Corrugated fiberboard
    2.
    发明授权
    Corrugated fiberboard 失效
    CORRUGATED FIBERBOARD

    公开(公告)号:US3617429A

    公开(公告)日:1971-11-02

    申请号:US3617429D

    申请日:1969-09-26

    发明人: BLANC JOHN R LE

    摘要: Corrugated fiberboard which resists deterioration in strength when in the presence of moisture or water, and which has improved folding endurance. Such board is made by preliminarily treating medium and, optionally, liner members with a mixture of aminoplast containing phenol-aldehyde resole resin with polyvinyl alcohol (and/or with polyvinyl acetate and/or partially hydrolyzed such mixtures) and thereafter fabricating corrugated fiberboard from the so-treated members using a waterproof adhesive system containing polyvinyl alcohol, polyvinyl acetate, urea-formaldehyde, and/or phenol-aldehyde.

    Stabilized polyimides
    4.
    发明授权
    Stabilized polyimides 失效
    稳定的POLYIMIDES

    公开(公告)号:US3575891A

    公开(公告)日:1971-04-20

    申请号:US3575891D

    申请日:1968-01-02

    申请人: MONSANTO CO

    摘要: DISCLOSED HEREIN ARE RESIN SYSTEMS CHARACTERIZED BY IMPROVED OXIDATIVE THERMAL STABILITY WHICH ARE OBTAINED BY INCORPORATING A BENEFICIATING STABILIZING ADDITIVE INTO A POLYMER FORMING COMPOSITION COMPRISING (1) AROMATIC POLYCARBOXYLIC COMPONENTS CONTAINING FROM THREE TO FOUR CARBOXYLIC ACID GROUPS PER MOLECULE SELECTED FROM THE GROUP CONSISTING OF FREE POLYCARBOXYLIC ACIDS, ESTERS OF POLYCARBOXYLIC ACIDS AND AMMONIUM SALTS OF POLYCARBOXYLIC ACIDS AND (2) A POLYAMINE COMPONENT HAVING AT LEAST TWO PRIMARY AMINO GROUPS PER MOLECULE. THE BENEFICIATING STAILIZING ADDITIVES USED IN THE PRACTICE OF THE PRESENT INVENTION INCLUDE BORIC ACID, PHOSPHORIC ACID, SULFURIC ACID AND THEIR ACID DERIVATIVES AND ESTERS AND AMMONIUM SALTS OF THE FOREGOINING ACIDS.