KR20160100639A - Polyurethane resin composition and polyurethane mounting pad - Google Patents

Abstract

The present invention relates to a polyurethane resin composition for manufacturing a support pad of a polishing apparatus, and to a polyurethane pad comprising a wet coagulation of the resin composition. More particularly, the polyurethane resin composition comprises: a first polyurethane resin including a residue of a first polyester polyol, a residue of a polyisocyanate compound, and a residue of a chain extender; a second polyurethane resin having a composition different to the first polyurethane resin; an organic solvent; and a surfactant. The residue of the first polyester includes reaction products between polyols including polycarboxylic acid having 2-10 carbon atoms and diethylene glycol. The polyurethane support pad has low hardness, excellent rate of extrusion, and high extrusion elasticity.

Description

POLYURETHANE RESIN COMPOSITION AND POLYURETHANE MOUNTING PAD BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to a polyurethane resin composition and a polyurethane support pad, and more particularly, to a polyurethane resin composition and a polyurethane support pad which can form a long and large pore uniformly in the interior thereof to provide a support pad having low hardness, A resin composition and a polyurethane support pad made from such a resin composition.

Since a substrate used for a semiconductor device or a display device requiring high integration requires a fine and precise surface, various planarization methods have been applied. Particularly, in accordance with the trend of high integration and high performance of semiconductor devices or display devices, a method of relatively moving and polishing a polishing pad and an object to be polished while supplying a slurry composition containing abrasive particles and various chemical components between the polishing pad and the object to be polished Is commonly used. In this polishing method, the object to be polished is fixed on the supporting pad so as to maintain a predetermined position and posture in polishing or processing for more precise polishing.

On the other hand, Japanese Patent Laid-Open No. 2006-334745 discloses a polyurethane foam obtained by reacting and curing polyols, polyisocyanates, a blowing agent, a catalyst and a water repellency-imparting agent, and a polishing support pad obtained using the same. However, the polyurethane foam is obtained by using a foaming agent such as water, methylene chloride or carbonic acid gas. Such a foam has a relatively high hardness, or it is difficult to uniformly form long and large pores therein, Securing a high compression ratio and a compressive elastic modulus in the region is not easy.

Previously, the support pads have different sizes and irregularly distributed pores in the interior, and the cushioning performance and adsorption force of the support pads are not good. Also, since the polished body is not firmly fixed on the support pads during the polishing process, There is a problem that can not be achieved. In addition, since the former support pad exhibits uneven size and distribution of bubbles formed therein, not only the physical properties such as compression ratio and compressive elastic modulus are not good, but also the water repellent function is not sufficient and the abrasive article easily deviates during polishing or processing .

Accordingly, it is necessary to develop a new support pad that enables more precise and efficient polishing of a substrate used in a semiconductor device or a display device.

Japanese Patent Application Laid-Open No. 2006-334745

The present invention is to provide a polyurethane resin composition capable of uniformly forming long and large pores therein to provide a support pad having low hardness, excellent compression ratio and high compression modulus.

Further, the present invention is to provide a polyurethane support pad having a low hardness, an excellent compression ratio and a high compression modulus by uniformly forming long and large pores therein.

The present invention relates to a process for the preparation of a polyurethane foam comprising a first polyester polyol residue comprising a reactant between a polycarboxylic acid having from 2 to 10 carbon atoms and a polyol comprising diethylene glycol, Urethane resin; A residue of a second polyester polyol comprising a reactant between a polycarboxylic acid having 2 to 10 carbon atoms and at least one diol compound selected from the group consisting of ethylene glycol and 1,4-butanediol, a residue of a polyisocyanate compound and a chain extender A second polyurethane resin comprising a moiety; An organic solvent containing at least one selected from the group consisting of dimethylformamide (DMF) and methyl ethyl ketone (MEK); And a surfactant, wherein the content of the residues of the polyisocyanate compound contained in each of the first polyurethane resin and the second polyurethane resin is 20 to 30% by weight, and the polyurethane To provide a resin composition.

The present invention also provides a polyurethane support pad comprising a wet coagulate of said polyurethane resin composition.

Hereinafter, the polyurethane resin composition and the polyurethane support pad according to a specific embodiment of the present invention will be described in more detail.

In the present specification, the term 'support pad' refers to a pad that serves to closely adhere or fix a film to be polished to a carrier in a polishing process during a substrate manufacturing process used in a semiconductor or a display device.

Further, the polyol means an alcohol compound containing two or more hydroxyl groups, and the polycarboxylic acid means a carboxylic acid compound containing two or more carboxyl groups.

