[Technology] Mutual citations and related application (s) This application claims the benefit of priority based on the date of December 18, 2017 Korea Patent Application No. 10-2017-0174518, and all information disclosed in the literature of the Korea patent application are included as part of the specification. The present invention. Relates to ethylene vinyl acetate copolymers, and relates to a method of manufacturing the same, and more particularly, mitgeu preparation of ethylene vinyl acetate copolymer having an excellent water sexual characteristics such as mechanical strength with a high cross-linking to help. [Background Art] Ethylene was vinyl acetate ethylene (ethylene) and vinyl acetate is that used ranges from a soft material such as hot melt adhesives from a hard material to the content of the vinyl acetate, a copolymer very wide in (vinyl acetate), determined relative to polyethylene Castle the lower has excellent low-temperature characteristics and impact resistance characteristics. Then, the ethylene vinyl acetate has, and excellent in electrical insulating property and a withstand voltage property, and the transparency and the barrier property, adhesive property, and is excellent in the tube, packing material, electric wire coating material, electrical insulating products, such as UV properties of a thermoplastic polymer or rubber character, widely used tape, adhesive, or the like, and various types of sheets, recently, expanding the working range of the photoelectric device protective film or a sealing material such as a solar cell. In general, ethylene vinyl acetate copolymers autoclave (Autocl ave) or tubular (Tubular) there be prepared in a reactor, generally of ethylene-vinyl acetate produced in the autoclave reactor the molecular weight distribution is wide, and the ethylene in the tubular reactor vinyl acetate is characterized by a narrow molecular weight distribution, it is common to choose to manufacture the reactor according to the application. However, back-mixing (back-mixing) takes place when using an autoclave reactor, even while it is possible to maintain a high reaction temperature, yodongseong plug flow (turbulent plug f low) tubular reactor takes place the mixing (mixing) by there is the advantage that can produce an ethylene vinyl acetate copolymer having a high vinyl acetate content of more than the case of using a. The ethylene vinyl acetate copolymer is generally known that a low mechanical strength compared to a high transparency and adhesion and gajina polyethylene. When a lot recently to utilize ethylene vinyl acetate copolymer product as the encapsulant that protects the cells of the photovoltaic module from moisture and dust, wherein the more the mechanical strength may indicate a higher encapsulant performance. Therefore, the researchers required conditions for the production method to improve the mechanical strength of the ethylene vinyl acetate copolymer. [Detailed Description of the Invention] [SUMMARY] The present invention is also to provide an ethylene vinyl acetate copolymer and a method for manufacturing the same with a high degree of crosslinking as that in order to solve the problems as described above, polymerization using a cross-linking agent is reduced by controlling the autoclave, the reactor temperature and the heat of polymerization . [Technical Solution] Above and provides an ethylene vinyl acetate copolymer to meet the conditions of, according to one embodiment of the present invention (1) to (4) in order to solve the problem: (1) Cross-linking degree: 85% or more (2) The content of vinyl acetate: 25 - relative to the total weight of copolymer 35% by weight (3) a melt index (190 ° C, 2.16kg): 20 to 30 g / 10 bun 4 * / [], the ratio of: 5500 to 7500 (Ri * is the shear viscosity (complex scosi vi ty at zero shear) measured from the zero point and 160 ° C, [] is the inherent viscosity measured at 25 ° C) In addition, according to another aspect of the invention, the presence of initiator, ethylene monomers and vinyl acetate monomer to an autoclave (Autoclave) comprising the step of polymerizing in a reactor, wherein the reactor is at least three-stage reaction zone 2019/124675 1»（：1^1{2018/010168 It includes and satisfies the relationship of the temperature of the temperature 12> or more of the first-stage reaction zone 03), in between the reaction over the first-stage reaction from the bottom zone temperature 01)> from the top of at least one end region, and the difference between kkeugwa 2 a scalar, and the heat of polymerization in accordance with the difference between the input temperature of the temperature of the ethylene vinyl acetate copolymer was prepared in the reactor, the monomer to be introduced into the reactor to meet the £ 1 Rahal time, ᅀ 17 <2.5. 