Minnesota Mining and Manufacturing Company

Dupont Operations Worldwide, Inc.

John A Martens

John G Chernega

Roger A Olsen

Felix P Lau

Brian H Williams

Leslie M Milner

Kurt F Feil

Auburn B Cottingham, Deceased

Burke R Blevins

Eric Daniel Morrison

William L Kausch

Lawrence M Clemens

Sudershan K Bhateja

John A Peterson

Richard J Lambert

Gary D VanDerWerff

Alvin R Zigman

Auburn B Cottinham, Deceased

Gary A Staus

Craig D Lien

The present invention is a flexographic printing plate having a very low degree of thermal distortion during development. This flexographic printing plate comprises a dimensionally stable substrate and an image bearing relief layer, wherein the thermal distortion of the flexographic printing plate in both the machine and the transverse directions is less than 0.02% when the plate is developed at temperatures in the range from about 100&deg; C. to about 180&deg; C.

Dimensionally stable flexographic printing plates

A flexographic printing plate comprising in the following order: a flexible substrate, a photohardenable composition, and a colloidal vanadium oxide antistatic layer. The antistatic layer provides protection from static induced defects until and after the flexographic plate is processed.

Flexographic printing plate having a vanadium oxide antistatic coating

A method and agent for improving polyurethane binder compositions are provided. The method comprises introducing into the polyurethane backbone a diol residue including a double bond therein. Preferably the double bond is positioned in a moiety pendant from the polyurethane backbone. In preferred compounds, the double bond-containing residue is introduced in sufficient quantities to provide at least one double bond every 2,000-3,000 molecular weight units of polymer. Preferred agents include acrylate-, methacrylate-, acrylamide-, norbornenyl- and cyclohexenyl- groups. Preferred compositions, both cured and uncured, are provided. Also, use of such a composition in magnetic recording media is described.

Magnetic recording medium comprising magnetic particles and an electron

A device for forming a flexographic printing plate is disclosed. A preformed, imagewise irradiated sheet of film is heat treated by the device of the present invention to remove unwanted portions of a top layer, leaving radiation hardened relief images on the plate. The device has a heating means for supplying heat to said film, a first delivery means for delivering a sheet of absorbent material to a surface of the film, a second delivery means for supplying film to the heating means, pressure means for causing liquified material to be absorbed onto an absorbent material, and a separation means for separating the absorbent material from the film.

Device for forming flexographic printing plate

Negative-acting flexographic printing plates display enhanced performance when backside irradiated with ionizing radiation instead of longer wavelength ultraviolet radiation. A better defined floor and more readily controlled floor is produced on the final printing plate.

Backside ionizing irradiation in a flexographic printing plate process

Negative-acting photohardenable compositions are useful in flexographic printing plate manufacture without the use of solvent development. Unhardened composition is softened and absorbed by an absorbent sheet. Absorbed composition can be removed from the sheet and recycled.

Flexographic printing plate process

A method and agent for improving polyurethane binder compositions are provided. The method comprises introducing into the polyurethane backbone a diol residue including a double bond therein. Preferably the double bond is positioned in a moiety pendant from the polyurethane backbone. In preferred compounds, the double bond-containing residue is introduced in sufficient quantities to provide at least one double bond every 2,000-3,000 molecular weight units of polymer. Preferred agents include acrylate-, methacrylate-, acrylamide-, norbornenyl-, and cyclohexenyl-groups. Preferred compositions, both cured and uncured, are provided. Also, use of such a composition in magnetic recording media is described.

Electron-beam curable polyurethane compositions; and method

Stretched surface recording disk (SSR) 10 comprising an annular support 12 having raised annular ridges 28 and 42 at its inside and outside diameters 22 and 30 with a base portion 24 in between the two ridges, and an annular recording medium film 14 held in radial tension and stretched across the base portion by adhering the film to attachment surfaces 48 and 36 near the inside and outside diameters respectively. The bond between the recording medium film and the support at the inner and outer attachment surfaces is formed by an electron beam cured adhesive such as a mixture of hydantoin hexacrylate and dimethylacrylamide. By manufacturing the stretched surface recording disks with the e-beam process, significantly less time is required to adhere each stretched recording medium to its support, and the quality of the bond between the support and recording medium film is improved. SSR are capable of higher bit density than floppy disks of equivalent surface area and are not as sensitive to contact between the media and a flying magnetic head ('head crashes') as rigid disks.

