Patent Publication Number: US-2022235210-A1

Title: Green environmentally friendly adhesive dipping liquid and method for production thereof

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     The present invention claims priority to Chinese patent application No. 201910607037.3 filed before the China Patent Office and entitled “Environment-friendly impregnation solution and preparation method therefor”, which is incorporated by reference herein in its entirety. 
     TECHNICAL FIELD 
     The invention relates to the technical field of preparation of impregnation solution, and in particular, to an environment-friendly impregnation solution without formaldehyde and resorcinol, and a method for preparing the same. 
     BACKGROUND ART 
     In recent years, with the rapid development of automobile manufacturing industry and transportation industry (especially expressway), the demand for radial tyres with superior performance has increased rapidly. The radial tyres mostly take fiber fabrics, such as Chinlon, Dacron, and Aramid as framework materials, and thus there is a need for effective adhesion between rubber and the fiber fabrics such as Chinlon. In order to improve the adhesion between fibers and rubber materials, a resorcinol-formaldehyde-latex (RLF) adhesive system was invented in 1935 through research, and it has been used ever since. It is the most effective and economic adhensive system for rubber adhension to fiber as proved by time. 
     With the rapid economic development, the demand for rubber products and rubber framework materials is increasing. At the same time, with the awareness of environmental protection and occupational health and safety, people are paying increasing attention to chemicals such as resorcinol, formaldehyde, and the like. Countries of the world have started to reduce or even eliminate the use of harmful chemicals from the aspects of laws, regulations, industry standards, and the like. 
     It has been recited in  Catalogue of State - encouraged Substitutes for Toxic and Harmful Raw Materials  ( Products ) (2016) issued by MITT and the like, that “the phenolic resin (RLF) impregnant” has been listed as the substitute in items 6 and 7 in (II) with the subtitle “the Substitutes for Organic Pollutants”. With the implementation of EU tyre labelling rules and other related laws and regulations on green tyres around the world, the greening progress of tyre raw materials has been rapidly promoted. At present, RFL (resorcinol, formaldehyde, and latex) is widely used in the adhesive system of rubber and rubber skeleton materials, and the contents of resorcinol and formaldehyde therein have been clearly limited. In addition, raw materials such as resorcinol, ammonia water in the RFL system have a stink and pungent odor, making the air of preparation workshop unpleasant; and the formaldehyde solution, as a dangerous chemical, must meet higher safety management requirements in storage and use, which improves the explosion-proof grade of the impregnation solution preparation workshop. 
     In various literature documents and patents, it has been reported that the impregnation solution without formaldehyde and resorcinol was used to improve the adhesive force and other application performance indicators of organic fiber materials after impregnation. 
     An impregnant currently used by Goodyear Company was formed by copolymerization of one or two acrylic monomers and a small amount of styrene to form acrylic resin, which was then mixed with latex to prepare the impregnant formula. When non-activated polyester fibers were used, the fibers need to be activated by epoxy compounds in a first bath and impregnated in the acrylic resin-latex system in a second bath, and the resultant performance of the framework material after impregnation is similar to that after impregnation in a traditional RFL system, and however, the overall technological process is complicated, the equipment investment is high, and the raw materials are all from specified suppliers, which is highly dependent on upstream products. 
     The formula, as currently claimed by a patent owned by Pirelli Tire Co., Ltd., contains at least rubber latex, epoxide, and polyamine with a molecular weight greater than 190 Dalton. In the structural elements, the adhesion between the framework material and the rubber material in these compositions is close to that of the traditional RFL system used in this industry. However, polyamine, one of the raw materials used in the formula, is demanding and high-cost, and the use thereof in the traditional preparation workshop does not meet the current environmental protection policy, and in the process of impregnation, hub sticking easily occurs, resulting in phased shutdown maintenance and other unfavorable factors, which are detrimental to continuous production. 
     The information disclosed in the Background section is only intended to enhance understanding of the general background of the invention and should not be taken as an acknowledgment or in any form implying that the information constitutes the prior art already known to those skilled in the art. 
     SUMMARY OF THE INVENTION 
     The invention aims to provide an environment-friendly impregnation solution and a method for preparing the same in order to solve the technical problems existing in the impregnation solutions described above. The impregnation solution of the invention does not contain toxic and harmful substances such as formaldehyde and resorcinol, and the preparation method thereof is simple, easy to operate, short in production cycle and has a high safety factor, thus ensuring that the impregnation solution preparation and impregnation process are safe and environment-friendly. 
     To solve the above problems, the technical solution provided by the invention is as follows: An environment-friendly impregnation solution, which comprises the following raw materials in percentage by weight: 1-15% of blocked isocyanate, 0.5-10% of special amino resin, 10-50% of rubber latex, 1-5% of auxiliaries, and the balance of water, wherein the sum of the weight percentage of each component is 100%; 
