3832 results about "Contact angle" patented technology

The present invention relates to a soft contact lens, and provides a contact lens which shows small and stable contact angle to water at its surface in water as well as in air, little deposition in wearing, high oxygen permeability, no adhesion of lens to a cornea and superior extended-wearing characteristics. The present invention provides a hydrogel soft contact lens which has contact angle at a lens surface in a range of 10-50° by the captive bubble method in water and 30-90° by the sessile drop method in air, oxygen permeability of not less than 30 and water content of not less than 5%, and also a hydrogel soft contact lens consisting of a polymer comprising a hydrophilic siloxanyl monomer shown by a specified general formula.

The present invention provides an improved LbL-coating process for modifying the surface of a medical device, preferably an ophthalmic device, more preferably a contact lens. An LbL coating on a contact lens, which is prepared according to the process of the invention, can have increased hydrophilicity characterized by an averaged contact angle of about 80 degree or less, preferably about 50 degrees or less, while maintaining the desired bulk properties such as oxygen permeability and ion permeability of lens material.

The invention is related to methods and apparatus that manipulate droplets in a microfluidic environment. Advantageously, embodiments of the invention manipulate droplets by controlling the electro-wetting characteristics of a surface with light, thereby inducing a gradient in the surface tension of a droplet. The gradient in the surface tension propels the droplet by capillary force. A variety of operations, such as transporting, joining, cutting, and creating can be performed. Advantageously, embodiments of the invention obviate the need to create a relatively large and complex control electrode array. A plurality of photoconductive cells or a layer of a photoconductive material selectively couples an electrode carrying an electrical bias to otherwise floating conductive cells in response to a beam of light. The electrical bias applied to the conductive cell generates a localized electric field, which can change the contact angle of the droplet, thereby permitting the droplet to be propelled.

An article having low wettability is presented. The article comprises a body portion and a surface portion disposed on the body portion. The surface portion comprises a plurality of features disposed on the body portion, and the features have a size, shape, and orientation selected such that the surface portion has a wettability sufficient to generate, with a reference liquid, a contact angle of at least about 100 degrees. The features comprise a height dimension (h) and a width dimension (a), and are disposed in a spaced-apart relationship characterized by a spacing dimension (b). The ratio of b/a and the ratio of h/a are such that the drop exhibits metastable non-Wenzel behavior.

The instant invention provides a method for improving the miscibility of the lower molecular weight unsaturated siloxane-polyether copolymers with the alpha , omega -divinylpolysiloxanes without loss of storage stability, or delay of cure at the vulcanization temperature, or loss of permanent hydrophilicity or other desirable features of the cured polysiloxane. The compositions of the present invention comprise one or more alpha , omega -divinylpolysiloxanes, unsaturated polysiloxane-polyether copolymers having from 2 to 5 silicon atoms per molecule which are preferably trisiloxanes, and a compatibilizing additive. The permanently hydrophilic, rapidly wettable polysiloxane compositions yield static water contact angles <50 DEG dynamic advancing contact angles of less than about 100.

The invention is directed to nanostructure surface treatments, coatings or modifications formed from nanoscale building blocks. The nanostructure surface treatments, modifications or coatings have hydrophobic, hydrophilic and surface adherence properties. The nanoscale building blocks have orientation, geometry, packing density and composition that may be adjusted to control the unique surface characteristics of the desired treatment, coating or modification. Applications of this nanostructure technology include surgical clips, staples, retractors, sutures and manipulators where an improvement in traction, retention or occlusion is desired without excessive material or tissue deformation or where high compressive forces would be undesirable, dangerous or ineffective. In one aspect, a nanostructure surface treatment for a medical device having an external surface is disclosed, wherein the treatment is applied on the external surface to provide a hydrophobic or a hydrophilic surface. With this aspect, the treatment comprises titanium dioxide and provides nanoscopic structures having nearly vertical sidewalls. The treated surface of the device has contact angles greater than or equal to 150 degrees. The vertical sidewalls provide a negative capillary effect and have a width of about 200 nm. The vertical sidewalls attach to a wet surface by the negative capillary effect. The van der Waals forces of the vertical sidewalls enable the treated surface to attach to a dry surface. The treatment may be vapor deposited and cured on the device, or the treatment may be laser blasted on the device.

An article comprising a surface portion is provided. The surface portion has a plurality of primary features, and the primary features have a height dimension in the range from about I micron to about 500 microns, an aspect ratio in the range from about 0.5 to about 10, and a spacing dimension in the range from about 0.5 to about 50 feature width units. The surface portion comprising the features has a wettability of the surface sufficient to generate, with a reference fluid, a static contact angle of greater than about 120 degrees and a total transmission of at least about 70% in the visible range of electromagnetic radiation.

To a resist composition, an alkali-soluble polymer having fluorinated ester-containing lactone units incorporated therein is included as an additive. The resist composition forms a resist film having a reduced contact angle after development. The resist film prevents water penetration during immersion lithography.

