KR20130076074A - Spherical polymer powder and preparation method thereof - Google Patents

Abstract

PURPOSE: A manufacturing method of polyurethane spheres is provided to improve the recovery rate and compression rate of a polyurethane sphere by a laminated structure which has a uniform sized spherical shape and uneven parts on the surface thereof. CONSTITUTION: A manufacturing method of polyurethane spheres comprises a step of emulsifying a solution including a polyol, an isocyanate compound, a chain extender, and a suspending agent; and a step of manufacturing the polyurethane spheres by polymerizing the emulsion. The second step includes a step of carrying out a polymerization while stirring and dropping the emulsion for 1-3 hours into a reactor by using a pump. The average particle diameter of the polyurethane spheres is 2-200 microns, the compression elasticity is 200 kgf/cm^2 or less, and the recovery rate is 15% or more.

Description

Spherical Polyurethane Powder and its Manufacturing Method {SPHERICAL POLYMER POWDER AND PREPARATION METHOD THEREOF}

The present invention relates to a spherical polyurethane powder having excellent adhesion and a method of manufacturing the same, and more particularly, has a specific gravity is lighter than the existing polyurethane beads, excellent adhesion in cosmetics and excellent durability, as well as recovery and compression ratio The present invention relates to a method for producing a spherical polyurethane powder that is equivalent to or more than that, and a spherical polyurethane powder produced therefrom.

Spherical polymer powder is spherical in shape and has excellent rheology, which is widely used in various industrial fields such as optical articles, signs, displays, lighting fixtures, cosmetics, paints, and plastic molded articles.

Polyurethane beads have a higher refractive index than PMMA, and have a soft focus (SOFT FOCUSS) effect when used in cosmetic formulations to improve wrinkles, and have a soft touch when used in mascara.

However, if the specific gravity in cosmetic formulations may be submerged during manufacture and if the surface is too smooth, it tends to play separately from the formulation. Therefore, it is well mixed with various formulations used in cosmetics, does not sink, and has good adhesion to skin, which is required to improve the natural effect.

However, the polyurethane powders developed to date have a high specific gravity, so that the sedimentation rate is high, and thus excellent adhesion cannot be obtained.

In order to solve the problems of the prior art as described above, an object of the present invention is to proceed with a polymerization reaction using a polyol, an isocyanate compound, and a chain extender, which have been used in the production of conventional polyurethane powder, by adjusting the conditions of the polymerization reaction. The present invention aims to provide a method for producing spherical polyurethane powder having a low specific gravity, excellent adhesion, excellent sustainability, and excellent recovery and compression ratios.

In addition, another object of the present invention is to provide a spherical polyurethane powder suitable for use in cosmetics because it has excellent physical properties such as solvent resistance, chemical resistance, extrusion elasticity and recovery rate, low specific gravity and excellent adhesion due to the surface properties. .

(A) emulsifying a solution comprising a polyol, an isocyanate compound, a chain extender and a suspension stabilizer, and

(b) preparing a polyurethane powder by polymerizing the emulsion obtained in step (a);

The step of preparing the polyurethane powder, including the step of proceeding the polymerization while dropping the emulsion in the reactor for 1 hour to 3 hours using a metering pump while maintaining the stirring of the emulsion obtained in step (a),

Provided is a method for producing a spherical polyurethane powder having a low specific gravity having irregularities on the surface and an excellent adhesion, having an average particle diameter of 2 to 200 µm, a compression modulus of 200 kgf / cm 2 or less, and a recovery rate of 15% or more.

The stirring is preferably maintained at 400RPM to 600RPM. In addition, the polymerization reaction is performed for 6 to 40 hours at a temperature of 40 to 90 ℃, the stirring speed is preferably maintained at 100 to 300 rpm. In addition, the step of emulsifying may include performing stirring for 5 to 60 minutes at a temperature of 10 to 30 ℃.

