Adhesive composition and sheet-like product formed therewith
AssigneeMinnesota Mining and Manufacturing Company
InventorWayne A. Pletcher
Life of this patent
Estimating the term…
Abstract
A method for forming a strong bond between a substrate and a solid thermoplastic polymer which comprises melting a thermoplastic polymer having an effective open time (a period after melting the polymer during which it remains aggressively tacky and bondable below the melting temperature), cooling it below the melting temperature, contacting the open polymer with a substrate and allowing the polymer to revert to its non-bondable, solid state. Also disclosed are a class of copolyesters suitable for use in the method and certain novel articles adapted for carrying out the method.
Claims34
A sheet backing provided on at least one major surface with a thermoplastic, coherent layer which essentially comprises a segmented copolyester capable of forming a strong, dependable bond to a substrate at a temperature below its melting temperature and without the involvement of volatiles consisting essentially of from about 5 to 75 percent by weight of amorphous ester units and 95 to 25 percent by weight of crystallizable ester units joined through ester linkages, the crystallizable ester units being of the formula:
- ##STR5## and the amorphous ester units being of the formula:
- ##STR6## wherein R.sub.1 consists of residues of one or more diacids selected from saturated aliphatic dicarboxylic acids containing from 4 to 10 carbon atoms and aromatic dicarboxylic acids selected from terephthalic acid, isophthalic acid, phthalic acid, 4,4'-benzophenone dicarboxylic acid, 4,4'-diphenylmethane dicarboxylic acid, 4,4'-diphenylether dicarboxylic acid, 4,4'-diphenylthioether dicarboxylic acid and 4,4'-diphenylamine dicarboxylic acid, R.sub.2 consists of residues of one or more saturated aliphatic diols containing from 2 to 12 carbon atoms, R.sub.3 is R.sub.1 or R.sub.5, R.sub.4 is R.sub.2 or R.sub.6, R.sub.5 consists of the divalent radicals containing from about 22 to 50 carbon atoms which remain after removal of the carboxyl groups from saturated aliphatic dimer acids and R.sub.6 consists of the divalent radicals remaining after removal of the hydroxyl groups of long chain aliphatic diols having an average molecular weight of 200 to 4000, provided that at least one of R.sub.3 and R.sub.4 in each amorphous ester unit is R.sub.5 or R.sub.6, and provided that when R.sub.1 is aromatic, R.sub.2 contains from 6 to 12 carbon atoms and the amorphous content is 50-75 percent by weight, the said copolyester having a DTA melting temperature of from about 25.degree. to 150.degree. C., an inherent viscosity of at least 0.5 dl/g at 25.degree. C., as measured in 0.3 g/dl solutions of polymer in chloroform at 25.degree. C., an open time of at least about 1/4 minute at 20.degree. C., substantially complete solubility in toluene at 25.degree. C. in the ratio of about 10 percent by weight of copolyester and 90% by weight of solvent, a tensile strength of 100-400 kg/cm.sup.2, an elongation at break of 400-1000 percent, a T-peel adhesion to vinyl of at least 0.9 kg/cm of width and a DTA glass transition temperature, T.sub.g, below -25.degree. C.
A composite tape-like product capable of being wound upon itself in roll form and subsequently unwound without delamination or transfer comprising a flexible sheet backing having adhered thereto over one major surface a thermoplastic, coherent layer which essentially comprises a segmented copolyester capable of forming a strong, dependable bond to a substrate at a temperature below its melting temperature and without the involvement of volatiles consisting essentially of from about 5 to 75 percent by weight of amorphous ester units and 95 to 25 percent by weight of crystallizable ester units joined through ester linkages, the crystallizable ester units being of the formula:
- ##STR7## and the amorphous ester units being of the formula:
- ##STR8## wherein R.sub.1 consists of residues of one or more diacids selected from saturated aliphatic dicarboxylic acids containing from 4 to 10 carbon atoms and aromatic dicarboxylic acids selected from terephthalic acid, isophthalic acid, phthalic acid, 4,4'-benzophenone dicarboxylic acid, 4,4'-diphenylmethane dicarboxylic acid, 4,4'-diphenylether dicarboxylic acid, 4,4'-diphenylthioether dicarboxylic acid and 4,4'-diphenylamine dicarboxylic acid, R.sub.2 consists of residues of one or more saturated aliphatic diols containing from 2 to 12 carbon atoms, R.sub.3 is R.sub.1 or R.sub.5, R.sub.4 is R.sub.2 or R.sub.6, R.sub.5 consists of the divalent radicals containing from about 22 to 50 carbon atoms which remain after removal of the carboxyl groups from saturated aliphatic dimer acids and R.sub.6 consists of the divalent radicals remaining after removal of the hydroxyl groups of long chain aliphatic diols having an average molecular weight of 200 to 4000, provided that at least one of R.sub.3 and R.sub.4 in each amorphous ester unit is R.sub.5 or R.sub.6, and provided that when R.sub.1 is aromatic, R.sub.2 contains from 6 to 12 carbon atoms and the amorphous content is 50-75 percent by weight, the said copolyester having a DTA melting temperature of from about 25 to 150.degree. C., an inherent viscosity of at least 0.5 dl/g at 25.degree. C., as measured in 0.3 g/dl solutions of polymer in chloroform at 25.degree. C., an open time of at least about 1/4 minute at 20.degree. C., substantially complete solubility in toluene at 25.degree. C. in the ratio of about 10 percent by weight of copolyester and 90% by weight of solvent, a tensile strength of 100-400 kg/cm.sup.2, an elongation at break of 400-1000 percent, a T-peel adhesion to vinyl of at least 0.9 kg/cm of width and a DTA glass transition temperature, T.sub.g, below -25.degree. C.