The invention relates to an underwater super-oleophobic oil-water separation mesh membrane as well as a preparation method and application thereof. A 100-140-mesh fabric mesh is used as the substrate of the oil-water separation mesh membrane; and a hydrogel cladding layer is formed by the crosslinking polymerization of polymer monomers on the mesh wires of the fabric mesh by a photo-initiated polymerization method, thus obtaining the mesh membrane provided by the invention. The oil-water separation mesh membrane is super-hydrophilic in air and underwater and super-oleophobic underwater; the contact angle with oil drops underwater is greater than 150 degrees; and the adhesion to oil drops is low. The mesh membrane provided by the invention can be applied to oil-containing sewage treatment, chemical separation, environmental protection and the like. For oil-water separation, the mesh membrane has the advantages of good separation effect, fast separation, low cost, low energy consumption, convenience, no other chemical additive and the like, and is easy to recover for multiple recycling, and suitable for wide-range preparation.

Provided are a magnetic recording medium, in which a magnetic layer includes a ferromagnetic hexagonal ferrite powder, a binding agent, and an oxide abrasive, an intensity ratio Int(110)/Int(114) obtained by an X-ray diffraction analysis of the magnetic layer by using an In-Plane method is 0.5 to 4.0, a vertical squareness ratio of the magnetic recording medium is 0.65 to 1.00, a contact angle with respect to 1-bromonaphthalene measured regarding a surface of the magnetic layer is 50.0° to 55.0°, and an average particle diameter of the oxide abrasive obtained from a secondary ion image obtained by irradiating the surface of the magnetic layer with a focused ion beam is 0.04 μm to 0.08 μm, and a magnetic recording and reproducing device including this magnetic recording medium.

This invention is directed to super-absorbent material, which comprises a super absorbent polymer core that is coated with an organic, polar coating agent, and whereby the particulate super-absorbent material has a contact angle and a corresponding cos CA_m (as defined herein), whereby the cos CA_m is more than 0.3, and whereby, when said coating agent is in the form of particles, said coating agent particles have a (weight) mean particle size of from 0.001 to 1 micron. The material is useful for absorbent structures and absorbent articles (comprising such structures). The coated super-absorbent material is typically present in said absorbent structure at least at a concentration of 50% by weight of the structure, preferably even 80% or even 90%. The invention also provides a process for making the absorbent material.

There is disclosed a resist composition comprising, at least, a polymer including repeating units represented by the following general formula (1). There can-be provided a resist composition that has a good barrier property against water, prevents resist components from leaching to water, has high receding contact angle against water, does not require a protective film, has an excellent process applicability, suitable for the liquid immersion lithography and makes it possible to form micropatterns with high precision.

The magnetic tape includes a non-magnetic support; a magnetic layer including ferromagnetic powder and a binding agent on one surface side of the non-magnetic support; and a back coating layer including non-magnetic powder and a binding agent on the other surface side of the non-magnetic support, in which a thickness of the back coating layer is equal to or smaller than 0.30 μm, a logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the back coating layer is equal to or smaller than 0.060, and a contact angle with respect to 1-bromonaphthalene measured regarding a surface of the back coating layer is 15.0° to 30.0°.

The present invention provides a method of producing pristine or non-oxidized nano graphene platelets (NGPs) that are highly conductive. The method comprises: (a) providing a pristine graphitic material comprising at least a graphite crystallite having at least a graphene plane and an edge surface; (b) dispersing multiple particles of the pristine graphitic material in a liquid medium containing therein no surfactant to produce a suspension, wherein the multiple particles in the liquid have a concentration greater than 0.1 mg/mL and the liquid medium is characterized by having a surface tension that enables wetting of the liquid on a graphene plane exhibiting a contact angle less than 90 degrees; and (c) exposing the suspension to direct ultrasonication at a sufficient energy or intensity level for a sufficient length of time to produce the NGPs. Pristine NGPs can be used as a conductive additive in transparent electrodes for solar cells or flat panel displays (e.g., to replace expensive indium-tin oxide), battery and supercapacitor electrodes, and nanocomposites for electromagnetic wave interference (EMI) shielding, static charge dissipation, and fuel cell bipolar plate applications.

An absorbent paper sheet is treated with an aqueous wax dispersion such that the sheet includes a fused wax and emulsifier residue in an amount of from about 1 to about 20 weight percent of the sheet based on the combined weight of the fiber, wax residue and an emulsifier residue in the sheet. The fused wax emulsion operates to make at least one surface of the sheet laterally hydrophobic, exhibiting a moisture penetration delay of at least about 2 seconds and less than about 40 seconds as well as a typical contact angle with water at one minute of at least about 50 degrees. There is thus provided absorbent products which exhibit both absorbency and resistance to moisture penetration. The treated sheet further exhibits microbial barrier properties, impeding transfer of bacteria, for example, through the sheet. There are produced tissue products which resist moisture penetration from propelled liquids as well as sequester sorbed liquids in the interior of the tissue.

The magnetic tape has a magnetic layer containing ferromagnetic powder and binder on one surface of a nonmagnetic support and has a backcoat layer containing nonmagnetic powder and binder on the other surface thereof, wherein the thickness of the backcoat layer is less than or equal to 0.20 μm, and the contact angle for 1-bromonaphthalene that is measured on the surface of the backcoat layer falls within a range of 10.0° to 30.0°.