Showing papers by "3M published in 1987"

Polysiloxane-grafted copolymer pressure sensitive adhesive composition and sheet materials coated therewith

Abstract: This invention provides pressure sensitive adhesive (PSA) compositions comprising a copolymer having a vinyl polymeric backbone having grafted thereto polysiloxane moieties. The compositions may contain other ingredients such as tackifier and/or plasticizer. An exposed surface of the PSA composition is initially positionable on a substrate to which it will be adhered but, once adhered, builds adhesion to form a strong bond. The PSA compositions may be used alone or in blends with unsiliconized PSA compositions. The invention also provides sheet materials coated with the PSA composition such as tape, labels, etc.

Bicomponent fibers and webs made therefrom

Abstract: Biocomponent fibers, and webs made therefrom, are taught in which one component of the fibers is a crystallizable material. When a web of the fibers is heated in a mold above the temperature at which crystallization occurs, the fibers tend to be set in the position they are held in the mold. A preferred fiber comprises blown fibers comprising as one component amorphous, crystallizable polyethylene terephthalate, and as the other component polypropylene. A web of such fibers not only becomes formed into a shape-retaining form by crystallization during the molding process, but also can be further established in its shape-retaining character by heating the web above the softening point of the polypropylene, whereupon the fibers become bonded at their points of intersection.

Block copolymer, method of making the same, diamine precursors of the same, method of making such diamines and end products comprising the block copolymer

Abstract: Block copolymers having a repeating unit comprised of polysiloxane and urea segments are prepared by copolymerizing certain diaminopolysiloxanes with diisocyanates. The invention also provides novel diaminopolysiloxanes useful as precursors in the preparation of the block copolymers and a method of making such diaminopolysiloxanes. Pressure sensitive adhesive compositions comprising the block copolymer are also provided as are sheet materials coated with the same.

Pressure-sensitive adhesive crosslinked by copolymerizable aromatic ketone monomers

Abstract: A pressure-sensitive adhesive is provided which is a copolymer of an acrylate monomer which contributes to the visco-elastic properties of the copolymer and a copolymerizable mono-ethylenically unsaturated aromatic ketone comonomer free of ortho-aromatic hydroxyl groups by means of which the copolymer can be crosslinked upon exposure to ultraviolet radiation such that the amount of crosslinking comonomer and the degree of polymerization of the copolymer are controlled to obtain a creep compliance value of at least about 1.2×10 -5 cm 2 /dyne, the adhesive exhibits an enhanced level of initial adhesion when applied to skin but resists objectionable adhesion build-up over time. A preferred crosslinking ethylenically unsaturated hydroxyl-free aromatic ketone comonomer is p-acryloxybenzophenone.

Coated abrasive having radiation curable binder

Abstract: Coated abrasive product and a process for producing same. The coated abrasive product comprises a backing, a make coat, and a size coat, and may contain an optional saturant coat, an optional presize coat, an optional backsize coat, or any combination of said optional coats, in which at least one coat is formed from a composition curable by electromagnetic radiation comprising: (A) a curable portion containing both ethylenically unsaturated groups and 1,2-epoxide groups, which groups can be in the same compound or in different compounds, and (B) a photoinitiator portion. The photoinitiator portion activates both free-radical and cationic curing mechanisms.

Cube-corner retroreflective articles having tailored divergence profiles

Abstract: Cube-corner retroreflective article having improved divergence profiles. The three lateral reflecting faces of the cube-corner retroreflective elements are formed by three intersecting sets of parallel V-shaped grooves, and at least one of the sets includes, in a repeating pattern, at least two groove side angles that differ from one another. Thereby the array of cube-corner retroreflective elements is divided into repeating sub-arrays that each comprise a plurality of cube-corner retroreflective elements in a plurality of distinctive shapes that retroreflect incident light in distinctively shaped light patterns.

Optical fiber distribution panel

Abstract: An improved fiber distribution panel including fiber connecting and splicing modules which are slidable into and out of a housing which is formed to support a plurality of said modules. Each module is provided with means for supporting a fiber connector at an angle with respect to the front edge thereof allowing access to the connectors and supports a booklet for storing slack fiber and for supporting permanent fiber connectors within said module.