In addition, the present invention has a spherical spherical spherical powder having an average particle diameter of 2 to 200 µm, a compressive modulus of 200 kgf / cm 2 or less, a recovery rate of 15% or more, and an uneven surface having irregularities, and excellent adhesion. It provides a polyurethane powder of.

Hereinafter, the present invention will be described in detail.

The present invention relates to a method of polymerizing by slowly dropping the emulsion into the reactor, unlike the polymerization of the polyurethane powder (which is also referred to as polyurethane beads) directly into the reactor and polymerized.

When the polymerization proceeds in this way, since the lamination is performed during the polymerization process, the specific gravity is lower than that in the case of forming the network structure at once, thereby improving the adhesiveness, and due to the soft properties of the polyurethane itself, mechanical properties such as compression rate and recovery rate are It can show more than equivalent effect.

In particular, according to the present invention, due to the laminated structure mainly formed with irregularities on the surface while forming a uniform size sphere, the specific gravity is lighter than the existing three-dimensional structure, it is possible to provide a polyurethane powder with a recovery rate and compression ratio equal or more.

Due to this reduction in specific gravity and irregularities of the surface, the present invention can make a polyurethane powder excellent in adhesion and does not sink in cosmetic formulations.

According to one embodiment of the present invention, (a) emulsifying a solution containing a polyol, an isocyanate compound, a chain extender and a suspension stabilizer, and (b) polymerizing the emulsion obtained in step (a) to It includes a step of preparing a urethane powder, the step of preparing a polyurethane powder, dropping the emulsion solution to the reactor for 1 hour to 3 hours using a metering pump while maintaining the stirring of the emulsion obtained in the step (a) ( It has a spherical shape of the spherical surface having unevenness on the surface having an average particle diameter of 2 to 200 µm, a compressive modulus of 200 kgf / cm 2 or less, and a recovery rate of 15% or more, including a step of proceeding polymerization while dropping). A method for producing a polyurethane powder is provided.

According to the present invention, the polyurethane powder may have a three-dimensional network structure in molecular structure. In this case, the present invention does not proceed with polymerization by dispersing a suspension (ie, emulsion) at a time during the polymerization, but by adding the suspension to the polymerization reactor step by step to perform polymerization, thereby allowing the inner wall to be stacked on the existing polyurethane powder. It can give a layer to and form an uneven structure whose surface is not smooth.

The polyurethane powder thus formed has an average particle diameter of 2 to 200 μm, a compressive modulus of 200 kgf / cm 2 or less, and a recovery ratio of 15% or more. The specific gravity is 80% of that of the polymerized product at the same time while maintaining existing properties. Can be. According to the present invention, due to the low specific gravity, it is possible to slow down the sedimentation rate to the existing 80% level to improve the adhesion.

That is, in the past, an emulsion was prepared by a homogenization suspension polymerization method using a chain extender together with a polyol and an isocyanate compound monomer, and a polyurethane powder was prepared at once by putting it in an aqueous system. However, the polyurethane powder according to the above method was excellent in compressive modulus and recovery rate, but when it is mixed with cosmetic formulations, the adhesion of the surface is insufficient and sinks over time, and it is difficult to use in cosmetics.

However, in the present invention, by forming a three-dimensional network structure by using the sequential surface lamination of the polyurethane powder through the stepwise polymerization, the specific gravity is lower than that polymerized by the conventional general method, it does not easily go to the cosmetic manufacturing. In addition, the polyurethane powder according to the present invention includes an uneven structure on the surface, it was confirmed that the adhesion is improved due to the uneven surface. That is, after the core is produced to some extent by the dropping of the emulsion added at a constant speed during powder production, the stack is continuously laminated to the surface of the core by dropping the emulsion added stepwise for a specific time, and the laminated structure It has an uneven structure. Thus produced powder has a specific gravity is lightened by the structure that is continuously thinly laminated, thereby improving the adhesion. At this time, the suspension polymerization is carried out by adjusting the dropping rate of the emulsion into the polymerization reactor, and also when the emulsion is added to the polymerization reactor in a state in which stirring is maintained, not in a stationary state, an excellent effect can be obtained.

