Double-sided adhesive tape for bonding and fixing polishing pad and preparation method of double-sided adhesive tape

Abstract

The invention discloses a double-sided adhesive tape for bonding and fixing a polishing pad and a preparation method of the double-sided adhesive tape. The double-sided adhesive tape comprises a first release layer, a first pressure-sensitive adhesive layer, a base material layer, a second pressure-sensitive adhesive layer and a second release layer which are sequentially stacked, the first pressure-sensitive adhesive layer is obtained by coating a first adhesive pre-coating liquid and then curing, and the first adhesive pre-coating liquid is prepared from the following raw materials in parts by weight: 100 parts of an acrylate polymer, 15-30 parts of tackifying resin and 0.25-1.5 parts of a curing agent. Through the unique acrylate polymer molecular structure, differential formula and adhesive tape structure design, the double-sided adhesive tape capable of being well used for bonding and fixing the polishing pad is obtained, the high-viscosity surface is suitable for polishing pads with different hardness degrees, the low-viscosity surface is suitable for base materials with different polarities, and meanwhile, the double-sided adhesive tape has the advantages of being easy to remove, convenient to use and the like with a polishing base. And due to the characteristic of no adhesive residue, an effective guarantee is provided for a chemical mechanical polishing process, and the production efficiency and the yield of products are greatly improved.

Description

Technical Field

[0001] The invention relates to the field of adhesive materials for polishing pads, and in particular to a double-sided adhesive tape for bonding and fixing a polishing pad and a preparation method thereof. Background Art

[0002] CMP, or chemical mechanical polishing, is a technology that uses a combination of chemical and mechanical methods to finely grind and polish the surface of silicon wafers. It is a key process in semiconductor manufacturing.

[0003] The auxiliary materials involved in the CMP process include: polishing pads, polishing bases, polishing liquids, etc. Common materials for polishing machines include SiC, PTFE, etc., and the polarity of the materials varies greatly; polishing pads currently have two types: hard pads and soft pads. Generally, hard pads are used for rough polishing of the wafer, and then soft pads are used for fine polishing to achieve wafer flatness. The surface of the polishing pad is generally designed to have a regular concave-convex structure to achieve the purpose of polishing. The presence of the concave-convex structure can easily lead to problems such as uneven fit and residual gaps when the polishing pad is fitted to the polishing base, thereby affecting the overall polishing quality and even the risk of equipment damage. In addition, there are particularly strict requirements for the use time of the polishing pad, and it needs to be replaced regularly, otherwise it will also cause product quality problems.

[0004] Therefore, the adhesive tape between the polishing base and the polishing pad has higher performance requirements, taking into account the bonding of high and low surface energy materials, efficient lamination and degassing, excellent temperature resistance and water resistance. At the same time, the entire polishing process needs to maintain high adhesion and shear resistance. Finally, it needs to be easy to remove without residual glue.

[0005] Patent No. CN114921204A prepared a rubber-type pressure-sensitive adhesive tape, the substrate is a polyester film, and the two sides are designed with differentiated peeling force. The defects of this design are: the polarity of the rubber-type pressure-sensitive adhesive itself is low, and the substrate is a high-polarity polyester material. The polarity difference between the pressure-sensitive adhesive and the substrate is very large, so there is a risk of delamination between the adhesive layer and the substrate layer. At the same time, it does not have air exhaust performance, and it is easy to produce bubble points when it is attached to the polishing base, affecting the quality of the overall product.

[0006] Patent No. CN104169384B prepares an acrylic pressure-sensitive adhesive tape, but does not clearly describe the overall tape structure, and may not reflect an excellent exhaust solution.

[0007] Therefore, it is necessary to improve the existing technology to provide a more reliable solution. Summary of the invention

[0008] The technical problem to be solved by the present invention is to provide a double-sided adhesive tape for bonding and fixing a polishing pad and a preparation method thereof in view of the deficiencies in the above-mentioned prior art.

[0009] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: In a first aspect of the present invention, a double-sided adhesive tape for bonding and fixing a polishing pad is provided, comprising a first release layer, a first pressure-sensitive adhesive layer, a substrate layer, a second pressure-sensitive adhesive layer and a second release layer which are sequentially stacked;

[0010] The first pressure-sensitive adhesive layer is obtained by coating a first adhesive pre-coating liquid and then curing it. The raw materials for preparing the first adhesive pre-coating liquid include the following components in parts by weight: 100 parts of acrylate polymer, 15-30 parts of tackifying resin, and 0.25-1.5 parts of curing agent.

[0011] Preferably, the acrylic ester polymer is prepared from acrylic soft monomers, acrylic hard monomers and acrylic functional monomers by solution polymerization, and the DSC glass transition temperature of the acrylic ester polymer is -30 to -50°C, the weight average molecular weight is 450,000-600,000, and the molecular weight distribution is 5-15.

[0012] Preferably, the acrylic acid ester polymer is prepared by the following method:

[0013] 1) By weight, 40-60 parts of butyl acrylate, 30-50 parts of isooctyl acrylate, 1-4 parts of β-carboxyethyl acrylate, 1.5-6 parts of acrylic acid, 0.15-0.6 parts of 2-hydroxyethyl acrylate, and 2.5-9 parts of vinyl acetate are mixed uniformly to obtain a mixed monomer, which is divided into a first part of monomers and a second part of monomers in a mass ratio of 3:2;

[0014] 2) The first part of the monomers is put into a reactor, and toluene accounting for 20% of the total mass of the first part of the monomers and ethyl acetate equal to the toluene are added, and the mixture is heated to 65-70° C. with nitrogen, and azobisisobutyl cyanide accounting for 0.1% of the total mass of the first part of the monomers is added, and the reaction is carried out for 1-3 hours. The temperature is raised to 75° C.-80° C. and the remaining second part of the monomers are added dropwise, and the mixture is finished after 1-3 hours; then the reaction is continued for 15-60 minutes, and azobisisobutyl cyanide accounting for 0.2% of the total mass of the mixed monomers is added, and the reaction is continued at 78-82° C. for 1-4 hours, and the temperature is lowered and the material is discharged to obtain an acrylate polymer.