     the auxiliaries consist of Auxiliary a and Auxiliary b, with the mass ratio of 1:1-3. 
     In an embodiment of the invention, the environment-friendly impregnation solution described above comprises the following raw materials in percentage by weight: 1-5% of blocked isocyanate, 1.5-10% of special amino resin, 20-40% of rubber latex, 3-5% of auxiliaries, and the balance of water, wherein the sum of the weight percentage of each component is 100%; 
     the auxiliaries consist of Auxiliary a and Auxiliary b, with the mass ratio of 1:1-3. 
     With respect to the environment-friendly impregnation solution described above, the special amino resin is one or more of urea-formaldehyde resin, melamine-formaldehyde resin, benzoxazine resin, and polyamide polyamine epichlorohydrin. 
     With respect to the environment-friendly impregnation solution described above, the rubber latex is one or more of butadiene-vinylpyridine copylymer latex, butadiene latex, ethylene propylene diene monomer (EPDM), styrene-butadiene latex, natural latex, butyronitrile latex, carboxylic butadiene-vinylpyridine copylymer latex, carboxylic styrene-butadiene latex, and carboxylic butyronitrile latex. 
     With respect to the environment-friendly impregnation solution described above, the Auxiliary a is Tween 20, sodium diisobutyl naphthalene sulfonate, Tween 80, or fatty alcohol polyoxyethylene ether. 
     With respect to the environment-friendly impregnation solution described above, the Auxiliary b is a grinding aid for superfinely wet-grinding high-granularity kaolin and porcelain clay, aqueous calcium stearate emulsion, or sodium hexametaphosphate. 
     With respect to the environment-friendly impregnation solution described above, the impregnation solution has a solid content of 5-30%. 
     In addition, the invention provides a method for preparing the environment-friendly impregnation solution, which comprises the following steps: 
     a) firstly, weighing the respective raw materials in a ratio according to the formula of the environment-friendly impregnation solution described above; 
     b) adding the weighed blocked isocyanate and Auxiliary a into water and stirring uniformly to obtain Composition 1; 
     c) then adding Auxiliary b to the obtained Composition 1 and stirring uniformly to obtain Composition 2; 
     d) and adding special amino resin to the obtained Composition 2 and stirring uniformly, then grinding to obtain Composition 3; 
     e) adding rubber latex to the obtained Composition 3, and stirring uniformly to obtain the environment-friendly impregnation solution, followed by packaging. 
     With respect to the method for preparing the environment-friendly impregnation solution, the particle size distribution of solids in Composition 3 after grinding in step d) is between 1 and 50 μm. 
     Beneficial Effects 
     1. The impregnation solution of the invention functions by providing one or more forces between organic fiber materials and rubbers to make the organic fiber materials and the rubbers adhere to each other; the impregnation solution of the invention comprises blocked isocyanate, special amino resin, and the like as the main components, and has no toxic and harmful substances such as formaldehyde and resorcinol; the preparation method thereof is simple and easy to operate, short in production cycle, and has a high safety factor. Consequently, the impregnation solution preparation and impregnation processes are safe and green, without generation of waste materials, and are environment-friendly. 
     2. The impregnation solution of the invention is different from the existing RFL impregnation solution, and is stable in storage and transportation, thus filling a gap in the market. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       One or more examples are exemplified by the FIGURES in the accompanying drawings that correspond thereto and are not intended to be limiting of the embodiments. As used herein, the word “exemplary” means “serving as an example, embodiment, or illustrative”. Any embodiment described herein as “exemplary” is not necessarily to be construed as being superior to or better than other embodiments. 
         FIG. 1  is a schematic diagram of the process flow of the preparation method of the environment-friendly impregnation solution of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In order to make the purpose, technical solutions and advantages of the embodiments of the invention clearer, the technical solutions in the embodiments of the invention will be clearly and completely illustrated with reference to one or more embodiments and corresponding drawings. 
     Obviously, the described embodiments are some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of the present invention. Throughout the specification and claims, the term “comprising” or variations thereof, such as “including” or “containing” and the like, will be understood to include the stated components and not to exclude other elements or other components, unless expressly indicated otherwise. 
     These embodiments are not intended to limit the scope of protection. Unless otherwise stated, any embodiment herein is not necessarily to be construed as being superior to or better than other embodiments. 
     In addition, in order to better explain the present invention, a lot of specific details are given in the following embodiments. It will be understood by those skilled in the art that the present invention may be practiced without certain specific details. In some embodiments, methods, means, elements well known to those skilled in the art, experimental methods generally according to conventional conditions and according to the conditions described in the manual or according to the conditions suggested by the manufacturer are not described in detail so as to highlight the spirit of the present invention. The materials and reagents used are conventionally commercially available, unless otherwise specified. 
