| 摘要 |
1. A substantially anhydrous blowing agent obtained by treating a blowing agent with a surface-treating agent capable of removing water from the blowing agent in which a blowing agent is crystalline azodicarbonamide. 2. The substantially anhydrous blowing agent according to claim 1, wherein the surface-treating agent is at least one selected from the group consisting of a coupling agent, an organic acid anhydride, an anhydrous inorganic compound, and a desiccant. 3. The substantially anhydrous blowing agent according to claim 2, wherein the surface-treating agent is at least one selected from the group consisting of a silane coupling agent, an aluminum coupling agent, and a titanate coupling agent. 4. The substantially anhydrous blowing agent according to claim 3, wherein the surface-treating agent is an aluminum coupling agent, and the surface of the blowing agent is coated with aluminum hydroxide. 5. A process for producing a substantially anhydrous blowing agent, which comprises treating a blowing agent with a surface-treating agent capable of removing water from the blowing agent under conditions substantially free of a solvent, wherein the blowing agent is crystalline azodicarbonamide. 6. The process according to claim 5, wherein heating treatment is carried out during or after the treatment with the surface-treating agent. 7. The process according to claim 6, wherein the heating treatment is carried out at a temperature of 30 degree C to the decomposition temperature of the blowing agent. 8. The process according to claim 7, wherein the heating is carried out at a temperature of 55 to 100 degree C. 9. The process according to any one of claims 6 to 8, wherein the surface-treating agent is subjected to preheating treatment. 10. The process according to any one of claims 6 to 9, wherein the treatment of the blowing agent with the surface-treating agent is carried out by spraying the surface-treating agent to the blowing agent, and mixing them under mixing conditions where pulverization of a blowing agent is inhibited. 11. The process according to claim 10, wherein a ribbon blender or a screw mixer is used as a mixer under the mixing conditions where pulverization of a blowing agent is inhibited. 12. The process according to any one of claims 5 to 11, wherein the surface-treating agent is at least one selected from the group consisting of a coupling agent, an organic acid anhydride, an anhydrous inorganic compound, and a desiccant. 13. The process according to claim 12, wherein the surface-treating agent is at least one selected from the group consisting of a silane coupling agent, an aluminum coupling agent, and a titanate coupling agent. 14. The process according to claim 13, wherein the surface-treating agent is selected from the group consisting of aluminum isopropylate, aluminum ethylate, aluminum tris(ethylacetoacetate), and ethylacetoacetatoaluminum diisopropylate. |