[0015] Preferably, the acrylic acid ester polymer is prepared by the following method:

[0016] 1) By weight, 50 parts of butyl acrylate, 40 parts of isooctyl acrylate, 2 parts of β-carboxyethyl acrylate, 3 parts of acrylic acid, 0.3 parts of 2-hydroxyethyl acrylate, and 4.7 parts of vinyl acetate were uniformly mixed to obtain a mixed monomer, which was divided into a first part of monomers and a second part of monomers in a mass ratio of 3:2;

[0017] 2) The first part of the monomers is put into a reactor, and toluene accounting for 20% of the total mass of the first part of the monomers and ethyl acetate equal to the mass of the toluene are added, and the mixture is heated to 68° C. with nitrogen, and azobisisobutyl cyanide accounting for 0.1% of the total mass of the first part of the monomers is added, and the reaction is carried out for 1.5 hours. The temperature is raised to 78° C. and the remaining second part of the monomers are added dropwise, and the mixture is added dropwise after 1.5 hours; then the reaction is continued for 0.5 hours, and azobisisobutyl cyanide accounting for 0.2% of the total mass of the mixed monomers is added, and the reaction is continued at 78° C. for 2 hours. The temperature is lowered to below 45° C. and the material is discharged to obtain an acrylate polymer.

[0018] Preferably, the second pressure-sensitive adhesive layer is obtained by coating a second adhesive pre-coating liquid and then curing it, and the raw materials for preparing the second adhesive pre-coating liquid include the following components in parts by weight: 100 parts of acrylate polymer and 0.3-1.5 parts of curing agent.

[0019] Preferably, the first release layer is a planar release layer, and the second release layer is a grid release layer, and the grid shape is any one of a square or a rhombus;

[0020] The mesh shape size of the mesh release layer is 550*550μm to 2000*2000μm.

[0021] Preferably, the substrate layer is a polyester film, the surface tension of both sides of the film is greater than 44 dynes, and the thickness is 12 to 50 μm.

[0022] Preferably, the tackifying resin is a mixture of a high softening point tackifying resin and a low softening point tackifying resin, the high softening point tackifying resin has a softening point of 100-150°C; the low softening point tackifying resin has a softening point of 70-100°C;

[0023] The high softening point tackifying resin is at least one of terpene phenolic resin, rosin resin and modified rosin resin, and the low softening point tackifying resin is at least one of rosin resin and rosin modified resin.

[0024] Preferably, the curing agent is at least one of an isocyanate curing agent or an epoxy curing agent.

[0025] A second aspect of the present invention provides a method for preparing the double-sided adhesive tape for bonding and fixing the polishing pad as described above, comprising the following steps:

[0026] S1. Mix 100 parts of acrylate polymer and 15-30 parts of tackifying resin by weight and stir for 20-30 minutes, then add 0.25-1.5 parts of curing agent and stir for 20-30 minutes to obtain a first adhesive pre-coating liquid;

[0027] S2, evenly coating the first adhesive pre-coating liquid on the release surface of the first release layer, drying and curing at 60-110° C. to form a first pressure-sensitive adhesive layer, and laminating the adhesive surface on the surface of the substrate layer to obtain a semi-finished product;

[0028] S3, mixing 100 parts of acrylate polymer and 0.3-1.5 parts of curing agent by weight and stirring for 20-30 minutes to obtain a second adhesive pre-coating liquid;

[0029] S4, evenly coating the second adhesive pre-coating liquid on the bottom surface of the substrate layer, drying and curing at 60-110° C. to form a second pressure-sensitive adhesive layer, attaching a second release layer to the adhesive surface, winding up, and ripening to obtain the double-sided adhesive tape for bonding and fixing the polishing pad.

[0030] The beneficial effects of the present invention are:

[0031] The present invention obtains a double-sided tape that can be well used for bonding and fixing polishing pads through a unique acrylic polymer molecular structure design, a differentiated formula design, and a tape structure design. The high-viscosity surface (first pressure-sensitive adhesive layer) is suitable for polishing pads of different hardness and softness, and the low-viscosity surface (second pressure-sensitive adhesive layer) can be suitable for base materials of different polarities. At the same time, it has the characteristics of easy removal and no residual adhesive on the polishing base, providing effective protection for the chemical mechanical polishing process, greatly improving the production efficiency and yield of the product. The double-sided tape of the present invention has efficient lamination and exhaust, excellent temperature resistance and water resistance, and maintains high adhesion, shear resistance, easy removal, and no residual adhesive during the entire polishing process. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below in conjunction with embodiments so that those skilled in the art can implement the invention with reference to the description.

[0033] It should be understood that terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0034] The test methods used in the following examples are conventional methods unless otherwise specified. The materials and reagents used in the following examples are all commercially available unless otherwise specified. In the following examples, if no specific conditions are specified, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used, if the manufacturer is not specified, are all conventional products that can be purchased commercially.

[0035] The present invention provides a double-sided adhesive tape for bonding and fixing a polishing pad, comprising a first release layer, a first pressure-sensitive adhesive layer, a substrate layer, a second pressure-sensitive adhesive layer and a second release layer which are sequentially stacked;

[0036] In a preferred embodiment, the first release layer is a planar release layer, which provides adhesive surface protection for the first pressure-sensitive adhesive layer; the second release layer is a grid release layer, which provides adhesive surface protection for the second pressure-sensitive adhesive layer and simultaneously promotes the formation of regular and continuous exhaust grooves on the adhesive surface of the second pressure-sensitive adhesive layer; the peeling force between the first release layer and the first pressure-sensitive adhesive layer is less than the peeling force between the second pressure-sensitive adhesive layer and the second release layer, thereby avoiding the reverse release phenomenon during use;

[0037] More preferably, the grid shape is any one of square or rhombus; the grid shape size of the grid release layer is 550*550μm to 2000*2000μm. The line width for forming the air vent of the adhesive layer is 130-300μm, and the line height is 9-50μm.

[0038] The first pressure-sensitive adhesive layer is used to bond with the non-polishing surface of the polishing pad, and the second pressure-sensitive adhesive layer is used to bond the polishing pad with the polishing base. The adhesive tape prepared by the present invention has high-efficiency lamination and air-exhaust properties, excellent temperature resistance and water resistance, and at the same time maintains high adhesion, shear resistance, easy removal, and no residual adhesive during the entire polishing process.

[0039] In a preferred embodiment, the substrate layer is a polyester film, the surface tension of both sides of the film is greater than 44 dynes, and the thickness is 12 to 50 μm.

