WO2007022732A1 - A composite slow-release coated fertilizer without environmental pollution - Google Patents

Abstract

This invention discloses a composite slow-release coated fertilizer without environmental pollution. The slow-release coated fertilizer is composed of fertilizer core 1 and outer coated layer, wherein the coated layer comprises (a) a sulfur layer 2, (b) a sulfur contained degradable polymer mixture layer 3 and/or a degradable polymer layer 4, and (c) an optional high-barrier organic layer 5. The sulfur layer is the inner layer or middle layer. The degradable polymer is selected from one or more of amino resin, acetal resin of polyvinyl alcohol and its copolymer, unsaturated oil resin and natural polymer as well as its derivative. The high-barrier organic layer is preferably nonpolar organic layer composed of nonpolar low molecular weight organic substance and /or nonpolar polymer. The nonpolar organic layer with the thickness of 0-15μm is preferably adjacent to sulfur layer. The slow-release coated fertilizer has low cost, long release time, high reliability and brings no pollution to environment.

Description

 Environmentally friendly composite coated slow release fertilizer

 Technical field

 The invention relates to a coated slow release fertilizer, in particular to an environmentally friendly composite coated slow release fertilizer, belonging to the field of fertilizer industry.

 Background technique

 At present, slow release fertilizer is the development direction of the world fertilizer industry. Among them, coated slow release fertilizer is the development focus of slow release fertilizer, but the envelope of non-degradable coated slow release fertilizer will be polluted by the environment, so the environmental protection package of degradable envelope is developed. Membrane slow release fertilizer meets the requirements of environmental protection and social sustainable development, and will become the mainstream of slow release fertilizer in the future.

 However, the degradable material has a high permeable and transdermal speed, so the release period of the prepared degradable coated slow-release fertilizer is very short, generally only a few days, such as the sustained release of the envelope type using a urea-formaldehyde resin coating. A coated slow release fertilizer coated with fertilizer and lignin modified material. Increasing the release period is a difficult problem to be solved for the degradable coated slow release fertilizer, and it is also the key to the practical application of the degradable coated slow release fertilizer in the future. ,

 Summary of the invention

 SUMMARY OF THE INVENTION It is an object of the present invention to provide an environmentally-protected composite coated slow release fertilizer which has a long release period and which is completely or almost completely degradable.

 The technical solution for achieving the object of the present invention is: an environmentally friendly composite coated slow release fertilizer consisting of a fertilizer core and a coating on the outer side of the fertilizer core, the envelope comprising: (a) a sulfur film layer, (b) a sulfur-containing film Degrading the polymer mixture film layer and/or the degradable polymer film layer, with or without (c) a high barrier organic film layer; wherein the sulfur film layer is the inner or intermediate layer of the entire envelope.

 In the film of the sulfur-containing degradable polymer mixture of the environmentally friendly composite coated slow release fertilizer of the present invention, the average mass fraction of sulfur may be 0% to 95%, preferably 20% to 90%.

 The degradable polymer used in the environmentally friendly composite coated slow release fertilizer of the invention is a water-insoluble degradable polymer, and may be an amino resin, an acetal resin of polyvinyl alcohol and a copolymer thereof, an unsaturated oleoresin and One or more of natural polymers and derivatives thereof. Among them, the natural polymer and the derivative thereof may be one or more of nitrocellulose, shellac, cellulose acetate, crosslinked starch, chitin derivative, lignin derivative, and the like.

The high barrier organic film layer in the environmentally friendly composite coated slow release fertilizer coating of the present invention is preferably a non-polar organic film layer. The material of the non-polar organic film layer may be a non-polar low molecular weight organic substance and/or a non-polar polymer, wherein the non-polar organic film layer is preferably a non-polar low molecular weight organic substance. The non-polar organic film layer is preferably adhered to the sulfur film layer, and the non-polar organic film layer is preferably not the outermost film layer of the envelope. The non-polar low molecular weight organic substance may be one or more of a wax having a melting point of 40 ° C, a melting point or a softening point of 40 ° C and a polyolefin or polystyrene having a molecular weight of ≤2000 and a petroleum resin having a softening point of 40 Å. The non-polar polymer may be a polyolefin or a polyphenylene Ethylene, butadiene rubber, natural rubber, polyisoprene rubber, styrene butadiene rubber, butyl rubber, ethylene propylene rubber and ethylene propylene diene rubber, styrene butadiene styrene block copolymer and styrene One or more of an isoprene-styrene block copolymer and the like.

 The high barrier organic film layer of the environmentally friendly composite coated slow release fertilizer of the present invention may contain a sustained release modifier. The sustained release modifier is preferably a polar organic substance which is soluble in the material of the high barrier organic film layer.

 The environmentally friendly composite coated slow-release fertilizer of the invention has a total average thickness of 10~180 ^ m, wherein the average thickness of the sulfur film layer can be from 1 to 100 m, the degradable polymer film layer and the sulfur-containing degradable polymerization layer. The total average thickness of the film mixture layer may be 5 to 180 / m, the total average thickness of the high barrier organic film layer may be 0 to 15 m, and the average thickness of the outer layer of the sulfur film layer is not less than 3 m; The total average thickness of the sulfur-containing degradable polymer mixture film layer is 0 to 100 m, and the total average thickness of the degradable polymer film layer is 0 to 100 m.

 Wherein, the total average thickness of the coating is preferably from 20 to 90 m, wherein the average thickness of the sulfur film layer is preferably from 8 to 60/m, and both the degradable polymer film layer and the sulfur-containing degradable polymer mixture film layer are The total average thickness is preferably 8~50/m, the total average thickness of the high barrier organic film layer is preferably 0~10/m, and the average thickness of the outer layer of the sulfur film layer is preferably not less than 5/m; The total average thickness of the film layer of the sulfur degradable polymer mixture is preferably from 8 to 50 μ, and the total average thickness of the degradable polymer film layer is preferably from 0 to 35 μm.

 The environmental protection composite coated slow release fertilizer of the invention uses degradable polymer and sulfur as all or main coating materials, and all the coating materials have no pollution to the environment or little pollution, so it is a completely or almost completely environmentally friendly slow release fertilizer. When the coating has no composite non-polar polymer film layer, it is a completely environmentally friendly slow-release fertilizer.

The environmentally friendly composite coated slow release fertilizer of the invention is combined with a sulfur film layer by using a degradable polymer film layer and/or a sulfur-containing degradable polymer mixture film layer, because the sulfur film layer has high barrier to water and fertilizer, and at the same time Since the degradable polymer is water-insoluble, it does not dissolve in the soil when the fertilizer is applied to the soil, and the degradable polymer film layer and/or the sulfur-containing degradable polymer mixture film layer can always be used throughout the use process. The membrane barrier effect, and thus the degradable coated slow release fertilizer of the present invention using a degradable polymer as a coating material can have a long release period. At the same time, since the price of sulfur is lower than that of the fertilizer, the cost of the environmentally friendly composite coated slow release fertilizer of the present invention can be low. In particular, urea-formaldehyde resins and melamine-formaldehyde resins are relatively inexpensive degradable polymers, which are much cheaper than conventional refractory polymers, and which are themselves slow-release nitrogen fertilizers, urea-formaldehyde resins and melamine-formaldehyde resins. The nitrogen content is about 30% and 54% respectively, and the nitrogen content of the melamine-formaldehyde resin is higher than the nitrogen content of urea (about 45%). Therefore, the urethane resin and the melamine-formaldehyde resin are used as the coating material. The invention relates to an environmentally-friendly composite coated slow-release fertilizer which is completely fertilizer-fermented slow-release fertilizer with high fertilizer content and low cost. For example, according to the cost index of pure fertilizer, the cost index of sulfur is about 50, the cost index of urea-formaldehyde resin and melamine-formaldehyde resin is about 450 and 600, respectively, 85% of fertilizer, 10% of sulfur and urethane resin. Or the 5% melamine-formaldehyde resin composition of the environmentally friendly composite coated slow release fertilizer of the present invention is calculated as an example, and their total cost index is about 112.5 and 120, only 12.5%~20% higher than the cost of pure fertilizer, can be used as a common agricultural field fertilizer. In particular, when the environmentally friendly composite coated slow release fertilizer of the present invention is combined with a sulfur film layer by a sulfur-containing degradable polymer mixture film layer, the barrier property of the sulfur-containing degradable polymer mixture film to water and fertilizer is simpler than The degradable polymer film layer is strong, especially when the sulfur content is 髙 (such as 80%~90%), the barrier property to water and fertilizer is strong, so there is a film layer of sulfur-containing degradable polymer mixture in the coating film. The environmentally friendly composite coated slow release fertilizer of the invention has a longer release period, especially when the sulfur-containing degradable polymer mixture film layer is in close contact with the sulfur film layer. At the same time, in the case of effectively protecting the sulfur film layer, the use of the sulfur-containing degradable polymer mixture film layer can further reduce the amount of the degradable polymer, and the cost is lower.

