Abstract: A process for saline-solution soluble xanthan gum which comprises the steps of precipitating xanthan gum by mixing, with stirring, an aqueous solution of xanthan gum with an organic solvent which is a non-solvent to xanthan gum but is hydrophilic, removing liquid from the precipitated xanthan gum to a liquid content of at most 50%, disintegrating the cake of xanthan gum after the liquid removal to an average grain size of from 0.3 to 2 cm in diameter, and drying the disintegrated xanthan gum by fluidizing the same at a temperature not exceeding 80.degree. C.

Abstract: Novel bisphenol carboxylic acid tertiary ester derivatives having two aromatic ether groups and an ester group which are all replaced by acid labile groups are provided. The derivatives are used as a dissolution inhibitor in a chemically amplified positive resist composition comprising an organic solvent, an alkali soluble resin, and a photo-acid generator. Since the dissolution inhibitor has a highly reactive acetal group as an acid labile group, its coupling-off rapidly takes place after exposure. The dissolution inhibitor itself is less alkali soluble and its acid decomposition product is a phenol derivative having a carboxylic acid group with high alkali solubility, leading to a high dissolution contrast.

Abstract: In a chemically amplified positive resist composition comprising an organic solvent, an acid labile group-protected resin and a photoacid generator, a compound having a weight average molecular weight of 100-1,000 and at least two phenolic hydroxyl groups in a molecule wherein the hydrogen atom of the phenolic hydroxyl group is partially replaced by an acid labile group in an overall average proportion of 10-80% is blended as a dissolution controller. The resist composition is highly sensitive to actinic radiation, has improved sensitivity and resolution, and is suitable for use in a fine patterning technique and commercially acceptable.

Abstract: The invention provides a novel sulfonium salt having a substituted or unsubstituted arylsulfonate anion. The novel sulfonium salt minimizes the influence of deactivation by basic compounds not only at a resist surface, but also at a resist-substrate interface, assists a resist to be configured to a definite pattern profile. When the sulfonium salt has an acid labile group, it is effective for increasing the dissolution contrast between exposed and unexposed areas. The sulfonium salt is useful in a chemically amplified positive resist composition which lends itself to fine patterning and features high resolution.

Abstract: The invention provides a novel sulfonium salt having at least one acid labile group attached to a phenyl group in a molecule and a C.sub.2 -C.sub.20 alkylsulfonate or arylsulfonate anion whose alkyl or aryl has as a substituent an electron withdrawing group such as fluorine and nitro group. The novel sulfonium salt is effective for increasing the dissolution contrast between exposed and unexposed areas. Upon exposure, it generates a substituted alkyl or arylsulfonic acid which is a weak acid, minimizing the influence of side reaction and deactivation during PEB step. The sulfonium salt is useful in a chemically amplified positive resist composition which lends itself to fine patterning and features high resolution.

Abstract: A water-soluble coating composition for forming a layer to be placed on the upper surface of a resist is provided without use of Freons. The material includes an aqueous solution containing a) at least one water-soluble polymer selected from the group consisting of poly(N-vinylpyrrolidone) homopolymers and water-soluble copolymers of N-vinylpyrrolidone and other vinyl monomers, b) at least one fluorine-containing organic acid, and c) at least one amino acid derivative. The film formed through use of the material of the invention serves as both an anti-reflective film and a protective film. The material of the present invention provides a number of advantages in the formation of resist patterns, including excellent film-forming properties, excellent dimensional accuracy and aligning accuracy, simple and easy handling, high productivity, and good reproducibility.

Abstract: In a chemical amplification positive resist composition comprising an organic solvent, a resin and a photoacid generator, at least two polymers having different molecular weights selected from polyhydroxystyrenes having some hydroxyl groups protected with acid labile groups are used. Among the polymers, a high molecular weight polymer has a molecular weight dispersity (Mw1/Mn1) of up to 1.5, and a low molecular weight polymer has a dispersity (Mw2/Mn2) of up to 5.0. The weight average molecular weight ratio Mw1/Mw2 is between 1.5/1 and 10.0/1. The resist composition is highly sensitive to actinic radiation, has improved sensitivity and resolution, and is suitable for use in a fine patterning technique and commercially acceptable.

Abstract: Pullulan is precipitated from an aqueous solution by mixing with a hydrophilic organic solvent incapable of dissolving pullulan. Solid pullulan is then separated from the liquid component of the dispersion by feeding the dispersion into a V-type disk press having a pair of discoid screens arranged so that the distance between them decreases as they are rotated. The pullulan dispersion is pressed by the discoid screens, recovering the liquid component through the screens. The resulting low-liquid-content pullulan continues to rotate together with the screens to an outlet, where it is discharged from the press.

Abstract: The process comprises heat-treating a xanthan gum fermented broth, and consecutively treating the broth first with alkaline protease and then with lysozyme or in reverse order, and thereafter recovering xanthan gum from the treated broth. A clear aqueous solution of xanthan gum may be obtained without complex procedures.

Abstract: A xanthan gum having an improved transmittance is disclosed. Further, the transmittance of the xanthan gum is at least 75% in an 1% by weight aqueous solution. The xanthan gum is prepared by subjecting a strain ATCC 55429 or ATCC 55298 to submerged fermentation conditions to produce a broth containing the gum and debris. The broth is then subjected to heating at a temperature from 45.degree. to 70 .degree. C. for a period of time of at least one half to two hours and at a pH of 9 to 12.5. Two enzyme treatments are performed using an alkaline protease and lysozyme of which the order of their application is irrelevant to the recovery of the xanthan gum. The enzymes are applied at specific temperatures and time periods as well as pH conditions such as a protease is applied at a temperature of 40.degree. to 65 .degree. C. for a period of from 20 minutes to five hours at a pH range of 6 to 10; and the lysozyme is applied at a temperature of 25.degree. to 60 .degree. C.

