Composition

Abstract

According to the present invention, it is possible to provide a composition comprising a resin component and a filler component comprising a filler having a specific gravity of 3 or more and a filler having a specific gravity of less than 3, which achieves a low specific gravity effect in a state where a filler is filled in a high content and in a state where realization of physical properties is sufficiently secured, and has improved storage stability without deterioration of physical properties such as a thermal conductivity, and a product comprising a heating element and the composition or a cured product thereof in thermal contact with the heating element.

Claims

1. A composition comprising: a resin component; and a filler component, wherein the filler component comprises a filler having a specific gravity of 3 or more and a filler having a specific gravity of less than 3, and a content of the filler component in the composition is 80 wt % or more, and the composition forms a cured product having a specific gravity of less than 3.

2. The composition according to claim 1, wherein the resin component is a polyol, an isocyanate compound, a urethane resin, an acrylic resin, an epoxy resin, an olefin resin or a silicone resin.

3. The composition according to claim 1, wherein the resin component comprises a difunctional isocyanate compound and a polyfunctional isocyanate compound having 3 to 10 isocyanate groups.

4. The composition according to claim 3, wherein the difunctional isocyanate compound has a functional group value according to equation 1 in a range of 0.5 to 1:
Functional group value=100N/M[Equation 1] wherein, N is a number of isocyanate groups included in the difunctional isocyanate compound, and M is a molar mass (unit: g/mol) of the difunctional isocyanate compound.

5. The composition according to claim 3, wherein the difunctional isocyanate compound has a molar mass in a range of 100 to 500 g/mol.

6. The composition according to claim 3, wherein the difunctional isocyanate compound is an aliphatic cyclic isocyanate compound.

7. The composition according to claim 3, wherein the polyfunctional isocyanate compound has a functional group value according to equation 1 in a range of 0.01 to 0.7:
Functional group value=100N/M[Equation 1] wherein, N is a number of isocyanate groups included in the polyfunctional isocyanate compound, and M is a molar mass (unit: g/mol) of the polyfunctional isocyanate compound.

8. The composition according to claim 3, wherein the polyfunctional isocyanate compound has a molar mass in a range of 300 to 1500 g/mol.

9. The composition according to claim 3, wherein the polyfunctional isocyanate compound is a compound represented by the following formula 3: ##STR00004## wherein, L.sub.7, L.sub.8 and L.sub.9 are each independently an alkylene group, an alkenylene group or an alkynylene group.

10. The composition according to claim 1, wherein the filler component comprises 60 wt % or more of the filler having a specific gravity of 3 or more.

11. The composition according to claim 1, wherein the filler component comprises the filler having a specific gravity of less than 3 in an amount of 10 to 65 parts by weight relative to 100 parts by weight of the filler having a specific gravity of 3 or more.

12. (canceled)

13. The composition according to claim 1, wherein the filler component comprises a first filler having a specific gravity of 3 or more and a D50 particle size in a range of 50 to 200 m and a second filler having a specific gravity of 3 or more and a D50 particle size in a range of 0.5 to 5 m.

14. The composition according to claim 13, wherein a content of the first filler in the filler component is in a range of 25 to 50 wt %.

15. The composition according to claim 13, wherein a content of the second filler in the filler component is in a range of 10 to 50 wt %.

16. The composition according to claim 13, wherein the second filler has a rectangular shape.

17. The composition according to claim 13, wherein the filler component further comprises a third filler having a specific gravity of 3 or more and a D50 particle size in a range of 10 to 30 m.

18. The composition according to claim 17, wherein a weight ratio (C3/C2) of the third filler (C3) to the second filler (C2) is 1 or less.

19. The composition according to claim 1, wherein the filler having a specific gravity of less than 3 has a D50 particle size in a range of 50 to 90 m.

20. The composition according to claim 1, wherein the cured product has a thermal conductivity of 3 W/m.Math.K or more.

21. A product comprising a heating element; and the composition of claim 1 or a cured product thereof in thermal contact with the heating element.

Description

MODE FOR INVENTION

[0095] Hereinafter, the present application will be described in detail through Examples, but the scope of the present application is not limited by Examples below.

