JP2003103471A - Polishing sheet having elastic layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive and resource saving polishing sheet superior in polishing performance with a pad function of applying finish polishing to a surface or an end face of a precision component such as a magnetic head, magnetic and optical discs, a semiconductor wafer, flattening of a semiconductor integrated circuit, an optical lens or an optical fiber. SOLUTION: The polishing sheet has a polishing layer in one face of a base material film 11 and it is provided with the elastic layer 63 in another face. It is characterized by that an elastic degree of the polishing sheet is adjusted by material and thickness of the base material film, the elastic layer and/or an adhesive layer by integrally providing the elastic layer via the adhesive layer 61 by a simple process, forming the polishing layer with an optional pattern necessary in usage for polishing, and providing a pressure sensitive adhesive layer 71 on the elastic layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head, a magnetic and optical disk, a semiconductor wafer, a flattening when a semiconductor integrated circuit is formed, a polishing for finishing a surface or an end surface of precision parts such as an optical lens and an optical fiber. Regarding the sheet, more specifically, it is possible to polish the ferrule part and the optical fiber part at the same time by polishing the end face of the optical connector part, and the hardness of the polishing surface plate of the polishing machine used and the polishing surface of the material to be polished. The present invention relates to a polishing sheet with a pad function that improves the polishing accuracy of a polishing surface without being affected by the shape.

[0002]

2. Description of the Related Art Conventionally, as a polishing sheet, diamond is used as a polishing agent, or chromium oxide is used in combination, as disclosed in JP-A-63-185579 and JP-A-5-30.
Japanese Patent Application Laid-Open No. 8-33364 and Japanese Patent Application Laid-Open No. 8-267364 disclose polishing sheets using alumina and silica as polishing agents for polishing by pressing while rotating an optical connector.
No. 6,758, JP-A-6-278038 and JP-A-2001-138249 disclose a polishing sheet in which a binder of a polishing layer is made porous to have elasticity. Further, JP-A-5-228844 discloses that the Young's modulus of the base material of the polishing sheet is specified, and JP-A-2000-2000 uses a rigid steel plate as the base material of the polishing sheet.
-61848 discloses an apparatus and a polishing tape which bring a polishing tape into contact with a guide surface having a concave arc shape to polish a material to be polished into a convex shape.
A polishing sheet with a pad including a polishing layer / hard element / elastic element (pad function) is disclosed in Japanese Patent Publication No. 2001-505489.

However, the above-mentioned Japanese Patent Laid-Open No. 63-185.
The polishing sheets of 579, JP-A-5-309571, JP-A-8-267364, and JP-A-8-336758 each have a base film provided with a polishing layer. Further, the polishing sheets disclosed in JP-A-6-278038 and 2001-138249 have the purpose of providing a cushioning effect on the material to be polished.
In the polishing sheets of JP-A-28844 and JP-A-2000-61848, the base film is made to have rigidity, and in the above publications, there is no mention of the pad function of the polishing sheet itself. There is.
In Japanese Unexamined Patent Application Publication No. 2001-18156, a concave portion is formed in the device, and the polishing sheet itself does not have a pad function. Further, JP-A-2001-505489 discloses a polishing sheet with a pad function, but the formation of a polishing layer having a three-dimensional predetermined surface pattern is complicated, and the polishing sheet / hard element / elastic element is sequentially formed by an adhesive. There is a drawback in that there are many manufacturing processes because they are pasted together.

[0004]

Therefore, in order to solve such problems, the present invention provides an elastic layer having a polishing layer on one surface of a base film and a pad function on the other surface. With the abrasive sheet provided, the elastic degree can be adjusted by the material and thickness of the elastic layer and / or the adhesive layer, and the idea that the elastic layer is integrally provided through the adhesive layer in a simple process is adopted. The invention was completed.

[0005]

In order to solve the above problems, the gist of the first invention is to provide a polishing having a polishing layer on one surface of a base film and an elastic layer on the other surface. In the sheet, the elastic layer is integrally provided via an adhesive layer. A second aspect of the invention is to form the polishing layer in an arbitrary pattern required for polishing, and a third aspect of the invention is to provide an adhesive layer on the elastic layer.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic plan view of a polishing sheet showing one embodiment of the present invention. FIG. 2 shows A of FIG.
FIG. In the polishing sheet 10 of the present invention, the polishing layer 15 is provided on one surface of the base film 11 directly or via the primer layer 13, and the elastic layer is provided on the other surface of the base film 11 via the adhesive layer 71. 63 is provided. In particular, the base film 11, the adhesive layer 61, and the elastic layer 63
Are collectively referred to as a base material layer 50, and the elasticity and hardness of a polishing sheet suitable for polishing a material to be polished to be described later are adjusted by each material and thickness of the base material layer 50 and a combination thereof. it can. Here, elasticity is a function of flexibility represented by compressibility and bending elasticity, and hardness is a function of hardness represented by Young's modulus.

The substrate film 11 can be appropriately selected from a film having less lubricant and mechanical strength during polishing, strength and heat resistance to withstand coating / drying of the polishing agent, and less dimensional change.
For example, polyolefin such as high-density polyethylene / polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyacrylonitrile, polyamide, acrylic resin containing acrylic acid ester or methacrylic acid ester as a main component. It is a stretched or unstretched film made of resin, polyester such as polyethylene terephthalate / polybutylene terephthalate / polyethylene naphthalate, polyacetal, polyarylate, cellulose derivative such as di- or tri-cellulose acetate, and polycarbonate.

Particularly, a polyethylene terephthalate film which is excellent in coating suitability for polishing layer, suitability for post-processing and handling in a polishing machine is preferable. The thickness of the plastic film may be appropriately selected depending on the material, size, thickness and the like of the material to be polished, and the thickness is, for example, 25 to 250 μm.
m. An antistatic agent may be added to the base material film 11 in order to prevent the adhesion of dust in the working process. As the antistatic agent, a known nonionic surfactant, anionic surfactant, cationic surfactant or the like, polyamide derivative or acrylic acid derivative or the like is appropriately selected and added.

