JPWO2019017366A1 - Adhesive composition - Google Patents

Abstract

To provide an adhesive composition which is excellent in adhesiveness, coatability, and solvent resistance for favorably adhering a urethane porous layer and a substrate film. An amorphous polyester resin (A) having a number average molecular weight of 5,000 to 40,000, a glass transition temperature of 20° C. or lower, an acid value of 5 to 400 equivalent/106 g, and a number average molecular weight of 5,000 to 60,000 and a glass transition temperature of 50. An adhesive composition containing an amorphous polyurethane resin (B) having a temperature of not less than 0° C. and a polyisocyanate (C).

Description

  The present invention relates to an adhesive composition having excellent adhesiveness, coatability, and solvent resistance. More specifically, the present invention relates to a wet film laminated sheet and a polishing pad using the same, and more specifically, a wet film laminated sheet obtained by laminating a urethane porous layer on a polyester film, and obtained by removing the skin layer. The present invention relates to a polishing pad suitable for precision surface polishing of electronic components such as liquid crystal glass, glass discs, photomasks, silicon wafers, and CCD cover glasses.

  Wet film laminated sheets, in which a urethane-like porous film of urethane that has been wet coagulated (hereinafter referred to as wet film) is laminated on a polyester film, have been conventionally used for polishing pads for precision surface polishing of electronic parts. ing.

  Conventionally, a wet film laminated sheet as described above is formed by applying a solution of a polyurethane prepolymer onto a polyester film to form a wet film, and then peeling this film from the polyester film to obtain another polyester film. It was obtained by sticking on top with an adhesive. Further, when forming a polishing pad, the skin layer of this wet film was removed in advance by grinding, polishing or the like to form a surface suede-like film and then adhered onto another polyester film. As described above, once the wet film is peeled from the polyester film and attached to another polyester film with an adhesive, the conventional polyester film and the wet film are poor in mutual adhesiveness, and without adhesive. This is because it could not be used as it was as a polishing pad or the like. However, the above method has a problem that when the wet film is peeled off from the polyester film, the wet film is likely to be deformed and sometimes breaks or cuts occur. Therefore, the type of polyurethane used is limited and the thickness of the wet film is also limited. In addition, the precision of the flatness (surface irregularity) is required for the polishing pad for precision polishing, and in recent years, along with the development of measuring equipment for precision polishing surface, the quality demanded by users is increasing. Higher precision polishing pads are required, but when a wet film is attached to a polyester film using an adhesive as described above, the unevenness of the adhesive causes the wet film surface to affect the flatness. There was also a problem that the accuracy deteriorated.

  There is also provided a wet film laminated sheet that can be obtained without the step of peeling a wet film from a polyester film and then pasting it onto another polyester film, and can achieve high accuracy when used as a polishing pad (for example, Patent Reference 1).

Japanese Patent No. 3723897

  However, in the above-mentioned method, there is a problem that the base material film is limited, and it is necessary to re-stretch and heat-fix after applying the easily-adhesive aqueous coating liquid.

  The present invention is an adhesive composition which is excellent in adhesiveness, coatability, and solvent resistance for favorably adhering a urethane porous layer and a substrate film. The adhesive composition of the present invention, regardless of the substrate film, a wet film laminated sheet and a polishing pad without the step of once peeling the wet film from the polyester film as described above and attaching it to another polyester film. Obtainable.

  As a result of intensive studies, the present inventors have found that the above-mentioned problems can be solved by the means described below, and arrived at the present invention. That is, the present invention has the following configurations.

Amorphous polyester resin (A) having a number average molecular weight of 5,000 to 40,000, a glass transition temperature of 20° C. or lower, an acid value of 5 to 400 equivalent/10 ⁶ g, and a number average molecular weight of 5,000 to 60,000, glass transition temperature. An adhesive composition containing an amorphous polyurethane resin (B) having a temperature of 50° C. or higher and a polyisocyanate (C).

  The amorphous polyester resin (A) preferably has two or more carboxyl groups at the resin end, and the blending ratio of the amorphous polyester resin (A) and the amorphous polyurethane resin (B) is The amorphous polyurethane resin (B) is preferably 5 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the crystalline polyester resin (A).

  A laminate in which an adhesive layer made of the adhesive composition and a plastic film are laminated. Further, a laminate in which a resin is laminated on the surface of the adhesive layer. A polishing pad comprising a polishing layer on a part of the laminate.

  The adhesive composition of the present invention has excellent adhesiveness between the urethane porous layer and the base film, and also has excellent coatability and solvent resistance. Further, the adhesive composition of the present invention can obtain a wet film laminated sheet and a polishing pad without selecting a base material film, without once removing the wet film from the polyester film and attaching it to another polyester film. You can

<Amorphous polyester resin (A)>
The amorphous polyester resin (A) used in the present invention is preferably a polyester having a polyvalent carboxylic acid component and a polyhydric alcohol component as copolymerization components, and has a dicarboxylic acid component and a glycol component as copolymerization components. Is more preferable.

  The dicarboxylic acid component constituting the amorphous polyester resin (A) is not particularly limited, but includes an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid or an alicyclic dicarboxylic acid, particularly an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid. It is preferable to use an acid together.

