Claims
- 1. A method of strengthening a scored corrugated board product formed from a plurality of substrates, comprising the steps of:
- (a) prior to adhering a substrate having a score comprising corrugated flutes adhered to a first liner sheet to a second substrate comprising a second liner sheet, with the flutes positioned between the first and second liner sheets, inserting a pair of generally linearly extending strengthening filaments, one on either side of the score, between the substrates, with the filaments spaced from, and running generally parallel to, the score; and
- (b) prior to adhering the two adjacent substrates together, inserting a serpenting filament, sinuating generally sinusoidally across, and intersecting, the pair of generally linearly extending strengthening filaments, between the substrates, the serpentine filament being bonded to the pair of strengthening filaments.
- 2. A method in accordance with claim 1 further comprising the steps of:
- (c) coating at least some of the filaments with a thermoplastic adhesive having a measure of cold flow under pressure prior to inserting them between the substrates; and
- (d) bonding the filaments together at said points of intersection to form an integrated network prior to inserting them between the substrates.
- 3. A method in accordance with claim 2 wherein the bonding step including subjecting said points of intersection to pressure to cause flow of said thermoplastic adhesive.
- 4. A method in accordance with claim 3 wherein said intersecting filament network is fed through a dual cylinder wringer-type assembly to subject said points of intersection to pressure.
Parent Case Info
This is a division of application Ser. No. 322,893, filed Nov. 19, 1981, U.S. Pat. No. 4,451,515.
US Referenced Citations (16)
Non-Patent Literature Citations (1)
Entry |
Copy of Brochure "String King System" (H. B. Fuller). |
Divisions (1)
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Number |
Date |
Country |
Parent |
322893 |
Nov 1981 |
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