According to one embodiment of the invention, the first polyester polyol residue, the polyisocyanate compound residue, and the chain extender residue comprise a reactant between a polycarboxylic acid having from 2 to 10 carbon atoms and a polyol comprising diethylene glycol A first polyurethane resin; A residue of a second polyester polyol comprising a reactant between a polycarboxylic acid having 2 to 10 carbon atoms and at least one diol compound selected from the group consisting of ethylene glycol and 1,4-butanediol, a residue of a polyisocyanate compound and a chain extender A second polyurethane resin comprising a moiety; An organic solvent containing at least one selected from the group consisting of dimethylformamide (DMF) and methyl ethyl ketone (MEK); And a surfactant, wherein the content of the residues of the polyisocyanate compound contained in each of the first polyurethane resin and the second polyurethane resin is 20 to 30% by weight, and the polyurethane A resin composition may be provided.

The present inventors proceeded with studies on the production of support pads using a polyurethane resin and found that a first polyurethane resin synthesized using diethylene glycol as a polyol component and a second polyurethane resin synthesized using other polyol components When the support pad of the polishing apparatus is manufactured by mixing the two kinds of support pads, it is possible to more uniformly include longer and larger pores therein, and air generated between the support substrate and the polishing target film can be easily transferred to the inside, It is possible to uniformly disperse into the region and to exhibit a high compression ratio and a compression recovery ratio while having a low density.

It was difficult to control the shape of the inner pores by controlling the compression ratio or elasticity of the support pad which is finally manufactured by controlling the composition of the polyurethane resin or the content of the reactive material. It is difficult to secure sufficient cushion performance and adsorption force for the object to be polished or the object to be polished can not be firmly fixed on the support pad during the polishing process, so that the precision polishing can not be performed.

On the other hand, the above-mentioned polyurethane resin composition contains a mixture of a first polyurethane resin synthesized using diethylene glycol as a polyol component and a second polyurethane resin synthesized using another kind of polyol component, It is possible to uniformly distribute a plurality of pores having a long shape in the longitudinal direction of the supporting pads and to make the supporting pads have more improved physical properties.

In this specification, the terms 'first' and 'second' are used to distinguish the kind of the polyurethane resin, and the term does not limit the order or importance, and the term " , A third polyurethane resin or a fourth polyurethane resin, etc.).

The support pad made of the polyurethane resin composition may be distinguished from other conventional polyurethane sheets, for example, a polyurethane polishing pad or a polyurethane synthetic leather. Specifically, the polyurethane polishing pad must have a high abrasion resistance and high hardness, and a polyurethane resin having a crosslinking reaction should be used. In addition, the manufacturing method is not a wet solidification process, but a prepolymer and other monomers are mixed in situ, ) And then curing it.

The first polyurethane resin may be obtained by reacting other components together with the first polyester polyol, the polyisocyanate compound and the chain extender. Accordingly, the first polyurethane resin may comprise a residue of a first polyester polyol comprising a reactant between a polycarboxylic acid having 2 to 10 carbon atoms and a polyol comprising diethylene glycol, a residue of a polyisocyanate compound and a residue of a chain extender . ≪ / RTI >

The second polyurethane resin can be obtained by reacting the second polyester polyol, the polyisocyanate compound and the chain extender, optionally together with other components. Accordingly, the second polyurethane resin is a residue of a second polyester polyol comprising a reactant between a polycarboxylic acid having 2 to 10 carbon atoms and at least one diol compound selected from the group consisting of ethylene glycol and 1,4-butanediol, A residue of a polyisocyanate compound and a residue of a chain extender.

As used herein, the term " residue " refers to a certain moiety or unit derived from the specific compound that is included in the result of the chemical reaction when the particular compound participates in the chemical reaction. For example, a residue of a polycarboxylic acid, a residue of an ethylene glycol, and a residue of a butanediol, respectively, each refer to a portion derived from a polycarboxylic acid, ethylene glycol, and butanediol.

On the other hand, the content of the residues of the polyisocyanate compound contained in each of the first polyurethane resin and the second polyurethane resin may be 20 to 30% by weight. If the content of the residues of the polyisocyanate compound contained in each of the first polyurethane resin and the second polyurethane resin is too low, the pore inner wall may collapse during the production of the support pad, and the thickness of the support pad itself may not be easily secured If the content is too large, the strength of the polyurethane resin is greatly increased, so that the compressibility or compressive elastic modulus of the support pad manufactured using the polyurethane resin can be significantly lowered and the hardness of the support pad can be increased.