Therefore, the step of preparing the polyurethane powder includes a configuration for dropping the emulsion step by step. Preferably, the step of preparing the polyurethane powder is not put at the same time to polymerize the emulsion obtained in step (a), but gradually the polyurethane powder using a metering pump over 1 hour to 3 hours of 6 hours polymerization reaction time Laminating.

In addition, the step of emulsifying includes mixing a polyol, an isocyanate compound and a chain extender, and adding it to a solution containing a suspension stabilizer to prepare an emulsion. In this case, a homogenized emulsion may be obtained using a homogenizer. The emulsification conditions are not particularly limited, but may be a conventional method, but may be preferably performed for 5 to 60 minutes at a temperature of 10 to 30 ℃. In addition, when preparing the emulsion, ionized water may be used as the dispersion medium, the amount is not particularly limited.

In other words, the present invention obtains droplets of the desired particle size distribution through the emulsification process, and then put the emulsion into the reactor 1 in a four-necked reactor using a metering pump while continuously maintaining high speed agitation at 400 RPM to 600 RPM. Dropping for ˜3 hours.

The polymerization is carried out within 6 to 40 hours at a temperature of 40 to 90 ℃ considering the amount of the residual monomer in a nitrogen atmosphere. At this time, the polymer powder produced during the polymerization reaction does not sink, so that the stirring speed should be maintained appropriately, and also the reactor containing the emulsion must be stirred to prevent the emulsion from being released. Preferably, the stirring speed during the polymerization reaction is preferably maintained at 100 to 300 rpm.

In addition, the reactor containing the emulsion should be able to maintain a high-speed stirring state between 400 ~ 600 RPM, preferably 500 RPM. At this time, if the stirring speed is less than 400 RPM, the emulsion state is released, there is a problem that large particles are generated or aggregated during polymerization, and if it exceeds 600 RPM, the particles become smaller and there is a problem in recovery.

In this case, the reactor containing the emulsion in the present invention is referred to as the first reactor, the reactor in which the emulsion is dropped and the polymerization occurs is referred to as a second reactor.

In the present invention, the homogenization suspension polymerization method generally used can be used, and the method is not particularly limited.

Through the polymerization reaction, when the polymer is produced, the reaction may be filtered to recover the polymer powder. Preferably, the present invention is filtered by filtering the polymer synthesized in the above process, washed with water and ethanol aqueous solution, and the filtrate is recovered by drying in a conventional manner, it is possible to finally obtain a spherical polymer powder.

Meanwhile, the polyol used in the present invention is ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, octanediol, neopentyl glycol, polypropylene glycol, polyethylene glycol, poly The thing which can react with an isocyanate group like single (epsilon) -caprolactone diol and polyhexamethylene carbonate diol, or a mixture and a copolymer can be used. The content of the polyol is preferably used in 30 to 80 parts by weight based on a total of 100 parts by weight of the total monomers. In the present invention, all monomers include polyols, isocyanate compounds and chain extenders.

The isocyanate compounds include triylene diisocyanate, 4,4'-diphenyl methane diisocyanate, xylene diisocyanate, metha xylene diisocyanate, 1,6-hexamenylene diisocyanate, isophorone diisocyanate and trifunctional or higher polyisocyanates. One or more selected from the group consisting of can be used. The content of the isocyanate compound may be used in the remaining amount according to the content of the chain extender described later based on 100 parts by weight of the total monomers.

That is, the content of the polyol and isocyanate compound can be appropriately adjusted to represent 100 parts by weight of the total monomer, can be calculated in a single ratio, the range is not particularly limited. Therefore, the content of the polyol and isocyanate may be appropriately adjusted so that the total monomer content is 100 parts by weight according to the content of the polyfunctional monomer described below.