Tissue gripping and cutting assembly for surgical instrument

Abstract: A surgical instrument including a reusable handle and a removable sheathed blade assembly comprising an elongate sheath with a plurality of elongate surgical blades longitudinally received within said sheath and selectively projectable therefrom along guided paths for exposure of the working heads of the blades. The working heads define, respectively, a cutting head and a gripping head. The sheathed assembly is introduced an operating site whereat the gripping head is exposed and engaged with tissue to be cut. The cutting head is subsequently moved into cutting engagement with the gripped tissue, after which both blades are retracted into the sheath and the sheathed blades removed from the operating site. The cutting blade is directly manually reciprocated with the gripping blade engaged with the cutting blade through a connection which allows for reciprocation of the gripping blade in response to reciprocal movement of the cutting blade, or, alternatively, reciprocation of the cutting blade independent of the gripping blade.

Fiber optic cable splice closure

Abstract: A fiber optic splice closure for protecting the splice made into a transmission cable, containing a plurality of fibers which are to remain unsevered, comprises a base to which the cable is anchored and in which slack fibers in the uncut cable are looped and stored free of transverse barriers. The seal is made with the cables and the base by a mating cover provided with a second area to receive splice trays and slack fibers selected from the cable for splicing.

Loop fastener portion with thermoplastic resin attaching and anchoring layer

Abstract: A loop fastener portion including a soft flexible sheet-like fibrous structure having a multiplicity of loops along a first surface adapted to be releasably engaged by a mating fastener portion, and a layer of thermoplastic resin adhered to a second major surface of the fibrous structure which anchors the loops in the fibrous structure and is softenable by the application of heat to adhere the fastener portion to a substrate such as the surface of a disposable diaper.

Pressure-sensitive tape construction incorporating resilient polymeric microspheres

Abstract: Tape products for diverse end users are obtained by applying to a sheet backing a layer of normally tacky and pressure-sensitive adhesive (PSA) containing and completely surrounding resilient non-tacky hollow thermoplastic polymeric microspheres. When the PSA is permanently bonded to the backing and the exposed surface has an irregular contour, a removable and repositionable product results. When the PSA forms a continuous matrix that is strippably bonded to the backing and is 1 mm or more thick, the resultant product is a foamlike transfer tape or foam tape. Depending on the product, the PSA can contain from about 1/5 to about 2/3% of the microspheres by volume.

Acrylate pressure-sensitive adhesives containing insolubles

Abstract: A bulk polymerization process for free radical polymerization of vinyl monomers in a wiped surface reactor is disclosed. Referring to FIG. 1; monomer streams 5 (after purification and silica gel column 2) and 7 are combined with free radical initiator 9 to form a premix 16. Pump 18 transfers the premix stream 22 through static mixer 24 into a wiped surface reactor 27. The reactor can be a counter rotating twin screw extruder which produces polymer stream 36 without the need of solvent and using residence times much shorter than prior art solution or emulsion processes. Some unique pressure sensitive adhesive acrylate polymers have been produced. They are believed to have a relatively high degree of branching. The bulk polymerization process permits the manufacture of pressure sensitive adhesive articles by extruding directly from the twin screw extruder onto a substrate.

Retroreflective sheet with enhanced brightness

Abstract: Retroreflective construction comprising a monolayer of microspheres with associated dielectric mirrors which are hemispherically surrounded by tangentially-oriented, preferably contour-conforming, reflective pigment nacreous flakes. The dielectric mirrors and reflective nacreous pigment flakes cooperate additively substantially without interfering with each other to provide a high brightness retroreflective sheet. The novel sheets retain much of their reflectivity after several launderings or drycleanings and, in some embodiments, can be made very flexible, making them well-suited for use as reflective fabrics.

Antimicrobial wound dressings

Abstract: Antimicrobial wound dressings are provided comprised of a substrate coated with an antimicrobially effective film of a silver salt. These antimicrobial wound dressings are prepared by vapor coating or sputter coating certain silver salts onto a variety of wound dressing substrates. Preferred silver salts are silver chloride and silver sulfate.