The first polyurethane resin and the second polyurethane resin may be different from each other in the content of the polyester polyol used in the synthesis process, and may differ in the content of the residue of the polyisocyanate compound contained in each of the first and second polyurethane resins. As described above, by using the first polyurethane resin and the second polyurethane resin in which the residues of the polyisocyanate compound are different from each other, it is possible to uniformly distribute a plurality of pores having a long shape in the longitudinal direction of the finally- It is possible to prevent the phenomenon that the pores are collapsed or the thickness of the support pad becomes thin or uneven in the manufacturing process, and the support pad can have excellent physical properties such as a high compression ratio and a compression recovery ratio.

Specifically, the first polyurethane resin may comprise from 20 to 24% by weight of the residue of the polyisocyanate compound, and the second polyurethane resin may comprise from 25 to 30% by weight of the residue of the polyisocyanate compound.

Also, the first polyurethane resin may comprise from 25 to 30 wt% of the residue of the polyisocyanate compound, and the second polyurethane resin may comprise from 20 to 24 wt% of the residue of the polyisocyanate compound.

The polyurethane resin composition may contain the first polyurethane resin and the second polyurethane resin in a weight ratio of 2: 8 to 6: 4, preferably 3: 7 to 5: 5.

The polyol used in the synthesis of the first polyester polyol may include diethylene glycol. In addition, the polyol used in the synthesis of the first polyester polyol may include diethylene glycol as well as other diols. The other polyol may include at least one diol compound selected from the group consisting of ethylene glycol and 1,4-butanediol. The polyol used in the synthesis of the first polyester polyol may include 10 mol% to 100 mol% of diethylene glycol; And other polyols in residual amounts.

If the content of diethylene glycol in the polyol used for synthesizing the polyester polyol is less than 10 mol%, the pores formed in the support pad may be difficult to have a long shape in the longitudinal direction and the pore size may be uneven , It may be difficult to improve the physical properties of the support pad beyond a certain level.

The polyol used in the synthesis of the second polyester polyol may include at least one diol compound selected from the group consisting of ethylene glycol and 1,4-butanediol. The polyol may further include a diol compound other than ethylene glycol and 1,4-butanediol.

The polycarboxylic acid having 2 to 10 carbon atoms used for synthesis of the first polyester polyol and the second polyester polyol may be a dicarboxylic acid having 4 to 8 carbon atoms and preferably an adipic acid have.

The ratio of the number of moles of the hydroxyl group (-OH) contained in the first polyester polyol (or the second polyester polyol) and the chain extender and the number of moles of the isocyanate group of the polyisocyanate compound is 1: 0.99 to 1: 1.2 , Preferably from 1: 1 to 1: 1.1.

When the molar number of the polyisocyanate compound is smaller than the sum of the number of moles of the hydroxyl group (-OH) contained in the first polyester polyol (or the second polyester polyol) and the chain extender, the polyurethane resin to be produced has an appropriate density , Viscosity and weight-average molecular weight, it is difficult to increase the thickness of the support pad produced using such a polyurethane resin, and physical properties such as compression ratio, compressive elastic modulus and hardness may be significantly reduced. If the number of moles of the polyisocyanate compound is too large as compared with the number of moles of the chain extender, the hardness, viscosity or molecular weight of the polyurethane resin to be produced may become excessively large, and the support pad produced using such a polyurethane resin may have a proper compression ratio, It may be difficult to ensure physical properties such as compression modulus and hardness.

The polyisocyanate compound means a compound having a plurality of isocyanate groups. Such a polyisocyanate compound may be a polyisocyanate containing an aliphatic, alicyclic, araliphatic, aromatic and heterocyclic functional group, and may be represented by the formula Q (NCO) n. Wherein n is an integer from 2 to 4 and Q can be an aliphatic, alicyclic, aromatic or araliphatic hydrocarbon functional group containing 2 to 18, preferably 6 to 10, C atoms. Specific examples of the polyisocyanate compound include ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate (HDI), 1,12-dodecane diisocyanate, cyclobutane-1,3 Diisocyanate, cyclohexane-1,3-diisocyanate, cyclohexane-1,4-diisocyanate, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane, 2,4-hexahydrotoluene diisocyanate, 2,6-hexahydrotoluene diisocyanate, hexahydro-1,3-phenylene diisocyanate, hexahydro-1,4-phenylene diisocyanate, perhydro- Diphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 1,4-dorol diisocyanate (DDI) , 4,4'-stilbene diisocyanate, 3,3'- Methylene-4,4'-biphenylene diisocyanate (TODI), toluene 2,4-diisocyanate, toluene 2,6-diisocyanate (TDI), diphenylmethane-2,4'-diisocyanate (MDI) Diphenylmethane diisocyanate (MDI), diphenylmethane-4,4'-diisocyanate (MDI), naphthylene-1,5-isocyanate (NDI) or a mixture of two or more thereof.