Next, the polishing layer 15 is applied to one surface of the base film 11. On the side to which the polishing layer 15 is applied,
In order to improve the adhesiveness between the both, it is preferable to perform the primer layer 13 or an easy adhesion treatment such as corona discharge treatment or ozone gas treatment. In particular, the primer layer 13 improves the adhesiveness to the polishing layer 15, prevents the binder 17 and the polishing particles 19 from falling off, and enables stable polishing work. For example, polyurethane, polyester, polyvinyl chloride resin, Vinyl acetate resin, vinyl chloride-vinyl acetate copolymer, acrylic resin, polyvinyl alcohol resin,
A polyvinyl acetal resin, a copolymer of ethylene and vinyl acetate, acrylic acid, or the like, an epoxy resin, or the like can be used.

These resins are appropriately dissolved or dispersed in a solvent to prepare a coating solution, which is applied to the base film 11 by a known coating method and dried to form the primer layer 13. In addition, a resin, a monomer, an oligomer, a prepolymer, and the like, and a reaction initiator, a curing agent, a crosslinking agent, or the like are appropriately combined, or a main agent and a curing agent are combined,
It may be formed by coating and drying, and then reacting by aging treatment after drying or drying. The primer layer 13 has a thickness of about 0.05 to 10 μm, preferably 0.1 to 5 μm.

Next, the polishing layer 15 laminated on the surface of the primer layer 13 comprises abrasive particles 19 and a binder 17. In general, an ink in which abrasive particles 19 are dispersed in a resin solution to be the binder 17 is applied by a printing means, dried, and if necessary, further heated and cured to form. The thickness of the polishing layer 15 is 2 μm to 30 μm, though it depends on the particle diameter of the polishing particles used.

As the abrasive particles 19, for example, silica (silicon oxide), alumina, silicon carbide, diamond, iron oxide, chromium oxide, zirconium oxide, cerium oxide,
Titanium oxide, silicon nitride, antimony oxide, boron nitride,
Lithium silicate etc. can be used individually or in combination of 2 or more types. For polishing glass materials and optical fibers, diamond, alumina, iron oxide,
Carborundum, chromium oxide, and cerium oxide are suitable, and diamond having high hardness is particularly suitable. The average particle size of the abrasive particles 19 is 0.005 μm to 10 μm.
A range of m is preferred.

As the binder 17 of the polishing layer 15, a resin having a siloxane bond, a polyester resin, a polyvinyl chloride resin, a polyvinyl acetate resin, a polyacrylic resin, a polyvinyl alcohol resin, a polyethylene resin, a polyvinyl acetal. Resins, rubbers and derivatives thereof, polyamide resins, vinyl chloride-vinyl acetate copolymer resins, etc. can be applied. Also, normally, the binder 1
The fine inorganic particles of the abrasive particles 19 may be mixed in a ratio of about 100 to 1400 parts by weight with respect to 100 parts by weight of the 7 resin.

Further, the solvent of the ink for forming the polishing layer 15 is, for example, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, ethanol, isopropyl alcohol, anone, etc., depending on the kind of binder resin. Is used as a single solvent or a mixed solvent of two or more of these, and if necessary, a viscosity modifier, a dispersant, an antistatic agent, a plasticizer,
Pigments may be added, and an ink having a viscosity and printability suitable for screen printing is prepared.

The abrasion resistance and solvent resistance of the polishing layer 15,
In order to improve the heat resistance and improve the adhesion between the polishing layer 15 and the base film 11 or the primer layer 13, an isocyanate-based curing agent is added to the ink for forming the polishing layer. You may add. As the curing agent, for example, an isocyanate curing agent such as tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI) can be applied, and active hydrogen of the binder resin in the ink can be used. Having functional groups (-OH, -NH2, -COOH, etc.)
Layer 15 made of a curable resin layer obtained by reacting a curing agent with a curing agent
Is preferred. The addition amount of this isocyanate-based curing agent is represented by the equivalent ratio of the isocyanate group (-NCO) of the isocyanate-based curing agent and the functional group in the binder resin, that is, [(-NCO) / functional group in the binder resin]. The equivalent ratio is preferably in the range of 0.5 to 10.

FIG. 3 is a schematic plan view of a polishing sheet showing one embodiment of the present invention of claim 8. FIG. 4 is a BB sectional view of FIG. The shape of the polishing layer 15 may be formed in an arbitrary pattern required at the time of polishing use, and is the present invention of claim 8. The shape of the polishing layer 15 is not particularly limited, and may be appropriately formed according to the shape of the material to be polished and the polishing method. In the example of FIG. 3, the outer peripheral portion 21 on which the polishing layer is not formed is a portion that is not used when polishing the material to be polished.
And the inner peripheral portion 23 where the polishing layer is not formed are concentric and the polishing layer portion has a donut pattern.
The shape of the polishing layer 15 is not particularly limited and may be appropriately formed according to the shape of the material to be polished.

Comparing the area of the polishing layer of the polishing sheet of the present invention of claim 8 in FIG. 3 with the invention of claim 1 in FIG. 1, a significant reduction of several tens% is achieved. You can The areas of the outer peripheral portion 21 and the inner peripheral portion 23 where the polishing layer is not formed vary depending on the size of the material to be polished and the polishing machine used, but in any case, the area of the polishing layer of the present invention according to claim 8 is , Can be significantly reduced.

FIG. 5 is a schematic plan view of a polishing sheet showing an embodiment of the present invention according to claim 9. FIG. 6 is a sectional view taken along line CC of FIG. In the polishing sheet 10 of the present invention of claim 9 of FIG. 5, the polishing layer 15 has a concentric donut-shaped pattern excluding the outer peripheral portion 21 and the inner peripheral portion 23, and the center of rotation of polishing is centered. 5 has one or a plurality of concentric circular recesses and two concentric grooves 41 in the example of FIG. 5, but FIG. 5 shows the concept in a schematic diagram, and the dimensions are for explanation. Exaggerated. The groove 41 may have a width of 0.1 μm to 1 as long as it can accommodate polishing dust and fallen abrasive particles.
The groove depth is about 0 mm, preferably 1 μm to 5 mm, and the maximum polishing layer thickness, but is about 0.1 μm to 30 μm, preferably 0.5 μm to 10 μm. May be appropriately selected depending on the size of the polishing layer, the thickness of the polishing layer, and the like.