 The invention can be made in the coating of the environmentally friendly composite coated slow release fertilizer of the present invention by recombining a very thin high barrier organic film layer (the amount of which is small, which is smaller than the amount of the sulfur film layer which can be separately protected). The release period of the environmentally friendly composite coated slow release fertilizer is further prolonged, especially when the high barrier organic film layer is a non-polar organic film layer, and the non-polar organic film layer is closely attached to the sulfur film layer, the effect is obvious. Therefore, the release period of the environmentally friendly composite coated slow release fertilizer of the present invention in which the non-polar organic film layer is compounded in the envelope can be long. Moreover, a polar organic substance or other slow release modifier which is soluble in the high barrier organic film layer material is added to the high barrier organic film layer, and the release period can be freely adjusted by controlling the addition amount, and the coating film is changed more than the coating film. The method of adjusting the release period of the total thickness of the layer is more efficient and more economical. In particular, if a non-polar low molecular weight organic material is used as a non-polar organic film layer, such as wax, polyolefin or polystyrene having a molecular weight of ≤2000, and petroleum resin, non-polar low molecular weight organic substances are generally available in the environment. Biodegradable, therefore, the environmentally friendly composite coated slow release fertilizer of the present invention is still a completely environmentally friendly slow release fertilizer. Even if the non-polar organic film layer material uses a non-polar polymer, since it is used in an amount of only about 1%, it has little environmental pollution compared with the slow-release fertilizer of the prior art, and has obvious advantages. .

 DRAWINGS

 BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a structural view of a spherical fertilizer core 1 - a sulfur-containing degradable polymer mixture film - a sulfur film layer 2 - a sulfur-containing degradable polymer mixture film layer 3 of the environmentally friendly composite film type slow release fertilizer of the present invention.

 Fig. 2 is a structural view of a spherical fertilizer core 1 - sulfur film layer 2 - sulfur-containing degradable polymer mixture film layer 3 of the environmentally friendly composite film type slow release fertilizer of the present invention.

 Fig. 3 is a structural view of a spherical fertilizer core 1 - a degradable polymer film layer 4 - a sulfur film layer 2 - a degradable polymer film layer 4 of the environmentally friendly composite film type slow release fertilizer of the present invention.

 Fig. 4 is a structural view of a spherical fertilizer core 1 - sulfur film layer 2 - a degradable polymer film layer 4 of the environmentally friendly composite coated slow release fertilizer of the present invention.

 Fig. 5 is a structural view of a spherical fertilizer core 1 - sulfur-degradable polymer mixture film 3 - sulfur film layer 2 - degradable polymer film layer 4 of the environmentally friendly composite film type slow release fertilizer of the present invention.

Figure 6 is a spherical fertilizer core 1 of the environmentally friendly composite coated slow release fertilizer of the present invention, a degradable polymer film layer 4 sulfur Sulfide layer 2 - structure diagram of film layer 3 of sulfur-containing degradable polymer mixture.

 7 is a spherical fertilizer core 1 of a sulfur-containing degradable polymer mixture layer of the environmentally friendly composite coated slow release fertilizer of the present invention. 3 - a sulfur film layer 2 - a sulfur-containing degradable polymer mixture film layer 3 - a degradable polymer Structure of the film layer 4.

 Fig. 8 is a structural view of a spherical fertilizer core 1 - sulfur film layer 2 - sulfur-degradable polymer mixture film layer 3 - degradable polymer film layer 4 of the environmentally friendly composite film type slow release fertilizer of the present invention.

 9 is a spherical fertilizer core 1 of a sulfur-containing degradable polymer mixture layer 3 - a sulfur film layer 2 - a high barrier organic film layer 5 - a sulfur-containing degradable polymer mixture of the environmentally friendly composite coated slow release fertilizer of the present invention Structure of the film layer 3.

 Figure 10 is a spherical fertilizer core 1 of a sulfur-containing degradable polymer mixture of the environmentally friendly composite coated slow release fertilizer of the present invention. 3 - Sulfur film layer 2 - High barrier organic film layer 5 - Degradable polymer film layer 4 Structure diagram.

 Figure 11 is a structural view of a spherical fertilizer core 1 - a high barrier organic film layer 5 - a sulfur film layer 2 - a sulfur-containing degradable polymer mixture film layer 3 of the environmentally friendly composite film type slow release fertilizer of the present invention.

 Fig. 12 is a structural view of a spherical fertilizer core 1 - a high barrier organic film layer 5 - a sulfur film layer 2 - a degradable polymer film layer 4 of the environmentally friendly composite film type slow release fertilizer of the present invention.

 detailed description

 The environmentally friendly composite coated slow release fertilizer of the present invention is composed of a fertilizer core 1 and a coating film outside the fertilizer core, and the coating film comprises (a) a sulfur film layer 2, (b) a sulfur-containing degradable polymer mixture film layer 3 and I or Degradable polymer film layer 4, with or without (c) high barrier organic film layer 5; wherein the sulfur film layer is the inner or intermediate layer of the entire envelope.

 The fertilizer core of the environmentally friendly composite coated slow release fertilizer of the invention may be nitrogen fertilizer, phosphate fertilizer, potassium fertilizer or compound fertilizer. The shape of the fertilizer core may be granular, flake, or the like, but it is preferably granular, and preferably spherical.

 The film of the sulfur-containing degradable polymer mixture in the present invention means a film layer of a mixture of sulfur and a degradable polymer. The coating of the environmentally friendly composite coated slow release fertilizer of the present invention may be a composite film layer of a sulfur-containing degradable polymer mixture film layer and a sulfur film layer, and such a composite film layer is preferred. At this time, the structure of the slow release fertilizer can be as shown in Fig. 1 and Fig. 2, and the structure of Fig. 1 is superior to that of Fig. 2.

 The envelope of the environmentally friendly composite coated slow release fertilizer of the present invention may also be a composite film layer of a degradable polymer film layer and a sulfur film layer. At this time, the structure of the slow-release fertilizer can be as shown in Fig. 3 and Fig. 4, and the structure of Fig. 3 is superior to that of Fig. 4.

The coating of the environmentally friendly composite coated slow release fertilizer of the present invention may also be a composite film layer of a sulfur-containing degradable polymer mixture film layer, a degradable polymer film layer and a sulfur film layer. Wherein, the structure of the sulfur-containing degradable polymer mixture film layer is close to the sulfur film layer, and the film layer of the sulfur-containing degradable polymer mixture is close to the surface of the sulfur film layer than the sulfur-containing degradable polymer mixture film layer. The structure close to the outer surface of the sulfur film layer is excellent. At this time, the structure of the slow release fertilizer can be as shown in Fig. 5, Fig. 6, Fig. 7, and Fig. 8. Among them, Fig. 5 and Fig. 7 are preferred among the above four structures, and the structure of Fig. 7 is superior to the structure of Fig. 5. In addition, it is also possible to have a structure of other combinations. The coating of the environmentally friendly composite coated slow release fertilizer of the present invention can further compound a high barrier organic film layer in each of the above three types of structures. The high barrier organic film layer refers to a film layer having a lower transmittance to water and fertilizer than the degradable polymer film layer, that is, the high barrier organic film layer material has a lower transmittance to water and fertilizer than in the envelope film. The permeability of water and fertilizer used by degradable polymers. Since the non-polar organic film layer has a low transmittance to water and fertilizer, water and fertilizer are mainly transmitted through the film defect, so the high-barrier organic film layer in the environmentally friendly composite coated slow release fertilizer coating of the present invention It is preferably a non-polar organic film layer. Further, the non-polar organic film layer is preferably adhered to the sulfur film layer, and the non-polar organic film layer is preferably not the outermost film layer of the envelope.

 When there is no non-polar organic film layer in the envelope, the structure of the sulfur-containing degradable polymer mixture film layer adhering to the sulfur film layer is a preferred structure. However, when there is a non-polar organic film layer in the coating, the non-polar organic film layer is closely attached to the sulfur film layer, and the sulfur-containing degradable polymer mixture film layer is more closely adhered to the sulfur film layer, and the non-polar organic film layer is more preferred. The structure closely adjacent to the sulfur film layer is a more preferable structure. The inner surface and the outer surface of the sulfur film layer may be combined with a non-polar organic film layer. Since the non-polar low molecular weight organic substance has a low melting point, the non-polar low molecular weight organic film layer is generally on the outer surface of the sulfur film layer; the non-polar polymer is on the inner surface and the outer surface of the sulfur film layer, However, it is generally only available on one side, and the barrier effect exerted on the inner surface is better. In the structure in which the non-polar organic film layer is in close contact with the sulfur film layer, when there is a film layer of the sulfur-containing degradable polymer mixture in the coating film, the film layer of the sulfur-containing degradable polymer mixture is closely attached to the non-attached non-paste layer. The other surface of the sulfur film layer of the polar organic film layer and/or the structure which is in close contact with the surface of the non-polar organic film layer is a more optimized structure among them.

 The structure shown in Fig. 9 to Fig. 12 is four representative structures of the environmentally friendly composite coated type slow release fertilizer of the present invention which is compounded with a high barrier organic film layer. It can also be a structure of other combinations.

 Of course, it is also possible to change the structure based on the structures of Figs. 1 to 12. For example, it may be a multiple composite structure of the envelope structure shown in Figs. 1 to 12, or a multiple composite structure in which the envelope structures shown in Figs. 1 to 12 are combined with each other. However, these multiple composite structures are not preferred structures from a process perspective.