     In the following examples, the raw materials used were all commercial available, in which: 
     blocked isocyanate, with a viscosity of 200-500 mpa·s/25° C., a solid content of 50±1.5%, a density of 1.0±0.2 g/cm 3  (20° C.), and a particle size of ≤5 μm; 
     Bisphenol A/aniline benzoxazine resin, with a molecular weight of 466-800, a softening point of 50-90° C., and gel time (210° C., 1 g) of 100-400 seconds; 
     Phenol/MDA benzoxazine resin, with a molecular weight of 438-800, a softening point of 50-90° C., and gel time (210° C., 1 g) of 100-400 seconds; 
     Bisphenol F/aniline benzoxazine resin, with a molecular weight of 438-800, a softening point of 50-90° C., and gel time (210° C., 1 g) of 100-400 seconds; 
     Butadiene-vinylpyridine copylymer latex, with a viscosity of 20-45 mpa·s/25° C., a solid content of 39.5-41.5%, a density of 0.980-0.990 g/cm 3  (20° C.), and pH 10-12; 
     Carboxylic styrene-butadiene latex, with a viscosity of 4-350 mpa·s/25° C., a solid content of 48.0-54.0%, a density of 0.970-0.100 g/cm 3  (20° C.), and pH 7.0-9.0; 
     Styrene-butadiene latex, with a viscosity of 200-800 mpa·s/25° C., a solid content of 48.0-61.0%, a density of 0.960-0.980 g/cm 3  (20° C.), and pH 8.0-10.5; 
     Butadiene latex, with a viscosity of 10-50 mpa·s/25° C., a solid content of 48.0-54.0%, a density of 1.01-1.20 g/cm 3  (20° C.), and pH 12.0-14.0; 
     Butyronitrile latex, with a viscosity of 7-50 mpa·s/25° C., a solid content of 43.0-45.0%, and pH 7.0-8.0; 
     Carboxylic styrene-butadiene latex, with a viscosity of 4-350 mpa·s/25° C., a solid content of 48.0-54.0%, a density of 0.970-0.100 g/cm 3  (20° C.), and pH 7.0-9.0. 
     Example 1 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 150 kg blocked isocyanate, 5 kg benzoxazine resin, 100 kg butadiene-vinylpyridine copylymer latex, 15 kg Auxiliary a (fatty alcohol polyoxyethylene ether), 25 kg Auxiliary b (sodium hexametaphosphate), and 705 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 15.0%. 
     In this example, the benzoxazine resin was bisphenol A/aniline benzoxazine resin having the bisphenol A/aniline bicyclic structure. 
     Example 2 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 100 kg blocked isocyanate, 15 kg benzoxazine resin, 300 kg carboxylic styrene-butadiene latex, 15 kg Auxiliary a (fatty alcohol polyoxyethylene ether), 25 kg Auxiliary b (sodium hexametaphosphate), and 545 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 24%. 
     In this example, the benzoxazine resin was phenol/MDA benzoxazine resin having the phenol/MDA bicyclic structure. 
     Example 3 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 50 kg blocked isocyanate, 15 kg benzoxazine resin, 300 kg butadiene-vinylpyridine copylymer latex, 15 kg Auxiliary a (fatty alcohol polyoxyethylene ether), 25 kg Auxiliary b (sodium hexametaphosphate), and 595 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 18.0%. 
     In this example, the benzoxazine resin was bisphenol F/aniline benzoxazine resin having the bisphenol F/MDA bicyclic structure. 
     Example 4 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 50 kg blocked isocyanate, 60 kg benzoxazine resin, 500 kg carboxylic styrene-butadiene latex, 15 kg Auxiliary a (fatty alcohol polyoxyethylene ether), 25 kg Auxiliary b (sodium hexametaphosphate), and 350 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 35.5%. 
     In this example, the benzoxazine resin was bisphenol F/aniline benzoxazine resin having the bisphenol F/MDA bicyclic structure. 
     Example 5 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 10 kg blocked isocyanate, 100 kg benzoxazine resin, 300 kg carboxylic styrene-butadiene latex, 15 kg Auxiliary a (fatty alcohol polyoxyethylene ether), 25 kg Auxiliary b (sodium hexametaphosphate), and 550 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 30%. 
     In this example, the benzoxazine resin was bisphenol A/aniline benzoxazine resin having the bisphenol A/aniline bicyclic structure. 
     Example 6 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 150 kg blocked isocyanate, 5 kg benzoxazine resin, 100 kg EPDM, 15 kg Auxiliary a (fatty alcohol polyoxyethylene ether), 25 kg Auxiliary b (sodium hexametaphosphate), and 705 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 15.0%. 
     In this example, the benzoxazine resin was bisphenol A/aniline benzoxazine resin having the bisphenol A/aniline bicyclic structure. 
     Example 7 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 100 kg blocked isocyanate, 15 kg benzoxazine resin, 300 kg EPDM, 15 kg Auxiliary a (fatty alcohol polyoxyethylene ether), 25 kg Auxiliary b (sodium hexametaphosphate), and 545 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 24%. 
     In this example, the benzoxazine resin was bisphenol A/aniline benzoxazine resin having the bisphenol A/aniline bicyclic structure. 
     Example 8 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 50 kg blocked isocyanate, 15 kg benzoxazine resin, 300 kg EPDM, 15 kg Auxiliary a (fatty alcohol polyoxyethylene ether), 25 kg Auxiliary b (sodium hexametaphosphate), and 595 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 21%. 
     In this example, the benzoxazine resin was bisphenol A/aniline benzoxazine resin having the bisphenol A/aniline bicyclic structure. 
     Example 9 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 50 kg blocked isocyanate, 60 kg benzoxazine resin, 500 kg butadiene-vinylpyridine copylymer latex, 15 kg Auxiliary a (fatty alcohol polyoxyethylene ether), 25 kg Auxiliary b (sodium hexametaphosphate), and 350 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 31%. 
     In this example, the benzoxazine resin was phenol/MDA benzoxazine resin having the phenol/MDA bicyclic structure. 
     Example 10 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 10 kg blocked isocyanate, 100 kg benzoxazine resin, 300 kg styrene-butadiene latex, 15 kg Auxiliary a (fatty alcohol polyoxyethylene ether), 25 kg Auxiliary b (aqueous calcium stearate emulsion), and 550 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 30%. 