  The amount of the aromatic dicarboxylic acid copolymerized is preferably 50 mol% or more, more preferably 60 mol% or more, when the total amount of carboxylic acid components is 100 mol %. If it is too small, the resistance to moist heat may decrease. Moreover, 90 mol% or less is preferable, and 80 mol% or less is more preferable. If the amount is too large, the adhesion to the substrate may decrease.

  Specific examples of the aromatic dicarboxylic acid are not particularly limited, but terephthalic acid, isophthalic acid, orthophthalic acid, 1,5-naphthalic acid, 2,6-naphthalic acid, 4,4′-diphenyldicarboxylic acid, 2,2 Examples thereof include'-diphenyldicarboxylic acid and 4,4'-diphenyletherdicarboxylic acid, which can be used alone or in combination of two or more kinds. Of these, the use of terephthalic acid and isophthalic acid is particularly preferable from the viewpoint of resistance to moist heat.

  The aliphatic dicarboxylic acid is not particularly limited, but it is preferable to use an aliphatic dicarboxylic acid having 4 to 18 carbon atoms. The aliphatic dicarboxylic acid preferably has 5 or more carbon atoms, and more preferably 6 or more carbon atoms. Further, the number of carbon atoms is preferably 10 or less. The copolymerization amount of the aliphatic dicarboxylic acid is preferably 50 mol% or less, more preferably 40 mol% or less, when the total amount of carboxylic acid components is 100 mol%. If it is too large, the resistance to moist heat may decrease. Further, it is preferably 10 mol% or more, more preferably 20 mol% or more. If the amount is too small, the adhesion to the substrate may decrease.

  Specific examples of the aliphatic dicarboxylic acid include, but are not limited to, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, octadecanedioic acid and the like, and these may be used alone or in combination of two or more. You can Of these, adipic acid and sebacic acid are particularly preferable from the viewpoint of availability.

  The copolymerization amount of the alicyclic dicarboxylic acid is preferably 50 mol% or less, more preferably 40 mol% or less, further preferably 30 mol% or less, when the total amount of carboxylic acid components is 100 mol%. %, particularly preferably 20 mol% or less, most preferably 10 mol% or less, and 0 mol% is also acceptable. If the amount is too large, it may not be possible to obtain a polyester resin having excellent resistance to moist heat. Specific examples of the alicyclic dicarboxylic acid are not particularly limited, but are 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4-methyl-1,2-cyclohexanedicarboxylic acid. Examples thereof include acids and dimer acids, which may be used alone or in combination of two or more. It is particularly preferable to use 1,4-cyclohexanedicarboxylic acid among them from the viewpoint of availability.

  For the amorphous polyester resin (A), it is preferable to use a polycarboxylic acid anhydride for the purpose of imparting an acid value or branching. It is more preferably a trivalent or higher polycarboxylic anhydride. By imparting an acid value or branching, it is expected that the reactivity with the polyisocyanate (C) is improved and the adhesiveness to the base film is improved. The polycarboxylic acid anhydride is not particularly limited, but aromatic anhydrides such as phthalic anhydride, pyromellitic anhydride, trimellitic anhydride, ethylene glycol bis(anhydrotrimellitate), and glycerol trisanhydrotrimellitate. Polycarboxylic acid; Aliphatic polycarboxylic acid such as fumaric anhydride, maleic anhydride, succinic anhydride, itaconic anhydride, dodecenyl succinic anhydride; hexahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, etc. An alicyclic anhydride polyvalent carboxylic acid can be mentioned. These can be used alone or in combination of two or more.

  Among the above-mentioned polycarboxylic acid anhydrides, aromatic polycarboxylic acid anhydrides are preferred because they have higher acid value and branching effect than those of aliphatic polycarboxylic acid anhydrides and polycarboxylic acid alicyclic anhydrides. Of these, trimellitic anhydride, ethylene glycol bis(anhydrotrimellitate) and glycerol trisanhydrotrimellitate are preferable, and trimellitic anhydride is more preferable from the viewpoint of availability.

  The method of imparting branching is not particularly limited, but dehydration esterification is carried out with other polyvalent carboxylic acids or polyhydric alcohols by using a trifunctional or higher functional polycarboxylic anhydride as a copolymerization component of the amorphous polyester resin (A). There is a method of polymerizing through steps. The copolymerization amount of the polycarboxylic acid anhydride is preferably 0.1 mol% or more, more preferably 0, when the total amount of the carboxylic acid components of the amorphous polyester resin (A) is 100 mol %. It is 0.5 mol% or more. If the amount is too small, branching may be insufficient. Further, it is preferably 5 mol% or less, more preferably 2 mol% or less, still more preferably 1 mol% or less. If it is too large, the mechanical properties of the thin film may deteriorate, and gelation may occur during polymerization.

  The method of imparting an acid value is not particularly limited, but after polymerizing a polyester resin (prepolymer) with a dicarboxylic acid component and a glycol component, subsequently, a trifunctional or more polyvalent anhydrous carboxylic acid is added to the system to obtain an acid value. The method of giving is mentioned. The copolymerization amount of the polycarboxylic acid anhydride is preferably 0.1 mol% or more, more preferably 0.5 mol, based on 100 mol% of the total amount of the carboxylic acid component of the polyester resin (prepolymer). % Or more. If it is too small, the acid value may become insufficient. Further, it is preferably 5 mol% or less, more preferably 2 mol% or less, still more preferably 1 mol% or less. If it is too large, the mechanical properties of the thin film may deteriorate, and gelation may occur during polymerization.