[0040] In a preferred embodiment, the first pressure-sensitive adhesive layer is obtained by coating a first adhesive pre-coating liquid and then curing it, and the raw materials for preparing the first adhesive pre-coating liquid include the following components in parts by weight: 100 parts of acrylate polymer, 15-30 parts of tackifying resin, and 0.25-1.5 parts of curing agent. In a more preferred embodiment, the peeling force of the first pressure-sensitive adhesive layer is 18N to 25N / 25mm.

[0041] In a preferred embodiment, the acrylic ester polymer is prepared by solution polymerization of acrylic soft monomers, acrylic hard monomers and acrylic functional monomers, and the DSC glass transition temperature of the acrylic ester polymer is -30 to -50°C, the weight average molecular weight is 450,000-600,000, and the molecular weight distribution is 5-15.

[0042] In a preferred embodiment, the acrylate polymer is prepared by the following method:

[0043] 1) By weight, 40-60 parts of butyl acrylate, 30-50 parts of isooctyl acrylate, 1-4 parts of β-carboxyethyl acrylate, 1.5-6 parts of acrylic acid, 0.15-0.6 parts of 2-hydroxyethyl acrylate, and 2.5-9 parts of vinyl acetate are mixed uniformly to obtain a mixed monomer, which is divided into a first part of monomers and a second part of monomers in a mass ratio of 3:2;

[0044] 2) The first part of the monomers is put into a reactor, and toluene accounting for 20% of the total mass of the first part of the monomers and ethyl acetate equal to the toluene are added, and the mixture is heated to 65-70° C. with nitrogen, and azobisisobutyl cyanide accounting for 0.1% of the total mass of the first part of the monomers is added, and the reaction is carried out for 1-3 hours. The temperature is raised to 75° C.-80° C. and the remaining second part of the monomers are added dropwise, and the mixture is finished after 1-3 hours; then the reaction is continued for 15-60 minutes, and azobisisobutyl cyanide accounting for 0.2% of the total mass of the mixed monomers is added, and the reaction is continued at 78-82° C. for 1-4 hours, and the temperature is lowered and the material is discharged to obtain an acrylate polymer.

[0045] In a more preferred embodiment, the acrylate polymer is prepared by the following method:

[0046] 1) By weight, 50 parts of butyl acrylate, 40 parts of isooctyl acrylate, 2 parts of β-carboxyethyl acrylate, 3 parts of acrylic acid, 0.3 parts of 2-hydroxyethyl acrylate, and 4.7 parts of vinyl acetate were uniformly mixed to obtain a mixed monomer, which was divided into a first part of monomers and a second part of monomers in a mass ratio of 3:2;

[0047] 2) The first part of the monomers is put into a reactor, and toluene accounting for 20% of the total mass of the first part of the monomers and ethyl acetate equal to the mass of the toluene are added, and the mixture is heated to 68° C. with nitrogen, and azobisisobutyl cyanide accounting for 0.1% of the total mass of the first part of the monomers is added, and the reaction is carried out for 1.5 hours. The temperature is raised to 78° C. and the remaining second part of the monomers are added dropwise, and the mixture is added dropwise after 1.5 hours; then the reaction is continued for 0.5 hours, and azobisisobutyl cyanide accounting for 0.2% of the total mass of the mixed monomers is added, and the reaction is continued at 78° C. for 2 hours. The temperature is lowered to below 45° C. and the material is discharged to obtain an acrylate polymer.

[0048] In a preferred embodiment, the second pressure-sensitive adhesive layer is obtained by coating a second adhesive pre-coating liquid and then curing it, and the raw materials for preparing the second adhesive pre-coating liquid include the following components by weight: 100 parts of acrylate polymer and 0.3-1.5 parts of curing agent. In a more preferred embodiment, the thickness of the second pressure-sensitive adhesive layer is 30-40 μm, the peeling force is 6N-15N / 25mm, and the initial effective use area of ​​the adhesive layer is more than 60%.

[0049] In a preferred embodiment, the tackifying resin is a mixture of a high softening point tackifying resin and a low softening point tackifying resin, wherein the high softening point tackifying resin has a softening point of 100-150°C; and the low softening point tackifying resin has a softening point of 70-100°C.

[0050] In a more preferred embodiment, the high softening point tackifying resin is at least one of terpene phenolic resin, rosin resin, and modified rosin resin, and the low softening point tackifying resin is at least one of rosin resin and rosin modified resin.

[0051] In a preferred embodiment, the curing agent is at least one of an isocyanate curing agent or an epoxy curing agent.

[0052] The present invention also provides a method for preparing the double-sided adhesive tape for bonding and fixing the polishing pad as described above, comprising the following steps:

[0053] S1. Mix 100 parts of acrylate polymer and 15-30 parts of tackifying resin by weight and stir for 20-30 minutes, then add 0.25-1.5 parts of curing agent and stir for 20-30 minutes to obtain a first adhesive pre-coating liquid;

[0054] S2, evenly coating the first adhesive pre-coating liquid on the release surface of the first release layer, drying and curing at 60-110° C. to form a first pressure-sensitive adhesive layer, and laminating the adhesive surface on the surface of the substrate layer to obtain a semi-finished product;

[0055] S3, mixing 100 parts of acrylate polymer and 0.3-1.5 parts of curing agent by weight and stirring for 20-30 minutes to obtain a second adhesive pre-coating liquid;

[0056] S4, evenly coating the second adhesive pre-coating liquid on the bottom surface of the substrate layer, drying and curing at 60-110° C. to form a second pressure-sensitive adhesive layer, attaching a second release layer to the adhesive surface, winding up, and ripening to obtain the double-sided adhesive tape for bonding and fixing the polishing pad.

[0057] In a preferred embodiment, in step S2 and step S4, 8 continuous ovens (each oven is 4M) are used for drying and curing, and the temperature settings are: 60°C, 70°C, 95°C, 100°C, 110°C, 110°C, 100°C, 90°C, and the coating speed is 20-40m / min.

[0058] In a preferred embodiment, the coating method in step S2 and step S4 is blade coating or slit coating.

[0059] In a preferred embodiment, the laminating pressure in step S2 is 1-1.5 Kg, and the laminating pressure in step S3 is 2-3 Kg.

