JP6303482B2 - Urethane composition, cured product, and abrasive - Google Patents

Description

  The present invention relates to a urethane composition that can be particularly suitably used as an abrasive.

  In fields requiring high surface flatness such as liquid crystal displays (LCDs), glass substrates for hard disks, silicon wafers, and semiconductor devices, abrasives using urethane compositions have been widely used.

  As a urethane composition that can be used for the abrasive, for example, a two-component urethane composition containing a main agent containing an isocyanate group-terminated urethane prepolymer (A) and a curing agent containing an isocyanate group-reactive compound (B). The urethane prepolymer (A) comprises a polyisocyanate (a1), an aromatic polyester polyol (a2) and a polyether polyol (a3) as polyol components (a2) / (a3) = 5/95. Is an isocyanate group equivalent of 250 to 700 obtained by reacting together at a ratio of ~ 70/30 (mass ratio), and the aromatic polyester polyol (a2) has 2 to 11 aromatic rings in the molecular chain. A urethane composition for rough polishing such as a urethane composition (see, for example, Patent Document 1) characterized by Wet composition containing urethane resin (A), carbodiimide compound (B) and organic solvent (C) obtained by reacting polyol (a1) containing polyester polyol with polyisocyanate (a2) containing aromatic polyisocyanate. A urethane composition for finish polishing such as a urethane composition for a film (for example, see Patent Document 2) is disclosed.

  As described above, as the abrasive, various abrasives such as rough cutting, medium cutting, and finishing are required, and different resin compositions have been used.

WO2011 / 001755 Publication JP 2012-102182 A

  The problem to be solved by the present invention is to provide a urethane composition in which the resulting cured product gives different hardness depending on the temperature. Especially when used as an abrasive, it is suitable for rough cutting by adjusting the heating. It is to provide a urethane composition that does not require the use of a separate resin composition as a raw material for an abrasive such as an abrasive or a finishing abrasive.

  The present invention is a urethane composition characterized in that the glass transition temperature in a dynamic viscoelastic spectrum measured at a frequency of 1.6 Hz of the obtained cured product is 0 ° C. or higher, a cured product obtained using the same, And an abrasive is provided.

  Since the urethane composition of the present invention expresses different hardness depending on the temperature, particularly when used as an abrasive, by adjusting the heating, it can be used as a raw material for an abrasive such as an abrasive for roughing and an abrasive for finishing. There is no need to use a separate resin composition. Therefore, the urethane composition of the present invention can be particularly suitably used as a material for abrasives such as polishing cloths and polishing pads.

  The urethane composition of the present invention provides a cured product having a glass transition temperature of 0 ° C. or higher in a dynamic viscoelastic spectrum measured at a frequency of 1.6 Hz.

  The glass transition temperature must be 0 ° C. or higher. When the glass transition temperature deviates from the above range, the change in hardness is very small especially in the temperature condition (range of 20 to 150 ° C.) during polishing, and abrasives such as roughing abrasives and finishing abrasives. Cannot be provided by one type of urethane composition. The glass transition temperature is in the range of 0 to 50 ° C. because the change in hardness due to temperature is large, and it becomes easier to use as various abrasives such as roughing abrasives and finishing abrasives. Preferably, the range of 5-40 degreeC is more preferable, The range of 10-30 degreeC is still more preferable, The range of 15-25 degreeC is especially preferable.

  The glass transition temperature is determined based on JISK7198-1991 using a dynamic viscoelasticity measuring device (“DMS6100” manufactured by Hitachi High-Tech Science Co., Ltd.) as a temperature rise rate of 5 ° C. / Minute, measurement frequency 1.6 Hz, temperature range; a value calculated as an extrapolated decrease start temperature of E ′ measured under the conditions of −100 to 200 ° C.

  As the urethane composition, for example, a one-component urethane composition, a two-component curable urethane composition, an ultraviolet curable urethane composition, or the like can be used. These urethane compositions may be used alone or in combination of two or more. Among these, it is preferable to use a two-component curable urethane composition from the viewpoint of easily setting the glass transition temperature within the above range.

  As the two-component curable urethane composition, a urethane composition containing a main agent (i) containing a urethane prepolymer (A) having an isocyanate group, a curing agent (ii), and a microballoon (iii). It is preferable to use it.

  As the urethane prepolymer (A), for example, a product obtained by reacting a polyol, a polyisocyanate, and a chain extender can be used.

  Examples of the polyol include polycarbonate polyol, polyether polyol, polybutadiene polyol, polyester polyol, and polyacryl polyol. These polyols may be used alone or in combination of two or more. Among these, it is preferable to use a polyether polyol because the glass transition temperature is easily set in the above range.