The acid value of the amorphous polyester resin (A) may be 5 equivalents/10 ⁶ g or more, preferably 10 equivalents/10 ⁶ g or more, and more preferably 15 equivalents/10 ⁶ g or more. preferable. If the amount is too small, the reactivity with the polyisocyanate (C) decreases, and the adhesiveness may decrease. On the other hand, it is necessary that the amount is 400 equivalents/10 ⁶ g or less, preferably 200 equivalents/10 ⁶ g or less, more preferably 150 equivalents/10 ⁶ g or less, and 130 equivalents/10 ⁶ g. The following is more preferable. If it is too large, hydrolysis tends to occur.

  The amorphous polyester resin (A) preferably has two or more carboxyl groups at the terminal of the resin. By having two or more carboxyl groups at the end of the amorphous polyester resin (A), it is possible to improve the reactivity with the polyisocyanate (C) as compared with the case of having one carboxyl group, and excellent adhesion Can develop sex.

  The polyhydric alcohol component constituting the amorphous polyester resin (A) used in the present invention is not particularly limited, but includes an aliphatic glycol, an aromatic glycol or an alicyclic glycol, and the aliphatic glycol is particularly used. Preferably.

  The aliphatic glycol may be either a linear aliphatic glycol or a branched aliphatic glycol. The aliphatic glycol is not particularly limited, but a glycol having 2 to 12 carbon atoms is preferable. The more preferred carbon number of the aliphatic glycol is 3 or more. A carbon number of 9 or less is preferable, a carbon number of 8 or less is more preferable, a carbon number of 7 or less is further preferable, and a carbon number of 6 or less is particularly preferable. The copolymerization amount of the aliphatic glycol is preferably 40 mol% or more, more preferably 50 mol% or more, still more preferably 60 mol% or more, when the total amount of the polyhydric alcohol component is 100 mol%. , More preferably 70 mol% or more, particularly preferably 80 mol% or more, most preferably 90 mol% or more, and even 100 mol%. If the amount is too small, the adhesion to a polyethylene terephthalate film (hereinafter, also referred to as PET film) may decrease.

  Specific examples of the aliphatic glycol are not particularly limited, but ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,2-butanediol, 2-methyl-1. , 3-propane diol, neopentyl glycol, methyl pentane diol, pentane diol, hexane diol, heptane diol, octane diol, nonane diol, decane diol, dodecane diol and the like. These may be used alone or in combination of two or more. Can be used. Of these, ethylene glycol, neopentyl glycol, 1,4-butanediol, and 2-methyl-1,3-propanediol are particularly preferable.

  The alicyclic glycol is not particularly limited, but examples thereof include cyclohexanediol, cyclohexanedimethanol, hydrogenated xylylene glycol and the like. The aromatic glycol is not particularly limited, but examples thereof include xylylene glycol.

  The glass transition temperature (hereinafter, also referred to as Tg) of the amorphous polyester resin (A) needs to be 20° C. or lower. The glass transition temperature is preferably 14° C. or lower, more preferably 13° C. or lower, still more preferably 12° C. or lower. If the glass transition temperature is too high, the adhesiveness may decrease. The lower limit is not particularly limited, but is preferably -10°C or higher, and more preferably -5°C or higher.

  The glass transition temperature in the present invention is measured by a differential scanning calorimeter (SII, DSC-200). Specifically, about 5 mg of a sample (sample) is placed in an aluminum pressing lid type container, sealed, cooled to −50° C. using liquid nitrogen, and then heated to 150° C. at 20° C./min. In the endothermic curve obtained in the process, the temperature at the intersection of the baseline before the endothermic peak appears and the tangent line toward the endothermic peak is taken as the glass transition temperature (Tg, unit: °C).

  The number average molecular weight of the amorphous polyester resin (A) needs to be 5,000 or more, preferably 6,000 or more, more preferably 7,000 or more, further preferably 8,000 or more, and 10,000. The above is particularly preferable. Further, it is necessary to be 40,000 or less, preferably 35,000 or less, more preferably 30,000 or less, and particularly preferably 25,000 or less. When the number average molecular weight is lower than 5,000, mechanical properties as an adhesive are insufficient, and sufficient adhesiveness to a substrate such as a polyethylene terephthalate film (hereinafter also referred to as PET film), processability, and moist heat resistance can be obtained. Sometimes there is not. When the number average molecular weight is higher than 40,000, when the adhesive is used by dissolving it in a solvent, the solution viscosity may become too high, which may cause a problem that it cannot be actually used.

  The polyester resin (A) used in the present invention is an amorphous polyester resin. Being amorphous, it can be more stably dissolved in various organic solvents as compared with crystallinity. Further, it is advantageous in that after the adhesive composition is applied to the substrate, the polyester resin does not crystallize and the adhesive strength is not lowered due to the volume shrinkage. The term “amorphous” in the present invention means that the temperature is raised from −100° C. to 300° C. at 20° C./min using a differential scanning calorimeter (DSC), and then the temperature is lowered to −100° C. at 50° C./min. Then, the temperature is raised from −100° C. to 300° C. at 20° C./min. It refers to those that show no melting peaks in both heating processes. On the contrary, the crystallinity refers to the one showing a clear melting peak in either temperature rising process.