     In this example, the benzoxazine resin was bisphenol A/aniline benzoxazine resin having the bisphenol A/aniline bicyclic structure. 
     Example 11 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 150 kg blocked isocyanate, 5 kg benzoxazine resin, 100 kg butadiene latex, 15 kg Auxiliary a (Tween 20), 25 kg Auxiliary b (sodium hexametaphosphate), and 705 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 15.0%. 
     In this example, the benzoxazine resin was bisphenol A/aniline benzoxazine resin having the bisphenol A/aniline bicyclic structure. 
     Example 12 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 100 kg blocked isocyanate, 15 kg benzoxazine resin, 300 kg butadiene latex, 15 kg Auxiliary A (Tween 80), 25 kg Auxiliary B (sodium hexametaphosphate), and 545 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 24%. 
     In this example, the benzoxazine resin was phenol/MDA benzoxazine resin having the phenol/MDA bicyclic structure. 
     Example 13 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 50 kg blocked isocyanate, 15 kg benzoxazine resin, 300 kg butadiene-vinylpyridine copylymer latex, 15 kg Auxiliary a (sodium diisobutyl naphthalene sulfonate), 25 kg Auxiliary b (aqueous calcium stearate emulsion), and 595 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 18.0%. 
     In this example, the benzoxazine resin was bisphenol F/aniline benzoxazine resin having the bisphenol F/MDA bicyclic structure. 
     Example 14 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 50 kg blocked isocyanate, 60 kg benzoxazine resin, 500 kg butyronitrile latex, 15 kg Auxiliary a (Tween 20), 25 kg Auxiliary b (sodium hexametaphosphate), and 350 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 35%. 
     In this example, the benzoxazine resin was bisphenol F/aniline benzoxazine resin having the bisphenol F/MDA bicyclic structure. 
     Example 15 
     The environment-friendly impregnation solution of the invention, in percentage by weight, consisted of the following raw materials: 10 kg blocked isocyanate, 100 kg benzoxazine resin, 300 kg carboxylic styrene-butadiene latex, 15 kg Auxiliary a (Tween 80), 25 kg Auxiliary b (sodium hexametaphosphate), and 550 kg demineralized water, wherein the total weight of the respective components was 1000 kg; the solid content of the obtained impregnation solution was 30%. 
     In this example, the benzoxazine resin was bisphenol A/aniline benzoxazine resin having the bisphenol A/aniline bicyclic structure. 
     The environment-friendly impregnation solutions of the invention in Examples 1-15 were prepared as follows: 
     a) firstly, weighing the respective raw materials in a ratio according to the formula of the environment-friendly impregnation solution described in any one of Examples 1-15; 
     b) adding the weighed blocked isocyanate and Auxiliary a into demineralized water and stirring uniformly to obtain Composition 1; 
     c) then adding Auxiliary b to the obtained Composition 1 and stirring uniformly to obtain Composition 2; 
     d) and adding special amino resin to the obtained Composition 2 and stirring uniformly, then grinding to obtain Composition 3 with a solid particle size less than 5 μm; 
     e) adding rubber latex to the obtained Composition 3, and stirring uniformly to obtain the environment-friendly impregnation solution, followed by packaging. 
     The comparison in the related properties between the environment-friendly impregnation solution of the invention obtained from any of Examples 1-15 and the existing traditional products was as follows: 
     Description of the impregnation method and materials in the examples: Examples 1-15 of the invention all adopted one-bath impregnation method. In order to ensure the consistency and comparability of the experimental data, in the existing product 1 used as a control sample, Dacron was used as the fiber framework material, which was completely the same as that in Examples 1-5 of the invention, and the impregnation solution was RFL system; in the existing product 2, Chinlon 66 was used as the fiber framework material, which was completely the same as that in Examples 6-10 of the invention, and the impregnation solution was RFL system; in the existing product 3, Chinlon 6 was used as the fiber framework material, which was completely the same as that in Examples 11-15 of the invention, and the impregnation solution was RFL system. Description of the test method of samples from the Examples: the cords impregnated with the impregnation solution of any of Examples 1-15 of the invention or with the existing products 1-3 were tested as follows: the dip pick-up was determined by dissolving the impregnated cord fabrics with a specific solvent according to GB/T30310-2013 method, and measuring the remaining solid amount; H adhesive force was determined by measuring the force required for pulling out single cord from a vulcanized rubber block according to GB/T2942-2009 method; the peel adhesion from surface was determined by peeling off the sample die blank made of impregnated cord fabrics and rubber at a constant speed by a tensile testing machine according to GB/T32109-2015 method, and the middle peak value of peeling force was the adhesive peeling strength; tensile properties were determined by, under specified conditions, fixing the impregnated cord on a CRE tensile machine, and applying a tensile force at a constant speed until the cord broken according to GB/T32108-2015 method; a dry heat shrinkage was determined by measuring the shrinkage of impregnated cord fabrics over a period of time under hot air at a constant temperature according to GB/T30312-2013 method. 
     The formulas and test results of the impregnation solutions of Examples 1-5 of the invention and the existing product 1 were shown in Table 1. 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Formulas and test results of the Impregnation solutions of Examples 1-5 and the existing product 1 
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                   
                   