[0060] In a preferred embodiment, the aging conditions in step S5 are: temperature 50-55°C, time 48 hours or temperature 30-35°C, time 72 hours.

[0061] The above is the overall concept of the present invention, and detailed embodiments and comparative examples are provided below on the basis of the overall concept of the present invention to further illustrate the present invention.

[0062] Example 1

[0063] A double-sided adhesive tape for bonding and fixing a polishing pad comprises a first release layer, a first pressure-sensitive adhesive layer, a substrate layer, a second pressure-sensitive adhesive layer and a second release layer which are sequentially stacked; a preparation method thereof comprises the following steps:

[0064] Pre-prepare the acrylate polymer:

[0065] 1) By weight, 50 parts of butyl acrylate, 40 parts of isooctyl acrylate, 2 parts of β-carboxyethyl acrylate, 3 parts of acrylic acid, 0.3 parts of 2-hydroxyethyl acrylate, and 4.7 parts of vinyl acetate were uniformly mixed to obtain a mixed monomer, which was divided into a first part of monomers and a second part of monomers in a mass ratio of 3:2;

[0066] 2) The first part of the monomers is put into a reactor, and toluene accounting for 20% of the total mass of the first part of the monomers and ethyl acetate equal to the mass of the toluene are added, and the mixture is heated to 68° C. with nitrogen, and azobisisobutyl cyanide accounting for 0.1% of the total mass of the first part of the monomers is added, and the reaction is carried out for 1.5 hours. The temperature is raised to 78° C. and the remaining second part of the monomers are added dropwise, and the mixture is added dropwise after 1.5 hours; the reaction is continued for 0.5 hours, and azobisisobutyl cyanide accounting for 0.2% of the total mass of the mixed monomers is added, and the reaction is continued at 78° C. for 2 hours. The mixture is cooled to below 45° C. and discharged to obtain an acrylate polymer having a glass transition temperature of -42° C., a weight average molecular weight of 480,000, and a molecular weight distribution of 8.

[0067] S1. By weight, 100 parts of the acrylate polymer prepared in this example were placed in a stainless steel barrel, 20 parts of a tackifying resin (including 12 parts of a terpene phenol resin TP2040 and 8 parts of RE100F) were added, and the mixture was stirred for 20 minutes. Then, 0.8 parts of an isocyanate curing agent (L-75) was added, and the mixture was stirred for 30 minutes to obtain a first adhesive pre-coating liquid, which was sealed for later use.

[0068] S2. By weight, 100 parts of the acrylate polymer prepared in this example were placed in a stainless steel barrel, 0.8 parts of isocyanate curing agent (L-75) were added, and stirred for 30 minutes to obtain a second adhesive pre-coating liquid, which was sealed for later use;

[0069] S3, evenly coating the first adhesive pre-coating liquid on the release surface of the first release layer (light flat release film), controlling the adhesive thickness to 35 μm, using 8 continuous ovens for drying and curing, the oven temperatures are set as follows: 60°C, 70°C, 95°C, 100°C, 110°C, 110°C, 100°C, 90°C, and passing through the oven at a speed of 35 m / min (the length of each oven is 4 m) to form a first pressure-sensitive adhesive layer, 1 kg laminating pressure, laminating the adhesive surface to the surface of the substrate layer (polyester film with a thickness of 25 μm), and winding to obtain a semi-finished product;

[0070] S4. Evenly apply the second adhesive pre-coating liquid on the bottom surface of the substrate layer, control the adhesive thickness to 40μm, and use 8-section continuous oven for drying and curing. The oven temperature settings are: 60℃, 70℃, 95℃, 100℃, 110℃, 110℃, 100℃, 90℃, and pass through the oven at a speed of 25m / min to form a second pressure-sensitive adhesive layer. With a bonding pressure of 2Kg, bond the second release layer (square grid release film DT50, grid size: 500*500μm, line width 150μm, line height 12μm) on the adhesive surface, reel it up, and mature it at 55℃ for 48H to obtain a double-sided tape for bonding and fixing the polishing pad.

[0071] Example 2

[0072] A double-sided adhesive tape for bonding and fixing a polishing pad comprises a first release layer, a first pressure-sensitive adhesive layer, a substrate layer, a second pressure-sensitive adhesive layer and a second release layer which are sequentially stacked; a preparation method thereof comprises the following steps:

[0073] Pre-prepare the acrylate polymer:

[0074] 1) 55 parts of butyl acrylate, 35 parts of isooctyl acrylate, 2 parts of β-carboxyethyl acrylate, 3 parts of acrylic acid, 0.3 parts of 2-hydroxyethyl acrylate, and 4.7 parts of vinyl acetate were mixed uniformly by weight to obtain a mixed monomer, which was divided into a first part of monomers and a second part of monomers in a mass ratio of 3:2;

[0075] 2) The first part of the monomers is put into a reactor, and toluene accounting for 20% of the total mass of the first part of the monomers and ethyl acetate equal to the mass of the toluene are added, and the mixture is heated to 68° C. with nitrogen, and azobisisobutyl cyanide accounting for 0.1% of the total mass of the first part of the monomers is added, and the reaction is carried out for 1.5 hours. The temperature is raised to 78° C. and the remaining second part of the monomers are added dropwise, and the addition is completed within 1.5 hours; then the reaction is continued for 0.5 hours, and azobisisobutyl cyanide accounting for 0.2% of the total mass of the mixed monomers is added, and the reaction is continued at 78° C. for 2 hours. The mixture is cooled to below 45° C. and discharged to obtain an acrylate polymer having a glass transition temperature of -42° C., a weight average molecular weight of 500,000, and a molecular weight distribution of 12.

[0076] S1. By weight, 100 parts of the acrylate polymer prepared in this example were placed in a stainless steel barrel, 30 parts of a tackifying resin (including 18 parts of terpene phenol resin TP2040 and 12 parts of RE100F) were added, and the mixture was stirred for 20 minutes. Then, 1.2 parts of an isocyanate curing agent (L-75) was added, and the mixture was stirred for 30 minutes to obtain a first adhesive pre-coating liquid, which was sealed for standby use.