A fiber-reinforced thermoplastic adhesive film comprising in combination a fibrous web provided on at least one major surface with a thermoplastic segmented copolyester capable of forming a strong, dependable bond to a substrate at a temperature below its melting temperature and without the involvement of volatiles consisting essentially of from about 5 to 75 percent by weight of amorphous ester units and 95 to 25 percent by weight of crystallizable ester units joined through ester linkages, the crystallizable ester units being of the formula:
- ##STR9## and the amorphous ester units being of the formula:
- ##STR10## wherein R.sub.1 consists of residues of one or more diacids selected from saturated aliphatic dicarboxylic acids containing from 4 to 10 carbon atoms and aromatic dicarboxylic acids selected from terephthalic acid, isophthalic acid, phthalic acid, 4,4'-benzophenone dicarboxylic acid, 4,4'-diphenylmethane dicarboxylic acid, 4,4'-diphenylether dicarboxylic acid, 4,4'-diphenylthioether dicarboxylic acid and 4,4'-diphenylamine dicarboxylic acid, R.sub.2 consists of residues of one or more saturated aliphatic diols containing from 2 to 12 carbon atoms, R.sub.3 is R.sub.1 or R.sub.5, R.sub.4 is R.sub.2 or R.sub.6, R.sub.5 consists of the divalent radicals containing from about 22 to 50 carbon atoms which remain after removal of the carboxyl groups from saturated aliphatic dimer acids and R.sub.6 consists of the divalent radicals remaining after removal of the hydroxyl groups of long chain aliphatic diols having an average molecular weight of 200 to 4000, provided that at least one of R.sub.3 and R.sub.4 in each amorphous ester unit is R.sub.5 or R.sub.6, and provided that when R.sub.1 is aromatic, R.sub.2 contains from 6 to 12 carbon atoms and the amorphous content is 50-75 percent by weight, the said copolyester having a DTA melting temperature of from about 25.degree. to 150.degree. C., an inherent viscosity of at least 0.5 dl/g at 25.degree. C., as measured in 0.3 g/dl solutions of polymer in chloroform at 25.degree. C. and an open time of at least about 1/4 minute at 20.degree. C., substantially complete solubility in toluene at 25.degree. C. in the ratio of about 10 percent by weight of copolyester and 90% by weight of solvent, a tensile strength of 100-400 kg/cm.sup.2, an elongation at break of 400-1000 percent, a T-peel adhesion to vinyl of at least 0.9 kg/cm of width and a DTA glass transition temperature, T.sub.g, below -25.degree. C.
A thermoplastic segmented copolyester capable of forming a strong, dependable bond to a substrate at a temperature below its melting temperature and without the involvement of volatiles consisting essentially of from about 5 to 75 percent by weight of amorphous ester units and 95 to 25 percent by weight of crystallizable ester units joined through ester linkages, the crystallizable ester units being of the formula:
- ##STR11## and the amorphous ester units being of the formula:
- ##STR12## wherein R.sub.1 consists of residues of one or more diacids selected from saturated aliphatic dicarboxylic acids containing from 4 to 10 carbon atoms and aromatic dicarboxylic acids selected from terephthalic acid, isophthalic acid, phthalic acid, 4,4'-benzophenone dicarboxylic acid, 4,4'-diphenylmethane dicarboxylic acid, 4,4'-diphenylether dicarboxylic acid, 4,4'-diphenylthioether dicarboxylic acid and 4,4'-diphenylamine dicarboxylic acid, R.sub.2 consists of residues of one or more saturated aliphatic diols containing from 2 to 12 carbon atoms, R.sub.3 is R.sub.1 or R.sub.5, R.sub.4 is R.sub.2 or R.sub.6, R.sub.5 consists of the divalent radicals containing from about 22 to 50 carbon atoms which remain after removal of the carboxyl groups from saturated aliphatic dimer acids and R.sub.6 consists of the divalent radicals remaining after removal of the hydroxyl groups of long chain aliphatic diols having an average molecular weight of 200 to 4000, provided that at least one of R.sub.3 and R.sub.4 in each amorphous ester unit is R.sub.5 or R.sub.6, and provided that when R.sub.1 is aromatic, R.sub.2 contains from 6 to 12 carbon atoms and the amorphous content is 50-75 percent by weight, the said copolyester having a DTA melting temperature of from about 25.degree. to 150.degree. C., an inherent viscosity of at least 0.5 dl/g at 25.degree. C., as measured in 0.3 g/dl solutions of polymer in chloroform at 25.degree. C., an open time of at least about 1/4 minute at 20.degree. C., substantially complete solubility in toluene at 25.degree. C. in the ratio of about 10 percent by weight of copolyester and 90% by weight of solvent, a tensile strength of 100-400 kg/cm.sup.2, an elongation at break of 400-1000 percent, a T-peel adhesion to vinyl of at least 0.9 kg/cm of width and a DTA glass transition temperature, T.sub.g, below -25.degree. C.
Dependencies are inferred from the claim text.