<Amorphous polyurethane resin (B)>
The amorphous polyurethane resin (B) used in the present invention preferably comprises a diol component and a diisocyanate component as copolymerization components. Further, if necessary, for example, a diamine component may be copolymerized without any problem. It is desirable that the diol component contains polyester polyol as the main component (50% by mass or more). It is also possible to use acrylic polyol, polyether polyol, or the like as the main component.

  As the polyester polyol, the amorphous polyester resin (A) can be used. Examples of the acid component of the polyester polyol include the aromatic dicarboxylic acid, aliphatic dicarboxylic acid and alicyclic dicarboxylic acid exemplified in the amorphous polyester resin (A). Of these, aromatic dicarboxylic acids are preferably used, and terephthalic acid and/or isophthalic acid are more preferable.

  The copolymerization amount of the aromatic dicarboxylic acid is preferably 70 mol% or more, more preferably 80 mol% or more, further preferably 90 mol% or more, when the total amount of carboxylic acid components is 100 mol%. It is particularly preferably 95 mol% or more, and 100 mol% may be used. If it is too small, the resistance to moist heat may decrease.

  Examples of the glycol component of the polyester polyol include the aliphatic glycol, aromatic glycol, and alicyclic glycol exemplified in the amorphous polyester resin (A). Of these, aliphatic glycols are preferably used, and ethylene glycol and/or neopentyl glycol are more preferable.

  The copolymerization amount of the aliphatic glycol is preferably 70 mol% or more, more preferably 80 mol% or more, further preferably 90 mol% or more, when the total amount of the polyhydric alcohol component is 100 mol%. It is particularly preferably 95 mol% or more, and 100 mol% may be used.

  There is no problem even if the diol component contains a low molecular weight component other than the polyester polyol, if necessary. For example, the diol compound may be 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 2,3-butylene glycol, 2-methyl-1,3-propanediol, 2,2-dimethyl. -1,3-propanediol (neopentyl glycol), 3-methyl-1,5-pentanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1,3-hexanediol, 2,2-Dimethyl-3-hydroxypropyl-2',2'-dimethyl-3-hydroxypropanate, 2-normal butyl-2-ethyl-1,3-propanediol, 3-ethyl-1,5-pentane Diol, 3-propyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol, 3-octyl-1,5-pentanediol, 3-phenyl-1,5-pentanediol, 2, 5-dimethyl-3-sodium sulfo-2,5-hexanediol etc. are mentioned. 1,2-propanediamine, 1,5-pentamethylenediamine, 1,3-bis(aminomethyl)cyclohexane, 1,2-diaminocyclobutane, 1,2-diaminocyclopentane, 1,2-diaminocyclo It is also possible to use a diamine compound such as heptane. These low molecular weight components may be used alone or in combination of two or more. Of these, neopentyl glycol is preferred.

  As the diol component, the polyester polyol content is preferably 50% by mass or more, more preferably 60% by mass or more, and further preferably 70% by mass or more. If the amount is too small, the urethane group concentration becomes high and the cohesive force increases, which may result in poor adhesion to the substrate. Further, it is preferably 99% by mass or less, and more preferably 98% by mass or less. If the amount is too large, the urethane group concentration becomes low, the cohesive force is lowered, and the adhesive strength may be lowered.

  When the amorphous polyester resin (A) is used as the diol component, it is preferable that it is not acid-added with a polycarboxylic anhydride. When acid-added, the resin end has a carboxylic acid group, and the reactivity with the diisocyanate component may decrease.

  The diisocyanate component used in the amorphous polyurethane resin (B) is not particularly limited, and examples thereof include an aromatic diisocyanate component, an aliphatic diisocyanate component or an alicyclic diisocyanate component. As the aromatic diisocyanate component, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p-phenylene diisocyanate, diphenylmethane diisocyanate, m-phenylene diisocyanate, 3,3′-dimethoxy-4,4′-biphenylene diisocyanate , 1,5-naphthalene diisocyanate, 2,6-naphthalene diisocyanate, 4,4′-diisocyanate diphenyl ether, 1,5-xylylene diisocyanate, or o-tolidine diisocyanate. Examples of the aliphatic diisocyanate component include ethylene diisocyanate, propylene diisocyanate, hexamethylene diisocyanate, tetramethylene diisocyanate, and 3,3'-dimethylbiphenyl-4,4'-diisocyanate. Examples of the alicyclic diisocyanate include 1,3-diisocyanate methylcyclohexane, 1,4-diisocyanate methylcyclohexane and isophorone diisocyanate. These may be used alone or in combination of two or more. Among them, the aromatic diisocyanate component is preferable, and diphenylmethane diisocyanate is more preferable.

  The number average molecular weight of the amorphous polyurethane resin (B) is required to be 5,000 or more, preferably 6,000 or more, more preferably 7,000 or more, further preferably 8,000 or more, It is particularly preferably at least 10,000. Further, it is necessary to be 60000 or less, and preferably 50000 or less. When the number average molecular weight is lower than 5,000, the mechanical properties as an adhesive are insufficient, and sufficient adhesiveness to a substrate such as a PET film, workability, and wet heat resistance may not be obtained. When the number average molecular weight is higher than 60,000, when the adhesive is used by dissolving it in a solvent, the viscosity of the solution becomes too high, which may cause a problem that it cannot be actually used.