【Effects of the Invention】 Ethylene vinyl acetate copolymers according to the present invention can bring the water sexual characteristics optimized with a high degree of crosslinking, it can exhibit excellent effects in terms of mechanical strength. Accordingly, it can be useful for a solar module. The production method of the ethylene-vinyl acetate copolymers according to the present invention can be made of ethylene vinyl acetate copolymer having a high degree of crosslinking with the crosslinking agent amount reduction through the polymerization autoclave reactor temperature and heat of polymerization control. [Brief description of drawings] 1 is Examples 1-4, and comparison of the ethylene vinyl acetate copolymer in Example 1 is a graph showing the relationship between ratio and the degree of crosslinking. [Best mode for practicing the invention; Used herein it is to be used to describe only the exemplary embodiments, and are not intended to limit the present invention. Expression in the singular number include a plural forms unless the context clearly indicates otherwise. As used herein, ''; comprises, "" is provided with "or" gajida '', etc. The term embodiments the features, steps, components or geotyiji to specify that these exist hangeotyi combination, step or one or more other characteristics or more of , configured to be understood an element, or the presence or possibility of a combination of these things that it does not rule out in advance. Means the temperature: Unless otherwise stated in this specification, "room temperature" "23 ± 2 is d, specifically, 251. The invention will be described in can fall various changes may illustrate a bar, a particular embodiment which may have a different form and detail below. This, however, is by no means to restrict the invention to the particular form disclosed, it is to be understood as embracing all included in the spirit and scope of the present invention changes, equivalents and substitutes. It is decided more particularly described with reference to the production method of the ethylene-vinyl acetate copolymers according to the specific implementation of the invention below. Ethylene vinyl acetate copolymer in accordance with one embodiment of the invention is to Should satisfy the condition of (1) to (4): (1) Cross-linking degree: 85% or more (2) The content of vinyl acetate: 25 to 35% by weight based on the total weight of copolymer (3) a melt index (190 ° C, 2.16kg): 20 to 30g / 10 bun (4) n * ratio / [n]: 5500 to 7500 ( * Is the shear viscosity (complex scosi vi ty at zero shear) measured from the zero point and 160 ° C, [] is the inherent viscosity measured at 25 ° C) Degree of crosslinking of the ethylene-vinyl acetate copolymer may be increased to increase the (Peak molecul ar weight) portion (port ion) or more on Mp (permeat ion chromatography gel) GPC. Euroneun and method of increasing the part Mp or more and a method of increasing the molecular weight and the chain branch LCBdong). By the present invention, controlling the polymerization autoclave reactor temperature and the heat of polymerization, as described below, as a cross-linking agent amount reduction can increase the degree of crosslinking of the ethylene-vinyl acetate copolymer. Specifically, ethylene-vinyl acetate copolymer in accordance with one embodiment of the invention has a more than 85% crosslinking degree. In this way it can exhibit a mechanical strength properties improved while maintaining a high adhesive strength by having a high degree of crosslinking. If the degree of crosslinking is less than 85% there is a risk of the mechanical strength properties and adhesive strength deteriorate. More specifically, has a 85 to 95%, or 86 to the degree of crosslinking of 90%. In the present invention, the ethylene vinyl acetate copolymer, the degree of crosslinking, the ethylene-vinyl addition of the crosslinking agent to the acetate copolymer, manufactured and heat lamination of the film on the sheet (Thermal Laminat ion) and allowed to stand at toluene (toluene) Fu dry sheet of polymer measuring the weight, and can be determined from, the weight ratio of the value after dried, and the sheet on the weight of the toluene value former sheet. Specifically, the base resin (Base After the resin) of ethylene vinyl acetate (EV) and then a mixture of cross-linking agent to the copolymer produced in the sheet, in laminating equipment and crosslinking 140 ° C, 14 minutes and 30 seconds to 15 hours the crosslinked sheet in toluene (toluene) value as for 3 hours to dry and weighed. After the measurement value before the toluene sheet weight (Wi), sheet weight (W dried d) to the degree of crosslinking by using a value calculated according to the following grinding 1. Equation 1 Degree of crosslinking (%) = (W d / Wi) x 100 Further, the ethylene-vinyl acetate copolymer has a vinyl acetate content of 25 to 35% by weight based on the weight of copolymer species. If the ethylene-vinyl acetate copolymer is within a concern if the content of vinyl acetate is less than 25% by weight, the elasticity, the elastic and adhesive properties decrease and, more than 35% by weight, there is a possibility that the weather resistance decreases. More specifically, has a vinyl acetate content of 27 to 30% by weight based on the total weight of the copolymer, or 27.9 to 29% by weight, or 27.9 to 28.5% by weight. Further, the ethylene-vinyl acetate copolymer may be from 20 to 30g / 10 melt index (MI) was measured