The chain extender may include ethylene glycol and 1,4-butanediol, preferably ethylene glycol and 1,4-butanediol in a molar ratio of 1: 9 to 9: 1, more preferably 5: 9: 1. ≪ / RTI > When ethylene glycol and 1,4-butanediol are used as a chain extender, the polyurethane resin and the support pad using the polyurethane resin can have an appropriate density or hardness, And the compressibility, elastic modulus, density and hardness required in the final product can be secured.

On the other hand, the first polyurethane resin or the second polyurethane resin may have a weight average molecular weight of 100,000 g / mol to 1,000,000 g / mol, preferably 200,000 g / mol to 800,000 g / mol. In addition, the first polyurethane resin or the second polyurethane resin may have a viscosity of 100,000 cps to 1,000,000 cps. The weight average molecular weight and viscosity of such a polyurethane resin may be based on a solids level of 30%. In the process of producing the polyurethane support pad, dimethylformamide mixed with the polyurethane resin may dissolve in water to form pores while escaping. When a polyurethane resin having the molecular weight or viscosity within the above range is used, Can be formed with a uniform size and a uniform distribution.

The first or second polyester polyol may have an average hydroxyl value of 20 to 100 mg KOH / g or a weight average molecular weight of 500 g / mol to 5,000 g / mol. If the average hydroxyl value or the weight average molecular weight of the first or second polyester polyol is too low, the strength or hardness of the polyurethane resin to be synthesized may be significantly lowered, and the average hydroxyl value of the first or second polyester polyol If the weight average molecular weight is too large, the hardness of the polyurethane resin may be greatly increased, and the compressibility or compressive modulus of the support pad produced using the polyurethane resin may be greatly lowered.

The polyurethane resin composition can form a polyurethane support pad having pores formed therein through a wet solidification process, which is caused by phase separation of the first and second polyurethane resins, water and DMF. Specifically, the first and second polyurethane resins dissolved in an organic solvent containing at least one selected from the group consisting of dimethylformamide (DMF) and methyl ethyl ketone (MEK) are immersed in a coagulation tank filled with a constant aqueous solution The first and second polyurethane resins and DMF are phase-separated, and the phase-separated organic solvent is replaced with an aqueous solution or water to form pores. After the pores are formed, the polyurethane resin pads that can be used for manufacturing the support pad of the polishing apparatus can be manufactured by removing the residual organic solvent through the washing process and the drying process.

Wherein the polyurethane resin composition contains the first polyurethane resin and the second polyurethane resin in a weight sum of 1 to 80 wt%; 10 to 90 wt% of the DMF solvent; And 0.05 to 15 wt% of the surfactant.

The surfactant may be an anionic surfactant, a nonionic surfactant, or a mixture thereof.

The anionic surfactant can uniformly penetrate the water over the entire area of the composition to be coagulated and prevent the phase separation of the polyurethane resin, water, and organic solvent from concentrating on a certain portion, Can be formed very uniformly.

Examples of the anionic surfactant include dodecylbenzenesulfonic acid, dodecylbenzenesulfonic acid derivatives, succinic acid, succinic acid derivatives, dodecylsulfate, dodecylsulfate derivatives, and mixtures of at least one of the foregoing. The use of dodecylbenzenesulfonic acid or a derivative thereof as an anionic surfactant and succinic acid or its derivative is used to control the shape and size of the pores formed in the support pad to suitably control the physical properties of the support pad .

The nonionic surfactant can increase the adsorption force of the support pad or flatten the surface of the pad. Examples of such nonionic surfactants include silicone-based polymers, silicone oils, glycerol-based polymers, and hydrocarbon-based polymers. Such a nonionic surfactant can be used by suitably adjusting the content in consideration of the physical properties of the support pad to be produced and the process conditions.

The polyurethane resin composition may further include at least one additive selected from the group consisting of fillers, water repellents, pore size regulators and pigments.

On the other hand, according to another embodiment of the invention, there can be provided a polyurethane support pad comprising a wet coagulation of a polyurethane resin composition.