  Examples of the polyether polyol include polyethylene polyol, polypropylene polyol, polytetramethylene polyol, polyoxyethylene polyoxypropylene polyol, and polyoxypropylene polyoxytetramethylene polyol. These polyether polyols may be used alone or in combination of two or more. Among these, polytetramethylene polyol is preferably used, and polytetramethylene glycol is more preferably used from the viewpoint that the glass transition temperature is easily set in the above range.

  The number average molecular weight of the polyol is preferably in the range of 500 to 900, more preferably in the range of 550 to 700, from the viewpoint of easily setting the glass transition temperature within the above range and the mechanical strength. In addition, the number average molecular weight of the said polyol shows the value measured on condition of the following by gel permeation chromatography (GPC) method.

Measuring device: High-speed GPC device (“HLC-8220GPC” manufactured by Tosoh Corporation)
Column: The following columns manufactured by Tosoh Corporation were connected in series.
"TSKgel G5000" (7.8 mm ID x 30 cm) x 1 "TSKgel G4000" (7.8 mm ID x 30 cm) x 1 "TSKgel G3000" (7.8 mm ID x 30 cm) x 1 “TSKgel G2000” (7.8 mm ID × 30 cm) × 1 detector: RI (differential refractometer)
Column temperature: 40 ° C
Eluent: Tetrahydrofuran (THF)
Flow rate: 1.0 mL / min Injection amount: 100 μL (tetrahydrofuran solution with a sample concentration of 0.4 mass%)
Standard sample: A calibration curve was prepared using the following standard polystyrene.

(Standard polystyrene)
"TSKgel standard polystyrene A-500" manufactured by Tosoh Corporation
"TSKgel standard polystyrene A-1000" manufactured by Tosoh Corporation
"TSKgel standard polystyrene A-2500" manufactured by Tosoh Corporation
"TSKgel standard polystyrene A-5000" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-1" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-2" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-4" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-10" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-20" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-40" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-80" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-128" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-288" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-550" manufactured by Tosoh Corporation

  Examples of the polyisocyanate include aromatic polyisocyanates such as 4,4′-diphenylmethane diisocyanate, toluene diisocyanate, naphthalene diisocyanate, phenylene diisocyanate, and xylylene diisocyanate; aliphatics such as ethylene diisocyanate, hexamethylene diisocyanate, and trimethylhexamethylene diisocyanate. Polyisocyanate; alicyclic polyisocyanate such as isophorone diisocyanate, cyclohexane diisocyanate, dicyclohexylmethane diisocyanate, norbornane diisocyanate, hydrogenated xylylene diisocyanate, and the like can be used. These polyisocyanates may be used alone or in combination of two or more. Among these, aromatic polyisocyanate is preferably used, and 4,4′-diphenylmethane diisocyanate is more preferably used from the viewpoint of easily setting the glass transition temperature within the above range and mechanical strength.

  Examples of the chain extender include 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,2-butanediol, 1,3-butanediol, and 2-butyl-2. -Ethyl-1,3-propanediol, 1,2-propanediol, 2-methyl-1,3-propanediol, neopentyl glycol, 2-isopropyl-1,4-butanediol, 2,4-dimethyl-1 , 5-pentanediol 2,4-diethyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, 2-ethyl-1,6-hexanediol, 3,5-heptanediol, 2-methyl Glycol having a branched structure such as 1,8-octanediol, 2- (2-hydroxy-propoxy) -propan-1-ol; ethylene glycol Diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, hexamethylene glycol, 3-methyl-1,5-pentanediol, 4 Chain extenders having hydroxyl groups such as 4,4'-dihydroxydiphenyl, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenylsulfone, hydrogenated bisphenol A, hydroquinone, trimethylolpropane; ethylenediamine, propanediamine, hexanediamine , Chain extenders having an amino group such as isophorone diamine, phenylene diamine, 4,4′-diamino-3,3′-dichlorodiphenylmethane, polyaminochlorophenylmethane compound, and the like can be used. These chain extenders may be used alone or in combination of two or more. Among these, it is preferable to use a glycol having a branched structure from the viewpoint of easily setting the glass transition temperature within the above range and the mechanical strength.

  The number average molecular weight of the chain extender is preferably in the range of 80 to 300 from the viewpoint of mechanical strength. The number average molecular weight of the chain extender indicates a value obtained by measurement in the same manner as the number average molecular weight of the polyol.

  The urethane prepolymer (A) is obtained by reacting the polyol, the polyisocyanate, and the chain extender by a conventionally known method, and has an isocyanate group.

  The molar ratio (NCO / OH) between the hydroxyl group of the polyol and the chain extender and the isocyanate group of the polyisocyanate in obtaining the urethane prepolymer (A) is as follows: A range of 3 to 6.5 is preferable, and a range of 1.5 to 5 is preferable.