FIG. 7, FIG. 8, FIG. 9, FIG. 10, and FIG. 11 are plan views showing an embodiment of the present invention of claim 9. In addition to the concentric circle shape of FIG. 5, the groove shape is a polka dot shape of FIG. 7, a radial shape of FIG. 8, a spiral shape of FIG. 9, a hexagonal pattern of FIG.
Various groove shapes such as diagonal lines can be applied. The groove shape is
It may be appropriately selected from the material and size of the material to be polished, the content of polishing such as finishing and rough polishing, the lubricant and the polishing liquid for chemical mechanical polishing.

Polka dot, radial, spiral, turtle pattern,
Since the groove shape such as diagonal lines does not form a closed circuit, the polishing scraps that are generated during the polishing operation and that are trapped and the abrasive particles that have fallen off are actively discharged from the polishing layer surface, and further polishing is performed. It is also discharged from the sheet. In this way, polishing debris and fallen abrasive particles do not come into contact with the material to be polished, and the material to be polished is the magnetic head, magnetic and optical disk, semiconductor wafer, semiconductor integrated circuit, optical lens,
It is possible to extremely reduce scratches on the optical fiber.

In order to provide the polishing layer 15 on the entire surface of the first aspect, known coating methods such as roll coating, reverse roll coating, gravure coating, gravure reverse coating, bar coating and comma coating can be applied. With the coating method,
The above-described ink for forming the polishing layer 15 is applied directly to the base film or on the primer layer, dried, and if necessary, aged to form the polishing layer 15.

Further, screen printing, gravure printing, gravure offset printing, or the like can be applied to provide the polishing layer 15 in any pattern shape of claim 8, and screen printing is preferable. By the screen printing method, the above-described ink for forming the polishing layer 15 is used to form the polishing layer 15 having a pattern shape. As a plate material for screen printing, a silk screen plate, a stainless plate, a nickel plate, etc. can be applied. An emulsion is applied to the screen plate to prepare, for example, a doughnut-shaped original document having the polishing layer 15 shown in FIG. 5, exposed, washed out, and made into a screen printing plate. Polishing layer 1 prepared above
5. The substrate film 11 is superposed on the screen printing plate containing the forming ink, and the squeegee is moved while pressing to print. The predetermined polishing layer 15 can be obtained by appropriately adjusting the hardness of the squeegee, the angle, the moving speed, the viscosity of the ink, the thixotropic property, the thickness of the emulsion of the printing plate, and the like.

In this way, the patterned polishing layer 15 is obtained. For example, in the case of the doughnut-shaped polishing layer shown in FIG. 5, the area of the polishing layer is significantly reduced by about several tens of percent as compared with the entire polishing layer. . That is, a valuable and expensive material such as diamond contained in the ink can be effectively used. In addition, since the area required for the polishing work is covered, the precision of the polishing and the polishing work will not be affected.

Further, since the polishing layer 15 is formed by the screen printing method, a pattern of screens peculiar to the screen printing appears on the surface of the polishing layer 15 to form a mesh surface. The mesh-like shape is a fine surface irregularity shape, and a liquid lubricant such as water described later is evenly distributed, and polishing debris is buried in the recesses, so that polishing performance can be stably improved.

As the elastic layer 63, those which are not hard and brittle such as ceramics and glass can be applied. For example, polyolefin, polystyrene, polyvinyl chloride, polyacrylonitrile, polyamide, acrylic resin, polyethylene terephthalate / polybutylene terephthalate / polyethylene Stretched or unstretched film made of polyester such as phthalate, polyacetal, polyarylate, cellulosic resin, organic polymer such as polycarbonate, foam such as polystyrene / polyurethane, nonwoven fabric such as polyethylene / polyamide / polyethylene naphthalate, or impregnation A single layer of paper such as paper and mixed paper, or a laminated body thereof is suitable. By selecting the material and the thickness thereof, as will be described later, the elasticity and hardness of the polishing sheet suitable for polishing the material to be polished are adjusted.

In order to integrate the elastic layer 63 on the surface of the base film 11 on which the polishing layer 15 is not formed, the dry lamination method or the non-solvent lamination method of claim 3 or the extrusion lamination method of claim 4 is used. Applicable. The dry lamination method or the non-solvent lamination method is used for the polishing layer 15 of the base film 11.
An adhesive is applied to the non-abrasive surface and dried if necessary to stack the elastic layer 63 on the non-abrasive surface 15. After the lamination, the necessary treatment is performed depending on the type of the adhesive described below to adhere them.

As an adhesive agent for the adhesive layer 61 used in the dry lamination method or the non-solvent lamination method, an adhesive agent which is cured by heat, ultraviolet rays or electron beams can be applied. Specific examples of the thermosetting adhesive include a two-component curing type urethane adhesive, a polyester urethane adhesive,
Polyether urethane adhesives, acrylic adhesives, polyester adhesives, polyamide adhesives, polyvinyl acetate adhesives, epoxy adhesives, rubber adhesives, etc. can be applied, but two-component curing type urethane System adhesives are preferred.

The two-component curing type polyurethane resin is, for example, a polymer obtained by reacting a polyfunctional isocyanate with a hydroxyl group-containing compound, specifically, for example, tolylene diisocyanate. Nart,
Aromatic polyisocyanate such as diphenylmethane diisocyanate, polymethylene polyphenylene polyisocyanate, or hexamethylene diisocyanate,
Reaction of polyfunctional isocyanate such as aliphatic polyisocyanate such as xylylene diisocyanate with hydroxyl group-containing compound such as polyether type polyol, polyester type polyol and polyacrylate polyol The two-component polyurethane resin obtained by the above can be used.

In the dry lamination method, an adhesive composition containing these as main components is dissolved or dispersed in an organic solvent, and this is subjected to, for example, roll coating, reverse roll coating, gravure coating, gravure. It is applied by a coating method such as reversing coating, gravure offset coating, kiss coating, wire bar coating, comma coating, knife coating, dip coating, flow coating, spray coating, etc., and is dried with a solvent, etc. The adhesive layer 61 for application can be formed. Preferably, roll coating and reverse rolling
This is the rucoating method.

The thickness of the adhesive layer 61 is 0.1-2.
0 μm (dry state), preferably 1.0 to 5.0 μm
m. As soon as the adhesive layer 61 is formed, the elastic layer 6
After 3 is laminated, aging is performed at 30 to 120 ° C. for several hours to several days, whereby the adhesive is hardened to bond. When using a material of the elastic layer 63, for example, a non-absorbent material such as an organic polymer sheet or a film, an adhesive is applied to the elastic layer 63 side, and the base film 11 surface is laminated, It may be glued.

