TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The acid acceptor is chosen from magnesium hydroxide, magnesium oxide, zinc oxide, trilead tetraoxide, calcium hydroxide, aluminum hydroxide, iron hydroxide (II), calcium carbonate and hydrotalcite compound, and/or their baking products. The content of acid acceptor is 0.1-3 pts. wt. with respect to 100 pts. wt. ethylene- alpha -olefin copolymer. Preferred Properties: The diameter of an average board surface of hydrotalcite compound is 0.02-0.9 mu m. The median diameter in volume-based particle size distribution of acid acceptor is 1 mu m or less, measured by laser diffraction-scattering-type particle size distribution method. The hydrotalcite compound and/or its baking product is a compound of formula: M2+1-a.M3+a(OH)2.An(power n)(-)a/n.mH2O (I).a=0.2-0.35;m=0-5;M2+=bivalent ion chosen from Mg2+, Zn2+, Ni2+ and Ca2+, or trivalent metal ion chosen from Al3+ and Fe3+;andAn=N valent anion.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The content of organic peroxide is 0.1-3 pts. wt. with respect to 100 pts. wt. of ethylene- alpha -olefin copolymer. The organic peroxide has 1-minute half life temperature of 100-170 degrees C. The solar cell-sealing material further contains silane coupling agent. The content of silane coupling agent is 0.1-5 pts. wt. with respect to 100 pts. wt. ethylene- alpha -olefin copolymer. Preferred Property: 1-minute half life temperature of organic peroxide is 100-170 degrees C.    TECHNOLOGY FOCUS - POLYMERS - Preferred Composition: The content of structural unit derived from ethylene in ethylene- alpha -olefin copolymer is 80-90 mol%. The content of structural unit derived from 3-20C alpha -olefin in ethylene- alpha -olefin copolymer is 10-20 mol%. Preferred Properties: The ethylene- alpha -olefin copolymer has melt-flow rate of 10-50 g/10 minutes, preferably 10-27 g/10 minutes, at 190 degrees C under load of 2.16 kg, based on ASTM D1238, density of 0.865-0.884 g/cm3, based on ASTM D1505, and Shore A hardness of 60-85, based on ASTM D2240. Preferred Process: The solar cell-sealing material is obtained by mixing ethylene- alpha -olefin copolymer, organic peroxide, and acid acceptor, and molding in a sheet form.