  The glass transition temperature of the amorphous polyurethane resin (B) needs to be 50° C. or higher. The glass transition temperature is more preferably 60°C or higher, and further preferably 70°C or higher. If the glass transition temperature is too low, blocking may occur. Further, it is preferably 150°C or lower, more preferably 120°C or lower, and further preferably 100°C or lower. If the glass transition temperature is too high, it may not dissolve in the organic solvent.

  The polyurethane resin (B) used in the present invention is an amorphous polyurethane resin. Being amorphous, it can be more stably dissolved in various organic solvents as compared with crystallinity. Further, it is advantageous in that after the adhesive composition is applied to the substrate, the polyurethane resin does not crystallize and the adhesive strength is not lowered due to volume shrinkage. The term “amorphous” in the present invention means that the temperature is raised from −100° C. to 300° C. at 20° C./min using a differential scanning calorimeter (DSC), and then the temperature is lowered to −100° C. at 50° C./min. Then, the temperature is raised from −100° C. to 300° C. at 20° C./min. It refers to those that show no melting peaks in both heating processes. On the contrary, the crystallinity refers to the one showing a clear melting peak in either temperature rising process.

  The amorphous polyurethane resin (B) used in the present invention may have an acid value. Examples of the method of introducing a carboxyl group into the amorphous polyurethane resin (B) used in the present invention include a method of synthesizing an amorphous polyurethane resin by using a polyester polyol having an end modified with an acid, and dimethylolpropionic acid. A method of synthesizing an amorphous polyurethane resin by using dimethylolbutanoic acid or the like as a chain extender is mentioned. Of these, the latter is preferable in order to adjust the molecular weight to an appropriate value during the polymerization of the amorphous polyurethane resin.

  The content of the amorphous polyurethane resin (B) is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and still more preferably 100 parts by mass of the amorphous polyester resin (A). Is 15 parts by mass or more. If it is too small, blocking may occur. Further, it is preferably 70 parts by mass or less, more preferably 45 parts by mass or less, and further preferably 40 parts by mass or less. If it is too large, the adhesiveness may decrease.

<Polyisocyanate (C)>
The polyisocyanate (C) used in the present invention is not particularly limited as long as it has two or more isocyanate groups in the molecule, but from the viewpoint of weather resistance, an aliphatic polyisocyanate or an alicyclic polyisocyanate is preferable, Aliphatic or alicyclic diisocyanates are more preferred. Specific examples of the polyisocyanate (C) are not particularly limited, and examples of the aliphatic polyisocyanate include ethylene diisocyanate, propylene diisocyanate, hexamethylene diisocyanate (hereinafter, also referred to as HDI), tetramethylene diisocyanate, and the like. .. Examples of the alicyclic diisocyanate include 1,3-diisocyanate methylcyclohexane, 1,4-diisocyanate methylcyclohexane, and isophorone diisocyanate. Further, a compound functionalized with these compounds, a compound obtained by modifying the diol compound with the above isocyanate, or the like can be given. It is also possible to use aromatic diisocyanates. As the aromatic diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p-phenylene diisocyanate, diphenylmethane diisocyanate, m-phenylene diisocyanate, 3,3'-dimethoxy-4,4'-biphenylene diisocyanate, 1,5-naphthalene diisocyanate, 2,6-naphthalene diisocyanate, 3,3′-dimethylbiphenyl-4,4′-diisocyanate, 4,4′-diisocyanate diphenyl ether, or 1,5-xylylene diisocyanate may be mentioned. These can be used alone or in combination of two or more. Among them, hexamethylene diisocyanate is preferable as the aliphatic polyisocyanate compound, and isophorone diisocyanate is preferable as the alicyclic polyisocyanate compound.

  The polyisocyanate (C) is preferably 0.5 part by mass or more based on 100 parts by mass of the polyester resin (A). The amount is more preferably 1 part by mass or more, further preferably 1.5 parts by mass or more, and particularly preferably 2 parts by mass or more. Further, it is preferably 20 parts by mass or less, more preferably 19 parts by mass or less, further preferably 18 parts by mass or less, particularly preferably 17 parts by mass or less, and most preferably 16 parts by mass or less. is there. If the amount is too small, it may not be possible to sufficiently react with the amorphous polyester resin (A), and the solvent resistance may decrease. If it is too large, the adhesiveness with the amorphous polyurethane resin (B) may decrease.

<Adhesive composition>
The adhesive composition of the present invention is a composition containing the amorphous polyester resin (A), the amorphous polyurethane resin (B) and the polyisocyanate (C). The adhesive composition may contain a widely used additive as long as the characteristics of the present invention are not impaired. The additive is not particularly limited, and examples thereof include known additives such as an ultraviolet absorber, an antioxidant, a silane coupling agent, a plasticizer, and various adhesive resin components, and these may be used alone or Two or more kinds can be used in combination. Further, a polyester resin different from the amorphous polyester (A) or a polyurethane resin different from the amorphous polyurethane resin (B) may be blended as long as the effects of the present invention are not impaired. Further, a polyolefin resin, a polyimide resin, a polyamide resin, a polyamideimide resin or the like may be blended.