In addition, it is preferable to use at least 1 type selected from the group consisting of a diol compound having 2 to 10 carbon atoms having a diol group. More preferably, the chain extender may use one or more selected from the group consisting of ethylene glycol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. At this time, the content of the chain extending agent is preferably used in 10 to 30 parts by weight based on 100 parts by weight of the total of the above-described total monomers. At this time, if the content is less than 10 parts by weight, the recovery rate is lowered to 15% or more due to low crosslinking density, and if the content of the chain extender exceeds 30 parts by weight, it gives a too hard feeling.

The suspension stabilizer is selected from the group consisting of polyvinyl pyrrolidone, polyvinyl methyl ether, polyethyleneimine, polymethyl methacrylate acrylic acid copolymer, polyvinyl alcohol, vinyl acetate copolymer, ethyl cellulose and hydroxypropyl cellulose. One or more compounds can be used. It is preferable to use the suspension stabilizer in 1-10 weight part with respect to 100 weight part of total monomers. At this time, if the content is less than 1 part by weight, there is a problem that a large amount of polymerized aggregates are generated in the emulsion stability, and if it exceeds 10 parts by weight, it is difficult to remove the suspension stabilizer in the polymer powder cleaning process.

On the other hand, according to another embodiment of the present invention, there is provided a polyurethane powder which is a spherical polymer powder produced by the above method.

The spherical polyurethane powder prepared by the present invention includes a concave-convex structure on the surface, and a coefficient of variation (Coefficient of Variation, C.V. value) is 40% or less and a product yield may be 90% or more. At this time, the irregularities on the surface of the spherical polyurethane powder is irregularly generated, and the irregularities may be generated on the surface of the powder to a height of about 0.2 to 0.5 μm compared to the spherical particles having a general smooth surface. In addition, the polymer powder has an average particle diameter of 2 to 200 µm, preferably 5 to 100 µm. In addition, the polymer powder is at least 20% to 40% lighter, and the surface roughness is excellent due to the roughness of the beads when the density of the beads made without using a metering pump as a result of specific gravity measurement is about 1.0 to 1.3. Do. More preferably, the polymer powder has a density of 0.8 to 1 and excellent adhesion sensory test results. In the present invention, the adhesion sensory test can be obtained by adding 0.5% of the beads to the cosmetic foundation formulation and measuring the degree of bleeding after applying it on the back of the hand.

In addition, the spherical polyurethane powder of the present invention is manufactured in a laminated structure, as shown in Figure 1 includes an uneven structure on the surface can improve the adhesion.

On the other hand, according to Stokes Law, the settling velocity increases as the density of the deposit is larger, the density of the fluid is smaller, the viscosity of the fluid is smaller, and the diameter of the deposit particles is larger. When all the conditions are equal, the sedimentation rate becomes smaller if the deposit density becomes smaller.

However, according to the present invention, since the polyurethane powder is spherical, the coefficient of variation, product yield and average particle size, recovery rate, and compressive elastic modulus are equal to or higher than the conventional one, and the specific gravity is light, so that the sedimentation rate is based on the STOKE law. You can see that it is much slower. Therefore, in the present invention, the sedimentation rate represented by the following Equation 1 is 0.00970 or less, and the sedimentation rate is lowered to the existing 80% level.

[Equation 1]

Where Vs is the rate of descent (sedimentation rate), μ is the viscosity of the fluid, ρs is the density of the sediment particles, ρ is the density of the fluid, D is the diameter of the sediment particles, and g is the gravitational acceleration.

According to the manufacturing method of the spherical polyurethane powder with excellent adhesion of the present invention, by polymerizing the emulsion after the emulsification process using a specific dropping method of the emulsion during polymerization, the concavo-convex structure is stacked on the surface in a lamination form than the conventional one This light weight makes it possible to produce a polymer powder having excellent adhesion by not sinking and making the surface smooth even when making a cosmetic formulation.