[0077] S2. By weight, 100 parts of the acrylate polymer prepared in this example were placed in a stainless steel barrel, 0.8 parts of isocyanate curing agent (L-75) were added, and stirred for 30 minutes to obtain a second adhesive pre-coating liquid, which was sealed for later use;

[0078] S3, evenly coating the first adhesive pre-coating liquid on the release surface of the first release layer (light flat release film), controlling the adhesive thickness to 35 μm, using 8 continuous ovens for drying and curing, the oven temperatures are set as follows: 60°C, 70°C, 95°C, 100°C, 110°C, 110°C, 100°C, 90°C, and passing through the oven at a speed of 35 m / min (the length of each oven is 4 m) to form a first pressure-sensitive adhesive layer, 1 kg laminating pressure, laminating the adhesive surface to the surface of the substrate layer (polyester film with a thickness of 25 μm), and winding to obtain a semi-finished product;

[0079] S4. Evenly apply the second adhesive pre-coating liquid on the bottom surface of the substrate layer, control the adhesive thickness to 40μm, and use 8-section continuous oven for drying and curing. The oven temperature settings are: 60℃, 70℃, 95℃, 100℃, 110℃, 110℃, 100℃, 90℃, and pass through the oven at a speed of 25m / min to form a second pressure-sensitive adhesive layer. With a bonding pressure of 2Kg, bond the second release layer (square grid release film DT80, grid size: 800*800μm, line width 150μm, line height 9μm) on the adhesive surface, reel it up, and mature it at 55℃ for 48H to obtain a double-sided tape for bonding and fixing the polishing pad.

[0080] Example 3

[0081] A double-sided adhesive tape for bonding and fixing a polishing pad comprises a first release layer, a first pressure-sensitive adhesive layer, a substrate layer, a second pressure-sensitive adhesive layer and a second release layer which are sequentially stacked; a preparation method thereof comprises the following steps:

[0082] Pre-prepare the acrylate polymer:

[0083] 1) By weight, 50 parts of butyl acrylate, 40 parts of isooctyl acrylate, 2 parts of β-carboxyethyl acrylate, 5 parts of acrylic acid, 0.3 parts of 2-hydroxyethyl acrylate, and 4.7 parts of vinyl acetate were mixed uniformly to obtain a mixed monomer, which was divided into a first part of monomers and a second part of monomers in a mass ratio of 3:2;

[0084] 2) The first part of the monomers is put into a reactor, and toluene accounting for 20% of the total mass of the first part of the monomers and ethyl acetate equal to the mass of the toluene are added, and the mixture is heated to 68° C. with nitrogen, and azobisisobutyl cyanide accounting for 0.1% of the total mass of the first part of the monomers is added, and the reaction is carried out for 1.5 hours. The temperature is raised to 78° C. and the remaining second part of the monomers are added dropwise, and the addition is completed within 1.5 hours; then the reaction is continued for 0.5 hours, and azobisisobutyl cyanide accounting for 0.2% of the total mass of the mixed monomers is added, and the reaction is continued at 78° C. for 2 hours, and the temperature is lowered to below 45° C. and the material is discharged to obtain an acrylate polymer having a glass transition temperature of -38° C., a weight average molecular weight of 480,000, and a molecular weight distribution of 8.

[0085] S1. By weight, 100 parts of the acrylate polymer prepared in this example were placed in a stainless steel barrel, 20 parts of a tackifying resin (including 12 parts of a terpene phenol resin TP2040 and 8 parts of RE100F) were added, and the mixture was stirred for 20 minutes. Then, 0.8 parts of an isocyanate curing agent (L-75) was added, and the mixture was stirred for 30 minutes to obtain a first adhesive pre-coating liquid, which was sealed for later use.

[0086] S2. By weight, 100 parts of the acrylate polymer prepared in this example were placed in a stainless steel barrel, 0.84 parts of a curing agent (including 0.8 parts of an isocyanate curing agent L-75 and 0.04 parts of an epoxy curing agent GA240) were added, and the mixture was stirred for 30 minutes to obtain a second adhesive pre-coating liquid, which was sealed for later use;

[0087] S3, evenly coating the first adhesive pre-coating liquid on the release surface of the first release layer (light flat release film), controlling the adhesive thickness to 35 μm, using 8 continuous ovens for drying and curing, the oven temperatures are set as follows: 60°C, 70°C, 95°C, 100°C, 110°C, 110°C, 100°C, 90°C, and passing through the oven at a speed of 35 m / min (the length of each oven is 4 m) to form a first pressure-sensitive adhesive layer, 1 kg laminating pressure, laminating the adhesive surface to the surface of the substrate layer (polyester film with a thickness of 25 μm), and winding to obtain a semi-finished product;

[0088] S4. Evenly apply the second adhesive pre-coating liquid on the bottom surface of the substrate layer, control the adhesive thickness to 40μm, and use 8-section continuous oven for drying and curing. The oven temperature settings are: 60℃, 70℃, 95℃, 100℃, 110℃, 110℃, 100℃, 90℃, and pass through the oven at a speed of 25m / min to form a second pressure-sensitive adhesive layer. With a bonding pressure of 2Kg, bond the second release layer (square grid release film DT80, grid size: 800*800μm, line width 150μm, line height 9μm) on the adhesive surface, reel it up, and mature it at 55℃ for 48H to obtain a double-sided tape for bonding and fixing the polishing pad.

[0089] Example 4

[0090] A double-sided adhesive tape for bonding and fixing a polishing pad comprises a first release layer, a first pressure-sensitive adhesive layer, a substrate layer, a second pressure-sensitive adhesive layer and a second release layer which are sequentially stacked; a preparation method thereof comprises the following steps:

[0091] Pre-prepare the acrylate polymer:

[0092] 1) By weight, 50 parts of butyl acrylate, 40 parts of isooctyl acrylate, 2 parts of β-carboxyethyl acrylate, 5 parts of acrylic acid, 0.1 parts of 2-hydroxyethyl acrylate, and 4 parts of vinyl acetate are mixed uniformly to obtain a mixed monomer, which is divided into a first part of monomers and a second part of monomers in a mass ratio of 3:2;

[0093] 2) The first part of the monomers is put into a reactor, and toluene accounting for 20% of the total mass of the first part of the monomers and ethyl acetate equal to the mass of the toluene are added, and the mixture is heated to 68° C. with nitrogen, and azobisisobutyl cyanide accounting for 0.1% of the total mass of the first part of the monomers is added, and the reaction is carried out for 1.5 hours. The temperature is raised to 78° C. and the remaining second part of the monomers are added dropwise, and the addition is completed within 1.5 hours; then the reaction is continued for 0.5 hours, and azobisisobutyl cyanide accounting for 0.2% of the total mass of the mixed monomers is added, and the reaction is continued at 78° C. for 2 hours. The mixture is cooled to below 45° C. and discharged to obtain an acrylate polymer having a glass transition temperature of -42° C., a weight average molecular weight of 580,000, and a molecular weight distribution of 8.