  A curing catalyst may also be used to control the reactivity. The catalyst is not particularly limited, but a polyisocyanate curing catalyst is preferable, and a tin-based or amine-based polyisocyanate curing catalyst is more preferable. Although not particularly limited, specifically, for example, tin such as dibutyltin diacetate, dibutyltin dilaurate, dibutyltin bis bismaleic acid monobutyl ester, dioctyltin bis bismaleic acid monobutyl ester, tetrabutyl diacetoxy distannoxane. System catalysts: tributylamine, triethylenediamine, N'-methyl-N-(2-dimethylaminoethyl)piperazine, 1,8-diazabicyclo(5,4,0)-7-undecene, 1,5-diazabicyclo(4,4) Examples of the amine catalyst include 3,0)-nonene-5,6-dibutylamino-1,8-diazabicyclo(5,4,0)-7-undecene,1,2-dimethylimidazole. Particularly when combined with free polyisocyanate, those obtained by forming a salt of these tertiary amine compounds with phenol or the like are preferable.

  The adhesive composition of the present invention can be made into a varnish by containing an organic solvent. The organic solvent is not particularly limited as long as it can dissolve the amorphous polyester resin (A), the amorphous polyurethane resin (B) and the polyisocyanate (C). Specifically, for example, aromatic hydrocarbons such as benzene, toluene and xylene, aliphatic hydrocarbons such as hexane, heptane, octane and decane, cycloaliphatic hydrocarbons such as cyclohexane, cyclohexene, methylcyclohexane and ethylcyclohexane. Aprotic polar solvents such as hydrogen, N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), methanol, ethanol. Alcohol solvents such as isopropyl alcohol, butanol, pentanol, hexanol, propanediol and phenol, ketone solvents such as acetone, methyl isobutyl ketone, methyl ethyl ketone pentanone, hexanone, cyclohexanone, isophorone, acetophenone, methyl acetate, ethyl acetate, Ester solvents such as butyl acetate, methyl propionate, and butyl formate can be used, and one or more of these can be used in combination. In particular, it is preferable to partially include an aprotic polar solvent from the viewpoint of resin solubility. By including the aprotic polar solvent, the resins are easily mixed in the solvent, and the compatibility is increased, so that the coating film is less likely to have streaks. Particularly, N,N-dimethylformamide (DMF) is preferable.

  The organic solvent is preferably 50 parts by mass or more, more preferably 80 parts by mass or more, and further preferably 100 parts by mass or more, with respect to 100 parts by mass of the amorphous polyester resin (A). If it is too small, it may be difficult to apply it to the substrate. Further, it is preferably 1000 parts by mass or less, more preferably 900 parts by mass or less, and further preferably 800 parts by mass or less. If it is too large, it may be disadvantageous in terms of manufacturing cost and transportation cost. Further, it is preferable that a part of the organic solvent contains an aprotic polar solvent, and is 10 parts by mass or more, and more preferably 15 parts by mass with respect to 100 parts by mass of the amorphous polyester resin (A). More than a part. Further, it is preferably 100 parts by mass or less, and more preferably 70 parts by mass or less.

<Adhesive layer>
An adhesive layer can be prepared using the adhesive composition according to the present invention. The adhesive layer of the present invention refers to a layer of the adhesive composition after the adhesive composition is applied to a substrate, dried, and aged to be cured. The thickness of the adhesive layer is preferably 4 μm or more, more preferably 5 μm or more. If it is too thin, the effect as an adhesive may not be exhibited. Further, it is preferably 30 μm or less, more preferably 25 μm or less.

<Laminate>
The laminate of the present invention is a laminate of two layers of the adhesive layer and the base material 1 (base material 1/adhesive layer), or a laminate of three layers in which the base material 2 is attached to the surface of the adhesive layer. Body (base material 1/adhesive layer/base material 2), and a laminated body in which a laminate of two layers is attached to a laminate of three layers (base material 1/adhesive layer/base material 2/adhesive layer/ The base material 3).

  The base material 1, the base material 2 and the base material 3 that can be used in the present invention include, but are not particularly limited to, metal, plastic, wood, cloth or papers. The metal material is not particularly limited, but various metals such as aluminum, SUS, copper, iron, and zinc, and their respective alloys, metal plates such as plated products, metal foils, vapor deposition layers, and the like can be illustrated. The plastic is not particularly limited, and examples thereof include plastic sheets or films of polyvinyl chloride, polyester, polyolefin, polyamide, poval, polyurethane, or the like. The cloth is not particularly limited, and examples thereof include cotton, silk, hemp, and synthetic fibers such as polyester. The papers are not particularly limited, and examples include high-quality paper, kraft paper, roll paper, glassine paper, and the like. The base material 1, the base material 2 and the base material 3 may be of the same type or may be of different types. Also, a plurality of base materials selected from these may be laminated.

  The adhesive composition of the present invention is particularly suitable for use as a polishing pad. In the case of use as a polishing pad, the substrate 1 is preferably a plastic film, more preferably a polyester film. For the polishing pad, a polyester film is coated with the adhesive composition, dried, and cured by aging or the like to prepare a laminate. Next, a polyurethane prepolymer solution is applied to the surface of the adhesive layer of the laminate, and then wet coagulation and drying (wet film formation) are performed to form a polishing pad (polyester film) having a porous urethane polishing layer on the polyester film. /Adhesive layer/Porous urethane polishing layer) can be prepared.