As described above, the polyurethane support pad made from the polyurethane resin composition comprising the first polyurethane resin and the second polyurethane resin is formed by uniformly forming long and large pores in the interior thereof, so that the low hardness, the excellent compression ratio and the high compression It may have a modulus of elasticity. In addition, since the polyurethane support pad has long and large pores uniformly formed therein, air generated between the support pad and the polishing target film can be easily transferred to the inside and uniformly dispersed in the entire area. Therefore, It is possible to minimize the defects that may occur.

The polyurethane support pad may have a thickness of 0.1 to 3 mm, preferably 0.5 to 2.0 mm, and may have a density of 0.10 to 0.50 g / cm 3, preferably 0.15 to 0.30 g / cm 3.

In addition, the polyurethane support pad may have Asker C hardness of 20 to 30, and Asker C hardness of 21 to 25, as prepared using the specific polyurethane resin composition described above.

The polyurethane support pad may have a compressibility of 30% to 55%, preferably 35% to 50%, and may have a compressive modulus of 90% or more, preferably 93% or more.

The pores distributed within the polyurethane support pad may have a flatness ratio (ratio of length to width) of 2 to 10, preferably a flatness ratio of 3 to 7.

In addition, the polyurethane support pad may include pores having a length of 50 mu m to 1500 mu m.

The length of the pores refers to a straight line distance between the highest point and the lowest point in one of the pores. The width of the pores is the shortest distance among the straight lines connecting two points on the pore boundary in a direction perpendicular to the straight line corresponding to the length of the pores. .

The long and large pores inside the polyurethane support pad can lower the hardness of the pad to produce a soft pad having a high compressibility and can easily trap the air trapped between the support pad and the film to be polished, It is possible to uniformly distribute the force applied in the polishing step to the entire support pad and the entire object to be polished, thereby minimizing defects that may occur during polishing.

Meanwhile, the polyurethane support pad may be formed by solidifying the polyurethane resin composition. Specifically, the polyurethane support pad comprises the steps of: forming the polyurethane resin composition; Coating or injecting the polyurethane resin composition into a predetermined substrate or frame to form a coating layer; Solidifying the coating layer; And a step of washing, dehydrating and drying the coagulated product of the composition.

In the step of solidifying the coating layer, a substrate or a frame on which the coating layer is formed is coagulated with an organic solvent containing at least one selected from the group consisting of dimethylformamide (DMF) and methyl ethyl ketone (MEK) Into a coagulation bath filled with a 1 to 20 wt% aqueous solution of DMF. In the solidification process, the organic solvent in the polyurethane resin is replaced with water, and the polyurethane resin gradually coagulates, thereby forming a plurality of pores. By adjusting the concentration of the organic solvent in the coagulation bath, the coagulation time and the pore size in the support pad can be controlled.

In the washing step of the solidified product, an organic solvent or an additive can be removed, and a method and an apparatus known to be usable in the method of manufacturing a supporting pad can be used without any limitation.

In the step of solidifying the coating layer, the substrate or the frame on which the coating layer is formed may be put into a coagulation tank filled with the organic solvent and water. In the solidification process, the organic solvent (dimethylformamide (DMF) or methyl ethyl ketone (MEK)) is replaced with water in the polyurethane resin so that the polyurethane resin gradually coagulates and thus a large number of pores can be formed . The concentration of the aqueous solution and the amount of the aqueous solution or the water filled in the coagulation bath are not particularly limited and can be appropriately adjusted according to the reaction conditions and physical properties of the support pad to be produced. After the solidification process, water and an organic solvent may remain in the polishing pad, and water, organic solvent, and other components may be removed from the polishing pad by washing the solidified product and drying it in an oven.

The manufacturing process of the polyurethane support pad may include polishing (or buffing) the surface of the wet coagulation product. The polishing step is a step of cutting a surface of a low hardness polyurethane film (100% moduli 1 to 10) using a roll wound with sandpaper rotated at high speed, and is a process of applying high energy.

In this polishing (or buffing) process, the polished film may be cut several hundreds of um at a time, or may be cut several times several tens of um. When a low hardness film is polished at a time, a difference in thickness or a difference in abrasion (buffing) level may occur in the machine direction (MD) direction, and the unevenly accumulated energy in the support pad may cause a polishing film, It may be unevenly transferred to the glass substrate of the display or the like to cause lines or streaks in the direction of the TD (Transverse Direction).

Further, in the manufacturing process of the polyurethane support pad, it may further include forming an adhesive layer on the surface of the buffered wet solidified product. This adhesive layer may be formed using any method and configuration known to be used to make the final product of the backing pad without any particular limitation. For example, the adhesive layer may be formed by applying a certain adhesive, for example, a pressure sensitive adhesive (PSA) or the like, to the surface of the wet coagulated material or the surface of the surface polished wet coagulated material, And laminating a pressure-sensitive double-side adhesive film on the surface of the surface-polished wet coagulation product.