The non-solvent lamination method is basically the same as the dry lamination method, but the adhesive composition is used as it is without dissolving or dispersing the adhesive composition in an organic solvent. In order to reduce the viscosity, the adhesive composition may be heated and heated before use.

The same adhesive can be applied to the ionizing radiation curable adhesive which is cured by ultraviolet rays or electron beams,
A photopolymerization initiator may be added in the case of ultraviolet curing, and may not be added in the case of electron beam curing with high energy. The ionizing radiation curability is exhibited by containing a compound having a radical polymerizable unsaturated double bond. For example, a monofunctional monomer such as styrene, methylstyrene, (meth) acrylic acid or an alkyl or aryl ester thereof, a difunctional or higher functional compound such as ethylene glycol, glycerin, pentaerythritol, or an epoxy resin may be added to (meth) acrylic acid or Bifunctional or higher functional (meth) acryloyl monomer obtained by reacting the derivative, polyurethane type, polyester type, polyether type having a radical polymerizable double bond such as (meth) acryloyl group in the molecule,
Polycarbonate-based, poly (meth) acrylic acid ester-based oligomers or prepolymers, etc., to some extent, for example, 5% based on the total amount of adhesive, preferably 10-90
%, More preferably 20 to 60%, to impart ionizing radiation curability.

As a particularly preferable compound having a radical-polymerizable unsaturated double bond, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, a part or the whole thereof, 1,6 Hexanediol diglycidyl ether di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipenerythritol hexa (meth) acrylate, etc. It is preferable to use a polyfunctional monomer having a functionality or higher, or to use a urethane (meth) acrylate oligomer having a molecular weight of about 300 to 5000 as a part or the whole thereof. further,
It is preferable to use both in combination. To the adhesive composition, if necessary, additives such as colorants such as dyes and pigments, luster modifiers, fillers such as extenders, defoamers, leveling agents, thixotropic agents are added. Is also good.

The electron beam curing adhesive is formed by applying the adhesive composition to the surface of the base film 11 which is not the polishing layer by the dry lamination method or the non-solvent lamination method described above. As the coating amount, in a dry state,
About 0.5 to 30 μm, preferably 1.0 to 10 μm
Is. An elastic layer 63 is formed immediately after the adhesive layer 61 is formed.
After being laminated, it is cured by irradiation with ionizing radiation such as ultraviolet rays and electron beams.

For curing the electron beam curing adhesive, various electron beam accelerators such as Cockloft-Walton type, Van de Graaff type, resonance transformer type, insulating core transformer type, linear type, dynamitron type, high frequency type and the like are used. Irradiate with an electron beam. The irradiation dose of the electron beam is usually 100 to 1000 keV,
Electrons having an energy of 100 to 300 keV are preferably applied at a dose of about 1 to 300 kGy. If the irradiation amount is less than 1 kGy, curing may be insufficient, and if the irradiation amount exceeds 300 kGy, the cured coating film or substrate may be damaged. Further, the atmosphere for curing is carried out at an oxygen concentration of 500 ppm or less, and normally it is preferable to carry out at about 200 ppm.

Further, for curing the ultraviolet curable adhesive, a photopolymerization initiator such as acetophenones, benzophenones, Michler benzoyl benzoate, α-amyloxime ester, tetramethylmeuram monosulfide is added to the adhesive composition. , A photopolymerization initiator such as thioxanthone and, if necessary, a photosensitizer such as n-butylamine, triethylamine, and tri-n-butylphosphine. A high pressure mercury lamp or a metal halide lamp can be applied to the UV lamp used for curing the ultraviolet curable adhesive, and the wavelength of the ultraviolet ray is about 200 to 450 nm, and the wavelength may be selected according to the adhesive composition. The irradiation amount is determined according to the output of the UV lamp and the lamination speed.

In the extrusion lamination method of claim 4,
Examples of the adhesive layer 61 for melt extrusion lamination include polyethylene (low density, linear), polypropylene,
Olefin resin such as polybutene, olefin copolymer resin such as ethylene-propylene copolymer / ethylene-butene copolymer, ethylene-vinyl acetate copolymer (E
VA), ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-acrylic acid copolymer (EAA), ethylene-methyl acrylate copolymer (EMA), ethylene A copolymer resin of an olefin such as methacrylic acid copolymer (EMAA) / ethylene-methyl methacrylate copolymer (EMMA) with another monomer, an ionomer obtained by metal-crosslinking an ethylene-unsaturated acid copolymer, polyethylene, or Acid-modified polyolefin resin obtained by modifying polyolefin resin such as polypropylene with unsaturated carboxylic acid such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, or ethylene-propylene copolymer rubber -Ethylene-propylene-non-conjugated diene rubber-Ethylene-butadien And thermoplastic elastomers such as elastic copolymer mainly composed of olefins such as copolymers can be applied. These may be used alone or as a mixture (blend) or a laminate of two or more kinds.

As the resin, one or more kinds of resins can be mixed or used as a laminate.
When the laminate is formed, it is formed by a multi-layer coextrusion method, using 2 layers of 2 types,
It is also possible to have a layer structure such as 2 types 3 layers and 3 types 5 layers.
Preferred are low density polyethylene, linear low density polyethylene, ethylene-vinyl acetate copolymer, ionomer resin, and copolymer resin of olefin and other monomer.
As the linear polyethylene, specifically, an ethylene-α-olefin copolymer polymerized by using a metallocene catalyst can be used.

The adhesive layer 61 for melt extrusion lamination includes a thermoplastic elastomer such as diene rubber, hydrogenated diene rubber, ethylene-propylene copolymer rubber / ethylene-propylene / non-conjugated diene rubber / ethylene. -The hardness degree (flexibility) is adjusted by mixing an olefin elastomer such as an elastic copolymer having an olefin as a main component such as a butadiene copolymer, an ethylene-propylene-butene copolymer resin, and a soft polypropylene. Is also good. Further, a colorant, a plasticizer, a filler, etc. may be added.