Abstract: A xanthan gum-containing fermented solution is subjected to an enzyme treatment for solubilizing the microbial cells present in the fermented solution. While the fermented solution having undergone the enzyme treatment is maintained at a temperature of 50.degree. C. to 80.degree. C., and xanthan gum is precipitated by adding an hydrophilic organic solvent incapable of dissolving xanthan gum to the fermented solution. When a rotary turbine is used, the precipitate can be cut with a shearing cutter to recover a finely-divided fibrous product.

Abstract: A method for continuously precipitating a polysaccharide dissolved in an aqueous solution wherein a non-solvent for the polysaccharide is admixed with the aqueous solution to cause the polysaccharide to precipitate from the solution. The method includes the step of simultaneously feeding the aqueous solution containing the dissolved polysaccharide and the non-solvent through respective constant flow rate-pumps to produce non-pulsating metered first and second streams which are unaffected by pressure changes in the aqueous solution or the non-solvent fed to the respective pumps. The metered streams are simultaneously introduced from the respective pumps into a rotary turbine to mix the solution and the non-solvent and precipitate the polysaccharide. The precipitated polysaccharide is cut with an interlocking cutter which comprises a fixed cutter and a rotary cutter, and a suspension of finely cut polysaccharide particles is continuously withdrawn.

Abstract: The process includes heat-treating a xanthan gum fermented broth, and consecutively treating the broth first with alkaline protease and then with lysozyme or in reverse order, and thereafter recovering xanthan gum from the treated broth. A clear aqueous solution of xanthan gum may be obtained Without complex procedures.

Abstract: Disclosed is a novel organosilicon-containing derivative of pullulan of which an organopolysiloxane moiety having a silethylene linkage is bonded to the glucose residue of pullulan through a urethane linkage. Different from conventional organopolysiloxane-modified pullulans, the inventive derivative is stable against attack of water and exhibits unique properties as a combination of the properties inherent in pullulan and in silicones. The organosilicon-containing pullulan of the invention can be easily prepared under mild reaction conditions by reacting an isocyanato group-containing organopolysiloxane with the glucosic hydroxy groups of pullulan.

Abstract: A method for the fermentation production of xanthan gum which comprises the step of carrying out culture by using a water-soluble inorganic nitrogen component alone as the nitrogen source of a production medium, and by mixing and using the water-soluble inorganic nitrogen component and a water-insoluble organic nitrogen component as the nitrogen sources of a seed fermentation medium.

Abstract: A method for reducing the number of contaminative live bacteria in xanthan gum which comprises the step of washing a mixture of 100 parts by weight of water-containing isopropanol having an isopropanol concentration of 50 to 100% by weight and 1 to 100 parts by weight of the xanthan gum under heating conditions.

Abstract: A modified xanthan gum has a viscosity of not less than 800 cP as determined on a 0.5% by weight solution thereof in a 12% by weight aqueous sodium chloride solution at 20.degree. C. and a ratio of this viscosity to that determined on a 0.5% by weight solution thereof in distilled water of not less than 1.5. The modified xanthan gum can be prepared by a method comprising the steps of mixing an organic solvent which does not dissolve xanthan gum and is hydrophilic with an aqueous solution of xanthan gum in a mixer, cutting, into fine fibrous materials, deposites formed in the mixed solution together with the mixed solution with a cutter, separating and recovering the suspended fine fibrous materials from the mixed solution and then drying the materials at a temperature of not more than 80.degree. C. The modified xanthan gum can directly be dissolved in aqueous solutions of salts such as common salt even at room temperature and can thus easily show a desired effect of thickening the aqueous salt solutions.

Abstract: A method for producing streptovaricin by culturing a streptovaricin producing strain in the presence of a nonionic adsorbent. This procedure substantially increases the production efficiency of the streptovaricin. A second embodiment wherein the streptovaricin producing strain is produced in the presence of fumaric acid or its water soluble salts to provide improvements in production efficiency is also disclosed.

Abstract: A method for producing streptovaricin by culturing a streptovaricin producing strain in the presence of a nonionic adsorbent. This procedure substantially increases the production efficiency of the streptovaricin. A second embodiment wherein the streptovaricin producing strain is produced in the presence of fumaric acid or its water soluble salts to provide improvements in production efficiency is also disclosed.

Abstract: A bag-like dispenser is proposed which contains a sex pheromone compound of insects and is used for sustainedly releasing the pheromone compound at a uniform emission rate over a long period of time so as to exhibit effectiveness for the population control of pests by distributing a number of the dispensers over fields. The bag-like dispenser body is formed of a specific polymeric laminate film having a thickness of 20-200 .mu.m and composed of at least two layers or, preferably, of three layers, in which one of the layers is a film of a polymer or copolymer of vinylidene chloride having a thickness of 4-20 .mu.m as the intermediate layer of the three-layered laminate and the other layer or each of the other layers is a film of a specific polymer having a specified thickness, such as a film of a polyolefin, copolymer of ethylene and vinyl acetate, poly(vinyl chloride), copolymer of vinyl chloride and vinyl acetate and the like.