  Hereinafter, examples will be given in order to describe the present invention in more detail, but the present invention is not limited to the examples. In the examples, "parts" means "parts by mass".

<Production Example (a-1) of Polyester Resin (A)>
49.8 parts of terephthalic acid, 49.8 parts of isophthalic acid, 58.4 parts of adipic acid, 35.4 parts of ethylene glycol, neopentyl glycol were placed in a reaction vessel equipped with a thermometer, a stirrer, a reflux condenser and a distillation tube. 69.3 parts, 1,4-butanediol 60.0 parts, tetra-n-butyl titanate as a catalyst (hereinafter sometimes abbreviated as TBT) 0.03 mol% based on all acid components, 160 The transesterification reaction was carried out while heating from 4°C to 240°C over 4 hours. Then, the pressure in the system was gradually reduced to 5 mmHg over 20 minutes, and a polycondensation reaction was performed at 260° C. for 90 minutes under a vacuum of 0.3 mmHg or less. The mixture was cooled to 220° C. under a nitrogen stream, 2 parts of trimellitic anhydride was added, and the mixture was reacted for 30 minutes to obtain a polyester resin (a-1). The results of the obtained polyester resin (a-1) are shown in Table 1.

<Production Example of Polyester Resins (a-2) to (a-11)>
Polyester resins (a-2) to (a-11) were produced according to the production example of the polyester resin (a-1) except that the type of raw material and the compounding ratio were changed. The results are shown in Table 1. A resin having a number average molecular weight of 50,000 could not be produced because it gelled during the production.

1. Composition of Polyester Resin (A) The composition and composition ratio of the polyester resin (A) were determined by ¹ H-NMR measurement (proton nuclear magnetic resonance spectroscopy) at a resonance frequency of 400 MHz. As a measuring apparatus, 1H-NMR apparatus 400-MR manufactured by VARIAN was used, and deuterated chloroform was used as a solvent.

2. Glass transition temperature (Tg)
It was measured by a differential scanning calorimeter (DSC-200, manufactured by SII). As a sample, 5 mg of a sample (polyester resin or polyurethane resin) was placed in an aluminum pressing lid type container and hermetically sealed. First, the sample was cooled to −50° C. using liquid nitrogen, and then heated to 150° C. at 20° C./minute. In the endothermic curve obtained in this process, the temperature at the intersection of the baseline before the endothermic peak and the tangent line toward the endothermic peak was taken as the glass transition temperature (Tg, unit: °C).

3. Acid value (AV)
0.2 g of a sample (polyester resin or polyurethane resin) was precisely weighed, dissolved in 40 ml of chloroform, and titrated with an ethanol solution of 0.01-N potassium hydroxide. Phenolphthalein was used as the indicator. The measured value was converted to the equivalent weight per 10 ⁶ g of the sample, and the unit was equivalent weight/10 ⁶ g.

4. Number average molecular weight (Mn)
A sample (polyester resin or polyurethane resin) dissolved or diluted in tetrahydrofuran so that the resin concentration is about 0.5%, and filtered through a membrane filter made of polytetrafluoroethylene having a pore size of 0.5 μm for measurement. And The molecular weight of the measurement sample was measured by gel permeation chromatography using tetrahydrofuran as a mobile phase and a differential refractometer as a detector. The flow rate was 1 mL/min and the column temperature was 30°C. Showa Denko KF-802, 804L, and 806L were used for the column. Monodisperse polystyrene was used as the molecular weight standard. However, when the measurement sample was not dissolved in tetrahydrofuran, N,N-dimethylformamide was used instead of tetrahydrofuran. Low molecular weight compounds having a number average molecular weight of less than 1000 (such as oligomers) were omitted without counting.

In Table 1, the copolymerization components of the polyester resin are represented by the following abbreviations.
TPA: terephthalic acid residue IPA: isophthalic acid residue AA: adipic acid residue SA: sebacic acid residue TMA: trimellitic acid residue EG: ethylene glycol residue 2MG: 2-methyl-1,3-propanediol residue Group NPG: neopentyl glycol residue BD: 1,4-butanediol residue

<Synthesis Example (b-1) of Amorphous Polyurethane Resin (B)>
In a reaction can equipped with a stirrer, a thermometer and a Dimroth, polyester polyol (composition terephthalic acid/isophthalic acid//ethylene glycol/neopentyl glycol=50/50//50/50 molar ratio, number average molecular weight 2000, glass 220 parts of transition temperature 55° C.) and 200 parts of toluene were charged, the temperature was raised to 80° C., and they were completely dissolved in 1 hour. Then, 150 parts of methyl ethyl ketone, 8 parts of neopentyl glycol, 3 parts of 1,6-hexanediol, and 50 parts of 4,4′-diphenylmethane diisocyanate were charged, and the mixture was stirred at 80° C. for 1 hour. After that, 0.1 g of dibutyltin dilaurate was charged and stirred at 80° C. for 10 hours to carry out a urethanization reaction. After completion of the reaction, toluene and methyl ethyl ketone were charged and diluted to obtain a solution of the target amorphous polyurethane resin (B) having a solid content concentration of 32% by mass. The amorphous polyurethane resin (B) thus obtained had a number average molecular weight of 26000, a glass transition temperature of 80° C., and an acid value of 1 equivalent/10 ⁶ g or less.