Adhesive layer 6 for melt extrusion lamination
1 was first melted in an extruder with an externally heated end,
Expand it in the required width direction with a die and push it out like a curtain. The melt adhesion layer 61 is laminated by guiding the base material film 11 and the elastic layer 63 between the same sandwiching rolls and allowing the base material film 11 and the elastic layer 63 to flow down to the middle. The method of so-called extrusion coating by those skilled in the art is used to simultaneously form and laminate the adhesive layer 61. The thickness of the adhesive layer 61 for melt extrusion lamination is about 5 to 200 μm, more preferably 10 to
It is about 100 μm.

When it is necessary to obtain a stronger adhesive strength during the above-mentioned lamination, an anchor coating agent,
For example, an adhesion improver such as an organic titanium-based anchor coating agent such as alkyl titanate, an isocyanate-based anchor coating agent, a polyethyleneimine-based anchor coating agent, or a polybutadiene-based anchor coating agent is applied. The anchor coating agent is applied by a known coating method such as roll coating or gravure coating and dried to form an anchor coating agent layer. If necessary, the base film 11 and / Alternatively, it may be provided on the elastic layer 63. As the coating amount of the anchor coating agent,
It is preferably about 0.1 to 5.0 μm (dry state).

FIG. 12 is a schematic sectional view of a polishing sheet showing an embodiment of claim 10. At the time of actual polishing work, a liquid lubricant such as water is dropped between the material to be polished and the polishing sheet, but the lubricant may flow to unnecessary portions,
There is a problem that the surface of the required polishing layer cannot be evenly distributed. To this end, at least the polishing layer 1 of the polishing sheet 10
Although the water-repellent layer 32 is provided on the outer peripheral portion 21 where 5 is not formed, it may be provided on the inner peripheral portion 23 and / or the groove portion 41. Even if the water-repellent layer 32 has a smaller thickness, the water-repellent layer 32 is repelled by a liquid lubricant such as water and consequently dammed to the surface of the polishing layer 15 due to its water-repellent performance. The polishing is performed evenly and stably. In addition, the water repellent layer 3
When 2 is provided in the inner peripheral portion 23, the lubricant that is usually dropped to the central portion has an effect of spreading from the central portion to the peripheral portion and being evenly distributed to the polishing layer at an early point in the initial polishing.

As the material of the water repellent layer 32, polyester resin, vinylidene chloride resin, vinyl chloride resin, polyethylene resin, polypropylene resin, silicone resin, fluorine resin, WAX or the like can be applied, and particularly, the surface tension is Polyethylene resin, polypropylene resin, silicone resin, fluorine resin, WAX, etc., which are small and have a surface tension of 400 μN / cm or less, are suitable because they easily repel liquid lubricants such as water. Alternatively, these water repellent materials may be dispersed or dissolved in a binder, printed on the entire surface or in a pattern, and dried. In addition, bank layer 3
Since the surface tension of No. 1 also has an effect of height difference of the bank, the surface tension may be 400 μN / cm or more. For example, if the lubricant is water (surface tension 760 μN / cm), it may be less.

In order to provide the water-repellent layer 32 in a pattern, screen printing, gravure printing, gravure offset printing, etc. can be applied, and known screen printing is preferable.
In the screen printing method, using the above-mentioned ink, the polishing layer 1
5, the outer peripheral portion 21, the inner peripheral portion 23, and the groove portion 4 which are not formed
It is sufficient to form the pattern shape so that it does not overlap with the polishing layer 15 at least on the outer peripheral portion 21 of 1. Usually, in the process of manufacturing the polishing sheet 10, the polishing layer 15 is formed after the water-repellent layer 32 is formed.

Usually, after forming the water-repellent layer 32, the water-repellent layer 32 and the polishing layer 15 are formed in order to form the polishing layer 15.
It is necessary to match the registration (positional relationship) and print. The registration is performed by coloring the water-repellent layer 32 in the same manner as in normal printing, separately providing registration marks (called register marks) for registration, or through holes at specific positions. Open and position with a pin or the like.

FIG. 13 is a schematic sectional view of a polishing sheet showing one embodiment of claim 11. Depending on the type of the material to be polished, the purpose of polishing, and the polishing method, dry polishing may be performed without dropping a lubricant such as water between the material to be polished and the polishing sheet. In this case, it is general that the amount of polishing debris and lost abrasive particles generated during the polishing operation increases. In addition, the polishing dust and the fallen abrasive particles may scatter, which may cause scratches on the material to be polished or pollute the atmospheric environment. Here, in addition to supplementing and discharging polishing debris and lost abrasive particles due to the provision of the groove structure, by providing the adhesive layer 33 in the recess of the groove, the adhesive of the adhesive layer 33 removes the abrasive debris and the lost abrasive particles. Achieves stable polishing work with very few scratches by positively supplementing.

As the pressure-sensitive adhesive of the pressure-sensitive adhesive layer 33, a known pressure-sensitive adhesive that adheres with pressure can be applied. The pressure-sensitive adhesive is not particularly limited, and examples thereof include natural rubber-based, synthetic rubber-based resins such as butyl rubber / polyisoprene / polyisobutylene / polychloroprene / styrene-butadiene copolymer resin, silicone-based resins, acrylic-based resins. , Polyvinyl acetate / ethylene-vinyl acetate copolymer, vinyl acetate resin, urethane resin, acrylonitrile, hydrocarbon resin, alkylphenol resin, rosin
Rosin resins such as rosin triglyceride and hydrogenated rosin can be applied.

A latex, an aqueous dispersion, or an organic solvent solution of these resins or their mixtures may be printed by aligning them with the groove shape by a known printing method such as screen printing and then drying. . The adhesive layer 33 may be formed on a part of the recess instead of the entire surface, and the thickness of the adhesive may be smaller than that of the polishing layer. The adhesive force and cohesive force of the pressure-sensitive adhesive can be appropriately selected according to the material to be polished and the polishing conditions. However, in order to supplement the polishing dust and the dropped abrasive particles, the higher the value, the better.

FIG. 14 is a schematic sectional view of a polishing sheet showing an embodiment of claim 12. FIG. 15 shows the claim 1.
It is a typical sectional view of a polishing sheet showing one example of No. 2 of the drawings. FIG. 14 shows an elastic layer 63 in which the polishing layer 15 is not formed.
The back surface adhesive layer 71 is provided on the surface, and FIG.
1 and a release paper 73 are provided. Both of them are back surface adhesive layers 71 and can be easily attached to and removed from the polishing pad attachment portion of the polishing machine. Even if not a skilled worker, the replacement work of the worn polishing sheet can be reliably performed in a short time, and the operation efficiency of the polishing machine can be improved.