 In the film of the sulfur-containing degradable polymer mixture of the environmentally friendly composite coated slow-release fertilizer of the present invention, the average mass fraction of sulfur may be between 0% and 95%. However, when the sulfur content is too low, the effect of improving the barrier property of the film layer is not obvious, but when the content is too high, the toughness of the film layer is low and brittle, so it is preferably between 20% and 90%, preferably 60%. Between ~90%. If necessary, a certain amount of plasticizer may be added to the film layer of the sulfur-containing degradable polymer mixture to increase the toughness of the film. At the same time, it is also possible to form a sulfur-containing gradient distribution in the film layer of the sulfur-containing degradable polymer mixture, for example, the sulfur content in the film layer of the sulfur-containing degradable polymer mixture outside the sulfur film layer (ie, opposite to the direction toward the fertilizer core). Gradually decreasing from the inside to the outside, the outer layer has a low sulfur content to give the outer layer high toughness. When the sulfur content of the sulfur-containing degradable polymer mixture film layer outside the sulfur film layer is high, for example, 80% or more, the sulfur-containing degradable polymer mixture film layer may have a thin layer (such as 3~10 ί ΐη). A layer of degradable polymer film to better protect the inner film layer.

The biodegradable composite film type slow release fertilizer of the invention adopts a degradable polymer, which can be an amino resin or a polyethylene. One or more of a acetal acetal resin, an unsaturated oleoresin, a natural polymer, and a derivative thereof, of an alcohol and a copolymer thereof. Among them, the natural polymer and its derivative may be one or more of nitrocellulose, shellac, cellulose acetate, crosslinked starch, chitin derivative, and lignin derivative. The degradable polymer in the environmentally friendly composite coated slow release fertilizer coating of the present invention is water-insoluble, or although the prepolymer used is water-soluble, the degradable polymer in the finally formed film layer should be non-water soluble. The prepolymer such as a urea-formaldehyde resin and a melamine-formaldehyde resin may be water-soluble, but the urea-formaldehyde resin and the melamine-formaldehyde resin formed by curing cross-linking become water-insoluble.

 Among the degradable polymers, amino resins are preferred, especially urea-formaldehyde resins and melamine-formaldehyde resins (including modified urea-formaldehyde resins and modified melamine-formaldehyde resins) at low prices, and they are used as degradable polymerization. The environmentally-friendly composite coated slow-release fertilizer prepared by the material of the coating material is a complete fertilizer-fermented slow-release fertilizer with high fertilizer content and low product cost; in particular, the resistance of melamine-formaldehyde resin to water and fertilizer The permeability is relatively strong, and its degradation rate is slow, and its envelope can exert an envelope barrier effect for a long period of time. Further, the unsaturated oleoresin is a resin obtained by crosslinking an unsaturated oil, and a solvent may not be used in the process of coating the unsaturated oil, so that an unsaturated oleoresin may also be preferred. Unsaturated oil refers to a natural oil that contains a double bond in the molecular structure and can undergo a cross-linking reaction, such as tung oil, soybean oil, linseed oil or dehydrated castor oil. Among them, tung oil is a lower-priced natural unsaturated oil. The tung oil resin film formed in combination has a strong barrier property against water and fertilizer, and is a preferred unsaturated oil. Further, the acetal acetal resin (50% acetal degree) and nitrocellulose of the water-insoluble polyvinyl alcohol and its copolymer are also degradable coating materials which are considered to be selected. The acetal resin of polyvinyl alcohol and its copolymer may be a formal resin, a acetal resin or a butyral resin of polyvinyl alcohol and a copolymer thereof.

 In order to adjust the properties of the sulfur-containing degradable polymer mixture film layer and the degradable polymer film layer, such as toughness, a low molecular organic substance such as a sulfur-containing degradable polymer mixture film layer and a degradable polymer film layer may be added. A small amount of a bactericide or a bacteriostatic agent may be added to the aforementioned plasticizer or the like.

 In order to further improve the release period of the environmentally friendly composite coated slow-release fertilizer of the present invention, it is preferable to compound a high-barrier organic film layer in the coating, and the high-barrier organic film layer material may be a ruthenium-blocking low-molecular organic substance or It is a highly barrier-resistant, refractory polymer. The high-barrier low-molecular organic substance may be a low-permeability organic substance (relative to a degradable polymer) such as pitch and a mixture thereof and rosin (ester) and a mixture thereof, and the high-barrier refractory polymer may be propylene. Low permeability polymer (relative to degradable polymers) such as nitrile-butadiene-styrene copolymer (ABS), nitrile rubber, unsaturated polyester, polyurethane and epoxy resin. The high-barrier organic film layer is preferably a non-polar organic film layer, and the non-polar organic film layer is preferably in close contact with the sulfur film layer, and is preferably not the outermost film layer of the envelope. The material of the non-polar organic film layer may be a non-polar low molecular weight organic substance and an I or a non-polar polymer, wherein the non-polar organic film layer is preferably a non-polar low molecular weight organic substance.

In the environmentally friendly composite coated slow release fertilizer of the present invention, the nonpolar polar molecular layer used in the nonpolar organic film layer has The organic substance may be one or more of a wax having a melting point of ≥ 40, a melting point or a low molecular weight polyolefin or polystyrene having a melting point of ≥ 40 ° C and a molecular weight of ≤ 2000, and a petroleum resin having a softening point of ≥ 40 Å. The wax may be a petroleum wax, a synthetic wax, a natural wax, a mineral wax or the like; the low molecular weight polyolefin may be a polyethylene wax, or may be a low molecular weight polypropylene, a low molecular weight polyisobutylene or the like. Of course, the molecular weight of the low molecular weight polyolefin or polystyrene may also be ≥2000. The melting point or softening point of the non-polar low molecular weight organic substance is preferably higher, ≥ 60'. Preferably, it is preferably ≥85 °C.

 In the environmentally friendly composite coated slow release fertilizer of the invention, polyolefin, polystyrene, butadiene rubber, natural rubber, polyisoprene rubber, styrene butadiene rubber, butyl rubber, ethylene propylene rubber and ternary can be used. One or more non-polar polymers such as ethylene propylene rubber, styrene-butadiene-styrene block copolymer and styrene-isoprene-styrene block copolymer as non-polar organic Film material.

 A certain amount of polar organic substance soluble in the high-barrier organic film layer material may be added to the high-barrier organic film layer, and the release period of the environmentally-friendly composite coated type slow-release fertilizer of the present invention can be freely adjusted by controlling the amount of the organic substance added thereto. . For example, adding wax-soluble additives with polar groups such as chlorinated paraffins, rosins and their esters, asphalt, etc. to paraffin; adding polar plasticizers such as dibutyl phthalate to non-polar polymers Classes, polyol esters, etc. The polar organic substance may be a polar low molecular weight organic substance (as exemplified above), or may be a polar prepolymer or a polymer such as an unsaturated polyester prepolymer added to the paraffin wax, which is crosslinked by coating. Of course, the addition of water-soluble salts, starch, wood flour, plant chips, clay, talc, molecular sieve powder or bone powder to the high-barrier organic film layer can improve the permeability of the high-barrier organic film layer to water and fertilizer. The addition period can also adjust the release period of the environmentally friendly composite coated slow release fertilizer of the present invention.

 The sulfur film layer on the outer surface of the fertilizer core should be complete or substantially intact, and it is best not to have a large amount of damage, so the sulfur film layer should reach a certain average thickness. The average thickness of the sulfur film layer may be between l and 100/m, but it is preferably from 8 to 60 m. The total average thickness of the entire envelope should be able to bear the expansion force generated by the water swell of the fertilizer core, so that the overall envelope is broken, so the total average thickness of the envelope can be between 10 and 180 m. The total average thickness of the coating is preferably from 20 to 90 m, depending on the preferred average thickness of the sulfur film layer of from 8 to 60 m. The total average thickness of both the degradable polymer film layer and the sulfur-containing degradable polymer mixture film layer may be 5 to 180 m, but is preferably 8 to 50 m. The total average thickness of the high-barrier organic film layer may be 0 to 15 m, preferably 0 to 10/m. The average thickness of the outer layer of the sulfur film layer should not be less than 3 m, preferably not less than 5 // m. Further, the total average thickness of the film layer of the sulfur-containing degradable polymer mixture and the total average thickness of the degradable polymer film layer may each be 0 100 / m, but the total average thickness of the film layer of the sulfur-containing degradable polymer mixture is 8~50 m is preferred, and the total average thickness of the degradable polymer film layer is preferably 0 to 35 m.

Of course, the total average thickness of the envelope, the average thickness of the sulfur film layer, the total average thickness of both the degradable polymer film layer and the sulfur-containing degradable polymer mixture film layer, and the total average thickness of the sulfur-containing degradable polymer mixture film layer The total average thickness of the degradable polymer film layer and the total average thickness of the high-barrier organic film layer can be compared with the above The respective upper limit values are larger. The greater these thicknesses, the longer the release period of the environmentally friendly composite coated slow release fertilizer. Due to the different surface properties between the sulfur, the degradable polymer and the high barrier organic film layer material, in order to adjust the mutual wetting and spreading film formation between them, the degradable polymer, the sulfur-containing degradable polymer and the ruthenium may be used. A surfactant is added to the coating liquid of the organic film layer.

 In addition, various other additives may be added to the sulfur film layer, the sulfur-containing degradable polymer mixture film layer, the degradable polymer film layer and the antimony-barrier organic film layer in the environmentally-friendly composite coated slow release fertilizer coating of the present invention. The additive is added for purposes such as further adjusting a certain property of each film layer or reducing cost.

