Minnesota Mining and Manufacturing Company

3m Innovative Properties Company

John D Moon

George F Vesley

Louise A Ziegler

James J Kobe

Craig E Hamer

Shih-Lai Lu

Forrest J Rouser

Robert V Heiti

Thomas A Kotnour

Thomas E Boettcher

Michael K Martin

Maurice E Freeman

Mark S Edberg

Robert D Anderson

Robert C Mehner

Francis M Stark

Steven M Heilmann

Cheryl L Moore

Margaret M Sheridan

William J Traynor

Disclosed is a novel, multi-stage irradiation process for the production of an acrylic-based adhesive or pressure-sensitive adhesive tape. The first irradiation step or stage employs electromagnetic radiation at a relatively low average intensity (i.e., 0.1 to 20 mW/cm ) and the subsequent step employs electromagnetic radiation at a relatively higher average intensity (i.e., greater than 20 mW/cm .) Also disclosed are acrylic-based psa tape materials made by the novel process.

Multi-stage irradiation process for production of acrylic based adhesives and adhesives made thereby

Methods for preparing viscoelastic compositions (e.g., adhesives such as hot melt adhesives) in which a pre-viscoelastic composition (e.g., a pre-adhesive composition) is combined with a packaging material and then polymerized.

Packaged pre-adhesive composition

Disclosed is a novel, multi-stage irradiation process for the production of acrylic-based compositions such as adhesives or pressure-sensitive adhesive tapes. The first irradiation step or stage employs electromagnetic radiation at a relatively low average intensity (i.e., 0.1 to 20 mW/cm,) to effect a relatively low extent of monomer conversion, and the subsequent step employs electromagnetic radiation at a relatively higher average intensity (i.e., greater than 20 mW/cm,) to complete the photopolymerization. Also disclosed are acrylic-based psa tape materials made by the novel process.

Multi-stage irradiation process for production of acrylic based compositions and compositions made thereby

Methods of making packaged viscoelastic compositions

Methods for preparing viscoelastic compositions (e.g., adhesives such as hot melt adhesives) in which a pre-viscoelastic composition (e.g., a pre-adhesive composition) is combined with a packaging material and then polymerized by transmissive energy.

A reclosable mechanical fastener comprising a fastening component having a surface structure by which two such fastening components can become releasably attached. The novel fastening component is a composite of a tough substrate and a fastening layer that forms said surface structure, which fastening layer is formed from a cured oligomeric resin composition having one or more like or different hard segments, one or more like or different soft segments, and one or more like or different monovalent moieties containing a radiation-sensitive, addition-polymerizable, function group. The novel fastener forms stronger linkages than were possible with similar fasteners of the prior art.

Reclosable mechanical fastener based on a composite article

A pressure-sensitive adhesive is provided. The adhesive comprises (a) about 50 to 95 weight percent of an ultraviolet radiation polymerized polymer of (i) one or more monomers which are predominantly alkyl acrylate, the alkyl groups of which have an average of 4 to 12 carbon atoms and (ii) about 0 to 15 weight percent of one or more strongly polar copolymerizable monomers or about 0 to 30 weight percent of one or more moderately polar copolymerizable monomers; and (b) about 5 to 50 weight percent of one or more tackifying resins. The tackifying resins are aromatic polymeric resins which have a number average molecular weight of about 300 to 2500, a polydispersity index of less than about 5, a glass transition temperature of about 40.degree. to 120.degree. C., and a solubility parameter of about 7 to 9.5 (cal/cc).sup.-1/2. The adhesive has a monomer conversion factor off at least 98%, and has good storage stability, i.e., losing no more than 70% of its adhesion when aged for a period of two weeks at 70.degree. C.

Pressure-sensitive adhesive

An acrylic terpolymer pressure-sensitive adhesive comprising a photopolymerized polymer containing an alkyl acrylate monomer, the alkyl groups of which have an average of 6 to 12 carbon atoms, a first polar copolymerizable monomer selected from strongly polar monomers, and a second polar monomer selected from the group consisting of strongly polar monomers and moderately polar monomers, a hydrogenated rosin ester tackifying agent, and a photoinitiator, wherein the adhesive has a lower glass transition temperature as measured by Dynamic Mechanical Thermal Analysis than would an identical acrylic terpolymer adhesive omitting the tackifying agent.

Tackified terpolymer adhesives

A pressure-sensitive adhesive that has high cohesive strength and adheres permanently to high-solids automotive paint systems preferably comprises a mixture of (1) a crosslinked acrylic copolymer of acrylic acid ester and N-vinyl-2-pyrrolidone, and (2) certain tackifier resins. Useful tackifier resins are poly(isobornylmethacrylate), pentaerythritol ester of rosin, and mixed-aliphatic/aromatic polymeric tackifier resins such as a t-butylated styrene. The tackifier resin preferably has a T.sub.g of at least 30.degree. C., M.sub.n from 300 to 3000, and a solubility parameter from 8 to 9. The novel pressure-sensitive adhesive is particularly useful as a dense surface layer of a composite tape having a foamlike core.

Tackified acrylic pressure-sensitive adhesive and composite article

Pressure-sensitive adhesive tape having a photopolymerized acrylate polymer adhesive which has been crosslinked by a polyacrylic-functional crosslinking monomer such as trimethyol-propane triacrylate.

Multiacrylate cross-linking agents in pressure-sensitive photoadhesives

Pressure-sensitive adhesive tape which has both high adhesion and high cohesion values and adheres strongly to automotive paints and to rubber or plastic foam layers, thus showing great promise for adhering plastic molding strips to the sides of automobiles. The adhesive layer of the novel tape may be made by photopolymerizing (1) acrylic acid ester of non-tertiary alcohol, the alkyl groups of which have an average of 4-14 carbon atoms and (2) N-vinyl-2-pyrrolidone in an amount within 15-50 parts by weight of the total monomers (1) and (2), preferably 25-35 parts.

Pressure-sensitive adhesive copolymers of acrylic acid ester and N-vinyl

Pressure-sensitive adhesive tape, the adhesive layer of which is produced from a mixture of (1) a pressure-sensitive adhesive alkyl acrylate polymer and (b) a polynuclear-chromophore-substituted halomethyl-s-triazine such as ##STR1## which has been exposed to ultraviolet radiation to cause the polymer to become crosslinked.

Growing community of inventors

Hastings, MN, United States of America

John D Moon