[0094] S1. By weight, 100 parts of the acrylate polymer prepared in this example were placed in a stainless steel barrel, 25 parts of a tackifying resin (including 15 parts of terpene phenol resin TP2040 and 10 parts of RE100F) were added, and the mixture was stirred for 20 minutes. Then, 0.8 parts of an isocyanate curing agent (L-75) was added, and the mixture was stirred for 30 minutes to obtain a first adhesive pre-coating liquid, which was sealed for later use.

[0095] S2. By weight, 100 parts of the acrylate polymer prepared in this example were placed in a stainless steel barrel, 0.84 parts of a curing agent (including 0.8 parts of an isocyanate curing agent L-75 and 0.04 parts of an epoxy curing agent GA240) were added, and the mixture was stirred for 30 minutes to obtain a second adhesive pre-coating liquid, which was sealed for later use;

[0096] S3, evenly coating the first adhesive pre-coating liquid on the release surface of the first release layer (light flat release film), controlling the adhesive thickness to 35 μm, using 8 continuous ovens for drying and curing, the oven temperatures are set as follows: 60°C, 70°C, 95°C, 100°C, 110°C, 110°C, 100°C, 90°C, and passing through the oven at a speed of 35 m / min (the length of each oven is 4 m) to form a first pressure-sensitive adhesive layer, 1 kg laminating pressure, laminating the adhesive surface to the surface of the substrate layer (polyester film with a thickness of 25 μm), and winding to obtain a semi-finished product;

[0097] S4. Evenly apply the second adhesive pre-coating liquid on the bottom surface of the substrate layer, control the adhesive thickness to 40μm, and use 8-section continuous oven for drying and curing. The oven temperature settings are: 60℃, 70℃, 95℃, 100℃, 110℃, 110℃, 100℃, 90℃, and pass through the oven at a speed of 25m / min to form a second pressure-sensitive adhesive layer. With a bonding pressure of 2Kg, bond the second release layer (square grid release film DT150, grid size: 1500*1500μm, line width 250μm, line height 9μm) on the adhesive surface, reel it up, and mature it at 55℃ for 48H to obtain a double-sided tape for bonding and fixing the polishing pad.

[0098] Comparative Example 1

[0099] A double-sided adhesive tape for bonding and fixing a polishing pad comprises a first release layer, a first pressure-sensitive adhesive layer, a substrate layer, a second pressure-sensitive adhesive layer and a second release layer which are sequentially stacked; a preparation method thereof comprises the following steps:

[0100] Pre-prepare the acrylate polymer:

[0101] 1) By weight, 50 parts of butyl acrylate, 40 parts of isooctyl acrylate, 2 parts of β-carboxyethyl acrylate, 5 parts of acrylic acid, 0.3 parts of 2-hydroxyethyl acrylate, and 4.7 parts of vinyl acetate were mixed uniformly to obtain a mixed monomer, which was divided into a first part of monomers and a second part of monomers in a mass ratio of 3:2;

[0102] 2) The first part of the monomers is put into a reactor, and toluene accounting for 20% of the total mass of the first part of the monomers and ethyl acetate equal to the mass of the toluene are added, and the mixture is heated to 68° C. with nitrogen, and azobisisobutyl cyanide accounting for 0.1% of the total mass of the first part of the monomers is added, and the reaction is carried out for 1.5 hours. The temperature is raised to 78° C. and the remaining second part of the monomers are added dropwise, and the mixture is added dropwise after 1.5 hours; the reaction is then continued for 0.5 hours, and azobisisobutyl cyanide accounting for 0.2% of the total mass of the mixed monomers is added, and the reaction is continued at 78° C. for 2 hours. The mixture is cooled to below 45° C. and discharged to obtain an acrylate polymer having a glass transition temperature of -38° C., a weight average molecular weight of 380,000, and a molecular weight distribution of 8.

[0103] S1. By weight, 100 parts of the acrylate polymer prepared in this example were placed in a stainless steel barrel, 20 parts of a tackifying resin (including 12 parts of a terpene phenol resin TP2040 and 8 parts of RE100F) were added, and the mixture was stirred for 20 minutes. Then, 0.8 parts of an isocyanate curing agent (L-75) was added, and the mixture was stirred for 30 minutes to obtain a first adhesive pre-coating liquid, which was sealed for later use.

[0104] S2. 100 parts by weight of an acrylate polymer (the acrylate polymer prepared in Example 1 is used here) are placed in a stainless steel barrel, 0.8 parts of an isocyanate curing agent (L-75) are added, and the mixture is stirred for 30 minutes to obtain a second adhesive pre-coating liquid, which is then sealed for later use.

[0105] S3, evenly coating the first adhesive pre-coating liquid on the release surface of the first release layer (light flat release film), controlling the adhesive thickness to 35 μm, using 8 continuous ovens for drying and curing, the oven temperatures are set as follows: 60°C, 70°C, 95°C, 100°C, 110°C, 110°C, 100°C, 90°C, and passing through the oven at a speed of 35 m / min (the length of each oven is 4 m) to form a first pressure-sensitive adhesive layer, 1 kg laminating pressure, laminating the adhesive surface to the surface of the substrate layer (polyester film with a thickness of 25 μm), and winding to obtain a semi-finished product;

[0106] S4. Evenly apply the second adhesive pre-coating liquid on the bottom surface of the substrate layer, control the adhesive thickness to 40μm, and use 8-section continuous oven for drying and curing. The oven temperature settings are: 60℃, 70℃, 95℃, 100℃, 110℃, 110℃, 100℃, 90℃, and pass through the oven at a speed of 25m / min to form a second pressure-sensitive adhesive layer. With a bonding pressure of 2Kg, bond the second release layer (square grid release film DT50, grid size: 500*500μm, line width 150μm, line height 12μm) on the adhesive surface, reel it up, and mature it at 55℃ for 48H to obtain a double-sided tape for bonding and fixing the polishing pad.