Article having surface layer of uniformly oriented, crystalline, organic microstructures

Abstract: Article comprising a substrate bearing a microlayer which comprises uniformly oriented, crystalline, solid, organic microstructures and a method for preparing said article. The microstructures may be mono- or polycrystalline. In the preferred embodiment, the microstructures are of uniform shape and size. The articles can be prepared by (1) depositing a vapor of an organic compound as a thin, continuous film onto a substrate to provide a composite, and (2) annealing the composite in a vacuum sufficiently such that a physical change is induced in the orginal deposited film to form the microstructures. The microlayer can be overcoated with other materials to provide desired properties to the article. The articles of this invention are useful for many forms of light trapping, energy absorption, imaging, data transmission and storage, and gradient index applications.

Electrically-conductive pressure-sensitive adhesive and biomedical electrodes

Abstract: An electrically-conductive, pressure-sensitive adhesive composition having a polymeric matrix comprised of copolymers of hydrogen bond donating monomer (for example acrylic acid) and hydrogen bond accepting monomers (for example N-vinylpyrrolidone) is disclosed. The polymeric matrix is homogeneously mixed with an electrically-­conductive plasticizing solution comprised of from 0% to 98% by weight water-soluble, polar organic compound (for example glycerol), 2% to 100% by weight water, and 0 to 12% by weight water-soluble salt. The composition contains from about 12% to 50% by weight non-volatile copolymer matrix and the hydrogen bond donating sites on the copolymer matrix are froma bout 5% to about 95% neutralized. Free radical polymerization methods of making the composition and biomedical electrodes incorporating the composition are also described.

Flexible bag with a pressure sensitive adhesive closure strip

Abstract: A flexible bag having front and back panels sealed along bottom and side edges. A pressure sensitive adhesive closure strip is adhered to the back panel and to the rear surface of the front panel. The front panel includes a transverse separation line intermediate the bottom edge of the bag and the closure strip. A portion of the front panel above the separation line may be removed from the bag so as to expose the closure strip for securing the back panel to the front surface of the front panel for closing the top of the bag.

High efficiency respirator

Abstract: The invention provides a filtration face mask which has an expanded filtration surface area and high filter efficiency. The mask includes at least two sidewall portions generally extending away from the face of the wearer and away from an annular base. A frontal portion bridges the sidewall portions and at least two supporting arche structures are disposed at the junction of the sidewall and frontal portions.

Method for priming hard tissue

Abstract: of the Disclosure A single phase aqueous solution containing water, a water-soluble film former (e.g., 2-hydroxyethylacrylate) and a salt of an acid (e.g, calcium trifluoroacetate) is used as a primer for adhering to or overcoating hard tissue such as tooth dentin.

Pavement markings containing transparent non-vitreous ceramic microspheres

Abstract: Pavement marking comprising ceramic microspheres held by a binder, said microspheres being solid, transparent, non-vitreous, ceramic particles which serve as lens elements in the retroreflective pavement markings. The ceramic microspheres formed by various sol gel techniques are characterized by having: A. at least one metal oxide phase; and B. an average minimum dimension of up to 125 micrometers. The inventive pavement markings retain reflectivity for a surprisingly long time.

Hearing aid ear piece having disposable, compressible polymeric foam sleeve

Abstract: Detachably secured to the ear piece of a hearing aid is a user-disposable sleeve comprising soft polymeric retarded recovery foam that can be compressed to be freely insertable into a person's ear canal and then allowed to recover to become wedged in the canal. The sleeve preferably includes a flexible, elongated plastic duct over which the foam fits, and the duct is formed with a screw thread of a rigid plastic which mates with a screw thread on the ear piece for easy attachment and removal. The external surface of the foam preferably is substantially cylindrical and can be formed with flutes to provide venting of the user's ear.

Apparatus and methods for delivering a predetermined amount of a pressurized fluid

Abstract: The present invention relates to metering valves and methods for repeatedly delivering a precise amount of a pressurized fluid such as an aerosol. Each metering valve is configured such that the metering chamber exists only upon actuation of the valve stem to dispense a dosage. Thus, the metering chamber is created, filled with aerosol formulation, and emptied during the brief moment that the valve stem is depressed and subsequently released by the user to dispense a dosage. Alternative embodiments of the present invention also include mechanisms for pressure filling an aerosol container through such a metering valve.