According to the present invention, there is provided a polyurethane resin composition capable of uniformly forming long and large pores therein to provide a support pad having low hardness, excellent compression ratio and high compression modulus, and a polyurethane support pad made from such a resin composition .

Fig. 1 is a cross-sectional SEM photograph of the polyurethane support pad obtained in Example 1. Fig.
2 is a cross-sectional SEM photograph of the polyurethane support pad obtained in Example 2. Fig.
3 is a cross-sectional SEM photograph of the polyurethane support pad obtained in Example 3. Fig.
4 is a cross-sectional SEM photograph of the polyurethane support pad obtained in Comparative Example 1. Fig.
Fig. 5 is a cross-sectional SEM photograph of the polyurethane support pad obtained in Comparative Example 2. Fig.
6 is a cross-sectional SEM photograph of the polyurethane support pad obtained in Comparative Example 3. Fig.

The invention will be described in more detail in the following examples. However, the following examples are illustrative of the present invention, and the present invention is not limited by the following examples.

[ Synthetic example : Manufacture of polyurethane resin]

Synthesis Example 1  : Synthesis of Polyurethane Resin ( PU1 )

Adipic acid, diethylene glycol and ethylene glycol were reacted in a molar ratio of 1: 0.5: 0.5 at a temperature of 200 캜, a reduced pressure of 500 to 760 mmHg and a vacuum atmosphere to synthesize a polyester polyol.

The synthesized polyester polyol, chain extender (ethylene glycol), polyisocyanate and DMF were placed in a reactor and polymerization was carried out at a temperature of 80 ° C to obtain a polyurethane resin (containing about 25% by weight of the polyisocyanate group-derived component) Were synthesized.

Synthesis Example 2  : Synthesis of Polyurethane Resin ( PU2 )

A polyurethane resin was synthesized in the same manner as in Synthesis Example 1 except that the polyisocyanate group-derived component was about 20% by weight.

Synthesis Example 3  : Synthesis of Polyurethane Resin ( PU3 )

Polyurethane resin containing about 20% by weight of the polyisocyanate group-containing component was synthesized in the same manner as in Synthesis Example 1, except that adipic acid, ethylene glycol and 1,4-butanediol were used in a molar ratio of 1: 0.5: 0.5 Respectively.

Synthesis Example 4  : Synthesis of Polyurethane Resin ( PU4 )

A polyurethane resin containing about 25% by weight of the polyisocyanate group-containing component was synthesized in the same manner as in Synthesis Example 1, except that adipic acid, ethylene glycol and 1,4-butanediol were used in a molar ratio of 1: 0.5: 0.5 Respectively.

Synthesis Example 5  : Synthesis of Polyurethane Resin ( PU5 )

A polyurethane resin containing about 30% by weight of polyisocyanate group-containing components was synthesized in the same manner as in Synthesis Example 1, except that adipic acid, ethylene glycol and 1,4-butanediol were used in a molar ratio of 1: 0.5: 0.5 Respectively.

< Example  And Comparative Example : Preparation of polyurethane resin composition and preparation of polyurethane support pad &gt;

1. Preparation of polyurethane resin composition

Using the polyurethane resin obtained in the above Synthesis Example, a polyurethane resin composition was prepared with the composition shown in Table 1 below.

Specifically, the components shown in Table 1 below were mixed and stirred at a high speed for 10 minutes with a paint shaker, followed by centrifugation at 3000 rpm for 10 minutes to obtain a slurry polyurethane resin composition.

2. Preparation of polyurethane support pads

The resulting polyurethane resin composition was coated on a PET film to a thickness of 2.00 mm and then solidified in a coagulation bath filled with 2 to 15% aqueous DMF solution. Thereafter, the resulting coagulum was washed with water, dehydrated and dried to prepare a polyurethane support pad. SEM photographs of the prepared polyurethane support pads are shown in Figs. 1 to 6.

The polyurethane resin compositions of Examples and Comparative Examples Polyurethane resin
(g) Nonionic
Surfactants Anionic
Surfactants coloring agent DMF Water repellent agent Filler Example 1 PU2 (40) PU5 (60) One 4.3 5 55 2 2 Example 2 PU1 (30) PU3 (70) One 4.3 5 50 2 2 Example 3 PU1 (50) PU3 (50) One 4.3 5 50 2 2 Comparative Example 1 PU5
(100) One 4.3 5 60 2 2 Comparative Example 2 PU3
(100) One 4.3 5 60 2 2 Comparative Example 3 PU1
(100) One 4.3 5 60 2 2

< Experimental Example >

Experimental Example 1 : Density measurement of supporting pads

The polyurethane support pads obtained in the above Examples and Comparative Examples were prepared in the size of 25 mm * 30 mm, and the thicknesses were measured. Then, the weights of these specimens were measured to calculate the density. Then, the weight of the specimen was measured five times repeatedly, the density values of the respective specimens were obtained, and the density of the support pads was calculated from the average values thereof.