[0107] Comparative Example 2

[0108] A double-sided adhesive tape for bonding and fixing a polishing pad comprises a first release layer, a first pressure-sensitive adhesive layer, a substrate layer, a second pressure-sensitive adhesive layer and a second release layer which are sequentially stacked; a preparation method thereof comprises the following steps:

[0109] Pre-prepare the acrylate polymer:

[0110] 1) By weight, 50 parts of butyl acrylate, 40 parts of isooctyl acrylate, 2 parts of β-carboxyethyl acrylate, 5 parts of acrylic acid, 0.3 parts of 2-hydroxyethyl acrylate, and 4.7 parts of vinyl acetate were mixed uniformly to obtain a mixed monomer, which was divided into a first part of monomers and a second part of monomers in a mass ratio of 3:2;

[0111] 2) The first part of the monomers is put into a reactor, and toluene accounting for 20% of the total mass of the first part of the monomers and ethyl acetate equal to the mass of the toluene are added, and the mixture is heated to 68° C. with nitrogen, and azobisisobutyl cyanide accounting for 0.1% of the total mass of the first part of the monomers is added, and the reaction is carried out for 1.5 hours. The temperature is raised to 78° C. and the remaining second part of the monomers are added dropwise, and the addition is completed within 1.5 hours; then the reaction is continued for 0.5 hours, and azobisisobutyl cyanide accounting for 0.2% of the total mass of the mixed monomers is added, and the reaction is continued at 78° C. for 2 hours, and the temperature is lowered to below 45° C. to discharge the material to obtain an acrylate polymer having a glass transition temperature of -42, a weight average molecular weight of 480,000, and a molecular weight distribution of 8.

[0112] S1. By weight, 100 parts of the acrylate polymer prepared in this example were placed in a stainless steel barrel, 20 parts of a tackifying resin (including 12 parts of a terpene phenol resin TP2040 and 8 parts of RE100F) were added, and the mixture was stirred for 20 minutes. Then, 0.8 parts of an isocyanate curing agent (L-75) was added, and the mixture was stirred for 30 minutes to obtain a first adhesive pre-coating liquid, which was sealed for later use.

[0113] S2. By weight, 100 parts of the acrylate polymer prepared in this example were placed in a stainless steel barrel, 0.8 parts of isocyanate curing agent (L-75) were added, and stirred for 30 minutes to obtain a second adhesive pre-coating liquid, which was sealed for later use;

[0114] S3, evenly coating the first adhesive pre-coating liquid on the release surface of the first release layer (light flat release film), controlling the adhesive thickness to 35 μm, using 8 continuous ovens for drying and curing, the oven temperatures are set as follows: 60°C, 70°C, 95°C, 100°C, 110°C, 110°C, 100°C, 90°C, and passing through the oven at a speed of 35 m / min (the length of each oven is 4 m) to form a first pressure-sensitive adhesive layer, 1 kg laminating pressure, laminating the adhesive surface to the surface of the substrate layer (polyester film with a thickness of 25 μm), and winding to obtain a semi-finished product;

[0115] S4. Evenly apply the second adhesive pre-coating liquid on the bottom surface of the substrate layer, control the adhesive thickness to 40μm, and use 8-section continuous oven for drying and curing. The oven temperature settings are: 60℃, 70℃, 95℃, 100℃, 110℃, 110℃, 100℃, 90℃, and pass through the oven at a speed of 25m / min to form a second pressure-sensitive adhesive layer. With a bonding pressure of 2Kg, bond the second release layer (square grid release film DT501, grid size: 500*500μm, line width 100μm, line height 9μm) on the adhesive surface, reel it up, and mature it at 55℃ for 48H to obtain a double-sided tape for bonding and fixing the polishing pad.

[0116] The raw material information of Examples 1-4 and Comparative Examples 1-2 is shown in Table 1 (the raw material ratio units in the table are all parts by weight):

[0117] Table 1

[0118]

[0119]

[0120] The following performance tests were performed on Examples 1 to 4 and Comparative Examples 1 to 2:

[0121] 1.Thickness assessment: GB / T 7125-2014;

[0122] 2. Peel force evaluation: GB / T 2792-2014;

[0123] 3. Ring initial adhesion assessment: GB / T 31125-2014;

[0124] 4. Retention assessment: GB / T 4851-2014;

[0125] 5. Water resistance evaluation: Cut the standard size specimens for peeling strength test, attach them to silicon carbide sheet and tetrafluoroethylene sheet, and immerse the whole in 23℃ water for 168 hours. Then take out the whole and observe whether there is any warping phenomenon.

[0126] 6. Removability evaluation: Cut the strips of standard size for peeling force test, attach them to silicon carbide sheet and tetrafluoroethylene sheet, and place the whole in a high temperature and high humidity box for 168 hours. The humidity and heat conditions are: temperature 65℃, humidity 95%RH. Then take out the whole, observe whether there is any warping or debonding phenomenon, and peel the pressure-sensitive tape from the silicon carbide sheet, and test it under the same test conditions as the peeling force test, and observe whether there is any glue residue on the silicon carbide sheet.

[0127] 7. Exhaust performance: Cut the strips of standard size for peeling force test, attach them to silicon carbide sheet and tetrafluoroethylene sheet, and place the whole in a high temperature and high humidity box for 168 hours. The humidity and heat conditions are: temperature 65℃, humidity 95%RH. Then take out the whole and observe whether there are bubbles in the adhesive layer bonding area.

[0128] 8. Molecular weight and molecular weight distribution: GPC test;

[0129] 9. Glass transition temperature: DSC test.

[0130] The test results are shown in Table 2 below:

[0131] Table 2

[0132]

[0133]

[0134] As can be seen from Table 2 above, the low molecular weight acrylic ester design in Comparative Example 1 does not have the property of removing without residue; the mesh shape of the mesh release material in Comparative Example 2 also has a very large influence on the lamination and air-discharging properties. Examples 1 to 4 show that the pressure-sensitive adhesive tape for bonding and fixing the polishing pad prepared by the present invention has good comprehensive properties in terms of adhesion, water resistance, air-discharging properties, and removal properties in the physical property tests simulating the polishing base as a high surface tension silicon carbide material and a low surface tension tetrafluoroethylene material, and can greatly improve the efficiency and yield of the product in the application of chemical grinding and polishing processes.