                   
                   
                   
                   
                 Existing 
                 Gb 
               
               
                   
                   
                   
                   
                   
                   
                 product 
                 reference 
               
               
                 Item 
                 Example 1 
                 Example 2 
                 Example 3 
                 Example 4 
                 Example 5 
                 1 
                 value 
               
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 Fiber 
                 Dacron 
                 Dacron 
                 Dacron 
                 Dacron 
                 Dacron 
                 Dacron 
                 Chinion 66 
               
               
                   
                 (1440 dtex/2) 
                 (1440 dtex/2) 
                 (1440 dtex/2) 
                 (1440 dtex/2) 
                 (1440 dtex/2) 
                 (1440 dtex/2) 
                 (1400 dtex/2) 
               
            
           
           
               
               
               
               
               
               
               
               
               
            
               
                 Impregnation 
                 Demineralized 
                 70.5%  
                 54.5%  
                 59.5%  
                  35% 
                 54% 
                 RFL 
                   
               
               
                 solution 
                 water 
                   
                   
                   
                   
                   
                 (resorcinol- 
               
               
                 formula 
                 Blocked 
                  15% 
                  10% 
                   5% 
                   5% 
                  1% 
                 formaldehyde- 
               
               
                   
                 isocyanate 
                   
                   
                   
                   
                   
                 latex system) 
               
               
                   
                 Special 
                 0.5% 
                 1.5% 
                 1.5% 
                 6.0% 
                 10% 
               
               
                   
                 amino resin 
               
               
                   
                 Rubber latex 
                  10% 
                  30% 
                  30% 
                  50% 
                 30% 
               
               
                   
                 Auxiliary a 
                 1.5% 
                 1.5% 
                 1.5% 
                 1.5% 
                 1.5%  
               
               
                   
                 Auxiliary b 
                 2.5% 
                 2.5% 
                 2.5% 
                 2.5% 
                 2.5%  
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 Solid content % 
                  15% 
                  24% 
                  18% 
                 35.5%  
                 30% 
                   
                   
               
               
                 Dip pick-up/% 
                 4.6 
                 4.8 
                 5.1 
                 5.1 
                 5.0 
                 5.0 
                 5.0 ± 1.0 
               
