A dip-molded article includes an external molded layer and internal molded layer. The external molded layer includes a content of an ethylenically unsaturated nitrile-based monomer-derived repeating unit is 35 wt % to 60 wt %, and the internal molded layer in which a content of an ethylenically unsaturated nitrile-based monomer-derived repeating unit is 10 wt % to 28 wt %.

A copolymer latex of a copolymer comprising 50 to 88 wt % of a conjugated diene monomer unit, 10 to 40 wt % of an ethylenically unsaturated nitrile monomer unit, and 2 to 10 wt % of an ethylenically unsaturated acid monomer unit, the copolymer latex having an insoluble content in methyl ethyl ketone of 70 wt % or less and a swelling degree in methyl ethyl ketone of 40 times or more when the copolymer is formed into a dry film.

A method for producing a polymer latex, including an emulsification step of mixing a polymer solution obtained by dissolution of synthetic polyisoprene and/or a styrene-isoprene-styrene block copolymer in an organic solvent, with an aqueous solution including 0.1 to 30 parts by weight of a rosinate based on 100 parts by weight in total of the synthetic polyisoprene and the styrene-isoprene-styrene block copolymer, and emulsifying the resultant in water to thereby obtain an emulsified liquid, a solvent removal step of removing the organic solvent in the emulsified liquid, and a concentration step of concentrating the emulsified liquid from which the organic solvent is removed, and also adjusting the content rate of the rosinate in the emulsified liquid after concentration, in the range of 0.1 to 3 parts by weight based on 100 parts by weight in total of the synthetic polyisoprene and the styrene-isoprene-styrene block copolymer in the emulsified liquid.

An apparatus and a method are provided for a latex-based packaging material configured to provide a dust-free alternative to vermiculite packaging materials. The latex-based packaging material comprises a portion of a latex-based waste formulated into a recycled latex emulsion, and a portion of particulate material into which the recycled latex emulsion is mixed so as to form a latex-based pulp. In some embodiments, additional components, such as any of various plasticizers, coloring agents, or hardeners, may be included in the latex-base pulp. The latex-based pulp is dispensed and dried so as to form the latex-based packaging material in a variety of desired shapes. Drying may be accomplished by way of unaided atmospheric evaporation, or by way of various conventional drying methods. In some embodiments, the desired shape of the packaging material comprises latex-based packaging peanuts suitable for separating and cushioning forces between containers during transportation in a larger container.

A polymer latex, including a polymerization step of polymerizing a monomer in organic solvent to thereby obtain polymer solution of synthetic polyisoprene and/or styrene-isoprene-styrene block copolymer, antioxidant addition step of adding antioxidant to the polymer solution of synthetic polyisoprene and/or styrene-isoprene-styrene block copolymer at proportion of 0.01-1.00 parts by weight per 100 parts by weight of the synthetic polyisoprene and/or styrene-isoprene-styrene block copolymer, and emulsification step of emulsifying the polymer solution which the antioxidant is added, in water in the presence of a surfactant, to thereby obtain polymer latex, wherein the emulsification performs in the emulsification step so the ratio D75/D25 of the volume particle size D75 at a cumulative frequency of 75% to the volume particle size D25 at a cumulative frequency of 25% of a particle of the synthetic polyisoprene and/or styrene-isoprene-styrene block copolymer included in the polymer latex is 1.90 or more and 2.30 or less.

A female die for manufacturing a wall thickness-variable glove and a glove manufactured using the female die. The female die for a wall thickness-variable glove comprises a base (1), an arm portion (2), a palm portion (3), and finger portions. The base (1), the arm portion (2), the palm portion (3) and the finger portions are connected in sequence. The palm portion (3) comprises a palm center member (4) and a palm back member (5) connected to the palm center member (4). The die can be adopted for effectively thickening a hand back portion of the manufactured glove, and therefore the flexibility of other portions of the glove is guaranteed on the premise of effectively protecting the hand back of a doctor, the requirement for protection of the hand back of the doctor under an environment such as an interventional operation is met, and the characteristics of protection and use flexibility are both achieved.

According to this procedure, these steps are made:

a) immersing a shaped mold (4) in a dipping process in a liquid synthetic polyisoprene (IR) (synthetic latex), wherein the shaped mold (4) has previously been treated with coagulation agent (coagulants) or thermally treated,

b) after the immersion, the synthetic polyisoprene layer is left on the shaped mold (4) and is freed from all salts with water,

c) thereafter, the synthetic polyisoprene layer together with the shaped mold (4) is vulcanized in an oven,

d) the synthetic polyisoprene layer is removed from the mold (4),

e) the salts precipitated by the vulcanization on the synthetic polyisoprene molded body (11) are washed off with water and a chlorine-containing solution,

f) the synthetic polyisoprene molded body (11) is halogenated to neutralize its pH and to increase its suppleness in contact with body skin with a halogenating solution,

g) the synthetic polyisoprene molded body (11) is dried. The electro-protective gloves thus produced are much more comfortable to wear, provide better insulation, even with thinner wall thickness, and they are more durable.

One method for creating barrier products (for example, condoms and gloves) includes: (a) dipping a former into a tank of elastic compound. The former has an indentation extending inwardly from an outer surface for creating a first protrusion on a first face of the barrier product. The method further includes: (b) removing the former from the tank of elastic compound, whereby some of the elastic compound removably adheres to the former and fills the indentation; (c) applying supplemental material to the elastic compound, whereby creating a second protrusion on a second face of the barrier product; and (d) fully drying the supplemental material. One barrier product includes an elastic wall having opposed faces, and first and second protrusions respectively extend from the opposed faces. The first and second protrusions are in cross-sectional alignment whereby rotational input forces on the first protrusion create rotational output forces on the second protrusion.

Pore-free rubber articles are prepared by dip-molding in a dipping medium that includes a vulcanizing agent, then partially-cured by immersing the dip former in a heated liquid bath that is chemically inert. A particularly effective liquid bath is a molten, nitrite free inorganic salt. The partially-cured rubber is then maintained at a desired curing temperature in a low/no oxygen heating oven to complete curing. Alternatively, upon removal from the molten salt bath, the latex film is quenched.

A leather substrate formed from waste leather and its method of production, particularly a leather substrate made up substantially of a collagen fibril matrix.