A COMPOSITION FOR AN COMPOSITE SHEET WITH ENHANCED HEAT-RELEASING AND ELECTROMAGNETIC WAVE SHIELDING/ABSORBING PROPERTIES, AND A COMPOSITE SHEET WITH ENHANCED HEAT-RELEASING AND ELECTROMAGNETIC WAVE SHIELDING/ABSORBING PROPERTIES AND A METHOD FOR PREPARATION THEREOF

摘要

as The present invention provides a composition for electromagnetic shielding and heat dissipation / absorption characteristics are superior composite sheet, the proportion 1.05~ 1.10 The hardness of 35~45 Shore A supplemental two-component liquid silicone resin to 100 parts by weight; A viscosity of 3.7 to 4.5 centipoise (cP) 10 to 30 parts by weight of a liquid silicone oil; Each of the particle size distribution 4~6, 8~12 and three spherical alumina are mixed in 40~50 () 40 to 60 parts by weight of alumina powder; The average particle diameter of the spherical 1.0~1.5 () aluminum hydroxide (Al (OH) ₃ ) 20 to 30 parts by weight of powder; 5~6 density and particle size, and compression (compressed density) is 3.3~4.1 g / a flake () or irregularly shaped nickel-zinc ferrite (Ni-Zn ferrite) or manganese-zinc ferrite (Mn- Zn ferrite) relates to a composition comprising 250 to 350 weight parts of powder. ; The present invention is a method for manufacturing a thermal and electromagnetic shielding / absorbing properties are excellent composite sheet, (a) silver, copper, nickel, gold, aluminum, silver coated copper, silver coated nickel , silver coated aluminum, and aluminum-coated onto a fiber mesh or fabric is an electrically conductive material are selected from the group consisting of nickel-coated to form a conductive layer (10); And (b) a specific gravity of 1.05 to 1.10 and a hardness of 35~45 Shore A two-component addition-type liquid silicone resin of 100 parts by weight; A viscosity of 3.7 to 4.5 centipoise (cP) 10 to 30 parts by weight of a liquid silicone oil; Each of the particle size distribution 4~6, 8~12 and three spherical alumina are mixed in 40~50 () 40 to 60 parts by weight of alumina powder; The average particle 1.0~1.5 initiative in diameter () aluminum hydroxide (Al (OH) ₃ ) 20 to 30 parts by weight of powder; 5~6 density and particle size, and compression (compressed density) is 3.3~4.1 g / a flake () or irregularly shaped nickel-zinc ferrite (Ni-Zn ferrite) or manganese-zinc ferrite (Mn- Zn ferrite) powder 250 to 350 parts by weight and mixed homogeneously to prepare a slurry (slurry), removing the air bubbles using a deaerator, the said uniform slurry cast molding method to one or both sides of the conductive layer 10 a method comprising the step of forming a heat and electromagnetic shielding / absorbing layer 20 by coating. In addition, the present invention provides a prepared heat and electromagnetic wave shielding / absorbing properties are excellent composite sheet according to the above method, the conductive layer 10, heat radiation and electromagnetic shielding on one or both sides of a / absorbing layer 20 and are stacked, ASTM D5470 and the thermal conductivity is measured by the method 1.15 W / m K or more, the electromagnetic wave shielding ratio of 61~70 dB ASTM D4935-99, measured at a frequency of 30~1000MHz by the method, by the method of KS C0305 1.27MHz Specific absorption rate is measured at a frequency related to a composite sheet, characterized in that the -10.5 dB.