As the adhesive for the back surface adhesive layer 71, the same adhesive as that used for the polishing layer surface can be applied. The pressure-sensitive adhesive is not particularly limited, and examples thereof include natural rubber-based, synthetic rubber-based resins such as butyl rubber / polyisoprene / polyisobutylene / polychloroprene / styrene-butadiene copolymer resin, silicone-based resins, acrylic-based resins. , Vinyl acetate resin such as polyvinyl acetate / ethylene-vinyl acetate copolymer, urethane resin,
Rosin resins such as acrylonitrile, hydrocarbon resin, alkylphenol resin, rosin / rosin triglyceride / hydrogenated rosin can be applied.

A latex, an aqueous dispersion, or an organic solvent solution of these resins or their mixtures is applied to the elastic layer 63 surface by a known coating such as roll coating, bar coating, comma coating, or screen printing, and a printing method. , Print and dry. The thickness of the back adhesive layer 71. 5 to 50 μm, preferably 10 to
It is 30 μm. 14 is a polishing sheet having the polishing layer 15 on the entire surface of claim 1 shown in FIG. 1, and FIG. 15 is an arbitrary patterned polishing layer 15 of claim 8 shown in FIG.
It is a polishing sheet having. Normally, as shown in FIG. 15, a release paper 73 is provided on the back surface adhesive layer 71 so as not to stick when a polishing sheet is piled up or rolled up. However, as shown in FIG. 14, polishing of the polishing layer 15 is performed. If the agent works to prevent sticking, the release paper 73 is unnecessary. The release paper 73 may be a known release paper, such as high-quality paper or polyethylene terephthalate coated with a silicone resin.

When the polishing sheet 10 of the present invention is used, for example, when the material to be polished is a semiconductor and flattening is performed,
In order for the polishing sheet 10 to follow the waviness and warpage that occur in the entire material to be polished, it is necessary to have appropriate elasticity (compressibility and bending elasticity), and fine irregularities existing on the processed surface of the material to be polished. In order to flatten the portion, the polishing layer surface needs to have an appropriate hardness (Young's modulus). In the polishing sheet 10 of the present invention according to claim 5, the elastic layer 63 and / or the adhesive layer 61 are made of different materials and thicknesses depending on the type of the material to be flattened, such as elasticity (compressibility and bending elasticity) and hardness. (Young's modulus)
Can be adjusted. That is, the base film 11,
By combining the material and the thickness of the elastic layer 63 and / or the adhesive layer 61, it is possible to deal with various materials to be polished.

The polishing sheet 10 of the present invention according to claim 6 is also provided.
Is the base film 11, the elastic layer 63 and the adhesive layer 61.
By combining the Young's modulus of the above, it is possible to deal with various kinds of materials to be polished. In particular, the elastic layer 63 and the adhesive layer 6
By setting the Young's modulus of 1 to be smaller than that of the base film 11, the elastic layer 63 and the adhesive layer 61 function as a cushion layer (pad function in normal CMP polishing).

The polishing sheet 10 of the present invention according to claim 7 is also provided.
By setting the Young's modulus of the adhesive layer 61 to be smaller than the Young's modulus of the base film 11 and the elastic layer 63, the intermediate adhesive layer 61 serves as a cushion layer. Therefore, the surface of the polishing layer 15 can be bent in a concave shape without wrinkles and the like, and the material to be polished, for example, the convex shape required for polishing the end face of an optical fiber, can be polished. Claim 5
The details of the present invention of claims 7 to 7 will be described in Examples.

[0055]

Example 1 As a base film, a Melinex 54 having a thickness of 75 μm and having a primer layer applied in advance.
2 (manufactured by Teijin DuPont, polyethylene terephthalate film trade name) was used to apply SRX to the primer layer surface.
An outer peripheral portion 21 and an inner peripheral portion 23 each having a donut-shaped polishing layer of FIG. 3 having a coating liquid of 211 (trade name of Toray Dow Corning Silicone, silicone resin trade name) dissolved in toluene are not formed. With a plate cylinder with a pattern of
A water-repellent layer 32 was obtained by gravure printing and drying so that the thickness after drying was 1 μm. Next, the average particle diameter of the diamond powder is 35.0% by weight and the amount of Byron 2 is 2 μm so that the surface of the water-repellent layer 32 is aligned and not overlapped with the water-repellent layer 32.
00 (Toyobo Co., Ltd., polyester resin) 23.0% by weight, silica 2.0% by weight, methyl ethyl ketone 20.0
A doughnut-shaped polishing layer pattern as shown in FIG. 3 was made using a composition liquid for forming a polishing layer consisting of 20% by weight of toluene and 20% by weight of toluene.
It is silk-screen printed and dried so that the length becomes m. After the drying, it was further heated and cured at 150 ° C. for 20 minutes. Next, urethane-based two-component curing adhesive A as an adhesive
-310 and curing agent A-5 (both manufactured by Takeda Pharmaceutical Company,
(Trade name) was used to laminate with polyethylene non-woven fabric Tyvek (manufactured by DuPont, trade name) by a dry lamination method. A polishing sheet having a donut-shaped polishing layer pattern of Example 1 was obtained by punching out a circle having a diameter of 200 mmφ.