Microwebs and nonwoven materials containing microwebs

Abstract: Microfiber microwebs are provided. The microfiber microwebs have relatively dense nuclei with individual fibers and/or fiber bundles protruding therefrom. The microfiber microwebs can be incorporated into nonwoven webs of blown microfibers, air-laid staple fibers, or wood pulp fibers as well as into shaped articles having porous covering materials. The microfiber microwebs are useful in sorbent, filtration, and thermal insulation materials. The microfiber microwebs are prepared by divellicating a microfiber web to form discrete particles of microfiber microwebs.

Integrally molded card edge cable termination assembly, contact, machine and method

Abstract: A card edge connector (10) includes electrical contacts (15) for engaging traces of a printed circuit card to establish electrical connection therewith, a housing (16) for supporting the contacts, a strain relief (17) directly molded to at least part of the contacts and housing for securing the same as an integral structure, the contacts having a compliance characteristic in the card edge connector, and a secondary compliance mechanism (95) for increasing the effective compliance characteristic of the contacts in the card edge connector. Such secondary compliance mechanism is provided by a shrinkage of some of the molded strain relief material during cooling thereof. The contacts and housing provide part of a shut of function and a shut off key (56) inserted into the housing for use during the molding provides another part of a shut off function to block flow of molding material into a contacting area of the housing (27). The invention also relates to a method for making a card edge connector and a machine for making a card edge connector.

Unified pressure-sensitive adhesive tape

Abstract: A pressure-sensitive adhesive tape comprising a plurality of superimposed layers, at least one outer layer being a pressure-sensitive adhesive layer, contiguous layers defining an interface therebetween, each of said layers comprising a photopolymerized matrix of polymeric chains; said polymeric chains extending from the matrix of one of said layers through said interface into the matrix of a contiguous layer; said polymeric chains comprising polymerized monomers having migrated from the matrix of each contiguous layer prior to polymerization, whereby said layers cannot be delaminated.

Microwave food package and grease absorbent pad therefor

Abstract: A package of food containing a substantial amount of water and solidified grease that can be cooked within the package in a microwave oven. A pad adjacent the food comprises microwave radiation transparent generally hydrophobic liquid grease absorbing materials that are capable of holding the amount of grease in the food when it is melted; and a vapor tight microwave radiation transparent enclosure surrounding the pad and food includes means for venting steam from the enclosure as the food is cooked. Preferably, the pad is produced from microfibers constructed of a composition comprising a blend containing substantially equal parts by weight of polypropylene and poly 4-methylpentene-1.

Cutting element with wear resistant crown

Abstract: A cutting element adapted to be used in a rotary drill bit is made by positioning in an appropriately shaped die cavity a quantity of a mixture of tungsten carbide and 4 to 11 percent cobalt in the shape of a crown for defining an outer surface for the tip portion of the cutting element using a pressure of less than about 600 pounds per square inch; positioning in the cavity a quantity of a mixture of tungsten carbide and 12 to 17 percent cobalt sufficient to form almost all of a base portion and at least an inner part of the tip portion for the cutting element; pressing the two quantities of the mixtures together and into the die at pressures in the range of about 10 to 15 tons per square inch; and sintering the pressed insert to form the cutting element.

Sensor with overcoating and process for making same

Abstract: A sensor comprising a sensing element capable of sensing a component in an aqueous medium and an overcoating at least partially covering the sensing element. The overcoating comprises a water insoluble, component permeable, cross-linked cellulosic material and an effective amount of an opaque agent.

Apparatus and method for patterning a film

Abstract: The present invention relates to an apparatus and method for patterning areas of a radiation absorbent film material. In the preferred embodiment, the film material is at least partially electrically conductive. The radiation is focused onto the film by a lenticular lens having a plurality of optically active elements to provide a radiation pattern on the film and remove or displace portions of the film to form a corresponding pattern, preferably a conductive pattern. The film may have one or more layers or regions, but at least one region must be radiation absorbent in order to allow the formation of patterns in the film in accordance with the present invention. The areas of the film affected by the phenomenon of radiation absorption are non-conductive voids which may separate the film into a plurality of conductive grid lines whereby the film is useful with a conductive lens film to increase the apparent efficiency of a photovoltaic cell.

Method for fabricating an interconnected array of semiconductor devices

Abstract: Semiconductor layer and conductive layer formed on a flexible substrate, divided into individual devices and interconnected with one another in series by interconnection layers and penetrating terminals.