 Hereinafter, the environmentally friendly composite coated slow release urea of the present invention using urea as a fertilizer core is taken as an example to illustrate the specific implementation method and invention effect of the environmentally friendly composite coated slow release fertilizer of the present invention. The slow release property of the environmentally friendly composite coated slow release urea of the present invention is evaluated by the dissolution method in water. The dissolution method in water is the determination of the dissolution rate of urea in water in the environmentally friendly composite coated slow release urea of the present invention, and the specific method is as follows: 10 g The environmentally friendly composite coated slow release urea of the invention is immersed in 200 ml of water and immersed at a constant temperature of 25 ° C to measure the initial dissolution rate and the average differential dissolution rate. The initial dissolution rate ^ refers to the percentage of urea dissolved in the first 24 hours of immersion in the total mass of urea in the environmentally friendly composite coated slow release urea of the invention, and the average differential dissolution rate is 3⁄4^ from the soaking The average amount of urea dissolved per day from 2 days to 7 days is 10% of the total mass of urea in the environmentally-friendly composite coated slow-release urea of the present invention. According to the initial dissolution rate ^ and the average differential dissolution rate ^, the release period of the environmentally friendly composite coated slow release urea of the present invention in water is calculated (day):

Ψ

 Example 1

The granular industrial urea having a particle diameter of 2.0 to 4.0 mm is introduced into the fluidized bed coating device, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 80 °C. The urea-formaldehyde resin prepolymer aqueous solution (urea resin prepolymer is urea: formaldehyde is prepared by reacting urea with formaldehyde in a molar ratio of 1:2) and molten sulfur at about 150 °C from two different nozzles simultaneously to granular urea. The surface is slowly sprayed, and by controlling the spray flow ratio thereof, the average mass fraction of sulfur in the formed sulfur-containing urea-formaldehyde resin mixture layer is 70%, and spraying until the formed layer of the sulfur-containing urea-formaldehyde resin mixture reaches the final product quality. 6% of the total mass of the environmentally-friendly composite coated slow-release urea, drying to remove water in the film. Then, stop spraying the urea-formaldehyde resin prepolymer aqueous solution, and continue to spray about 15 TC of molten sulfur on the surface of the sulfur-containing urea-formaldehyde resin mixture film layer until the quality of the formed sulfur film layer reaches the final product environmentally friendly composite coated type slow-release urea total. 7% of the quality. Then, a sulfur-containing urea-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the sulfur film layer. The urea-formaldehyde resin prepolymer is prepared by reacting urea with formaldehyde in a molar ratio of 1:1.6, and sulfur: urea-formaldehyde resin prepolymer. The mass ratio is 2:3) until the film quality of the layer containing the thiourea resin mixture is 6% of the total mass of the final product environmentally friendly composite coated slow release urea. Drying removes the film layer Water, and the urea-formaldehyde resin in the film layer is fully cured, that is, an environmentally friendly composite coated type slow-release urea is obtained. The release period of the prepared environmentally-friendly composite coated slow release urea was 145 days.

 Example 2

 The granular industrial urea having a particle diameter of 2.0 to 4.0 mm is introduced into the fluidized bed coating device, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 90 °C. About 150 熔融 of molten sulfur is slowly sprayed on the surface of the urea until the quality of the sulfur film reaches 7% of the total mass of the final product environmentally friendly composite coated slow release urea. Then, a sulphur-containing melamine-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the sulfur film layer (melamine-formaldehyde resin prepolymer is prepared by reacting melamine with a molar ratio of 1:3 melamine and formaldehyde, sulfur: melamine one The mass ratio of the formaldehyde resin prepolymer is 7:3) until the film quality of the formed sulfur-containing melamine-formaldehyde resin mixture reaches 8% of the total mass of the final product environmentally friendly composite coated slow release urea. The water in the film layer is removed by drying, and the melamine-formaldehyde resin in the film layer is sufficiently cured to obtain an environmentally friendly composite coated type slow-release urea. The release period of the environmentally friendly composite coated slow release urea was 112 days.

 Example 3

 The granular industrial urea having a particle diameter of 2.0 to 4.0 mm is introduced into the fluidized bed coating device, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 90 °C. Spraying a melamine-formaldehyde resin prepolymer aqueous solution (melamine-formaldehyde resin prepolymer is prepared by reacting melamine:melamine with a formaldehyde molar ratio of 1:4) onto formaldehyde, until the layer of melamine-formaldehyde resin film is formed. The layer quality reaches 2% of the total mass of the final finished environmentally friendly composite coated slow release urea, and the water is removed by drying. Then, molten sulphur of about 150 ° C is sprayed on the surface of the melamine-formaldehyde resin film layer until the quality of the formed sulfur film layer reaches 11% of the total mass of the final product environmentally friendly composite coated slow release urea. Finally, a melamine-formic acid resin prepolymer aqueous solution is sprayed on the surface of the sulfur film layer (the melamine-formic acid resin prepolymer is prepared by reacting melamine with a formaldehyde molar ratio of 1:3 and melamine) until the layer of melamine is formed. The quality of a formaldehyde resin film layer reaches 4% of the total quality of the final product environmentally friendly composite coated slow release urea. The water is removed from the film layer by drying, and the melamine-formaldehyde resin in the film layer is sufficiently cured to obtain an environmentally-friendly composite film-type slow-release urea. The release period of the environmentally-friendly composite membrane-type slow-release urea produced was 115 days.

 Example 4

The granular industrial urea with a particle size of 2.0~4.0nm is added to the fluidized bed coating equipment, and the granular urea is in a boiling state. The temperature of the granular urea in the fluidized bed is maintained at 9 (TC. The molten sulfur is about 150 ° C slow. Slowly spray on the urea surface until the quality of the formed sulfur film reaches 16% of the total mass of the final product environmentally friendly composite coated slow release urea. Then, spray the melamine-formaldehyde resin prepolymer aqueous solution on the surface of the sulfur film (melamine one). The formaldehyde resin prepolymer is prepared by reacting melamine with a formaldehyde molar ratio of 1:2.7 in melamine and formaldehyde, until the quality of the formed melamine-formaldehyde resin film reaches the final quality of the final product environmentally friendly composite coated slow release urea. 4%. The water is removed from the film layer by drying, and the melamine-carboxylic acid resin in the film layer is sufficiently cured to obtain an environmentally-friendly composite film-type slow-release urea. The release period of the environmentally friendly composite coated slow release urea was 117 days.

 Example 5

 The granular industrial urea having a particle diameter of 2.0 to 4.0 mm is introduced into the fluidized bed coating device, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 50 °C. The nitrocellulose solution (the solvent is a mixed solvent of ethanol, acetone and amyl acetate) and the molten sulfur at about 150 °C are simultaneously sprayed from the two different nozzles to the surface of the granular urea, respectively, by controlling their spraying. The flow ratio is such that the average mass fraction of sulfur in the formed sulfur-containing nitrocellulose mixture film layer is 80%, and the film quality of the layer of sulfur-containing nitrocellulose mixture formed until the final layer of the environmentally friendly composite coated type slow-release urea is reached. 6% of the total mass, dry to remove the solvent in the film. Then, stop spraying the nitrocellulose solution, and continue to spray 150 ° C molten sulfur on the surface of the sulfur-containing nitrocellulose mixture membrane layer until the quality of the formed sulfur film layer reaches the total quality of the final product environmentally friendly composite coated slow release urea. 8%. Finally, the nitrocellulose solution is sprayed on the surface of the sulfur film layer until the quality of the formed nitrocellulose film reaches 2% of the total mass of the final product environmentally friendly composite coated slow release urea. The solvent in the film layer is sufficiently dried to obtain an environmentally friendly composite coated type slow-release urea. The release period of the environmentally friendly composite coated slow release urea was 134 days.

 Example 6

 The granular industrial urea having a particle diameter of 2.0 to 4.0 mm is introduced into the fluidized bed coating device, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 80 °C. Spraying a melamine-formaldehyde resin prepolymer aqueous solution (melamine-formaldehyde resin prepolymer is prepared by reacting melamine:melamine with a formaldehyde molar ratio of 1:3.5) with formaldehyde until the surface of the melamine-formaldehyde resin film is formed. The final product is 1.5% of the total mass of the environmentally-friendly composite coated slow-release urea, and the water is removed by drying. Then, about 150 熔融 of molten sulfur is sprayed on the surface of the melamine-formaldehyde resin film layer until the quality of the formed sulfur film layer reaches 8% of the total mass of the final product environmentally friendly composite coated slow release urea. Finally, a melamine-formaldehyde resin prepolymer aqueous solution (melamine-formaldehyde resin prepolymer is prepared by reacting melamine:melamine with a molar ratio of 1:3 and formaldehyde) and 150 Å of molten sulfur are respectively different from two groups. The nozzles are simultaneously sprayed onto the surface of the sulfur film layer, and by controlling the spray flow ratio thereof, the average mass fraction of sulfur in the formed sulfur-containing melamine-formaldehyde resin mixture layer is 80% until the formed layer of sulfur-containing melamine is formed. The film quality of the formaldehyde resin mixture reaches 7% of the total mass of the final product environmentally friendly composite coated slow release urea. The water is removed from the film layer by drying, and the melamine-formaldehyde resin in the film layer is sufficiently cured to obtain an environmentally-friendly composite film-type slow-release urea. The release period of the environmentally-friendly composite coated slow release urea was 118 days.