               
                 H adhesive 
                 137.2 
                 142.4 
                 146.3 
                 147.5 
                 147.2 
                 147.1 
                 High-class: 
               
               
                 force (N/1.0 cm) 
                   
                   
                   
                   
                   
                   
                 147.0 
               
               
                   
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                   
                   
                   
                   
                   
                   
                 137.2 
               
               
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                 127.4 
               
               
                 Adhesive peeling properties 
               
            
           
           
               
               
               
               
               
               
               
               
               
            
               
                 Tensile 
                 Breaking 
                 201.7 
                 209.4 
                 215.4 
                 216.8 
                 217.2 
                 215.9 
                 High-class: 
               
               
                 properties 
                 strength/N≥ 
                   
                   
                   
                   
                   
                   
                 215.6 
               
               
                 test: 
                   
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 211.7 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 205.8 
               
               
                   
                 Elongation 
                 18.7 
                 19.0 
                 19.2 
                 19.2 
                 19.3 
                 19.1 
                 19.0  
               
               
                   
                 at break/%≥ 
               
               
                   
                 Constant-load 
                 8.2 
                 8.5 
                 8.7 
                 8.7 
                 8.7 
                 8.5 
                 High-class: 
               
               
                   
                 elongation/ 
                   
                   
                   
                   
                   
                   
                 9.0 ± 0.6 
               
               
                   
                 % 66.6N 
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 9.0 ± 0.8 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 9.0 ± 1.0 
               
               
                   
                 Variation 
                 4.4 
                 4.2 
                 3.8 
                 3.7 
                 3.8 
                 3.8 
                 High-class: 
               
               
                   
                 coefficient of 
                   
                   
                   
                   
                   
                   
                 3.8 
               
               
                   
                 breaking 
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                 strength/%≤ 
                   
                   
                   
                   
                   
                   
                 4.8 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 5.8 
               
               
                   
                 Variation 
                 6.5 
                 6.3 
                 6.2 
                 6.3 
                 6.3 
                 6.2 
                 High-class: 
               
               
                   
                 coefficient of 
                   
                   
                   
                   
                   
                   
                 6.3 
               
               
                   
                 elongation at 
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                 break/%≤ 
                   
                   
                   
                   
                   
                   
                 7.3 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 8.3 
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 Dry heat 
                 5.1 
                 5.0 
                 5.0 
                 4.9 
                 5.0 
                 5.0 
                 5.0 
               
               
                 shrinkage/%&lt; 
               
               
                   
               
            
           
         
       
     
     The formulas and test results of the impregnation solutions of Examples 6-10 of the invention and the existing product 2 were shown in Table 2. 
     
       
         
           
               
             
               
                 TABLE 2 
               
             
            
               
                   
               
               
                 Formulas and test results of the impregnation solutions of Examples 6-10 of the invention and the existing product 2 
               
            
           
           
               
               
            
               
                   
                 Item 
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                   
                   
                   
                   
                   
                   
                   
                 Gb 
               
               
                   
                 Example 
                 Example 
                 Example 
                 Example 
                 Example 
                 Existing 
                 reference 
               
               
                   
                 6 
                 7 
                 8 
                 9 
                 10 
                 product 2 
                 value 
               
            
           
           
               
               
            
               
                   
                 Fiber 
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                   
                 Chinlon 66 
                 Chinion 66 
                 Chinion 66 
                 Chinion 66 
                 Chinion 66 
                 Chinion 66 
                 Chinion 66 
               
               
                   
                 (1400 dtex/2) 
                 (1400 dtex/2) 
                 (1400 dtex/2) 
                 (1400 dtex/2) 
                 (1400 dtex/2) 
                 (1400 dtex/2) 
                 (1400 dtex/2) 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
            
               
                 Impregnation 
                 Demineralized 
                 70.5%  
                 54.5%  
                 59.5%  
                 35% 
                 54% 
                 RFL 
                   
               
               
                 solution 
                 water 
                   
                   
                   
                   
                   
                 (resorcinol- 
               
               
                 formula 
                 Blocked 
                  15% 
                  10% 
                     5% 
                  5% 
                  1% 
                 formaldehyde- 
               
               
                   
                 isocyanate 
                   
                   
                   
                   
                   
                 latex 
               
               
                   
                 Special 
                 0.5% 
                 1.5% 
                 1.5% 
                 6.0%  
                 10% 
                 system) 
               
               
                   
                 amino resin 
               
               
                   
                 Rubber latex 
                  10% 
                  30% 
                  30% 
                 50% 
                 30% 
               
               
                   
                 Auxiliary a 
                 1.5% 
                 1.5% 
                 1.5% 
                 1.5%  
                 1.5%  
               