In addition, the polyurethane powder prepared according to the present invention is spherical and excellent in physical properties such as optical properties, powder flowability, processability and strength, and is very suitable for use in cosmetics as well as optical.

Figure 1 shows an electron micrograph of the polyurethane powder of Example 1 of the present invention.
Figure 2 shows an electron micrograph of the polyurethane powder of Comparative Example 1.

Hereinafter, preferred examples are provided to help understanding of the present invention, but the following examples are merely to illustrate the present invention, and the scope of the present invention is not limited by the following examples.

Example 1

30 parts by weight of caprolactone diol having a number average molecular weight of 2000 and two hydroxyl groups as a polyol and 50 parts by weight of a yellowing type isophorone diisocyanate having two isocyanate groups were added to the flask, followed by 1,4 as a chain extender. 20 parts by weight of butanediol were added. Then, 5 parts by weight of polyvinyl alcohol (PVA), a suspension stabilizer, was dissolved using ion water as a dispersion medium, and the mixture was administered to the solution, and homogenized for 20 minutes at a temperature of 8000 rpm and 20 ° C. using a high speed stirrer. Emulsification to prepare an emulsion. Subsequently, the emulsion was added to the first reactor and continuously dropped at 500 RPM for 3 hours using a metering pump for 3 hours while continuously stirring at 500 RPM for 6 hours at 50 ° C. under a nitrogen atmosphere. After the reaction, the temperature was raised to 75 ° C. for 4 hours. At this time, the stirring rate was maintained at 200 rpm during the polymerization reaction.

The polymer synthesized by the polymerization reaction was filtered, washed with water and an aqueous ethanol solution, and the filtrate was put in a vacuum oven and dried for one day to prepare a white odorless spherical polyurethane powder.

Example 2

In the same manner as in Example 1, the dropping time of the emulsion was shortened to 1 hour to prepare a white odorless spherical polyurethane powder.

Comparative Example 1

The dropping time of the emulsion was extended to 6 hours to prepare a white odorless spherical polyurethane powder.

Comparative Example 2

The polymerization reaction was carried out in the same manner as in Example 1, except that the emulsion was added to the four-neck reactor, which is the second reactor, at once. Thereafter, the polymer synthesized by the polymerization reaction was filtered, washed with water and ethanol aqueous solution, and the filtrate was put in a vacuum oven and dried for one day to prepare a white odorless spherical polyurethane powder.

Comparative Example 3

The same method as in Example 1 except that the emulsion was added to the first reactor and the polymerization reaction was carried out by dropwise addition to a four-necked reactor, which is the second reactor, for 3 hours using a metering pump in a stationary state without high-speed stirring. White odorless spherical polyurethane powder was prepared.

Comparative Example 4

The same method as in Comparative Example 3 except that the emulsion was added to the first reactor and the polymerization reaction was carried out by dropwise addition to a four-neck reactor, which is the second reactor, for 1 hour using a metering pump in a stationary state without high-speed stirring. White odorless spherical polyurethane powder was prepared.

Comparative Example 5

In the same manner as in Comparative Example 3 except that the polymerization reaction was carried out while the emulsion was added to the first reactor for 6 hours by using a metering pump in a fixed state without high-speed stirring when the emulsion was placed in the first reactor. The spherical polyurethane powder was produced by carrying out.

Experimental Example 1

[comparison analysis]

In order to compare the spherical polyurethane powders prepared in Example 1-2 and Comparative Example 1-5, SEM measurement, product yield measurement, average particle size, compressive modulus, recovery rate, sedimentation for each sample by the following method Velocity and adhesion test coefficient of variation were measured. Comparative analysis results are shown in Table 1. In addition, electron micrographs (SEM) photographs of the polyurethane powders of Example 1 and Comparative Example 1 are shown in FIGS. 1 and 2.