Example 1

[0096] Spherical alumina (C1a) with a D50 particle size of 70 m, spherical alumina (C3a) with a D50 particle size of 20 m, rectangular alumina (C2) with a D50 particle size of 2 m, and rectangular aluminum hydroxide (AH) with a D50 particle size of 60 m were mixed in a weight ratio of 40:20:20:20 (C1a:C3a:C2:AH), respectively, to prepare a filler component. The specific gravity of alumina used is 3.965, and the specific gravity of aluminum hydroxide is 2.423.

[0097] The D50 particle size of the filler as mentioned herein is a particle diameter (median diameter) accumulated at 50% in a cumulative curve on the basis of a volume of a particle size distribution. Such a particle size can be defined as a particle diameter at a point where the particle size distribution is obtained on the basis of the volume and the accumulated value becomes 50% in the cumulative curve with 100% of the total volume. The D50 particle size could be measured using Marven's MASTERSIZER 3000 equipment in accordance with ISO-13320, where ethanol was used as the solvent.

[0098] The prepared filler component was mixed with a polyol and other additives (curing retardant, dispersant, flame retardant) in a weight ratio of 90:8:2 (filler component:polyol:additives), and the mixture was mixed and dispersed at 600 rpm in revolution and 500 rpm in rotation for 3 minutes or so with a paste mixer and then the generated heat was confirmed, and defoamed in a vacuum state at 600 rpm in revolution and 200 rpm in rotation for 4 minutes, thereby preparing a main composition.

[0099] The polyol was a caprolactone polyol, in which one obtained by reacting 1,4-butanediol and caprolactone in a weight ratio of 1:2.79 (1,4-butanediol:caprolactone) was used.

[0100] In addition, the prepared filler component was mixed with an isocyanate mixture and other additives (hygroscopic agent, dispersant, flame retardant) in a weight ratio of 90:8:2 (filler component:isocyanate mixture:additives), and the mixture was mixed and dispersed at 600 rpm in revolution and 500 rpm in rotation for 3 minutes or so with a paste mixer and then the generated heat was confirmed, and defoamed in a vacuum state at 600 rpm in revolution and 200 rpm in rotation for 4 minutes, thereby preparing a curing agent composition.

[0101] As the isocyanate mixture, one obtained by mixing hexamethylene diisocyanate trimer (number of isocyanate groups: 3, molar mass: about 504.6 g/mol) and isophorone diisocyanate (number of isocyanate groups: 2, molar mass: about 222.3 g/mol) was used. The functional group value of hexamethylene diisocyanate trimer calculated by the following equation 1 is 0.59, and the functional group value of isophorone diisocyanate is 0.89.

Functional group value=100N/M[Equation 1]

[0102] In Equation 1, N is the number of isocyanate groups included in the isocyanate compound, and M is the molar mass (unit: g/mol) of the isocyanate compound.

[0103] The main composition and the curing agent composition as prepared were mixed in a volume ratio of 1:1 to prepare a composition.

Example 2

[0104] A composition was prepared as in the same method as in Example 1 above, except that spherical alumina (C1a) with a D50 particle size of 70 m, spherical alumina (C3a) with a D50 particle size of 20 m, rectangular alumina (C2) with a D50 particle size of 2 m, and rectangular aluminum hydroxide (AH) with a D50 particle size of 60 m were mixed in a weight ratio of 35:20:20:25 (C1a:C3a:C2:AH), respectively, to prepare a filler.

Example 3

[0105] A composition was prepared as in the same method as in Example 1 above, except that spherical alumina (C1a) with a D50 particle size of 70 m, rectangular alumina (C2) with a D50 particle size of 2 m, and rectangular aluminum hydroxide (AH) with a D50 particle size of 60 m were mixed in a weight ratio of 30:40:30 (C1a:C2:AH), respectively, to prepare a filler.

Example 4

[0106] A composition was prepared as in the same method as in Example 1 above, except that spherical alumina (C1a) with a D50 particle size of 70 m, rectangular alumina (C2) with a D50 particle size of 2 m, and rectangular aluminum hydroxide (AH) with a D50 particle size of 60 m were mixed in a weight ratio of 35:30:35 (C1a:C2:AH), respectively, to prepare a filler.

Example 5

[0107] A composition was prepared as in the same method as in Example 1 above, except that spherical alumina (C1a) with a D50 particle size of 70 m, rectangular alumina (C3b) with a D50 particle size of 20 m, rectangular alumina (C2) with a D50 particle size of 2 m, and rectangular aluminum hydroxide (AH) with a D50 particle size of 60 m were mixed in a weight ratio of 40:20:20:20 (C1a:C3b:C2:AH), respectively, to prepare a filler.