<Synthesis Example (b-2) of Amorphous Polyurethane Resin (B)>
In a reaction can equipped with a stirrer, a thermometer, and a Dimroth, polyester polyol (composition terephthalic acid/isophthalic acid//ethylene glycol/sebacic acid/neopentyl glycol=50/45/5//50/50 molar ratio, number 220 parts of an average molecular weight of 2,000 and a glass transition temperature of 55° C.) and 200 parts of toluene were charged, the temperature was raised to 80° C., and they were completely dissolved in 1 hour. Then, 150 parts of methyl ethyl ketone, 8 parts of neopentyl glycol, 3 parts of 1,6-hexanediol and 50 parts of 4,4′-diphenylmethane diisocyanate were charged, and the mixture was stirred at 80° C. for 1 hour. After that, 0.1 g of dibutyltin dilaurate was charged and stirred at 80° C. for 10 hours to carry out a urethanization reaction. After completion of the reaction, toluene and methyl ethyl ketone were charged and diluted to obtain a solution of the target amorphous polyurethane resin (B) having a solid content concentration of 32% by mass. The amorphous polyurethane resin (B) thus obtained had characteristic values of a number average molecular weight of 42,000, a glass transition temperature of 60° C. and an acid value of 1 equivalent/106 g or less.

<Example 1>
70 parts of amorphous polyester resin (a-1), 20 parts of methyl ethyl ketone, and 20 parts of toluene were charged and dissolved in a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser. Then, 125 parts of amorphous polyurethane resin (b-1) solution (30 parts of solid) and 25 parts of DMF were charged and dissolved. 1 part of polyisocyanate (c-1) was added to this solution to obtain an adhesive composition 1. The results are shown in Table 2.

<Examples 2 to 11, Comparative Examples 1 to 5>
Adhesive compositions 2 to 16 were prepared according to Example 1 except that the kinds of raw materials and the compounding ratio were changed.
In Tables 2 and 3, the following polyisocyanates (C) were used.
Polyisocyanate (c-1): HDI isocyanurate body "Coronate (registered trademark) HX manufactured by Nippon Polyurethane"
Polyisocyanate (c-2): HDI adduct "Coronate (registered trademark) HL made by Nippon Polyurethane"

5. Evaluation of coatability The adhesive composition was applied to a PET film having a thickness of 50 μm by an applicator so that the film thickness after drying was 25 μm. It was confirmed whether streaks were generated when the adhesive composition was applied with an applicator.
Evaluation criteria ○: No streaks △: Light streaks ×: Streaks

6. Blocking resistance A 50 μm-thick PET film was coated with the adhesive composition so that the film thickness after drying was 25 μm, and dried at about 120° C. for about 1 minute to prepare a test sample. Two test samples were prepared, the adhesive layers were overlapped with each other, and pressed at 40° C. and 30 MPa for 5 minutes, and then the presence or absence of blocking was confirmed.
Evaluation criteria ○: No blocking ×: Blocking

7. Solvent resistance A PET film having a thickness of 50 μm was coated with the adhesive composition so that the film thickness after drying was 25 μm. Then, it was dried at about 120° C. for about 1 minute to volatilize the solvent. After that, aging was performed at 40° C. for 3 days. A urethane prepolymer solution prepared in advance was applied onto the adhesive layer to form a wet film. The cross section was cut out and visually confirmed for peeling. The urethane prepolymer solution is a DMF solution of a urethane prepolymer containing polybutylene adipate diol/diphenylmethane-4,4′-diisocyanate/diethylene glycol as a copolymerization component.
Evaluation criteria ○: No peeling △: Partially peeling ×: All peeling

8. Adhesive Strength A PET film having a thickness of 50 μm was coated with the adhesive composition so that the film thickness after drying was 25 μm. Then, it was dried at about 120° C. for about 1 minute to volatilize the solvent. After that, aging was performed at 40° C. for 3 days. A urethane prepolymer solution prepared in advance was laminated on the adhesive layer by wet film formation so that the film thickness after drying was 25 μm. At this time, a partial stripping margin was prepared. Then, the adhesive strength was measured. Those having a strength of 1 kgf/inch or more have good adhesive strength.

Claims (6)

Amorphous polyester resin (A) having a number average molecular weight of 5,000 to 40,000, a glass transition temperature of 20° C. or lower, an acid value of 5 to 400 equivalent/10 ⁶ g, and a number average molecular weight of 5,000 to 60,000, glass transition temperature. An adhesive composition containing an amorphous polyurethane resin (B) having a temperature of 50° C. or higher and a polyisocyanate (C).   The adhesive composition according to claim 1, wherein the amorphous polyester resin (A) has two or more carboxyl groups at the resin end.   The mixing ratio of the amorphous polyester resin (A) and the amorphous polyurethane resin (B) is 5 parts by mass or more of the amorphous polyurethane resin (B) with respect to 100 parts by mass of the amorphous polyester resin (A). The adhesive composition according to claim 1 or 2, which is less than or equal to parts by mass.   A laminate in which an adhesive layer made of the adhesive composition according to any one of claims 1 to 3 and a plastic film are laminated.   A laminate in which a resin is laminated on the surface of the adhesive layer of the laminate according to claim 4. A polishing pad comprising a polishing layer on a part of the laminate according to claim 5.