SEM measurement: Hitachi S-4300

-Product yield measurement: yield measurement after filtering

Average particle size: measured using Coulter Multisizer M3

-Compression modulus & recovery: MCTM 500

-Sedimentation rate: Measured by the following equation (1)

-Coefficient of variation (C.V.): measured by the following equation

-Adhesiveness: 0.5% of each polyurethane powder mixed with foundation cosmetic formulation is tested directly on the skin. Measure on the back of the hand after applying. When adhesion is excellent, it does not bury well and is marked 1 ~ 5 according to the degree of inquiries.

5: rarely buried

4: the amount that comes in close contact is less than the amount used

3: burying amount is about half of the amount used

2: A small amount of adhesion, but the amount of buried is more than the amount used

1: almost not buried mostly buried

[Equation 1]

In the above formula, each definition is as described above.

[Equation 2]

C.V. (%) = (Standard deviation of particle size / average particle size of particle) × 100

 SEM Average particle size C.V. Compressive modulus (kgf / cm3) % Recovery Adhesion Example 1 Good 9.2 38% 95 15 5 Example 2 Good 9.0 35% 92 18 4 Comparative Example 1 Good 8.4 36% 90 17 3 Comparative Example 2 Good 8.2 33% 91 20 2 Comparative Example 3 Coarse particle generation 9.0 30% 98 19 3 Comparative Example 4 Coarse particle generation 8.6 36% 90 18 3 Comparative Example 5 Coarse particle generation 8.5 37% 92 17 2

yield importance Sedimentation rate Example 1 94% 0.8652 0.00436 Example 2 92% 0.9025 0.00962 Comparative Example 1 93.50% 0.9224 0.00973 Comparative Example 2 90% 1.1856 0.01073 Comparative Example 3 92% 0.8954 0.00539 Comparative Example 4 89% 0.9625 0.00507 Comparative Example 5 885 1.0221 0.01034

As shown in Table 1, Table 2, and Figures 1-2, the spherical polyurethane powders prepared in Examples 1 to 2 of the present invention are all excellent in overall physical properties compared to Comparative Examples 1 to 5, in particular, adhesion It can be seen that this is excellent and the sedimentation rate is slow. In particular, Example 1-2 of the present invention, the specific gravity was reduced up to 20% compared to the polyurethane powder prepared without dropping the emulsion of Comparative Example 2 and also excellent adhesion test. In addition, the polyurethane powder according to the present invention was normally polymerized without abnormal polymerization during the polymerization process, so that the product yield was not significantly different from that of Comparative Example 2, and the average particle size was equal to or more than that.

Therefore, in the case of beads prepared by emulsion dropping under certain conditions of the present invention, the sedimentation rate was also slowed down due to the decrease in specific gravity and thus can be positioned without sinking in the cosmetic formulation.

On the other hand, Comparative Example 1 showed similar physical properties to the present invention, but the emulsion was added dropwise for too long, the specific gravity reduction effect was not large, the adhesion was also normal. That is, when the emulsion is dropped for a long time, the end of the reaction proceeds earlier than the uneven structure is laminated on the surface of the spherical polyurethane powder, so that the effect of reducing the specific gravity is not large.

Dropping too fast also reduces the specific gravity because it is faster to form a three-dimensional structure than the stacking speed, but is heavier than Example 1, which has been dropped for three hours. Therefore, it is necessary to proceed with the polymerization reaction by dropping the emulsion in the range of the present application.

In addition, Comparative Example 2 can be seen that the polymerization proceeds directly to the emulsion without stirring or dropping, so that the specific gravity is heavy and thus the sedimentation rate is large and the adhesion decreases.

In addition, in the case of Comparative Example 3-5, which was slowly added dropwise in the stopped state without continuously stirring the emulsion, it could be seen that coarse particles may be generated because the emulsion was released over time.