  The isocyanate group equivalent of the urethane prepolymer (A) is 200 to 900 g / eq. It is preferable that it is the range of these. In addition, the isocyanate group equivalent of the urethane prepolymer (A) was determined by dissolving the sample in dry toluene and reacting with excess di-n-butylamine solution in accordance with JIS K7301: 2003. -Shows the value obtained by back titrating butylamine with hydrochloric acid standard solution.

  The curing agent (ii) contains a compound having a group containing an active hydrogen atom ([NH] group and / or [OH] group) that reacts with the isocyanate group of the urethane prepolymer (A). For example, aliphatic or alicyclic amine compounds such as ethylenediamine, propanediamine, hexanediamine, and isophoronediamine; phenylenediamine, 4,4′-diamino-3,3′-dichlorodiphenylmethane, polyaminochlorophenylmethane compounds, etc. Aromatic amine compounds; ethylene glycol, diethylene glycol, propanediol, butanediol, hexanediol, neopentylglycol, 3-methyl-1,5-pentanediol, bisphenol A, alkylene oxide adducts of bisphenol A, polyester Ether polyols, polyester polyols, polycaprolactone polyols, and compounds having two or more hydroxyl groups such as polycarbonate polyols can be used. These curing agents may be used alone or in combination of two or more. Among these, it is preferable to use a compound having two or more hydroxyl groups, and more preferable to use ethylene glycol, from the viewpoint of easily setting the glass transition temperature in the above range and the mechanical strength.

  The molar ratio (group containing the active hydrogen atom / NCO) of the group containing the active hydrogen atom of the curing agent (ii) and the isocyanate group of the urethane prepolymer (A) is that of mechanical strength. From the point of view, the range is preferably 0.6 to 1, and more preferably 0.7 to 0.98.

  The microballoon (iii) refers to a hollow bead-like substance formed from a polymer compound raw material, and gas is contained in the bead-like substance. As said gas, air, nitrogen, argon, helium etc. can be used, for example. As a raw material for the microballoon (iii), for example, a resin of polyethylene, polypropylene, polyvinylidene chloride, or polyacrylonitrile can be used.

 The average particle diameter of the microballoon (iii) is preferably 1 to 500 μm, more preferably 1 to 100 μm, and still more preferably 5 to 50 μm from the viewpoint of mechanical strength. In addition, the average particle diameter of the microballoon (iii) indicates the value (μm) of D50 measured using a laser diffraction particle size distribution measuring device “SALD-7000” manufactured by Shimadzu Corporation.

  As the microballoon (iii), for example, “EXPANCEL (registered trademark)” manufactured by Nippon Philite Co., Ltd. can be obtained as a commercial product.

  As content of the said microballoon (iii), it is preferable that it is the range of 0.5-5 mass% in a urethane composition from the point of mechanical strength, and the range of 1-3 mass% is more preferable.

  The two-component curable urethane composition contains the main component (i) containing the urethane prepolymer (A), the curing agent (ii), and the microballoon (iii) as essential components. You may contain another additive as needed.

  Examples of the other additives include urethanization catalysts, abrasive grains, foam stabilizers, fillers, pigments, thickeners, antioxidants, ultraviolet absorbers, surfactants, flame retardants, plasticizers, water, and the like. Can be used. These additives may be used alone or in combination of two or more.

  As a method of obtaining a cured product using the urethane composition, for example, the urethane composition is poured into a mold preheated in a range of 50 to 100 ° C., the lid of the mold is closed, and a temperature of 50 to 100 ° C. A method of obtaining a cured product by curing at a temperature for 30 minutes to 5 hours can be mentioned.

  Moreover, as a method of obtaining an abrasive using the cured product, for example, a method of slicing the cured product in a thickness range of 0.5 to 5 mm using a slicer to obtain an abrasive.

  The abrasive | polishing agent obtained by the said method may be after-cured for 5 to 20 hours in the range of 50-120 degreeC as needed.

  Since the urethane composition of the present invention expresses different hardness depending on the temperature, particularly when used as an abrasive, by adjusting the heating, it can be used as a raw material for an abrasive such as an abrasive for roughing and an abrasive for finishing. There is no need to use a separate resin composition. Therefore, the urethane composition of the present invention can be particularly suitably used as a material for abrasives such as polishing cloths and polishing pads.

  Hereinafter, the present invention will be described in more detail with reference to examples.