 Example 7

The granular industrial urea having a particle diameter of 2.0 to 4.0 mm is introduced into the fluidized bed coating device, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 90 °C. Preconcentration of sulphur-containing melamine-formaldehyde resin Aqueous solution (melamine-formaldehyde resin prepolymer is prepared by reacting melamine: melamine with a formaldehyde molar ratio of 1:3 and formaldehyde, sulfur: melamine-formaldehyde resin prepolymer has a mass ratio of 4:1) sprayed on the urea surface, Until the formed layer of the sulfur-containing melamine-formaldehyde resin mixture has a film quality of 5% of the total mass of the final product environmentally friendly composite coated slow release urea, the water is removed by drying. Subsequently, about 150 熔融 of molten sulfur is sprayed on the surface of the sulfur-containing melamine-formic acid tree's lipid mixture film layer until the quality of the formed sulfur film layer reaches 6% of the total mass of the final product environmentally friendly composite coated slow release urea. Then, a sulphur-containing melamine-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the sulfur film layer (melamine-formaldehyde resin prepolymer is prepared by reacting melamine with formaldehyde in a molar ratio of 1:3, and melamine: melamine The mass ratio of the waking resin prepolymer is 7:3) until the film quality of the layer of the sulfur-containing melamine-formaldehyde resin mixture formed reaches 3% of the total mass of the final product environmentally friendly composite coated slow release urea. Finally, a melamine-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the sulfur-containing melamine-formaldehyde resin mixture film layer (melamine-formaldehyde resin prepolymer is prepared by reacting melamine with a molar ratio of melamine of formaldehyde: 1:1). Until the formation of the layer of melamine-formaldehyde resin film layer quality reached 1% of the total quality of the final product environmentally friendly composite coated slow release urea. The water is removed from the film layer by drying, and the melamine-formaldehyde resin in the film layer is sufficiently cured to obtain an environmentally friendly composite coated type slow-release urea. The release period of the prepared environmentally-friendly composite coated slow release urea was 146 days.

 Example 8

 The granular industrial urea having a particle diameter of 2.0 to 4.0 mm is introduced into the fluidized bed coating device, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 90 °C. The molten sulfur at about 150 °C is slowly sprayed on the surface of the urea until the quality of the formed sulfur film reaches 9% of the total mass of the final product environmentally friendly composite coated slow release urea. Then, a sulfur-containing urea-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the sulfur film layer. The urea-formaldehyde resin prepolymer is prepared by reacting urea with formaldehyde in a molar ratio of 1:1.3, and sulfur: the quality of the urea-formaldehyde resin prepolymer. The ratio is 7:3) until the film quality of the formed sulfur-containing urea-formaldehyde resin mixture reaches 5% of the total mass of the final product environmentally friendly composite coated slow release urea. Finally, a urea-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the thiourea-containing resin mixture film layer (the urea-formaldehyde resin prepolymer is prepared by reacting urea with formaldehyde in a molar ratio of 1:1.8) until the urea-formaldehyde resin film is formed. The layer quality reaches 1.5% of the total quality of the finished product environmentally friendly composite coated slow release urea. Drying removes the water in the film layer and cures the urea-formaldehyde resin in the film layer sufficiently, that is, the environmentally friendly composite film-type slow-release urea is obtained. The release period of the environmentally friendly composite coated slow release urea was 105 days.

 Example 9

The granular industrial urea having a particle diameter of 2.0 to 4.0 mm is introduced into the fluidized bed coating device, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 70 °C. Tung oil and about 150 熔融 of molten sulfur were sprayed from different nozzles simultaneously to the surface of granular urea. By controlling their spray flow ratio, the average mass fraction of sulfur in the formed sulfur-containing tung oil resin mixture film layer was 70%. Spraying until the formation of the layer containing sulphur The film quality of the oleoresin mixture reaches 5% of the total mass of the final product environmentally friendly composite coated slow release urea. Then, stop spraying the tung oil, and continue to spray about 150 熔融 of molten sulfur on the surface of the sulfur-containing tung oil resin mixture film layer until the quality of the formed sulfur film layer reaches 8% of the total mass of the final product environmentally friendly composite coated type slow-release urea. Then, a benzene solution of a polyethylene wax having a molecular weight of 1500 is sprayed on the surface of the sulfur film layer until the quality of the formed polyethylene wax film layer reaches 1.5% of the total mass of the final product environmentally friendly composite coated slow release urea, and the benzene is sufficiently dried to remove benzene. . Finally, slowly spray sulphur-containing tung oil on the surface of the polyethylene wax film (containing 0.4% of the tung oil quality, sulphur: tung oil mass ratio is 1:1) until the formed sulfur-containing tung oil resin mixture film layer The quality reaches 4% of the total quality of the finished product environmentally friendly composite coated slow release urea. The tung oil resin in the film layer is sufficiently cured to obtain an environmentally friendly composite film type slow release urea. The release period of the prepared environmentally-friendly composite coated slow release urea was 203 days.

 Example 10

 Granular industrial urea having a particle size of 2.0 to 4.0 mm is introduced into the fluidized bed coating apparatus, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 75 °C. A sulphur-containing melamine-formaldehyde resin prepolymer aqueous solution (melamine-formaldehyde resin prepolymer is prepared by reacting melamine with formaldehyde in a molar ratio of 1:3.2, and sulfur: melamine-formaldehyde resin prepolymer) 7: 3) Sprayed on the urea surface until the formed layer of the sulfur-containing melamine-formic acid resin mixture has a film quality of 4% of the total mass of the final product environmentally friendly composite coated slow release urea, and the water is removed by drying. Subsequently, the surface of the sulfur-containing melamine-formaldehyde resin mixture film layer is slowly sprayed with molten sulfur at a temperature of about 150 ° C until the quality of the formed sulfur film layer reaches 6% of the total mass of the final product environmentally friendly composite coated slow release urea. Then, the temperature of the granular urea in the fluidized bed is lowered to 60 ° C, and the paraffin wax (melting point 75 ° C) at a temperature of 90 ° C is sprayed on the surface of the sulfur film layer until the quality of the formed paraffin film layer reaches the final product environmentally friendly compound. 2% of the total mass of the coated slow release urea. Finally, tung oil (containing a drier of 0.4% tung oil) was sprayed on the surface of the paraffin layer until the quality of the tung oil resin film reached 2% of the total mass of the final product-encapsulated composite coated slow-release urea. The melamine-carboxylic acid resin and the tung oil resin in the film layer are sufficiently cured to obtain an environmentally-friendly composite film-type slow-release urea. The release period of the environmentally friendly composite coated slow release urea was 197 days.

 Example 11

The granular industrial urea having a particle diameter of 2.0 to 4.0 mm is introduced into the fluidized bed coating device, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 75 °C. A sulphur-containing melamine-formaldehyde resin prepolymer aqueous solution (melamine-formaldehyde resin prepolymer is prepared by reacting melamine with formaldehyde in a molar ratio of 1:3.2, and sulfur: melamine-formaldehyde resin prepolymer) 7: 3) Sprayed on the urea surface until the formed layer of the sulfur-containing melamine-formaldehyde resin mixture reaches 4% of the total mass of the final product environmentally friendly composite coated slow release urea, and the water is removed by drying. Subsequently, the surface of the film layer of the sulfur-containing melamine-formaldehyde resin mixture is slowly sprayed with molten sulfur at a temperature of about 150 ° C until the quality of the formed sulfur film layer reaches the final. 6% of the total quality of the finished environmentally friendly composite coated slow release urea. Then, the temperature of the granular urea in the fluidized bed is lowered to 65 ° C, and the mixture of paraffin and rosin having a temperature of 95 喷涂 is sprayed (the mixture has a melting point of 80 ° C, and the paraffin: rosin mass ratio is 2:1). The melt is melted on the surface of the sulfur film layer. Until the formation of the paraffin and rosin mixture film quality reaches 2% of the total quality of the final product environmentally friendly composite coated slow release urea. Finally, the surface of the paraffin and rosin mixture film was sprayed with tung oil (containing 0.4% of tung oil quality drier) until the quality of the tung oil resin film layer reached 2% of the total quality of the final product environmentally friendly composite coated slow release urea. The trimeric guanamine-formaldehyde resin and the tung oil resin in the film layer are fully cured, that is, the environmentally friendly composite coated type sustained-release urea is obtained. The release period of the prepared environmentally-friendly composite coated slow release urea was 158 days.