Example 6

[0108] A composition was prepared as in the same method as in Example 1 above, except that spherical alumina (C1a) with a D50 particle size of 70 m, rectangular alumina (C1b) with a D50 particle size of 70 m, rectangular alumina (C3b) with a D50 particle size of 20 m, rectangular alumina (C2) with a D50 particle size of 2 m, and rectangular aluminum hydroxide (AH) with a D50 particle size of 60 m were mixed in a weight ratio of 20:20:20:20:20 (C1a:C1b:C3b:C2:AH), respectively, to prepare a filler.

Example 7

[0109] A composition was prepared as in the same method as in Example 1 above, except that spherical alumina (C1a) with a D50 particle size of 70 m, spherical alumina (C3a) with a D50 particle size of 20 m, rectangular alumina (C2) with a D50 particle size of 2 m, and rectangular aluminum hydroxide (AH) with a D50 particle size of 60 m were mixed in a weight ratio of 40:10:30:20 (C1a:C3a:C2:AH), respectively, to prepare a filler.

Comparative Example 1

[0110] A composition was prepared as in the same method as in Example 1 above, except that aluminum hydroxide was not used, and spherical alumina (C1a) having a D50 particle size of 70 m, spherical alumina (C3a) with a D50 particle size of 20 m, and rectangular alumina (C2) with a D50 particle size of 2 m were mixed in a weight ratio of 60:20:20 (C1a:C3a:C2), respectively, to prepare a filler.

Comparative Example 2

[0111] A composition was prepared as in the same method as in Example 1 above, except that aluminum hydroxide was not used, and spherical alumina (C1a) having a D50 particle size of 70 m, rectangular alumina (C3b) with a D50 particle size of 20 m, and rectangular alumina (C2) with a D50 particle size of 2 m were mixed in a weight ratio of 60:20:20 (C1a:C3b:C2), respectively, to prepare a filler.

Comparative Example 3

[0112] A composition was prepared as in the same method as in Example 1 above, except that aluminum hydroxide was not used, and spherical alumina (C1a) with a D50 particle size of 70 m, rectangular alumina (C1b) with a D50 particle size of 70 m, spherical alumina (C3a) with a D50 particle size of 20 m, and rectangular alumina (C2) with a D50 particle size of 2 m rectangular alumina were mixed in a weight ratio of 40:20:20:20 (C1a:C1b:C3a:C2), respectively, to prepare a filler.

Comparative Example 4

[0113] A composition was prepared as in the same method as in Example 1 above, except that aluminum hydroxide was not used, and spherical alumina (C1a) with a D50 particle size of 70 m, rectangular alumina (C1b) with a D50 particle size of 70 m, rectangular alumina (C3b) with a D50 particle size of 20 m, and rectangular alumina (C2) with a D50 particle size of 2 m were mixed in a weight ratio of 40:20:20:20 (C1a:C1b:C3b:C2), respectively, to prepare a filler.

Comparative Example 5

[0114] A composition was prepared as in the same method as in Example 1 above, except that aluminum hydroxide was not used, and spherical alumina (C1a) with a D50 particle size of 70 m, spherical alumina (C3a) with a D50 particle size of 20 m, and rectangular alumina (C2) with a D50 particle size of 2 m were mixed in a weight ratio of 40:30:30 (C1a:C3a:C2), respectively, to prepare a filler.

Experimental Example 1. Measurement of Thermal Conductivity and Measurement of Thermal Conductivity Change Degree

[0115] The thermal conductivities of the cured products of the compositions of Examples 1 to 7 and the compositions of Comparative Examples 1 to 5 were compared. The compositions were each left at 25 C. for 1 hour to prepare a cured product.

[0116] The thermal conductivity of the cured product of the composition was measured by a hot disk method according to ISO 22007-2 standard. Specifically, the thermal conductivity measurement may be performed by placing the composition in a mold having a thickness of about 5 mm or so, and measuring the thermal conductivity in the thickness direction (through plane direction) using a Hot Disk device. As stipulated in the above standard, the Hot Disk device is a device that can identify the thermal conductivity by measuring the temperature change (electrical resistance change) while the sensor with a nickel wire of a double spiral structure is heated, and the thermal conductivity was measured according to such a standard.