Experimental Example 2 : Of support pads Compression ratio  And Compression recovery rate  Measure

The compressibility and the compression recovery rate of the polyurethane support pad obtained in the above Examples and Comparative Examples were measured according to JIS L1021-16.

Specifically, the polyurethane support pads obtained in the above Examples and Comparative Examples were cut to prepare specimens having a size of 25 mm * 30 mm. The initial thickness was measured using a dial gauge (T0) after the initial load of 100 g / cm2 was applied to the specimen for 30 seconds. The specimen was subjected to a load of 1120 g / cm2 for 5 minutes and then the thickness was measured under pressure (T1). After removing all the loads and leaving for 5 minutes, the thickness was measured after applying an initial load of 100 g / cm 2 for 30 seconds (T0 '). The compression ratio and the compression recovery rate were calculated by applying the following equations to each of the measured thicknesses.

[formula]

Compression ratio (%) = (T0 - T1) * 100 / T0

Compression recovery rate (%) = (T0 '- T1) * 100 / (T0 - T1)

The results of Experimental Examples 1 to 2 are shown in Table 2 below.

Density (g / cm3) Compressibility (%) Compressive modulus (%) Example 1 0.19 54 97 Example 2 0.25 45 96 Example 3 0.22 51 97 Comparative Example 1 0.25 11 91 Comparative Example 2 0.35 15 90 Comparative Example 3 0.20 50 97

As shown in Table 1, it was confirmed that the examples exhibited a relatively low density and an excellent compression ratio of 45% and a high compression modulus of 95% or more.

1 to 3, the support pads of Examples 1 to 3 have a plurality of pores having a length of about 100 m to 1500 m and a flatness ratio (ratio of length to width) of 3 to 7 Were uniformly distributed.

On the contrary, it was confirmed that the hardness of the support pad of Comparative Example 1 was relatively high, and the compressibility and compressive modulus of elasticity were lower than those of the support pads of the Examples. That is, when the content of the residues of the polyisocyanate compound contained in each of the polyurethane resins of the support pad is more than 30% by weight, the formed pores become homogeneous and have a proper density, but the strength of the polyurethane resin The compressibility of the support pad was considerably lowered.

The density and hardness of the support pad of Comparative Example 2 were too small and the compressive modulus of elasticity was also lower than that of the examples. . That is, when the content of the residues of the polyisocyanate compound contained in each of the polyurethane resins of the support pad is less than 20% by weight, the inner wall of the pores may collapse during the production of the support pad or the thickness may not be secured easily, It was confirmed that the compressibility and compressive elastic modulus of the support pad were lower than those of the examples.

Therefore, when the first polyurethane resin and the second polyurethane resin are mixed and used as in the embodiment, the content of the residues of the polyisocyanate compound contained in each of the first polyurethane resin and the second polyurethane resin is 20 To 30% by weight, it is possible to produce a support pad having improved physical properties.

As shown in FIGS. 4 and 5, it was confirmed that the support pads of Comparative Example 1 had a relatively small pore size, a small size and a nonuniform distribution. In the support pad of Comparative Example 2, And it has a wide shape in the width direction, and thus it is confirmed that the quality of the support pad is lower than that of the support pad of the embodiment.

On the other hand, it was confirmed that the support pad of Comparative Example 3 can achieve a compressibility and a compressive modulus equivalent to those of the support pad of the embodiment, but as shown in FIG. 6, the pores formed therein are not only uneven, And it was confirmed that a large number of pores having a very large size were formed. When the support pad of Comparative Example 3 is used, it is difficult to sufficiently secure the cushion performance and the attraction force for the object to be polished, and the object to be polished can not be firmly fixed on the support pad in the polishing process, so that accurate polishing can not be achieved.

Therefore, according to the support pad of the embodiment, it is possible to improve the cushion property and the attracting force of the object to be polished, and it is possible to securely fix the object on the pad when polishing the object, thereby preventing the polishing quality from being lowered.