 Example 12

 The granular industrial urea having a particle diameter of 2.0 to 4.0 mm was placed in a drum coating apparatus controlled at a temperature of 75 ° C, and the rotating drum (rotation speed of 40 r/min) was caused to flow the granular urea in the drum. Spraying butyl rubber (grade BR9175) benzene solution on the surface of granular urea until the quality of the formed butadiene rubber film reaches 1% of the total quality of the final product environmentally friendly composite coated slow release urea. The solvent benzene was removed. Then, 150 ° C molten sulfur was slowly sprayed on the surface of the butadiene rubber raw rubber film layer until the quality of the formed sulfur film layer reached 8% of the total mass of the final product environmentally friendly composite coated type slow release urea. Then, a sulfur-containing polyvinyl formal resin (polyvinyl alcohol grade 1799, 85% acetal) solution is sprayed on the surface of the sulfur film layer (the solvent is an ethanol-toluene mixed solvent, sulfur: polyvinyl alcohol The mass ratio of the formaldehyde resin is 7:3) until the film quality of the formed sulfur-containing polyvinyl formal resin mixture reaches 7% of the total mass of the final product environmentally friendly composite coated slow release urea. The solvent is sufficiently dried to completely cure the polyvinyl acetal resin, thereby obtaining an environmentally friendly composite coated slow release urea. The release period of the environmentally friendly composite coated slow release urea was 167 days.

 Example 13

 The granular industrial urea having a particle diameter of 2.0 to 4.0 mm is introduced into the fluidized bed coating device, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 70 °C. About 150 熔融 of molten sulfur is slowly sprayed on the surface of the urea until the quality of the formed sulfur film reaches 9% of the total mass of the final product environmentally friendly composite coated slow release urea. Then, a styrene-butadiene-styrene block copolymer (SBS, grade raton D1101) cyclohexanide solution is sprayed on the surface of the sulfur film layer until the formed styrene-butadiene-styrene block copolymer The film quality reaches 1% of the total mass of the final product environmentally friendly composite coated slow release urea, and the solvent is sufficiently dried. Then, a nitrocellulose solution (the solvent is a mixed solvent of ethanol, acetone and amyl acetate) is sprayed on the surface of the styrene-butadiene-styrene block copolymer film layer until the formed nitrocellulose film layer The quality reaches 3% of the total quality of the final finished environmentally friendly composite coated slow release urea. The solvent in the film layer is removed by drying to obtain an environmentally friendly composite coated slow release urea. The release period of the environmentally friendly composite coated slow release urea was 157 days.

 Example 14

Adding granular industrial urea with a particle size of 2.0~4.0mm into the fluidized bed coating equipment, and placing the granular urea in In the boiling state, the temperature of the granular urea in the fluidized bed is maintained at 90 °C. A sulphur-containing melamine-formaldehyde resin prepolymer aqueous solution (melamine-formaldehyde resin prepolymer is prepared by reacting melamine:melamine with a formaldehyde molar ratio of 1:2.7, and sulfur: melamine-formaldehyde resin prepolymer) Sprayed on the urea surface for 1:1) until the formed layer of the sulfur-containing melamine-formaldehyde resin mixture reaches 2% of the total mass of the final product environmentally friendly composite coated slow-release urea, and the water is removed by drying. Then, the surface of the sulfur-containing melamine-formaldehyde resin mixture film layer is slowly sprayed with molten sulfur at a temperature of about 150 ° C until the quality of the formed sulfur film layer reaches 10% of the total mass of the final product environmentally friendly composite coated slow release urea. Finally, a sulphur-containing melamine-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the sulfur film layer (melamine-formaldehyde resin prepolymer is prepared by reacting melamine with formaldehyde in a molar ratio of 1:3, and melamine: melamine The mass ratio of the formaldehyde resin prepolymer is 2:3) until the film quality of the layer of the sulfur-containing melamine-formaldehyde resin mixture formed reaches 6% of the total mass of the final product environmentally friendly composite coated slow release urea. The water is removed from the film layer by drying, and the melamine-formaldehyde resin in the film layer is sufficiently cured to obtain an environmentally friendly composite coated type slow-release urea. The release period of the prepared environmentally-friendly composite coated slow release urea was 131 days.

 Example 15

 The granular industrial urea with a particle size of 2.0~4.0mm is added to the fluidized bed coating equipment, and the granular urea is in a boiling state, and the granular urea temperature in the fluidized bed is maintained at 90 Ό. Spraying a sulfur-containing urea-formaldehyde resin prepolymer aqueous solution on the surface of granular urea (urea resin prepolymer is prepared by reacting urea with formaldehyde in a molar ratio of 1:2, and formaldehyde: the mass ratio of sulfur: urea-formaldehyde resin prepolymer is 3 2), until the formed layer of the thiourea-containing resin mixture film layer reaches 6% of the total mass of the final product environmentally friendly composite coated type slow-release urea, and the water is removed by drying. Then, molten sulfur at 150 ° C is slowly sprayed onto the surface of the film layer containing the thiourea resin mixture until the quality of the sulfur film layer formed reaches 10% of the total mass of the final product environmentally friendly composite coated slow release urea. Then, a sulfur-containing urea-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the sulfur film layer (the urea-formaldehyde resin prepolymer is prepared by reacting urea with a formaldehyde molar ratio of 1:1.5 and formaldehyde, and sulfur: urea-formaldehyde resin prepolymer) The mass ratio is 1:3) until the film quality of the layer containing the thiourea resin mixture is 2% of the total mass of the final product environmentally friendly composite coated slow release urea. The water is removed from the film layer, and the urea-formaldehyde resin in the film layer is sufficiently cured to obtain an environmentally-friendly composite film-type slow-release urea. The release period of the environmentally friendly composite coated slow release urea was 115 days.

 Example 16

The granular industrial urea having a particle diameter of 2.0 to 4.0 mm is introduced into the fluidized bed coating device, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 80 °C. A melamine-formaldehyde resin prepolymer aqueous solution (melamine-formaldehyde resin prepolymer is prepared by reacting melamine: melamine with a formaldehyde molar ratio of 1:3) and about 150 Å of molten sulfur from two different nozzles simultaneously The surface of the granular urea is slowly sprayed, and the sulfur content in the formed sulfur-containing melamine-formaldehyde resin mixture layer is controlled by controlling the spray flow ratio thereof. The average mass fraction of the sulfonate is 70% until the formed film layer of the sulfur-containing melamine-formaldehyde resin mixture reaches 3% of the total mass of the final product environmentally friendly composite coated slow release urea, and the water is removed by drying. Then, stop spraying the melamine-formaldehyde resin prepolymer aqueous solution, and continue to spray the molten sulfur at a temperature of about 150 ° C on the surface of the sulfur-containing melamine-formaldehyde resin mixture film layer until the quality of the formed sulfur film layer reaches the final product environmentally friendly composite coating type. 3.5% of the total mass of slow release urea. Finally, a sulphur-containing melamine-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the sulfur film layer (melamine-formaldehyde resin prepolymer is prepared by reacting melamine with formaldehyde in a molar ratio of 1:3, and melamine: melamine The mass ratio of the formaldehyde resin prepolymer is 1:1) until the film quality of the layer of the sulfur-containing triazide-formaldehyde resin mixture formed reaches 2% of the total mass of the final product environmentally friendly composite coated slow release urea. The melamine-formaldehyde resin in the film layer is sufficiently dried by sufficiently drying to remove water in the film layer, thereby obtaining an environmentally friendly composite coated type slow-release urea. The release period of the environmentally friendly composite coated slow release urea prepared was 56 days.

 Example 17

 Granular industrial urea having a particle size of 2.0 to 4.0 mm is introduced into the fluidized bed coating apparatus, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 90 °C. About 150 熔融 of molten sulfur is slowly sprayed on the surface of the urea until the quality of the sulfur film reaches 10% of the total mass of the final product environmentally friendly composite coated slow release urea. Then, a sulphur-containing melamine-formaldehyde resin prepolymer aqueous solution is sprayed on the sulfur film layer (melamine-formaldehyde resin prepolymer is prepared by reacting melamine with a formaldehyde molar ratio of 1:3, and melamine: melamine-formaldehyde The mass ratio of the resin prepolymer is 3: 2) until the film quality of the formed sulfur-containing melamine-formaldehyde resin mixture reaches 4% of the total mass of the final product environmentally friendly composite coated slow release urea. The water is removed from the film layer, and the melamine-formaldehyde resin in the film layer is sufficiently cured to obtain an environmentally-friendly composite film-type slow-release urea. The release period of the environmentally friendly composite coated slow release urea was 75 days.

 Example 18

The granular industrial urea with a particle size of 2.0~4.0mm is added to the fluidized bed coating equipment, and the granular urea is in a boiling state, and the granular urea temperature in the fluidized bed is maintained at 70T:. A sulphur-containing melamine-formaldehyde resin prepolymer aqueous solution (melamine-formaldehyde resin prepolymer is prepared by reacting melamine: melamine having a molar ratio of 1:3 with formaldehyde, sulfur: melamine-formaldehyde resin prepolymer mass ratio 7: 3) Sprayed on the urea surface until the formed layer of the sulfur-containing melamine-formaldehyde resin mixture reaches 4% of the total mass of the final product environmentally friendly composite coated slow release urea, and the water is removed by drying. Subsequently, the surface of the sulfur-containing melamine-formaldehyde resin mixture film layer is slowly sprayed with molten sulfur at a temperature of about 150 ° C until the quality of the formed sulfur film layer reaches 6% of the total mass of the final product environmentally friendly composite coated slow release urea. Then, a benzene solution of acrylonitrile-butadiene-styrene copolymer (Lanzhou Petrochemical Company, brand ABS-301) is sprayed on the surface of the sulfur film layer until the formed acrylonitrile-butadiene-styrene copolymer film The layer quality reaches the total quality of the final product environmentally friendly composite coated slow release urea 1%. Finally, the surface of the acrylonitrile-butadiene-styrene copolymer film was sprayed with tung oil (containing 0.4% dregs of tung oil) until the quality of the tung oil resin film reached the final product environmentally friendly composite film type sustained release. 2% of the total mass of urea. The melamine-formaldehyde resin and the tung oil resin in the film layer are fully cured, that is, the environmentally-friendly composite coated type slow-release urea is obtained. The release period of the environmentally friendly composite coated slow release urea was 165 days.