[0117] Thereafter, the thermal conductivity change degrees of the cured products of the compositions of Examples 1 to 7 and Comparative Examples 1 to 5 were compared. Specifically, the thermal conductivity of the cured product left at room temperature for 1 hour, the thermal conductivity of the cured product left at room temperature for 5 days, and the thermal conductivity of the cured product left at room temperature for 10 days were compared, whereby the thermal conductivity change degrees were compared. The thermal conductivities after 5 days and 10 days were measured by the same method as the method for measuring a thermal conductivity as described above. The thermal conductivity change rate of the cured product left at room temperature for 10 days compared to the thermal conductivity of the cured product left at room temperature for 1 hour was calculated according to Equation 2 below.

Thermal conductivity change rate=Tc2/Tc1[Equation 2]

[0118] In Equation 2 above, Tc1 is the thermal conductivity measured after leaving the composition at room temperature (25 C.) for 1 hour, and Tc2 is the thermal conductivity measured after leaving the composition at room temperature for 10 days.

[0119] The thermal conductivities of the cured products in which the compositions of Examples 1 to 7 and Comparative Examples 1 to 5 were left at room temperature for 1 hour, the thermal conductivities of the cured products left at room temperature for 5 days, the thermal conductivities of the cured products left at room temperature for 10 days, and the thermal conductivity change rates (Tc2/Tc1) were summarized in Table 1 below.

TABLE-US-00001 TABLE 1 Thermal Thermal Thermal First filler (C1) Third filler (C3) Second Aluminum conductivity Thermal conductivity conductivity Spherical Rectangular Spherical Rectangular filler hydroxide after 1 hour conductivity after 10 days change rate (C1a) (C1b) (C3a) (C3b) (C2) (AH) (Tc1) after 5 days (Tc2) (Tc2/Tc1) (wt %) (wt %) (wt %) (wt %) (wt %) (wt %) (W/m.K) (W/m.Math.K) (W/m.K) (W/m.K) Example 1 40 20 20 20 3.18 3.22 3.23 1.02 2 35 20 20 25 3.00 3.01 3.10 1.03 3 30 40 30 3.09 3.05 3.11 1.01 4 35 30 35 3.03 3.05 3.05 1.01 5 40 20 20 20 3.28 3.53 3.45 1.05 6 20 20 20 20 20 3.44 3.40 3.42 0.99 7 40 10 30 20 3.09 3.03 3.09 1 Comparative 1 60 20 20 3.07 3.09 3.02 0.98 Example 2 60 20 20 3.15 3.19 3.07 0.97 3 40 20 20 20 3.47 3.54 3.40 0.98 4 40 20 20 20 3.26 3.53 3.45 1.06 5 40 30 30 3.10 3.12 3.09 1

Experimental Example 2. Measurement of Specific Gravity

[0120] The specific gravities of the cured products of the compositions of Examples 1 to 7 and the cured products of the compositions of Comparative Examples 1 to 5 were compared.

[0121] The specific gravity was measured according to ASTM D1475 standard. For example, after the cured product is weighed and then weighed again in water, according to the above standard, the density and specific gravity may be calculated through the difference between the measured weights, or a predetermined amount (about 5 g) of powders or pellets is put into the already-measured volume in a pyrometer and the specific gravity may be calculated through the difference between the weight and the volume at 25 C.

[0122] The specific gravities of the cured products of the compositions of Examples 1 to 7 and the cured products of the compositions of Comparative Examples 1 to 5 were summarized in Table 2 below.

TABLE-US-00002 TABLE 2 First filler (C1) Third filler (C3) Second Aluminum Spherical Rectangular Spherical Rectangular filler hydroxide (C1a) (C1b) (C3a) (C3b) (C2) (AH) Specific (wt %) (wt %) (wt %) (wt %) (wt %) (wt %) gravity Example 1 40 20 20 20 2.9 2 35 20 20 25 2.8 3 30 40 30 2.8 4 35 30 35 2.7 5 40 20 20 20 2.9 6 20 20 20 20 20 2.9 7 40 10 30 20 2.9 Comparative 1 60 20 20 3.0 Example 2 60 20 20 3.1 3 40 20 20 20 3.3 4 40 20 20 20 3.3 5 40 30 30 3.0