Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
  • C08B5/00—Preparation of cellulose esters of inorganic acids, e.g. phosphates
  • C08B5/02—Cellulose nitrate, i.e. nitrocellulose
  • C08B5/04—Post-esterification treatments, e.g. densification of powders, including purification
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J3/00—Processes of treating or compounding macromolecular substances
  • C08J3/12—Powdering or granulating
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
  • C09D101/00—Coating compositions based on cellulose, modified cellulose, or cellulose derivatives
  • C09D101/08—Cellulose derivatives
  • C09D101/16—Esters of inorganic acids
  • C09D101/18—Cellulose nitrate
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2301/00—Characterised by the use of cellulose, modified cellulose or cellulose derivatives
  • C08J2301/08—Cellulose derivatives
  • C08J2301/16—Esters of inorganic acids
  • C08J2301/18—Cellulose nitrate

Definitions

• the present invention relates to a process for the production of compressed, free-flowing, water- or alcohol-moist nitrocellulose by pushing it through a perforated plate.
• Low-esterification nitrocelluloses with a nitrogen content of up to 12.6% which are mainly used in the coatings industry, are produced by esterification of celluloses with nitrating acids, which usually consist of a mixture of nitric acid, sulfuric acid and water.
• the nitrocellulose obtained in this way which has a fibrous structure, must be phlegmatized to avoid spontaneous combustion. Different desensitizing agents are used for this.
• nitrocelluloses are usually mixed with the moisture content of the alcohols (such as ethanol,
• the fibrous nitrocelluloses Due to their wool-like structure, the fibrous nitrocelluloses have bulk densities of between 250 and 350 g / l on average.
• the low bulk density has an unfavorable effect on packaging and shipping costs for the dispatch of such products. This is countered by pounding the fibrous nitrocellulose in the packaging, such as a drum or a cardboard box becomes. In this way, the bulk density is increased, but at the same time the flowability of the nitrocellulose is impaired. This leads to an increased workload when emptying the nitrocellulose container.
• a compressing force P 2M + 6400 is exerted on the moist, fibrous nitrocellulose, where P is the force in pounds per square inch and M is the mean fiber length of the nitrocellulose in microns.
• the force preferably between 15,000 and 17,000 psi (1,110-1,196 Kp / cm 2 ), is applied by two counter-rotating rollers working without a gap.
• the object of the present invention was therefore to provide a new process for the production of compressed free-flowing nitrocellulose which avoids the dehumidification of the nitrocellulose.
• compressed nitrocellulose can also be obtained in that the rotating mills in a pan mill (Wheels), which run on a perforated die (plate), press the moistened nitrocellulose through the holes (eg holes) of the die (see Fig. 1). The nitrocellulose coating raw material is thereby compacted. Below the die is a shear-off device with which the granulate-like moldings are brought to the desired length. The cross-sectional shape of the moldings is determined by the shape of the hole cross section.
• the resulting compacted material can be hard (with sharp edges) to soft (easily crushable with your fingers).
• the pressing ratio P is responsible for the consistency of the compressed nitrocellulose.
• P is defined as the ratio of the length of the hole to the diameter of the hole in the die:
• the press ratio P should be between 0.5 and 5.0, preferably between 0.5 and 3.0. It is also possible for the holes in the die to have a square, rectangular, oval or irregularly shaped cross section. The number of holes per unit area of the die depends on the stability of the die. Due to the compression, it is possible to increase the bulk density of the nitrocellulose used many times over and thus to obtain a free-flowing (free-flowing) material.
• the uncompressed material is fed into the pan mill via a dosing device (e.g. screw, belt). It is also possible to inertize the pan mill, e.g. with nitrogen or carbon dioxide.
• a dosing device e.g. screw, belt
• inertize the pan mill e.g. with nitrogen or carbon dioxide.
• the following examples are intended to describe the process, but not to limit it.
• the distance between the shearing device and the underside of the die was 20 mm.
• the compressed goods have a moisture content of 34.2% and a bulk density of 578 g / 1.
• the moldings remained free-flowing even after eight weeks of storage in a 110-1 drum.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Polymers & Plastics (AREA)
• Medicinal Chemistry (AREA)
• Health & Medical Sciences (AREA)
• Materials Engineering (AREA)
• Engineering & Computer Science (AREA)
• Life Sciences & Earth Sciences (AREA)
• Biochemistry (AREA)
• Wood Science & Technology (AREA)
• Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
• Polysaccharides And Polysaccharide Derivatives (AREA)
• Processes Of Treating Macromolecular Substances (AREA)
• Paints Or Removers (AREA)
• Chemical And Physical Treatments For Wood And The Like (AREA)
• Application Of Or Painting With Fluid Materials (AREA)
• Glass Compositions (AREA)
• Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)
• Casting Or Compression Moulding Of Plastics Or The Like (AREA)
• Processing Of Solid Wastes (AREA)
• Crushing And Grinding (AREA)
• Paper (AREA)
• Coating Apparatus (AREA)
• Cosmetics (AREA)
• Medicinal Preparation (AREA)
• Holo Graphy (AREA)

Priority Applications (10)

Applications Claiming Priority (2)

Publications (1)

Family

ID=7899519

Family Applications (1)

Country Status (15)

Cited By (1)

Families Citing this family (5)

Citations (4)

Family Cites Families (12)

• 1999
  • 1999-03-03 DE DE19909230A patent/DE19909230A1/de not_active Withdrawn
• 2000
  • 2000-02-23 BR BRPI0008706-8A patent/BR0008706B1/pt not_active IP Right Cessation
  • 2000-02-23 KR KR1020017011151A patent/KR100637815B1/ko not_active Expired - Lifetime
  • 2000-02-23 AU AU38061/00A patent/AU3806100A/en not_active Abandoned
  • 2000-02-23 CN CNB008044627A patent/CN1146577C/zh not_active Expired - Lifetime
  • 2000-02-23 US US09/914,436 patent/US6896752B1/en not_active Expired - Fee Related
  • 2000-02-23 HK HK02106778.3A patent/HK1045317B/zh not_active IP Right Cessation
  • 2000-02-23 HU HU0105483A patent/HU225789B1/hu not_active IP Right Cessation
  • 2000-02-23 WO PCT/EP2000/001481 patent/WO2000052058A1/de not_active Ceased
  • 2000-02-23 AT AT00916861T patent/ATE248193T1/de not_active IP Right Cessation
  • 2000-02-23 JP JP2000602281A patent/JP4666768B2/ja not_active Expired - Fee Related
  • 2000-02-23 DE DE50003455T patent/DE50003455D1/de not_active Expired - Lifetime
  • 2000-02-23 YU YU63101A patent/YU49435B/sh unknown
  • 2000-02-23 EP EP00916861A patent/EP1183276B3/de not_active Expired - Lifetime
  • 2000-02-23 CZ CZ20013137A patent/CZ300327B6/cs not_active IP Right Cessation
  • 2000-03-01 TW TW089103531A patent/TWI271408B/zh not_active IP Right Cessation

Patent Citations (4)

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