 Example 19

 The granular industrial urea with a particle size of 2.0 to 4.0 min is added to the fluidized bed coating equipment, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 90 °C. The melamine-formaldehyde resin prepolymer aqueous solution (melamine-formaldehyde resin prepolymer is prepared by reacting melamine:melamine with a formaldehyde molar ratio of 1:3.5 and formaldehyde) is slowly sprayed on the surface of the granular urea until the layer of melamine is formed. The quality of the formaldehyde resin film layer reaches 1.5% of the total quality of the final product environmentally friendly composite coated slow release urea. Then, the melamine-formaldehyde resin prepolymer aqueous solution is sprayed slowly from the two different nozzles to the surface of the melamine-formaldehyde resin film layer (melamine-formaldehyde resin prepolymer is melamine: melamine with a molar ratio of 1:2.5) The formaldehyde produced by the formaldehyde reaction) and the molten sulfur at about 150 ° C, by controlling the spray flow ratio thereof, the average mass fraction of sulfur in the formed sulfur-containing melamine-formaldehyde resin mixture layer is 85%, and spraying until the layer is formed. The film quality of the sulfur-containing melamine-formaldehyde resin mixture reaches 4% of the total mass of the final product environmentally friendly composite coated slow release urea, and the water is removed by drying. Subsequently, the spraying of the melamine-formaldehyde resin prepolymer aqueous solution is stopped, and the molten sulfur is continuously sprayed at about 150 ° C until the quality of the formed sulfur film layer reaches 6% of the total mass of the final product environmentally friendly composite coated slow release urea. Then, a sulphur-containing melamine-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the sulfur film layer (melamine-formaldehyde resin prepolymer is prepared by reacting melamine: melamine having a molar ratio of 1:3 with formaldehyde, sulfur: melamine one The mass ratio of the formaldehyde resin prepolymer is 7:3) until the film quality of the layer of the sulfur-containing melamine-formaldehyde resin mixture formed reaches 3% of the total mass of the final product environmentally friendly composite coated slow release urea. Finally, a melamine-formaldehyde resin prepolymer aqueous solution is slowly sprayed on the surface of the sulfur-containing melamine-formaldehyde resin mixture film layer (melamine-formaldehyde resin prepolymer is prepared by reacting melamine with a formaldehyde molar ratio of 1:2 and formaldehyde). ), until the formation of the layer of melamine-formic acid resin film layer quality reached 1.5% of the total quality of the final product environmentally friendly composite coated slow release urea. The water is removed from the film layer by drying, and the melamine-formaldehyde resin in the film layer is sufficiently cured to obtain an environmentally friendly composite coated type slow-release urea. The release period of the environmentally friendly composite coated slow release urea was 156 days.

 Example 20

8 x 3 ^ 1 of flaky urea was added to the fluidized bed coating apparatus, and the flaky urea was placed in a boiling state, and the temperature of the flaky urea in the fluidized bed was maintained at 90 ° C. A melamine-formaldehyde resin prepolymer aqueous solution (melamine-formaldehyde resin prepolymer is prepared by reacting melamine with a formaldehyde molar ratio of 1:2.6 and melamine) and a sulphur sulphur at a temperature of about 150 ° C are respectively different from the two groups. The nozzle is slowly sprayed onto the surface of the flaky urea at the same time. Their spraying flow ratio is such that the average mass fraction of sulfur in the formed sulfur-containing melamine-formaldehyde resin mixture layer is 70%, and the quality of the layer of the sulfur-containing melamine-formaldehyde resin mixture formed until the formation reaches the final finished environmentally friendly composite package. 5% of the total mass of the membrane type slow-release urea, drying to remove water in the film layer. Then, stop spraying the melamine-formaldehyde resin prepolymer aqueous solution, and continue to spray 150 ° C molten sulfur on the surface of the sulfur-containing melamine-formaldehyde resin mixture film layer until the quality of the formed sulfur film layer reaches the final product environmentally friendly composite coating type. Release 15% of the total quality of urea. Then, a sulphur-containing melamine-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the sulfur film layer (melamine-formaldehyde resin prepolymer is prepared by reacting melamine with formaldehyde in a molar ratio of 1:3, and melamine: melamine The mass ratio of the formaldehyde resin prepolymer is 1:1) until the film quality of the layer of the sulfur-containing melamine-formaldehyde resin mixture formed reaches 5% of the total mass of the final product environmentally friendly composite coated slow release urea. The water is removed from the film layer by drying, and the melamine-formaldehyde resin in the film layer is sufficiently cured to obtain an environmentally friendly composite coated type slow-release urea. The release period of the prepared environmentally-friendly composite coated slow release urea was 245 days.

 Example 21

 The granular industrial urea with a particle size of 2.0 to 4.0 mm was placed in a drum coating device with a temperature control of 65 ° C, and the rotating drum (rotation speed 40 r / min) was used to flow the granular urea in the drum. Spraying a solution of polyvinyl formal resin (polyvinyl alcohol grade 1799, acetal degree 55%) on the surface of granular urea until the formed polyvinyl formal resin film layer The quality reaches 3% of the total mass of the final product environmentally friendly composite coated slow release urea, and the solvent is sufficiently dried. Then, 150 ° C of molten sulfur is slowly sprayed on the surface of the polyvinyl formal resin film layer until the quality of the formed sulfur film layer reaches 8% of the total mass of the final product environmentally friendly composite coated type slow release urea. Then, on the surface of the sulfur film layer, a polyvinyl alcohol shrinking resin (polyvinyl alcohol grade 1799, acetal degree 90%) ethanol solution is sprayed until the quality of the formed polyvinyl butyral resin film layer reaches the final. 4% of the total quality of the finished environmentally friendly composite coated slow release urea. The solvent is sufficiently dried to completely solidify the polyvinyl acetal resin, thereby obtaining an environmentally friendly composite coated slow release urea. The release period of the environmentally friendly composite coated slow release urea prepared was 106 days.

 Example 22

The granular industrial urea with a particle size of 2.0~4.0imn is added to the fluidized bed coating equipment, and the granular urea is in a boiling state, and the granular urea temperature in the fluidized bed is maintained at 90 °C. The aqueous solution of the melamine-modified urea-formaldehyde resin prepolymer is slowly sprayed on the surface of the granular urea until the quality of the layer of the melamine-modified urea-formaldehyde resin layer reaches 2% of the total mass of the final product environmentally friendly composite coated slow-release urea. Then, from the two sets of different nozzles, the polyvinyl alcohol-modified urea-formaldehyde resin prepolymer aqueous solution and 150 Å of molten sulfur are sprayed on the surface of the melamine-modified urea-formaldehyde resin film layer simultaneously, and the spray flow ratio is controlled by controlling the spray flow ratio thereof. The average mass fraction of sulfur in the film layer of the sulfur-containing polyvinyl alcohol modified urea-formaldehyde resin mixture is 75%, and the quality of the film layer of the sulfur-containing polyvinyl alcohol-modified urea-formaldehyde resin mixture formed until the formation of the layer is the final product environmentally friendly composite film type Release 3% of the total mass of urea, dry to remove water in the film. With After that, the spraying of the polyvinyl alcohol-modified urea-formaldehyde resin prepolymer aqueous solution is stopped, and the molten sulfur is continuously sprayed for about 150 C until the quality of the formed sulfur film layer reaches 7% of the total mass of the final product environmentally friendly composite coated slow-release urea. Then, from the two sets of different nozzles, the ethanol-modified melamine-formaldehyde resin prepolymer aqueous solution and the molten sulfur at about 150 °C are sprayed slowly onto the surface of the sulfur film layer, and the sulfur content formed is controlled by controlling the spray flow ratio thereof. The average mass fraction of sulfur in the membrane of the ethanol-modified melamine-formaldehyde resin mixture is 65%, and the quality of the film layer of the melamine-modified melamine-formaldehyde resin mixture is reached until the final product of the environmentally friendly composite coating type slow-release urea is formed. 2% of the total mass. Finally, the melamine-formaldehyde resin prepolymer aqueous solution is slowly sprayed on the surface of the thiol-modified melamine-formaldehyde resin mixture film layer (melamine-formaldehyde resin prepolymer is melamine: melamine and formaldehyde with a molar ratio of 1:1.5) The reaction is prepared) until the quality of the layer of the melamine-formaldehyde resin layer formed reaches 2% of the total mass of the final product environmentally friendly composite coated slow release urea. The water in the film layer is removed by drying, and the modified urea-formaldehyde resin and the (modified) melamine-formaldehyde resin in the film layer are sufficiently cured to obtain an environmentally-friendly composite film-type slow-release urea. The release period of the environmentally friendly composite coated slow release urea prepared was 160 days.