(Example 3) As a base film, a Melinex 5 having a thickness of 75 μm and having a primer layer applied in advance.
42 (manufactured by Teijin DuPont, polyethylene terephthalate film trade name) was used, on the surface of the primer layer, an average particle diameter of 1 μm diamond powder 35.0% by weight, Byron 200 (Toyobo Co., Ltd., polyester resin) 23.0% by weight, Using a polishing layer forming composition liquid consisting of 2.0% by weight of colloidal silica, 20.0% by weight of methyl ethyl ketone and 20% by weight of toluene, a groove width as shown in FIG.
mm, and a doughnut-shaped polishing layer pattern having a plurality of concentric circular grooves having a groove interval of 2 mm. The silkscreen printing plate is silkscreen-printed and dried so that the thickness after drying is 8 μm. After the drying, further at 150 ° C., 2
It was cured by heating for 0 minutes. Then, an anchor coating agent consisting of 5 parts by weight of polyethyleneimine and 95 parts by weight of a mixed solvent of water / methyl alcohol = 1/1 was roll-coated on the 11th surface of the base film to a thickness of 0.1 μm (after drying). The low density polyethylene is melted by an extruder and then flowed down in a curtain shape having a thickness of 20 μm to form a laminated body of polyethylene foam having a thickness of 100 μm and polyethylene terephthalate having a thickness of 75 μm. The surfaces were bonded together by a melt extrusion lamination method (so-called polysand method because those skilled in the art simultaneously form a polyethylene layer and stack other materials). Next, the groove portion 4 of the polishing layer 15 previously formed
1. A coating solution consisting of 30 parts by weight of an acrylic resin adhesive and 70 parts by weight of a mixed solvent of methyl ethyl ketone / toluene = 1/1 was applied to the outer periphery of the polishing layer having concentric grooves in FIG. Portion 21, inner peripheral portion 23 and groove portion 41
A silk plate with a pattern of 5 μm after drying
Then, silk-screen printing was performed so that the adhesive layer 33 was obtained. Next, to a PET sepa paper having a thickness of 50 μm, 30 parts by weight of an acrylic resin pressure-sensitive adhesive of methyl ethyl ketone /
A coating liquid consisting of 70 parts by weight of a toluene = 1/1 mixed solvent,
The polyethylene terephthalate surface of the laminate of the foamed polyethylene and polyethylene terephthalate, which had been previously laminated, was overlaid on the back surface adhesive layer 71 obtained by bar coating and drying so that the thickness after drying was 20 μm. I matched it. A polishing sheet having a donut-shaped polishing layer pattern having concentric circular grooves and having an adhesive layer on the back surface was obtained by punching out a circle having a diameter of 200 mmφ.

Example 2 A polishing sheet of Example 2 was prepared in the same manner as in Example 1 except that the materials and thicknesses of the base film, the adhesive layer and the elastic layer were as shown in Table 1.

Example 4 A polishing sheet of Example 4 was prepared in the same manner as in Example 3 except that the materials and thicknesses of the base film, the adhesive layer and the elastic layer were as shown in Table 1.

[0059]

[Table 1]

(Comparative Example 1 and Comparative Example 2) Comparative Example 1 to Comparative Example were carried out in the same manner as in Example 1 except that the material and thickness of the base film, the adhesive layer and the elastic layer were as shown in Table 1. This was No. 2 polishing sheet.

(Evaluation) Evaluation was carried out on the polishing sheets of Examples and Comparative Examples after the materials to be polished were test-polished as follows.
The lubricant was distributed on the polishing sheet, and the scratches on the polishing surface of the material to be polished were used. Zirconia, quartz,
In order to make the pieces to be test-polished the same, aluminum pieces were preliminarily polished with a diamond film corresponding to # 400. Next, a 200 mmφ polishing sheet of Examples and Comparative Examples was fixed to the polishing platen using a Laball-5 polishing machine manufactured by Strual Co., Ltd. as a testing machine, and 10 ml of pure water as a lubricant was dropped onto the center of the polishing sheet and rotated. Rotate at a speed of 150 rpm to bring it into contact with the material to be polished 60
Polished for seconds. The evaluation was carried out based on the distribution state of the lubricant and the scratches and the state of the polishing surface. The distribution state of the lubricant was visually observed after the polishing test, and the scratches and the state of the polishing surface were observed with an optical microscope of 800 times. The results are shown in Table 2.

[0062]

[Table 2]

As shown in the results of Table 2, in Examples 1 to 4, the lubricant was applied to the predetermined polishing layer or the entire polishing layer.
It is uniformly spread and distributed, and the polishing state is zirconia.
All quartz / aluminum sections were good. Comparative Example 1
In Comparative Example 2, the lubricant was evenly spread and distributed on the predetermined polishing layer or the entire surface of the polishing layer, but in the polished state, there were deep scratches on the zirconia-aluminum slices, and even on the quartz slices. Yes, it was a failure.

[0064]

As described above, according to the present invention of claim 1 to claim 7, an elastic layer having a polishing layer on one surface of the base film and a pad function on the other surface. By using the provided polishing sheet 10, the base film 11,
By selecting the material and thickness of the elastic layer 63 and / or the adhesive layer 61, the degree of elasticity can be adjusted, and a polishing sheet suitable for the material to be polished can be obtained. In addition, as the material, many known and existing materials can be used. Further, in the production of the polishing sheet 10, the elastic layer can be easily integrated via the adhesive layer, the existing equipment can be used by the known lamination method, and the inexpensive and stable polishing sheet can be supplied. .

The sheet of the present invention according to claim 8 has a polishing layer 15
Is formed into an arbitrary pattern that is required when using polishing,
By providing a groove in the patterned polishing layer 15, expensive polishing particles can be significantly reduced. For example, 150 of the embodiment
Taking the polishing sheet for the final polishing of the optical connector of mmφ as an example, if the entire solid polishing layer has a donut shape, the material cost can be reduced by 26% or more only by the area ratio. Creation of composition liquid,
Considering changes in the coating method and process losses will contribute to further reduction.

Further, in claim 9, even if the grooves 41, 43, 45, 47, 49, 51 are formed in the doughnut-shaped polishing layer 15, the polishing layer area necessary for the polishing work is covered. The polishing accuracy and the polishing work do not have any problems. In addition, polishing debris and fallen polishing particles during polishing work are stored in the groove, and the surface of the polishing material does not damage the surface of the polishing material. Therefore, the polishing time is shortened.

Further, since the formation of the polishing layer 15 can be changed from the conventional coating method to the silk screen printing, it is not necessary to use a high-performance and large-sized coating machine. When the polishing layer 15 is formed by silk screen printing,
On the surface of the polishing layer 15, a so-called screen pattern, which is peculiar to silk screen printing, appears on the surface of the polishing layer 15 to form a mesh-like ridge surface. This fine mesh-like ridged surface is formed. It is considered that the ridge surface enhances the force for grinding the material to be polished. Although the reason is not clear, it is presumed that the ridges are due to the edge effect of the polishing layer, the retention of an appropriate amount of the lubricating liquid, the embedding of polishing debris, and the like.