Claims (20)

A first polyurethane resin comprising a residue of a first polyester polyol, a residue of a polyisocyanate compound, and a residue of a chain extender, the second polyurethane resin comprising a reactant between a polycarboxylic acid having 2 to 10 carbon atoms and a polyol comprising diethylene glycol;
A residue of a second polyester polyol comprising a reactant between a polycarboxylic acid having 2 to 10 carbon atoms and at least one diol compound selected from the group consisting of ethylene glycol and 1,4-butanediol, a residue of a polyisocyanate compound and a chain extender A second polyurethane resin comprising a moiety;
An organic solvent containing at least one selected from the group consisting of dimethylformamide (DMF) and methyl ethyl ketone (MEK); And
A surfactant;
Wherein the content of the residues of the polyisocyanate compound contained in each of the first polyurethane resin and the second polyurethane resin is 20 to 30 wt%
A polyurethane resin composition for the production of a support pad for a polishing apparatus.
The method according to claim 1,
Wherein the content of the residues of the polyisocyanate compound contained in each of the first polyurethane resin and the second polyurethane resin is different.
The method according to claim 1,
Wherein the first polyurethane resin comprises 20 to 24 wt% of the residue of the polyisocyanate compound,
And the second polyurethane resin comprises 25 to 30% by weight of the residue of the polyisocyanate compound.
The method according to claim 1,
Wherein said first polyurethane resin comprises from 25 to 30% by weight of residues of said polyisocyanate compound,
And the second polyurethane resin comprises 20 to 24% by weight of the residue of the polyisocyanate compound.
The method according to claim 1,
Wherein the first polyurethane resin and the second polyurethane resin are contained in a weight ratio of 2: 8 to 6: 4.
The method according to claim 1,
Wherein the polyester polyol has an average hydroxyl value of from 20 to 100 mgKOH / g.
The method according to claim 1,
Wherein each of the first polyester polyol and the second polyester polyol has a weight average molecular weight of 500 to 5,000.
The method according to claim 1,
Wherein each of the first polyurethane resin and the second polyurethane resin has a weight average molecular weight of 100,000 g / mol to 1,000,000 g / mol.
The method according to claim 1,
Wherein the polycarboxylic acid having 2 to 10 carbon atoms comprises a dicarboxylic acid having 4 to 8 carbon atoms.
The method according to claim 1,
Wherein the chain extender comprises at least one diol compound selected from the group consisting of ethylene glycol and 1,4-butanediol.
The method according to claim 1,
The polyisocyanate compound may be at least one selected from the group consisting of diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate (HDI), 1,12-dodecane diisocyanate, cyclobutane-1,3-diisocyanate, 1,3-diisocyanate, cyclohexane-1,4-diisocyanate, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane, 2,4- Toluene diisocyanate, 2,6-hexahydrotoluene diisocyanate, hexahydro-1,3-phenylene diisocyanate, hexahydro-1,4-phenylene diisocyanate, perhydro-2,4'- 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 1,4-dorol diisocyanate (DDI), 4,4'-diphenylmethane diisocyanate, Stilbene diisocyanate, 3,3'-dimethyl-4,4'-biphenylene diisocyanate Toluene diisocyanate (TDI), diphenylmethane-2,4'-diisocyanate (MDI), 2,2'-diphenylmethane diisocyanate ( MDI), diphenylmethane-4,4'-diisocyanate (MDI), and naphthylene-1,5-isocyanate (NDI).
The method according to claim 1,
Wherein the polyol containing diethylene glycol further comprises at least one diol compound selected from the group consisting of ethylene glycol and 1,4-butanediol.
The method according to claim 1,
Wherein the polyol containing diethylene glycol comprises 10 mol% to 100 mol% of diethylene glycol.
The method according to claim 1,
1 to 80 wt% of the total weight of the first polyurethane resin and the second polyurethane resin;
10 to 90 wt% of the DMF solvent; And
And 0.05 to 15 wt% of the surfactant.
The method according to claim 1,
Wherein the polyurethane resin composition further comprises at least one additive selected from the group consisting of a filler, a water repellent agent, a pore size regulator, and a pigment.
A polyurethane support pad comprising a wet coagulate of the polyurethane resin composition of claim 1.
17. The method of claim 16,
A polyurethane backing pad having a density of 0.10 to 0.35 g / cm3.
17. The method of claim 16,
A polyurethane support pad according to JIS L1021-16 having a compression ratio of 30% or more and a compression recovery rate of 95% or more.
17. The method of claim 16,
And a pore having a planar ratio of 3 to 10 (ratio of length to width).
17. The method of claim 16,
And pores having a length of from 50 mu m to 1500 mu m.

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