[Example 1]
In a four-necked flask equipped with a nitrogen introduction tube, a thermometer, and a stirrer, 1,546.7 parts by mass of 4,4′-diphenylmethane diisocyanate and 654.3 parts by mass of polytetramethylene glycol (number average molecular weight; 650) , 2- (2-hydroxy-propoxy) -propan-1-ol was charged in 61.2 parts by mass, reacted at 60 ° C. for 8 hours under a nitrogen stream, and the isocyanate group equivalent was 240 g / eq. A urethane prepolymer having an isocyanate group was obtained.
Subsequently, 2,488.8 parts by mass of the obtained urethane prepolymer, 236.4 parts by mass of ethylene glycol, and 44.6 parts by mass of a microballoon “EXPANEL 551DE40d42” manufactured by Nippon Philite Co., Ltd. were mixed and stirred to obtain a urethane composition. I got a thing.
Then, 2,000 parts by mass of the obtained urethane composition was immediately poured into a mold (250 mm × 250 mm × 40 mm) preheated to 80 ° C., the lid of the mold was immediately closed, and left at 80 ° C. for 1 hour. Thereafter, the foamed molded product was taken out. The foamed molded product taken out was cut to a thickness of 1.3 mm with a slicer and aftercured at 80 ° C. for 16 hours to obtain a foamed polishing pad.

[Comparative Example 1]
In a four-necked flask equipped with a nitrogen inlet tube, a thermometer, and a stirrer, 812 parts by mass of toluene diisocyanate, 1,110.7 parts by mass of polytetramethylene glycol (number average molecular weight; 650), and 77.3 parts by mass of diethylene glycol Parts were mixed and reacted at 60 ° C. for 8 hours under a nitrogen stream, and the isocyanate group equivalent was 450 g / eq. The urethane prepolymer having an isocyanate group was obtained.
Next, 2,000 parts by mass of the obtained urethane prepolymer, 564.1 parts by mass of 4,4′-methylene-bis-o-chloroaniline melted at 120 ° C., microballoon “EXPANEL 551DE40d42” manufactured by Nippon Philite Co., Ltd. 42 parts by mass were mixed and stirred to obtain a urethane composition.
Then, 2,000 parts by mass of the obtained urethane composition was immediately poured into a mold (250 mm × 250 mm × 40 mm) preheated to 80 ° C., the lid of the mold was immediately closed, and left at 80 ° C. for 1 hour. Thereafter, the foamed molded product was taken out. The foamed molded product taken out was cut to a thickness of 1.3 mm with a slicer and aftercured at 80 ° C. for 16 hours to obtain a foamed polishing pad.

[Measurement method of glass transition temperature]
The glass transition temperature of the polishing pad obtained in the examples and comparative examples was determined by using a dynamic viscoelasticity measuring device (“DMS6100” manufactured by Hitachi High-Tech Science Co., Ltd.) based on JISK7198-1991. It was calculated as an extrapolated decrease start temperature of E ′ measured under conditions of a temperature rising rate of 5 ° C./min, a measurement frequency of 1.6 Hz, a temperature range; −100 to 200 ° C.

[Measurement method of JISA hardness]
The hardness of the polishing pad obtained in the examples and comparative examples was evaluated as a type A as a spring hardness test in accordance with JIS K7312-1996 (hardness test).

  In Example 1 which is an abrasive of the present invention, the change in JIS hardness at 20 ° C., 90 ° C., and 150 ° C. is large, and separate abrasives are used as abrasives such as roughing abrasives and finishing abrasives. It turns out that it is not necessary to use it.

  On the other hand, Comparative Example 1 is an embodiment using a urethane composition having a glass transition temperature of less than 0 ° C., but there was little change in JIS hardness at 20 ° C., 90 ° C., and 150 ° C.

Claims (5)

Containing a main agent (i) containing a urethane prepolymer (A) having an isocyanate group, a curing agent (ii), and a microballoon (iii);
The urethane prepolymer (A) is obtained by reacting a polyol having a number average molecular weight in the range of 500 to 900, an aromatic polyisocyanate, and a glycol having a branched structure,
A urethane composition having a glass transition temperature in a dynamic viscoelastic spectrum measured at a frequency of 1.6 Hz of the obtained cured product in a range of 5 to 40 ° C. The urethane prepolymer (A) is reacted with a polyol having a number average molecular weight in the range of 500 to 900, 4,4′-diphenylmethane diisocyanate, and a glycol having a number average molecular weight in the range of 80 to 300 and having a branched structure. The urethane composition according to claim 1 , wherein the urethane composition is obtained. The urethane composition according to claim 1 or 2, wherein the curing agent (ii) contains a compound (B) having two or more hydroxyl groups. A cured product obtained by using the urethane composition according to any one of claims 1 to 3 . An abrasive obtained using the urethane composition according to any one of claims 1 to 3 .