Method for making stretched surface recording disk

Magnetic recording media have been made with a new class of binder resins having the formula ##STR1## wherein the portion of the copolymer having the a subscript comprises 50 to 97 weight percent of the copolymer, the portion of the copolymer having the b subscript comprises 0 to 30 weight percent of the copolymer, the portions of the copolymer having the =c and d subscripts combined comprise 0.1 to 20 weight percent of the copolymer, while d can be 0,

Magnetic recording medium manufacturing process

Magnetic recording media have been made with a new class of binder resins having the formula ##STR1## wherein the portion of the copolymer having the a subscript comprises 50 to 97 weight percent of the copolymer, the portion of the copolymer having the b subscript comprises 0 to 30 weight percent of the copolymer, the portions of the copolymer having the c and d subscripts combinec comprise, 0.1 to 20 weight percent of the copolymer, while d can be 0,

Electron beam curable copolymer useful in recording media

Stretched surface recording disk (SSR) 10 comprising an annular support 12 having raised annular ridges 28 and 42 at its inside and outside diameters 22 and 30 with a base portion 24 in between the two ridges, and an annular recording medium film 14 held in radial tension and stretched across the base portion by adhering the film to attachment surfaces 48 and 36 near the inside and outside diameters respectively. The bond between the recording medium film and the support at the inner and outer attachment surfaces is formed by an electron beam cured adhesive such as a mixture of hydantoin hexacrylate and dimethylacrylamide. By manufacturing the stretched surface recording disks with the e-beam process, significantly less time is required to adhere each stretched recording medium to its suppport, and the quality of the bond between the support and recording medium film is improved. SSR are capable of higher bit density than floppy disks of equivalent surface area and are not as sensitive to contact between the media and a flying magnetic head ('head crashes') as rigid disks.

Stretched surface recording medium

Magnetic recording media have been made with a new class of binder resins having the formula ##STR1## wherein the portion of the copolymer having the a subscript comprises 50 to 97 weight percent of the copolymer, the portion of the copolymer having the b subscript comprises 0 to 30 weight percent of the copolymer, the portions of the copolymer having the c and d subscripts combined comprise 0.1 to 20 weight percent of the copolymer, while d can be 0,

Recording media containing alkyl acrylate copolymers

Articles prepared from radiation-curable poly(vinyl chloride) resin compositions containing an ethylenically-unsaturated compound having carbonylamino or thiocarbonylamino groups. These articles are dimensionally stable, clear, and do not exude oily materials.

Article having a coating prepared from radiation curable poly(vinyl

An article comprising a shaped, plastic layer or body comprising crosslinked polymer with hard and soft segments or moieties and having a microstructure-bearing surface is prepared by a process comprising filling a mold master, bearing or encoded with the microstructure to be replicated, with a fluid, castable, one-part, preferably solvent-free, radiation addition-polymerizable, crosslinkable, synthetic, organic oligomeric composition (or precursors thereof) having 'hard' segments and 'soft' segments, exposing the resulting cast composition to radiation, preferably actinic radiation such as ultraviolet radiation, and thereby forming said article, e.g., a retroreflective cube-corner sheeting, Fresnel lens or video disc.

Shaped plastic articles having replicated microstructure surfaces

Poly(vinyl chloride) resin compositions containing an ethylenically-unsaturated compound having carbonylamino or thiocarbonylamino groups. These compositions are readily convertible at low temperatures to crosslinked polymers and are radiation-curable to dimensionally stable articles and films that are clear and that do not exude oily materials.

Growing community of inventors

Saint Paul, MN, United States of America

John A Martens