Abstract:
The present invention provide a novel polyimide which is soluble in organic solvents and excels in heat resistance, and to a process for producing the polyimide. The polyimide of the present invention comprises a repeating unit represented by the formula (1) and having a number average molecular weight of from 4,000 to 200,000. wherein X is —SO2— or —C(═O)—OCH2CH2O—C(═O)—, and R1, R2, R3 and R4 are independently an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms.
Abstract:
A heat bond seaming tape has a base formed of a sheet of paper or a paper-like material and an overlying strip of an open mesh material. A plurality of transversely spaced, longitudinally extending beads of a hot melt thermoplastic adhesive material is placed on a top surface of the mesh for adhering the tape to the backs of adjacent carpet edges. A strip of a polyolefin such as a semi-rigid high density polyethylene material is sandwiched between the base sheet and the strip of open mesh material and extends longitudinally along the center of the strip and extends transversely across the carpet seam to prevent seam buckling. The base sheet and reinforcing strip can be extruded as an integral one piece member of the high density polyethylene prior to being joined with the mesh and hot melt adhesive.
Abstract:
A method for adhering glass products to a work surface which comprises placing adjacent to the surfaces of the pieces to be joined a continuous, non-perforated metallic foil strip, which absorbs electromagnetic waves. The strip which is contiguous with a heat activatable adhesive material, is positioned between the pieces and exposed to electromagnetic waves while the pieces are held together to form a bonded relationship between the pieces.
Abstract:
A reinforced magnetic hot patch has an attached rigid backing. The hot patch expands and flows when heated to seal an opening in a structural member. A non-planar magnetic hot patch is also provided.
Abstract:
An adhesive tape for TAB having an organic insulating film, an adhesive layer formed on the organic insulating film and a protection layer formed on the adhesive layer, the adhesive layer being any one of a layer containing a polyamide resin having an amine value of at least 3 and an epoxy resin, a layer containing a polyamide resin and a powdery inorganic filler, a layer containing an epoxy resin having a siloxane structure in its main chain, and a layer containing at least one maleimide compound.
Abstract:
An aqueous dispersion containing from 5 to 80% by weight of a copolymer A) having a glass transition temperature of from 50 to 150.degree. C. and from 95 to 20% by weight of a copolymer B) having a glass transition temperature of from -50.degree. to +50.degree. C., the glass transition temperatures of the two copolymers differing by at least 20.degree. C. at least one of the two copolymers containing from 3 to 70% by weight, based on the particular copolymer, of an ethylenically unsaturated C.sub.3 -C.sub.5 -mono- or dicarboxylic acid or of the anhydride thereof and the stated weights of the copolymers A) and B) being based on the sum of A) and B), is used as a sealable coating.
Abstract:
The invention relates to a heat-sealing adhesive, which comprises a mixture of:a) 20-60% by weight of nonadhesive (meth)acrylic acid ester-(meth)acrylic acid copolymers, which contain (meth)acrylic acid ester units with 2-8 carbon atoms in the alcohol component and, relative to these copolymers, 1-10% by weight of (meth)acrylic acid, with a melting temperature in the range of 115 to 150 and a K value according to Fikentscher in the range of 70 to 110 (measured according to DIN 51562 in tetrahydrofuran),b) 10-50% by weight of self-adhesive acrylic acid esteracrylic acid copolymers, which contain acrylic acid ester units with 2-8 carbon atoms in the alcohol component and, relative to these copolymers, 1-10% by weight of acrylic acid, with a glass transition temperature T.sub.G in the range of -45.degree. to -10.degree. C., a K value according to Fikentscher in the range of 70 to 120 (measured according to DIN 51562 in tetrahydrofuran) and a softening temperature in the range of 50.degree. to 100.degree. C., andc) 10-50% by weight of polyethylene with an average molecular weight of 1000-10000as well as optionally usual additives.It is suitable for the production of paper heat-sealing adhesive tapes, which can be used for restoration and preservation of paper substrates.
Abstract:
An improved, stable rosin ester tackifier consisting essentially of an adduct of rosin and a polyhydric alcohol selected from the group consisting of trimethylolpropane, trimethylolethane, and mixtures thereof, and hot melt adhesive compositions consisting essentially of said tackifier and a polymer component, said compositions containing a mixture of antioxidants containing a higher alkyl diester of thiopropionic acid, a hindered phenolic compound and a phenol sulfide compound, preferably an alkyl phenol disulfide oligomer.
Abstract:
Holt melt adhesive compositions having longer pot lives and comprising adhesive thermoplastic compositions having high cohesion and low flowability based on copolymers A) composed of ethylenically unsaturated monomers containing chelating metal compounds B) and, if desired, other conventional additives C), these hot melt adhesive compositions additionally containing an alkylphenolic resin or an arylphenolic resin in amounts of up to 20% by weight, relative to copolymer A), as crosslinking regulator in order to extend the pot life and to improve their processibility like a thermoplastic, and processes for preparing hot melt adhesive compositions by mixing the starting components.
Abstract:
A wetness indicating hot-melt adhesive which changes color in response to the presence of moisture is disclosed, which contains 20 to 70 wt. % of polymer, about 28 to 10 wt. % of which is water sensitive polymer; 25 to 60% of organic acid which is selected from a high acid fatty acid, or rosin acid, or a combination thereof; 0 to 40% of water soluble wax; 0 to 60 wt. % of glycerol monostearate; 0 to 55 wt. % of hydrogenated castor oil; 0 to 15 wt. % of polyalkylene wax; 0 to 60 wt. % of compatible plasticizer; and a wetness indicating agent which changes the color of the composition in response to moisture therein. The time of response of the color change can be controlled from about one second to a somewhat larger value as desired.