio of the white area after the treatment with the cleaning material or the like to the observation screen was evaluated using the above-mentioned micromax. When the area ratio of the white region was 0.1% or less when observed with the above micromax, “◯” was indicated, and otherwise, “x” was indicated.

[Evaluation of adhesive residue]
A cleaning material or the like was brought into plane contact with an Al—Ni substrate (surface roughness Ra: about 1 mm), a pressure of 200 g / in ² (3.04 × 10 ³ Pa) was applied for 10 seconds, and then the cleaning material and the like were peeled off. Thereafter, the adhesive residue was evaluated using the above micromax. If the white area (the area where the adhesive residue is present is displayed in white on the observation screen) is 0.1% or less in area ratio when observed, “○” In other cases, “x” was assigned.
Each evaluation result is shown in Table 1.

  From the results shown in Table 1, in the cleaning material according to the example in which the urethane layer having the predetermined surface roughness Ra was laminated on the base film, the adhesive residue was reduced while exhibiting excellent foreign matter removal, and peeling The property was also good. On the other hand, in Comparative Examples 1 and 2 in which the urethane layer was laminated but the surface roughness Ra was large, the adhesive residue was reduced, but the foreign matter removability was poor. In Comparative Examples 3 to 5 using commercially available products in which no urethane layer was laminated, either the foreign matter removing property or the adhesive residue property did not satisfy the evaluation criteria. In particular, in Comparative Example 3 using a commercially available product, an adhesive residue was generated because the contact angle was too small. Similarly, in Comparative Example 4 using a commercially available product, the contact angle was too large and the adhesiveness was low, resulting in poor foreign matter removal. Furthermore, in Comparative Example 5 using a commercially available product, it was because a bleed material from the silicon sheet was seen, resulting in a paste residue.

  As described above, the cleaning material of the present invention is excellent in removing foreign matters and has a reduced adhesive residue and can be easily peeled off. It can be suitably used as a cleaning material.

Claims (7)

A cleaning material having a urethane layer on the surface,
The surface roughness Ra of the urethane layer surface is 0.005 μm or more and 0.1 μm or less, and foreign matters attached to the object to be cleaned are removed through surface contact with the surface of the urethane layer with respect to the object to be cleaned. Cleaning material. Furthermore, a base film is provided,
The cleaning material according to claim 1, wherein the urethane layer is laminated on at least one surface of the base film.   The cleaning material according to claim 1 or 2, wherein the urethane layer has a JIS-A hardness of 60 or more and 98 or less.   The cleaning material according to claim 1, wherein the urethane layer has a thickness of 0.1 μm or more and 40 μm or less.   The cleaning material according to any one of claims 1 to 4, wherein the urethane layer is made of thermoplastic polyurethane.   The cleaning material according to claim 1, wherein the thickness is 10 μm or more and 400 μm or less. The cleaning material according to any one of claims 1 to 6, wherein the surface contact with the object to be cleaned is flat contact.