               
                   
                 Auxiliary b 
                 2.5% 
                 2.5% 
                 2.5% 
                 2.5%  
                 2.5%  
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 Solid content/% 
                  15% 
                  24% 
                  21% 
                 31% 
                 30% 
                   
                   
               
               
                 Dip pick-up/% 
                 4.8 
                 5.0 
                 5.1 
                 5.0 
                 5.0 
                 5.0 
                 5.0 ± 1.0 
               
               
                 H adhesive force (N/1.0 cm) 
                 135    
                 139    
                 145    
                 150    
                 148    
                 146    
                 High-class: 
               
               
                   
                   
                   
                   
                   
                   
                   
                 147.0 
               
               
                   
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                   
                   
                   
                   
                   
                   
                 137.2 
               
               
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                 127.4 
               
               
                 Adhesive peeling properties 
               
            
           
           
               
               
               
               
               
               
               
               
               
            
               
                 Tensile 
                 Breaking 
                 185.7  
                 199.2  
                 217.0  
                 219.4  
                 216.3  
                 216.1  
                 High-class: 
               
               
                 properties 
                 strength/N≥ 
                   
                   
                   
                   
                   
                   
                 215.6 
               
               
                 test: 
                   
                   
                   
                   
                   
                   
                   
                 First-class : 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 211.7 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 205.8 
               
               
                   
                 Elongation at 
                 17.7  
                 19.2  
                 19.6  
                 19.9  
                 19.4  
                 19.1  
                 19.0 
               
               
                   
                 break/%≥ 
               
               
                   
                 Constant-load 
                 8.2 
                 9.0 
                 8.9 
                 8.5 
                 9.2 
                 9.0 
                 High-class: 
               
               
                   
                 elongation/% 
                   
                   
                   
                   
                   
                   
                 9.0 ± 0.6 
               
               
                   
                 66.6 N 
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 9.0 ± 0.8 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 9.0 ± 1.0 
               
               
                   
                 Variation 
                 3.8 
                 4.3 
                 3.7 
                 3.9 
                 3.6 
                 3.8 
                 High-class: 
               
               
                   
                 coefficient 
                   
                   
                   
                   
                   
                   
                 3.8 
               
               
                   
                 of breaking 
                   
                   
                   
                   
                   
                   
                 First-class : 
               
               
                   
                 strength/%≤ 
                   
                   
                   
                   
                   
                   
                 4.8 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 5.8 
               
               
                   
                 Variation 
                 6.2 
                 6.4 
                 6.4 
                 6.1 
                 6.0 
                 6.2 
                 High-class: 
               
               
                   
                 coefficient 
                   
                   
                   
                   
                   
                   
                 6.3 
               
               
                   
                 of elongation 
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                 at break/%≤ 
                   
                   
                   
                   
                   
                   
                 7.3 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 8.3 
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 Dry heat shrinkage/% &lt; 
                 5.0 
                 5.0 
                 4.9 
                 5.0 
                 4.8 
                 5.0 
                  5.0 
               
               
                 150° C./30 min 
               
               
                   
               
            
           
         
       
     
     The formulas and test results of the impregnation solutions of Examples 11-15 of the invention and the existing product 3 were shown in Table 3. 
     
       
         
           
               
             
               
                 TABLE 3 
               
             
            
               
                   
               
               
                 Formulas and test results of the impregnation solutions of Examples 11-15 of the invention and the existing product 3 
               
            
           
           
               
               
            
               
                   
                 Item 
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                   
                   
                   
                   
                   
                   
                   
                 Gb 
               
               
                   
                 Example 
                 Example 
                 Example 
                 Example 
                 Example 
                 Existing 
                 reference 
               
               
                   
                 11 
                 12 
                 13 
                 14 
                 15 
                 product 3 
                 value 
               
            
           
           
               
               
            
               
                   
                 Fiber 
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                   
                 Chinion 6 
                 Chinion 6 
                 Chinion 6 
                 Chinion 6 
                 Chinion 6 
                 Chinion 6 
                 Chinion 6 
               
               
                   
                 (1400 dtex/2) 
                 (1400 dtex/2) 
                 (1400 dtex/2) 
                 (1400 dtex/2) 
                 (1400 dtex/2) 
                 (1400 dtex/2) 
                 (1400 dtex/2) 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
            
               
                 Impregnation 
                 Demineralized 
                 70.5%  
                 54.5%  
                 59.5%  
                 35% 
                 54% 
                 RFL 
                   
               
               
                 solution 
                 water 
                   
                   
                   
                   
                   
                 (resorcinol- 
               
               
                 formula 
                 Blocked 
                  15% 
                  10% 
                     5% 
                  5% 
                  1% 
                 formaldehyde- 
               