Thus, it can be seen that the spherical polymer powder of Examples 1-2 of the present invention exhibited an average level of particle size, coefficient of variation, and product yield equal to or more than Comparative Examples 1 to 5, and also showed excellent adhesion test without coarse particles. Therefore, the poly and powder of the present invention can be usefully used as an additive that can be used in cosmetic production.

Claims (11)

(a) emulsifying a solution comprising a polyol, an isocyanate compound, a chain extender and a suspension stabilizer, and
(b) preparing a polyurethane powder by polymerizing the emulsion obtained in step (a);
The step of preparing the polyurethane powder, including the step of proceeding the polymerization while dropping the emulsion in the reactor for 1 hour to 3 hours using a metering pump while maintaining the stirring of the emulsion obtained in step (a),
A method for producing spherical polyurethane powder having a low specific gravity having a concave-convex surface on the surface, having an average particle diameter of 2 to 200 μm, a compressive modulus of 200 kgf / cm 2 or less, and a recovery rate of 15% or more. The method of claim 1, wherein the agitation is a light-weight specific gravity to maintain 400RPM to 600RPM and excellent adhesion of the spherical polyurethane powder. According to claim 1, wherein the polymerization is carried out at a temperature of 40 to 90 ℃ for 6 to 40 hours, the stirring speed is maintained at 100 to 300 rpm, the specific gravity of the spherical polyurethane powder manufacturing method of excellent adhesion with excellent adhesion. . The method of claim 1, wherein the emulsifying step comprises the step of performing agitation for 5 to 60 minutes at a temperature of 10 to 30 ℃ light specific gravity and excellent adhesion of the spherical polyurethane powder production method. The method of claim 1, wherein the polyol is ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, octanediol, neopentylglycol, polypropylene glycol, polyethylene glycol, poly A method for producing a spherical polyurethane powder having a light specific gravity and excellent adhesion, using at least one selected from the group consisting of -ε-caprolactone diol, polyhexamethylene carbonate diol, and copolymers thereof. The method of claim 1, wherein the isocyanate compound is triylene diisocyanate, 4,4'-diphenyl methane diisocyanate, xylene diisocyanate, methaxylene diisocyanate, 1,6-hexamenylene diisocyanate, isophorone diisocyanate And a method for producing a spherical polyurethane powder having light specific gravity and excellent adhesion using at least one member selected from the group consisting of trifunctional or higher functional polyisocyanates. The method of producing a spherical polyurethane powder according to claim 1, wherein the chain extender has a specific gravity which is at least one selected from the group consisting of diol compounds having 2 to 10 carbon atoms having a diol group and excellent adhesion. The method of claim 1, wherein the suspension stabilizer is polyvinyl pyrrolidone, polyvinyl methyl ether, polyethyleneimine, polymethyl methacrylate acrylic acid copolymer, polyvinyl alcohol, vinyl acetate copolymer, ethyl cellulose and hydroxypropyl cellulose A method for producing a spherical polyurethane powder having a specific gravity of light and excellent adhesion, by using one or more selected from the group consisting of. The specific gravity manufactured by the method of any one of Claims 1-8 is 2-200 micrometers, the compressive modulus is 200 kgf / cm <2> or less, the recovery rate is 15% or more, and the specific gravity which has unevenness | corrugation on the surface is Light spherical polyurethane powder with excellent adhesion. 10. The spherical polyurethane powder according to claim 9, wherein the coefficient of variation (C.V value) is 40% or less and the density is 0.8 to 1. The spherical polyurethane powder according to claim 9, wherein the specific gravity having a sedimentation rate of 0.00970 or less is light and excellent in adhesion.
[Equation 1]

Where Vs is the sedimentation rate, μ is the viscosity of the fluid, ρs is the density of the sediment particles, ρ is the density of the fluid, D is the diameter of the sediment particles, and g is the gravitational acceleration.

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