Further, the mesh-like ridge surface has a fine surface irregularity shape, and a liquid lubricant such as water is evenly distributed. Moreover, in the case of the grooved polishing layer of the present invention, the polishing scraps and the lost abrasive particles generated during the polishing operation are complementarily stored in the groove, or, depending on the shape of the groove, they can be discharged to the outside. The surface of the polishing material that has already been polished is not damaged, the surface of the fresh polishing sheet always comes into contact with the material to be polished, and the mutual movement keeps the polishing accuracy, and the polishing accuracy is maintained and stable polishing can be performed. Is also shortened.

Diamond, alumina, iron oxide, carborundum, chromium oxide, and cerium oxide are particularly suitable as abrasives for polishing glass materials such as lenses, optical disks, and optical fibers. Suitable and excellent in polishing and grinding ability.

According to the present invention of claim 10, the water repellent layer 32.
Does not hold a lubricant such as water dropped during polishing, and reliably repels it and supplies it only to the surface of the polishing layer 15. Although the lubricant is usually dropped to the central portion, it does not accumulate in the central portion of the polishing sheet as it is and stay there, or leak to the outer peripheral portion of the polishing sheet due to rotation and become insufficient. The amount of lubricant is not large or small, and the required amount spreads evenly and effectively, enabling stable polishing.

According to the eleventh aspect of the present invention, even in the case of dry polishing, the polishing debris and fallen abrasive particles generated during the polishing work, and the adhesive of the adhesive layer 33 in the groove recess positively removes the polishing debris and fallen abrasive particles. Supplementally, the scratches on the material to be polished are extremely small, and stable polishing work can be performed.

According to the twelfth aspect of the present invention, by providing the back surface adhesive layer 71 on the back surface of the polishing sheet, it can be easily attached to and removed from the polishing pad attachment portion of the polishing machine. Even if not a skilled worker, the replacement work of the worn polishing sheet can be reliably performed in a short time, and the operation efficiency of the polishing machine can be improved.

[Brief description of drawings]

FIG. 1 is a schematic plan view of a polishing sheet showing one embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a schematic plan view of a polishing sheet showing an embodiment of the present invention according to claim 8.

4 is a sectional view taken along line BB of FIG.

FIG. 5 is a schematic plan view of a polishing sheet showing an embodiment of the present invention according to claim 9.

FIG. 6 is a sectional view taken along line CC of FIG.

FIG. 7 is a plan view showing an embodiment of the present invention according to claim 9;

FIG. 8 is a plan view showing an embodiment of the present invention according to claim 9.

FIG. 9 is a plan view showing an embodiment of the present invention according to claim 9;

FIG. 10 is a plan view showing an embodiment of the present invention according to claim 9.

FIG. 11 is a plan view showing an embodiment of the present invention according to claim 9;

FIG. 12 is a schematic cross-sectional view of a polishing sheet showing an embodiment of claim 10.

FIG. 13 is a schematic sectional view of a polishing sheet showing one embodiment of claim 11.

FIG. 14 is a schematic cross-sectional view of a polishing sheet showing an embodiment of claim 12;

FIG. 15 is a schematic cross-sectional view of a polishing sheet showing an embodiment of claim 12;

[Explanation of symbols]

10 Polishing sheet 11 Base film 13 Primer layer 15 Polishing layer 17 binder 19 Abrasive particles 21 Outer periphery 23 Inner circumference 32 Water repellent layer 33 Adhesive layer 41, 43, 45, 47, 49, 51 Groove 61 Adhesive layer 63 Elastic layer 71 Back adhesive layer 73 Release Paper

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Runa Nakamura             1-1-1, Ichigaya-Kagacho, Shinjuku-ku, Tokyo             Dai Nippon Printing Co., Ltd. (72) Inventor Hideki Izawa             1-1-1, Ichigaya-Kagacho, Shinjuku-ku, Tokyo             Dai Nippon Printing Co., Ltd. F term (reference) 3C063 AA03 AB07 BA24 BC03 BF02                       BG01 BG08 BG22 BH07

Claims (12)

[Claims] 1. A polishing sheet having a polishing film on one surface of a base film and an elastic layer on the other surface, wherein the elastic layer is integrally provided via an adhesive layer. A polishing sheet having an elastic layer. 2. The polishing sheet having an elastic layer according to claim 1, wherein the elastic layer comprises a single layer of an organic polymer, a foam, a non-woven fabric, or a paper, or a laminate thereof. 3. An adhesive that is cured by heat, ultraviolet rays, or ionizing radiation is used as the adhesive layer, and the elastic layer is formed by a dry lamination method or a non-sol lamination method.
An abrasive sheet having an elastic layer according to claim 1 or 2, which is provided integrally with a substrate film. 4. A polyolefin resin as the adhesive layer,
A polyolefin-based copolymer resin, a copolymer resin of an olefin and another monomer, an ionomer, or a thermoplastic elastomer alone, or a mixture of a plurality thereof, and a laminate of a plurality thereof, and the adhesive layer is extruded and laminated. A polishing sheet having an elastic layer according to claim 1 or 2, wherein the polishing sheet is integrally provided on a base film by a method. 5. The elastic layer according to claim 1, wherein the elasticity and / or thickness of the elastic layer and / or the adhesive layer adjusts the elasticity of the polishing sheet suitable for polishing the material to be polished. Having a polishing sheet. 6. The Young's modulus of the base film is higher than the Young's modulus of the elastic layer and / or the adhesive layer, and the hardness of the polishing sheet suitable for polishing the material to be polished is adjusted by the material and thickness of the base film. A polishing sheet having the elastic layer according to any one of claims 1 to 4. 7. The Young's modulus of the adhesive layer is smaller than the Young's modulus of the base film and the elastic layer, and the elasticity and hardness of the polishing sheet suitable for polishing the material to be polished are adjusted by the material and thickness of the base film. A polishing sheet having the elastic layer according to any one of claims 1 to 4. 8. The polishing sheet having an elastic layer according to claim 1, wherein the polishing layer is formed in an arbitrary pattern required when used for polishing. 9. The polishing sheet having an elastic layer according to claim 8, wherein a partial recess is formed in the polishing layer. 10. The water-repellent layer is provided on a portion where the polishing layer is not formed.
A polishing sheet having the elastic layer described. 11. The adhesive layer is provided on a portion where the polishing layer is not formed, according to any one of claims 8 to 9.
A polishing sheet having the elastic layer described. 12. A polishing sheet having an elastic layer according to claim 1, wherein an adhesive layer is provided on the surface of the elastic layer.