[0135] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to specific details.

Claims

1. A double-sided tape for bonding and fixing a polishing pad, characterized in that: It comprises a first release layer, a first pressure-sensitive adhesive layer, a substrate layer, a second pressure-sensitive adhesive layer and a second release layer which are stacked in sequence; The first pressure-sensitive adhesive layer is obtained by coating a first adhesive pre-coating liquid and then curing it. The raw materials for preparing the first adhesive pre-coating liquid include the following components in parts by weight: 100 parts of acrylate polymer, 15-30 parts of tackifying resin, and 0.25-1.5 parts of curing agent.

2. The double-sided adhesive tape for bonding and fixing the polishing pad according to claim 1, characterized in that: The acrylic ester polymer is prepared by a solution polymerization method from acrylic soft monomers, acrylic hard monomers and acrylic functional monomers. The DSC glass transition temperature of the acrylic ester polymer is -30 to -50°C, the weight average molecular weight is 450,000-600,000, and the molecular weight distribution is 5-15.

3. The double-sided adhesive tape for bonding and fixing the polishing pad according to claim 2, characterized in that: The acrylic acid ester polymer is prepared by the following method: 1) By weight, 40-60 parts of butyl acrylate, 30-50 parts of isooctyl acrylate, 1-4 parts of β-carboxyethyl acrylate, 1.5-6 parts of acrylic acid, 0.15-0.6 parts of 2-hydroxyethyl acrylate, and 2.5-9 parts of vinyl acetate are mixed uniformly to obtain a mixed monomer, which is divided into a first part of monomers and a second part of monomers in a mass ratio of 3:2; 2) The first part of the monomers is put into a reactor, and toluene accounting for 20% of the total mass of the first part of the monomers and ethyl acetate equal to the toluene are added, and the mixture is heated to 65-70° C. with nitrogen, and azobisisobutyl cyanide accounting for 0.1% of the total mass of the first part of the monomers is added, and the reaction is carried out for 1-3 hours. The temperature is raised to 75° C.-80° C. and the remaining second part of the monomers are added dropwise, and the mixture is finished after 1-3 hours; then the reaction is continued for 15-60 minutes, and azobisisobutyl cyanide accounting for 0.2% of the total mass of the mixed monomers is added, and the reaction is continued at 78-82° C. for 1-4 hours, and the temperature is lowered and the material is discharged to obtain an acrylate polymer.

4. The double-sided adhesive tape for bonding and fixing the polishing pad according to claim 3, characterized in that: The acrylic acid ester polymer is prepared by the following method: 1) By weight, 50 parts of butyl acrylate, 40 parts of isooctyl acrylate, 2 parts of β-carboxyethyl acrylate, 3 parts of acrylic acid, 0.3 parts of 2-hydroxyethyl acrylate, and 4.7 parts of vinyl acetate were uniformly mixed to obtain a mixed monomer, which was divided into a first part of monomers and a second part of monomers in a mass ratio of 3:2; 2) The first part of the monomers is put into a reactor, and toluene accounting for 20% of the total mass of the first part of the monomers and ethyl acetate equal to the mass of the toluene are added, and the mixture is heated to 68° C. with nitrogen, and azobisisobutyl cyanide accounting for 0.1% of the total mass of the first part of the monomers is added, and the reaction is carried out for 1.5 hours. The temperature is raised to 78° C. and the remaining second part of the monomers are added dropwise, and the mixture is added dropwise after 1.5 hours; then the reaction is continued for 0.5 hours, and azobisisobutyl cyanide accounting for 0.2% of the total mass of the mixed monomers is added, and the reaction is continued at 78° C. for 2 hours. The temperature is lowered to below 45° C. and the material is discharged to obtain an acrylate polymer.

5. The double-sided adhesive tape for bonding and fixing the polishing pad according to claim 1, characterized in that: The second pressure-sensitive adhesive layer is obtained by coating a second adhesive pre-coating liquid and then curing it. The raw materials for preparing the second adhesive pre-coating liquid include the following components in parts by weight: 100 parts of acrylate polymer and 0.3-1.5 parts of curing agent.

6. The double-sided adhesive tape for bonding and fixing a polishing pad according to claim 1, characterized in that: The first release layer is a flat release layer, and the second release layer is a grid release layer, and the grid shape is either a square or a rhombus; The mesh shape size of the mesh release layer is 550*550μm to 2000*2000μm.

7. The double-sided tape for bonding and fixing a polishing pad according to claim 1, characterized in that: The substrate layer is a polyester film, the surface tension of both sides of the film is greater than 44 dynes, and the thickness is 12 to 50 μm.

8. The double-sided adhesive tape for bonding and fixing a polishing pad according to claim 1, characterized in that: The tackifying resin is a mixture of a high softening point tackifying resin and a low softening point tackifying resin, wherein the high softening point tackifying resin has a softening point of 100-150°C; and the low softening point tackifying resin has a softening point of 70-100°C; The high softening point tackifying resin is at least one of terpene phenolic resin, rosin resin and modified rosin resin, and the low softening point tackifying resin is at least one of rosin resin and rosin modified resin.

9. The double-sided tape for bonding and fixing a polishing pad according to claim 1, characterized in that: The curing agent is at least one of an isocyanate curing agent or an epoxy curing agent.

10. A method for preparing a double-sided adhesive tape for bonding and fixing a polishing pad as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Mix 100 parts of acrylate polymer and 15-30 parts of tackifying resin by weight and stir for 20-30 minutes, then add 0.25-1.5 parts of curing agent and stir for 20-30 minutes to obtain a first adhesive pre-coating liquid; S2, evenly coating the first adhesive pre-coating liquid on the release surface of the first release layer, drying and curing at 60-110° C. to form a first pressure-sensitive adhesive layer, and laminating the adhesive surface on the surface of the substrate layer to obtain a semi-finished product; S3, mixing 100 parts of acrylate polymer and 0.3-1.5 parts of curing agent by weight and stirring for 20-30 minutes to obtain a second adhesive pre-coating liquid; S4, evenly coating the second adhesive pre-coating liquid on the bottom surface of the substrate layer, drying and curing at 60-110° C. to form a second pressure-sensitive adhesive layer, attaching a second release layer to the adhesive surface, winding up, and ripening to obtain the double-sided adhesive tape for bonding and fixing the polishing pad.

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