 Example 23

 The granular industrial urea having a particle diameter of 2.0 to 4.0 mm is introduced into the fluidized bed coating device, and the granular urea is in a boiling state, and the temperature of the granular urea in the fluidized bed is maintained at 90 °C. The n-butanol-modified urethane resin prepolymer aqueous solution and the molten sulfur at about 150 °C are simultaneously sprayed from the two different nozzles to the urea surface, and the formed sulfur-containing n-butanol is changed by controlling the spray flow ratio thereof. The average mass fraction of sulfur in the film layer of the urea-formaldehyde resin mixture is 80%, and the film quality of the layer of sulfur-containing n-butanol-modified urea-formaldehyde resin mixture is up to 4, which is the total quality of the final product environmentally friendly composite coated type slow-release urea. %, dried to remove water in the film layer. Subsequently, the surface of the sulfur-containing n-butanol-modified urea-formaldehyde resin mixture film layer was slowly sprayed with molten sulfur at a temperature of about 150 ° C until the quality of the formed sulfur film layer reached 6% of the total mass of the final product environmentally friendly composite coated slow release urea. Then, a sulfur-containing ethanol-polyvinyl alcohol-modified melamine-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the sulfur film layer (the mass ratio of sulfur:ethanol-polyvinyl alcohol modified melamine-formaldehyde resin prepolymer is 7: 3), until the formation of the layer of sulfur-containing ethanol-polyvinyl alcohol modified melamine-formaldehyde resin mixture film layer quality reached 4% of the total quality of the final product environmentally friendly composite coated slow release urea. Finally, a urea-formaldehyde resin prepolymer aqueous solution is sprayed on the surface of the thiol-polyvinyl alcohol-modified melamine-formaldehyde resin mixture film layer (urea resin prepolymer is urea: formaldehyde molar ratio of 1:1.05 urea and formaldehyde reaction Prepared) until the quality of the layer of urea-formaldehyde resin film formed reaches 1% of the total mass of the final product environmentally friendly composite coated slow release urea. The water in the film layer is removed by drying, and the (modified) urea-formaldehyde resin and the modified melamine-formaldehyde resin in the film layer are sufficiently cured to obtain an environmentally friendly composite coated type slow-release urea. The release period of the environmentally friendly composite coated slow release urea was 142 days.

In the above embodiment, the urea-formaldehyde resin prepolymer aqueous solution is prepared by reacting urea with formaldehyde, and the molar ratio of urea to formaldehyde may be in the range of 1: (1~3), which is generally known by those skilled in the art, usually 1 : ( 1~2) Preferably, a 2% ammonium chloride curing agent having a urea resin resin prepolymer mass of 2% is added before the film coating. The melamine modified urea-formaldehyde resin prepolymer aqueous solution is prepared by the reaction of urea, melamine and formaldehyde. The urea:melamine:formaldehyde molar ratio is 1:1:4, and the melamine modified urea-formaldehyde resin prepolymer is added with 2% of the chlorine before the coating. Ammonium curing agent. The aqueous solution of polyvinyl alcohol modified urea-formaldehyde resin prepolymer is prepared by reacting urea, formaldehyde and polyvinyl alcohol. The ratio of urea:formaldehyde:polyvinyl alcohol (1799) is 100:89:3, and polyvinyl alcohol is added before coating. The urea-formaldehyde resin prepolymer has a 2% ammonium chloride curing agent. The n-butanol modified urea-formaldehyde resin prepolymer aqueous solution is prepared by the reaction of urea, formaldehyde and n-butanol. The urea:formaldehyde: n-butanol molar ratio is 1: 1.37: 1, and the n-butanol modified urea-formaldehyde resin is added before the film coating. Prepolymer mass 2% ammonium chloride curing agent.

 In the above embodiment, the aqueous solution of the melamine-formaldehyde resin prepolymer is prepared by reacting melamine with formaldehyde, and the molar ratio of melamine to formaldehyde may be in the range of 1: (1~4), which is generally known to those skilled in the art, usually It is preferred to use 1: (1.5~3.5), and add 2% ammonium chloride or triethanolammonium curing agent of melamine-formaldehyde resin prepolymer before coating. The ethanol modified melamine-formaldehyde resin prepolymer aqueous solution is prepared by the reaction of trimeric amine, formaldehyde and ethanol. The melamine:formaldehyde:ethanol molar ratio is 1:2.5:2, and the ethanol modified melamine-formaldehyde resin is pre-coated before coating. 2% ammonium chloride curing agent. The ethanol-polyvinyl alcohol modified melamine-formaldehyde resin prepolymer aqueous solution is prepared by the reaction of melamine, formaldehyde, ethanol and polyvinyl alcohol, and the melamine:formaldehyde:ethanol:polyvinyl alcohol (1788) mass ratio is 100:67:12: 2.5, before the film coating, add ethanol-polyvinyl alcohol modified melamine-formaldehyde resin prepolymer mass 2% ammonium chloride curing agent.

 As is known to those skilled in the art, the modified urea-formaldehyde resin and the modified melamine-formaldehyde resin are respectively a urea-formaldehyde resin and a melamine-formaldehyde resin, and the modified urea-formaldehyde resin and the modified melamine used in the above embodiments are The formaldehyde resin is only a representative of the modified urea 'aldehyde resin and the modified melamine-formaldehyde resin respectively. The preparation formula of the modified urethane resin and the modified melamine-formaldehyde resin can only be used as a formula, and The scope of the invention is not limited. The melamine resin in the amino resin may be prepared by using glyoxal and furfural instead of formaldehyde in addition to the above (modified) melamine-formaldehyde resin, and the related embodiments are not listed in the detailed description of the present specification, but such a class Melamine resins are still within the scope of the invention.

 In the above examples, the tung oil used for the tanning is a commercially available tung oil from Qiubei, Yunnan, having an acid value of 5.0 mgKOH/g.

Claims

Claim  1. An environmentally friendly composite coated slow release fertilizer consisting of a fertilizer core [1] and a coating film on the outer side of the fertilizer core, characterized in that: the envelope comprises (a) a sulfur film layer [2], (b) sulfur content Degradable polymer mixture film layer [3] and/or degradable polymer film layer [4], with or without (c) high barrier organic film layer [5]; wherein the sulfur film layer is in the entire envelope Layer or intermediate layer. The environmentally-friendly composite coated slow-release fertilizer according to claim 1, wherein the sulfur-containing degradable polymer mixture has an average mass fraction of sulfur of 20% to 90%.  The environmentally friendly composite coated slow release fertilizer according to claim 1, wherein the degradable polymer is an acetal resin of an amino resin, a polyvinyl alcohol and a copolymer thereof, an unsaturated oleoresin, and a natural polymer. One or more of its derivatives; wherein the natural polymer and its derivative are one of nitrocellulose, shellac, cellulose acetate, crosslinked starch, chitin derivative, lignin derivative Kind or more.  The environmentally-friendly composite coated slow-release fertilizer according to claim 1, wherein the high-barrier organic film layer is a non-polar organic film layer, and the non-polar organic film layer material is a non-polar low-molecular-weight organic material. And / or non-polar polymers. The environmentally friendly composite coated slow release fertilizer according to claim 4, wherein the non-polar organic film layer is in close contact with the sulfur film layer.  The environmentally-friendly composite coated slow release fertilizer according to claim 4, wherein the non-polar low molecular weight organic substance is a wax having a melting point of ≥ 40 ° C, a melting point or a softening point of ≥ 40 ° C and a molecular weight of ≤ 2000. Polyolefin or polystyrene and one or more of the petroleum resins having a softening point of ≥ 4 (TC).  The environmentally friendly composite coated slow release fertilizer according to claim 4, wherein the non-polar polymer is polyolefin, polystyrene, butadiene rubber, natural rubber, polyisoprene rubber, and butyl. One of benzene rubber, butyl rubber, ethylene propylene rubber and ethylene propylene diene monomer, styrene-butadiene-styrene block copolymer and styrene-isoprene-styrene block copolymer or More than one.  The environmentally friendly composite coated slow release fertilizer according to any one of claims 1 to 7, wherein the high barrier organic film layer contains a sustained release modifier.  The environmentally-friendly composite coated slow-release fertilizer according to any one of claims 1 to 7, wherein the total thickness of the coating is 10 to 180/m, and the average thickness of the sulfur film is 1 to 100. m, the total average thickness of both the degradable polymer film layer and the sulfur-containing degradable polymer mixture film layer is 5 to 180 m, and the total average thickness of the high-barrier organic film layer is 0 to 15 m, and the sulfur film layer is outward The average thickness of the film layer is not less than 3 m; the total average thickness of the film of the sulfur-containing degradable polymer mixture is 0 to 100 m, and the total average thickness of the degradable polymer film layer is 0 to 100 / m. The environmentally-friendly composite coated slow-release fertilizer according to claim 9, wherein: the total average thickness of the coating is 20 to 90 m, wherein the average thickness of the sulfur film is 8 to 60/m, which is degradable. The total average thickness of both the polymer film layer and the sulfur-containing degradable polymer mixture film layer is 8 to 50 / m, and the total average thickness of the high-barrier organic film layer is 0 to 10 / m, and the sulfur film is outwardly filmed. The average thickness of the layer is not less than 5 m; the total average thickness of the film of the sulfur-containing degradable polymer mixture is 8 to 50 / m, and the total average thickness of the degradable polymer film layer is 0 to 35 m.