Analysis of the most popular patent technology of

Polylactic acid (PLA) is a new type of polyester material produced with organic lactic acid as raw material. PLA has good biodegradability, can be completely degraded by microorganisms in nature after use, and does not pollute the environment. It has the advantages over existing plastic polyethylene, polypropylene, polystyrene and other materials, and is defined by the industry as the most promising new packaging material in the new century, It is a star of environmental protection packaging materials, and is expected to replace polyethylene, polypropylene, polystyrene and other materials in plastic products in the future, with broad application prospects

polylactic acid has good mechanical and physical properties. It is suitable for blow molding, thermoplastic and other processing methods. It is convenient to process and widely used. It can be used to process all kinds of plastic products, packaged food, fast food lunch boxes, non-woven fabrics, industrial and civil fabrics from industry to civil use, and can also be processed into agricultural fabrics, health care fabrics, rags, sanitary products, outdoor UV protection fabrics, tent fabrics, floor mats, etc. The market prospect is very promising. At present, the research on polylactic acid and the development of related products in China have just started. This series of articles will make a specific analysis of the foreign patents of polylactic acid in the application of plates and sheets, so as to provide technical reference for relevant research institutions and enterprises in China. The author retrieved a total of 74 patent documents on the application of polylactic acid in layered products from the dewent patent database and the U.S. patent database Third, we will introduce the patent technology related to polylactic acid laminated plate published by derwunt company in 2005: 1. Title: polylactic acid based sheet material and method of making (polylactic acid sheet and its preparation method) source: US (publication date: 2005.05.26, application date: 2003.11.26) inventor: Edward Peter t (US); Best Kenneth W JR (US); Campbell Bruce C (US); Dagan Sandra J (US); Laney Thomas m (US) the purpose of this patent is to provide a single-layer or multi-layer sheet, including a microporous layer that can penetrate low surface tension liquid. The microporous layer contains continuous phase, which is composed of polylactic acid based materials and interconnected micropores. The total absorption capacity of the microporous layer is at least 14cc/M2. The preparation method of the polylactic acid sheet disclosed by the invention is: (a) mixing inorganic particles with molten polylactic acid material, (b) extruding polylactic acid material containing inorganic particles to form a sheet, (c) forming interconnected micropores around inorganic particles by biphasic stretching sheet, and the stretching temperature is lower than 75 ℃. The polylactic acid based material is composed of polylactic acid and compatible comonomer hydroxycarboxylic acid, in which polylactic acid is at least 75 (weight)%; The average particle size of inorganic particles is 0 μ m. It is% of the total weight of the microporous layer, and the inorganic particles can be selected from barium sulfate, calcium carbonate, zinc sulfide, zinc oxide, titanium dioxide, silicon dioxide, aluminum oxide and their compounds. Usage: the invention can be used for recording elements of inkjet printers or other media. 2. Title: biodegradable polyester resin resin composition and films, sheets and other molded articles thereof (biodegradable polyester resin components and their films, sheets and other molded products) source: USA1 (publication date: 2004.02.05, application date: 2003.06.27) issuer: HASEBE Tadashi (JP); Sashida Kazuyuki (JP) family patents: EP (A1), JP (a) the purpose of the invention is to provide a transparent biodegradable polyester resin component with excellent antistatic ability and its film, sheet and other molded products. The biodegradable polyester resin component of the invention comprises: 0 Parts (weight) of antistatic agent, including glycerol monofatty acid ester and alkyl sulfonate; 100 parts by weight of biodegradable polyester resin. Polyester resin is polylactic acid resin or resin mainly includes polylactic acid. 3. Title: biodegradable packaging laminate, a method of producing the packaging laminate, and packaging containers produced from the packaging laminate (biodegradable packaging laminate and its preparation method, and packaging container prepared by it) source: US A1 (publication date: September 12, 2002, application date: May 21, 1999) inventor: Berlin Mikael (SE); Henningsson Karin (SE) family patents: Wo (A1), EP (A1), Se (L), se514845 (C2) the purpose of the invention is to provide a biodegradable packaging laminate with excellent liquid tightness and oxygen resistance. The packaging laminate includes at least one liquid tight layer and one oxygen barrier layer, all of which are biodegradable. The liquid tight layer includes copolymers and homopolymers selected from the following monomers, including lactic acid, ethylene glycol acid, lactide, glycolide, hydroxybutyric acid, hydroxyvaleric acid, hydroxycaproic acid, pentylene lactone, and the first choice for the liquid tight layer is lactide copolymer and homopolymer; The polymer used in the oxygen barrier layer is selected from polyvinyl alcohol, starch and starch derivatives. The biodegradable laminate is suitable for liquid food packaging. 4. Title: aliphatic polyester composites, films made thereof andlaminates thereof (aliphatic polyester component and film and laminate prepared from it) source: US 65213 but irreversibility of conversion process 36 B2 (authorized announcement date: 2003.02.18, application date: 2001.09.25) patentee: tohcello Co Ltd JP the purpose of this invention is to provide a biodegradable, transparent Aliphatic polyester component with excellent heat sealing at low temperature; The invention provides an aliphatic polyester film suitable for any molding method; The invention provides a laminate with good heat sealing strength, peeling performance and excellent adhesion between layers. The aliphatic polyester components disclosed by the invention include (weight):% polylactic acid,% aliphatic polyester, and% tackifier,% tackifier selected from aliphatic cyclic hydrocarbon resin, rosin ester salt, and rosin ester with acid amount ≤ 10. The laminate comprises a base material and an aliphatic polyester component placed on it. The base material is a biodegradable polymer, which can be paper. 5. Title: lactic acid based polymer layered product and molded product source: US B1 (authorized announcement date: 2001.06.19, application date: 1999.08.10) patentee: Dainippon ink Chemicals Inc (JP) the disclosure relates to a lactic acid based polymer layered product with accelerated or controlled biodegradability, which can be used as film or sheet for agriculture or civil engineering, Or used for packaging various foods, beverages, chemicals, sundries, etc., and also involves the molded products prepared by the layered products, especially films, sheets, packaging bags, or light containers, injection containers, blow molding containers, etc. obtained by heating and molding of films or sheets. The purpose of the invention is to provide a lactate based polymer layered product with little lactide leakage and fast degradation speed in the storage of molding or molded products, and the molded products obtained therefrom. The independent claim of the invention is: a layered product of lactic acid based polymer, including (I) a degradation accelerator barrier layer, which is prepared from lactic acid based polymer (b), the polymer (b) contains no more than 0.1 (WT)% lactide laminated on one or two base layers (II), the base layer (II) is prepared from lactic acid based polymer (a), and the polymer (a) includes a degradation accelerator prepared from lactide and/or the content is 0 (WT)% organic acid, in which the ratio of barrier layer to base layer thickness is 0. Physical methods, chemical methods or organic combination of different methods are adopted through mechanical equipment 02:1.6. Title: heat sealable lactic acid based polymer laminates source: us a (authorized announcement date: November 28, 2000, application date: May 21, 1998) patentee: Dainippon ink Chemicals Inc JP the purpose of this invention is to provide a lactic acid based polymer laminate with heat resistance higher than 60 ℃, high heat sealing strength and good biodegradability, which can be used in various films, sheets and packaging containers, It is mainly suitable for packaging all kinds of food, drinks, drugs, sundries, etc., as well as packaging containers such as packaging bags, packaging boxes and light containers formed by heating laminates. The independent claim of the invention is: a heat sealed lactic acid based polymer laminate, which includes: a base layer (I) made of crystalline lactic acid based polymer (a) with a melting point of at least 120 ℃ to have "fire performance" that can avoid material flashover, and a heat seal layer (II) made of amorphous lactic acid based polymer with a softening point of ℃, wherein one side of the heat seal layer is laminated on one side of the base layer, and the other side of the heat seal layer is the outer surface of the laminate