               
                   
                 isocyanate 
                   
                   
                   
                   
                   
                 latex 
               
               
                   
                 Special 
                 0.5% 
                 1.5% 
                 1.5% 
                 6.0%  
                 10% 
                 system) 
               
               
                   
                 amino resin 
               
               
                   
                 Rubber latex 
                  10% 
                  30% 
                  30% 
                 50% 
                 30% 
               
               
                   
                 Auxiliary a 
                 1.5% 
                 1.5% 
                 1.5% 
                 1.5%  
                 1.5%  
               
               
                   
                 Auxiliary b 
                 2.5% 
                 2.5% 
                 2.5% 
                 2.5%  
                 2.5%  
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 Solid content % 
                  15% 
                  24% 
                  18% 
                 35% 
                 30% 
                   
                   
               
               
                 Dip pick-up/% 
                 3.7 
                 4.1 
                 4.0 
                 4.3 
                 4.3 
                 4.1 
                 High-class: 
               
               
                   
                   
                   
                   
                   
                   
                   
                 4.2 ± 1.0 
               
               
                   
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                   
                   
                   
                   
                   
                   
                 4.2 ± 1.2 
               
               
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                 4.2 ± 1.2 
               
               
                 H adhesive force (N/1.0 cm) 
                 62   
                 63   
                 67   
                 71   
                 70   
                 70 
                 High-class: 
               
               
                   
                   
                   
                   
                   
                   
                   
                 70 
               
               
                   
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                   
                   
                   
                   
                   
                   
                 65 
               
               
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                 60 
               
               
                 Adhesive peeling properties 
               
            
           
           
               
               
               
               
               
               
               
               
               
            
               
                 Tensile 
                 Breaking 
                 92   
                 99   
                 105    
                 109    
                 110    
                 108 
                 High-class: 
               
               
                 properties 
                 strength/N&gt; 
                   
                   
                   
                   
                   
                   
                 107 
               
               
                 test: 
                   
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 102 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 97 
               
               
                   
                 Elongation 
               
               
                   
                 at break/%≥ 
               
               
                   
                 Constant-load 
                 8.3 
                 8.6 
                 8.6 
                 8.4 
                 8.4 
                 8.3 
                 High-class: 
               
               
                   
                 elongation/% 
                   
                   
                   
                   
                   
                   
                 8.0 ± 0.8 
               
               
                   
                 33.0 N 
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 8.0 ± 1.0 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 8.0 ± 1.0 
               
               
                   
                 Variation 
                 5.5 
                 5.2 
                 5.2 
                 5.0 
                 5.0 
                 5.0 
                 High-class: 
               
               
                   
                 coefficient 
                   
                   
                   
                   
                   
                   
                 5.0 
               
               
                   
                 of breaking 
                   
                   
                   
                   
                   
                   
                 First-class: 
               
               
                   
                 strength/%&lt; 
                   
                   
                   
                   
                   
                   
                 6.0 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Qualified: 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 6.5 
               
               
                   
                 Variation 
               
               
                   
                 coefficient 
               
               
                   
                 of elongation 
               
               
                   
                 at break/%≤ 
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 Dry heat shrinkage/%&lt; 
                 4.7 
                 4.5 
                 4.5 
                 4.4 
                 4.4 
                 4.4 
                 4.5 
               
               
                   
               
            
           
         
       
     
     The results in Table 1-3 showed that the impregnation solution of the invention without resorcinol, formaldehyde, and the like showed a good adhesive effect between Dacron cord and rubber, achieving the same adhesive level as the traditional RFL, and can completely substitute the RFL impregnation solution. 
     Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present invention but not to limit the same; although the present invention has been described in detail with reference to the foregoing examples, those skilled in the art would understand that the technical solutions described in the foregoing examples can still be modified or some technical features can be equivalently substituted, and these modifications or substitutions do not make the essence of the corresponding technical solutions departing from the spirit and scope of the technical solutions of various embodiments of the present invention. 
     INDUSTRIAL APPLICABILITY 
     The invention provides an environment-friendly impregnation solution and a method for preparing the same. The environment-friendly impregnation solution comprises the following raw materials in percentage by weight: 1-15% of blocked isocyanate, 0.5-10% of special amino resin, 10-50% of rubber latex, 1-5% of auxiliaries, and the balance of water, wherein the sum of the weight percentage of each component is 100%. The impregnation solution of the invention does not contain toxic and harmful substances such as formaldehyde and resorcinol, and the preparation method thereof is simple, easy to operate, short in production cycle, and has a high safety factor, thus ensuring the impregnation solution preparation and impregnation processes are safe and environment-friendly.