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US 4,049,865 AGranted
Glass fibers containing a dual polyester resin size
AssigneePPG Industries, Inc.
InventorJohn Maaghul
Life of this patent
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AssigneePPG Industries, Inc.
InventorJohn Maaghul
Estimating the term…
A glass fiber sizing composition for the reinforcement of resin matrices is provided which comprises a homogeneous aqueous composition of two polyester resins. The first polyester resin is a water solubilized condensation cross-linkable, polyester resin, insoluble in aromatic solvents. The second polyester resin is insoluble but dispersible in water but insoluble in the first polyester resin. Thus, when the second polyester is blended with a water solution of the first polyester, a dispersion is produced. In this dispersion the water and the first polyester form the continuous phase and the second polyester forms the dispersed phase. A plasticizer and two silane coupling agents are also incorporated into the sizing composition. The first coupling agent is provided to promote adhesion between the glass fibers and the resin matrix and the second silane coupling agent is employed in the sizing composition to control the wetting of the glass fibers by the first silane coupling agent. A thermoplastic polymer of sufficiently low molecular weight is employed to impart pressure sensitive adhesive characteristics to the sizing composition. Glass fibers sized with the sizing composition of the invention have found particular utility when incorporated into resin matrices which are utilized as molding compounds.
Glass fibers having thereon the dried residue of a sizing composition comprising:
Glass fibers having thereon the dried residue of a sizing composition comprising 1 to 10 percent by weight of a water solubilized condensation, cross-linkable, first unsaturated polyester resin, said polyester resin substantially insoluble in aromatic solvents when crosslinked;
Dependencies are inferred from the claim text.
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From the US filing history. Foreign family members aren’t listed.
Obtained otherwise than by reactions involving only carbon-to-carbon unsaturated bonds: polyesters, e.g. alkyd resins
Using pretreated fibrous materials: glass fibres
Rod, strand, filament or fiber: coated or with bond, impregnation or core
Coated or with bond, impregnation or core: silane, silicone or siloxane in coating
Term ended 20 Sep 1994 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
This invention relates to a glass fiber sizing composition, a method of applying the sizing composition to glass fibers during formation, and glass fibers for incorporation into molding compounds.
A glass fiber strand is composed of a multitude of fine glass filaments which are formed by being drawn at a high rate of speed from molten cones of glass at the tips of small orifices in a bushing such as shown in U.S. Pat. No. 2,133,238. During formation, the filaments are coated while moving at a speed on the order of 1,524 to 6,096 meters per minute with a size which contains a binder to give the strand integrity and workability for any standard textile or reinforcement use. The size also contains a lubricant for the filaments to prevent damage to the strand by abrasion of the individual filaments against each other or against handling equipment during processing.
The attenuative force supplying the high speed drawing force to form the fine glass filaments is usually provided by a winder or a wheel puller. A winder is typically a rotating drum on which a paper tube (forming tube) is placed. As the fibers are drawn and gathered into strands, the strands are collected on the forming tube which rotates with the winder. The wheel puller, as an attenuative device, is primarily a pair of tractive, juxtaposed surfaces which pull the strand and project or direct it to a collecting apparatus.
The following examples will further elucidate the concept of the invention.
Four moles of propylene glycol, 1 mole of maleic anhydride, and 1 mole of isophthalic acid were charged to a reaction vessel equipped with a stirrer, a heating apparatus, an inert gas inlet, a thermometer to determine the temperature of the reaction and a thermometer placed at the top of a distillation column to determine the temperature of the effluent from the reaction mixture. The above ingredients were esterified to an acid value of 8.2. One mole of trimellitic anhydride was added thereto and reacted with the above formed polyester until a cure time of less than 30 seconds at 220.degree. C. was obtained. The resin was stoichiometrically neutralized with an aqueous triethyl amine solution.
The following table demonstrates the progress of the reaction: