USRE39307EExpiredUtility

Hot-melt adhesive having improved bonding strength

82
Assignee: KIMBERLY CLARK COPriority: Dec 29, 2000Filed: Nov 24, 2004Granted: Sep 26, 2006
Est. expiryDec 29, 2020(expired)· nominal 20-yr term from priority
Inventors:Peiguang Zhou
C09J 123/02B32B 2305/20C09J 153/00C08L 2666/04B32B 2307/51C09J 153/02B32B 5/02B32B 2037/1215C09J 123/10C09J 123/12B32B 5/04B32B 5/26C08L 23/10C08L 2205/02C09J 123/142B32B 7/12B32B 25/04C08L 2207/14B32B 37/12C09J 123/14C09J 123/20Y10T442/2738Y10T442/2787Y10T428/192Y10T428/31855Y10T442/2746Y10T442/2754
82
PatentIndex Score
13
Cited by
185
References
28
Claims

Abstract

Hot-melt, pressure-sensitive adhesive compositions of amorphous polyalphaolefin and crystalline polypropylene have improved bond strength over the amorphous polyalphaolefin alone. The adhesive compositions improve dynamic shear strength, dynamic peel strength, as well as static peel strength. The adhesive compositions are particularly suitable for use in absorbent articles.

Claims

exact text as granted — not AI-modified
1. A pressure sensitive hot melt adhesive composition comprising from about 70% to about 90% amorphous polyalphaolefin and from about 10% to about 30% crystalline polypropylene having a degree of crystallinity of at least about 40%, said  the amorphous polyalphaolefin comprising a butene- 1 terpolymer with ethylene and propylene  copolymer and having a number - average molecular weight between about  5 , 000  and about  30 , 000  and a weight - average molecular weight between about  20 , 000  and about  60 , 000 , the crystalline polypropylene having a number - average molecular weight between about  10 , 000  and about  100 , 000  and a weight - average molecular weight between about  20 , 000  and about  300 , 000 , and wherein the adhesive composition has a melt index between about  200  and about  2000  grams per  10  minutes as determined by ASTM D  1238 .   
     
     
       2. The adhesive composition of  claim 1 , comprising between about 73% and about 87% of the amorphous polyalphaolefin, and between about 13% and about 27% of the crystalline polypropylene. 
     
     
       3. The adhesive composition of  claim 1 , comprising between about 75% and about 85% of the amorphous polyalphaolefin, and between about 15% and about 25% of the crystalline polypropylene. 
     
     
       4. The adhesive composition of  claim 1 , wherein the degree of crystallinity of the crystalline polypropylene is at least about 60%. 
     
     
       5. The adhesive composition of  claim 1 , wherein the degree of crystallinity of the crystalline polypropylene is at least about 80%. 
     
     
       6. The adhesive composition of  claim 1 , wherein the amorphous polyalphaolefin has a number-average molecular weight between about 5,000 and about 30,000. 
     
     
       7. The adhesive composition of  claim 1 , wherein the amorphous polyalphaolefin has a weight-average molecular weight between about 20,000  25,000 and about 60,000  50,000. 
     
     
       8. The adhesive composition of  claim 1 , wherein the crystalline polypropylene has a number-average molecular weight between about 3,000 and about 200,000. 
     
     
       9. The adhesive composition of  claim 1 , wherein the crystalline polypropylene has a number-average molecular weight between about 10,000 and about 100,000. 
     
     
       10. The adhesive composition of  claim 1 , wherein the adhesive composition has a melt index between about 200 and about 2000 grams per 10 minutes. 
     
     
       11. The adhesive composition of  claim 1 , wherein the adhesive composition has a melt index between about 400 and about 1800 grams per 10 minutes. 
     
     
       12. The adhesive composition of  claim 1 , wherein the adhesive composition has a melt index between about 500 and about 1500 grams per 10 minutes. 
     
     
       13. The adhesive of  claim 1  wherein the butene- 1 terpolymer  copolymer  comprises between about 20% and about 65% by weight butene- 1, and a balance of a comonomer selected from the group consisting of ethylene, propylene, and combinations thereof.   
     
     
       14. The adhesive of  claim 1  wherein the butene- 1 terpolymer  copolymer  comprises between about 30% and about 55% by weight butene- 1, and a balance of a comonomer selected from the group consisting of ethylene, propylene, and combinations thereof.   
     
     
       15. The adhesive composition of  claim 1 , wherein the crystalline polypropylene comprises at least one of the group consisting of isotactic polypropylene, syndiotactic polypropylene, and combinations thereof. 
     
     
       16. The adhesive composition of  claim 1  wherein the crystalline polypropylene has a melt index of about  1000  grams per  10  minutes as determined by ASTM D  1238 . 
     
     
       17. A pressure sensitive hot melt adhesive composition comprising from about  70 %  to about  90   %  amorphous polyalphaolefin and from about  10   %  to about  30   %  crystalline polypropylene having a degree of crystallinity of at least about  40   % , the amorphous polyalphaolefin comprising a butene -   1  terpolymer with ethylene and propylene and having a number - average molecular weight between about  5 , 000  and about  30 , 000  and a weight - average molecular weight between about  20 , 000  and about  60 , 000 , the crystalline polypropylene having a number - average molecular weight between about  10 , 000  and about  100 , 000  and a weight - average molecular weight between about  20 , 000  and about  300 , 000 , and wherein the adhesive composition has a melt index between about  200  and about  2000  grams per  10  minutes as determined by ASTM D  1238 .   
     
     
       18. The adhesive composition of  claim 17 , comprising between about  73 %  and about  87   %  of the amorphous polyalphaolefin, and between about  13   %  and about  27   %  of the crystalline polypropylene.   
     
     
       19. The adhesive composition of  claim 17 , comprising between about  75 %  and about  85   %  of the amorphous polyalphaolefin, and between about  15   %  and about  25   %  of the crystalline polypropylene.   
     
     
       20. The adhesive composition of  claim 17 , wherein the degree of crystallinity of the crystalline polypropylene is at least about  60 %. 
     
     
       21. The adhesive composition of  claim 17 , wherein the degree of crystallinity of the crystalline polypropylene is at least about  80 %. 
     
     
       22. The adhesive composition of  claim 17 , wherein the amorphous polyalphaolefin has a weight- average molecular weight between about  25 , 000  and about  50 , 000 .   
     
     
       23. The adhesive composition of  claim 17 , wherein the adhesive composition has a melt index between about  400  and about  1800  grams per  10  minutes as determined by ASTM D  1238 . 
     
     
       24. The adhesive composition of  claim 17 , wherein the adhesive composition has a melt index between about  500  and about  1500  grams per  10  minutes as determined by ASTM D  1238 . 
     
     
       25. The adhesive of  claim 17  wherein the butene-   1  terpolymer comprises between about  20   %  and about  65   %  by weight butene -   1 .   
     
     
       26. The adhesive of  claim 17  wherein the butene-   1  terpolymer comprises between about  30   %  and about  55   %  by weight butene -   1 .   
     
     
       27. The adhesive composition of  claim 17 , wherein the crystalline polypropylene comprises at least one of the group consisting of isotactic polypropylene, syndiotactic polypropylene, and combinations thereof. 
     
     
       28. The adhesive composition of  claim 17  wherein the crystalline polypropylene has a melt index of about  1000  grams per  10  minutes as determined by ASTM D  1238 .

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