| 配方类型： |
ADHESIVES |
| 配方说明： |
Delayed-Tack Adhesives |
| 配制方法： |
These preparations, after they are spread and dried on a surface, are normally tack-free at ordinary temperatures. They are activated by heat and maintain their tackiness over a fairly wide temperature range from several minutes to several days. This permits the necessary handling, while two surfaces are being united, before the adhesive becomes nontacky by cooling and setting. Thus, the action of delayed-tack adhesives differs from that of hot-melt adhesives where tackiness terminates on cooling alone.
Solid plasticizers, such as diphenyl phthalate and "Santicizers" 1-h and 9, confer "delayed tack" on these adhesives. Plasticizers are selected according to their effect on the base resin, i.e., the temperatures att which the adhesiveness is activated and deactivated and their heat and light stability, odor, nontoxicity-where required, etc. Much of this art is described in the patent literature (for example, United States patents 2,462,029; 2,608,542; 2,608 543; 2,613,156 and 2,613,191) which should be in |
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