under a load of 190 ° C, 2.16kg min. With a high degree of crosslinking and a vinyl acetate content as described above, by having a low melt index of the range, it is possible to exhibit excellent workability while keeping excellent mechanical properties. If a melt index of 20 g / 10 min is less than there is a possibility of lowering workability, exceeds a melt index of 30 g / 10 bun there is a risk of mechanical property degradation. More specifically, it has a melt index of days 22 to 28 g / 10 minutes, or 22 to 25.5 g / 10 minutes of the ethylene-vinyl acetate copolymer. Further, the ethylene-vinyl acetate copolymer is the ratio of 5500 to 7500 * / U]. a * / [ri] and if the ratio value is less than 5500, and there is a risk of cross-linking is also caused by low molecular weight degradation increases, there is a fear of lowering the workability, the molecular weight increases excessively if the addition exceeds 7500. More specifically, the number of days is 5800 to 7200. On the other hand, ri * / [ri] Zero shear viscosity of the non-a * of the (complex vi scosi ty at zero shear) is herein to mean the viscosity of when the angular frequency (angular frequency) 0, rotary rheometer (rotat ional rheometer) is a parameter obtained through a frequency sweep (sweep frequency) of the data (data points) rohoe type rheometer only analysis program (program analysi s) installed in jeukjeong the range of the actual measured angular frequency available using the. The frequency sweep is once using the typical Rheometer 160 ° is measured at a temperature C. Further, Newton using, rotary rheometer is a value obtained by extrapolating the reduced viscosity or inhibit parent viscosity (inherent vi scos i ty) of the polymer solution to a polymer concentration of 0, the intrinsic viscosity (intr insic vi scosi ty) of the [] (vi Newtoni an scosi ty) obtained by the measurement. According to the present invention - the zero shear viscosity of the time using a typical rheometer 160 as melt viscosity measurement methods ° was measured on the C, [] The intrinsic viscosity times room temperature for Newtonian viscosity using a type rheometer, specifically, 25 ° for It was measured in C. With the conditions of the above (1) to (4), wherein the ethylene vinyl acetate copolymer is the number of days having a 16,000 to 18,000g / mol the number average molecular weight (Mn). By having a high number average molecular weight of the above-described range it can exhibit more improved mechanical strength. More specifically, there 16,500 to 17,800g / mol number of days. Further, the ethylene-vinyl acetate copolymer may be one having a molecular weight distribution of 3.0 to 4.0 (MWD). The molecular weight distribution has a number average molecular weight means the ratio of weight average molecular weight «contrast (Mn) and (Mw / Mn), by having a molecular weight distribution within the above range it can exhibit a good workability and mechanical strength balance. More specifically, can have a molecular weight distribution of 3.2 to 3.5. On the other hand, in the present invention, the molecular weight distribution (MWD), the weight average molecular weight (Mw), mitsu average molecular weight (Mn) can be measured by size exclusion chromatography (況 C). More specifically, the present invention, ethylene vinyl acetate copolymers Samples of l, 2,4-TCB (l, 2,4-tr ichlorobenzene) the temperature was dissolved, to the 1,2,4-TCB as the mobile phase 125 ° C and under the conditions of a flow rate of lml / min to obtain each of the weight-average molecular weight and number average molecular weight, calculated for a molecular weight distribution (ratio of weight average molecular weight / number-average molecular weight) from its value. At this time, the column of 況 C may be used as the PLgel 10 um Mixed-B (Agi lent Co., Ltd.). Ethylene vinyl acetate copolymers as described above can implement the obsolete sexual characteristics and reduces the temperature difference in-flight during the polymerization reaction using an autoclave reactor, and, by reducing the heat of polymerization. Specifically, ethylene vinyl acetate, according to one embodiment of the present invention, in the presence of an initiator, the ethylene monomer and the vinyl acetate monomer can be produced by a production method including the step of polymerizing in an autoclave (Autocl ave) reactor, and , in which the reactor is at least comprises a three-stage or more reaction zones, at least one-stage reaction from the bottom zone temperature (T1)> temperature (T2) of the above first-stage reaction zone from the top> single-stage or more reaction zones in between ( satisfy the relation of the temperature T3), and the T1 and d the difference (T1-T2) of T2 AT, and the input of the monomer and temperature of the ethylene-vinyl acetate copolymer produced in the reactor, is introduced into the reactor temperature when the polymerization Rahal Q column according to the difference, Scotland! satisfies' / 0 <2.5 shed. More specifically, the reactor comprises a reaction zone 11, is the temperature of the reaction zone of the five-stage from the lowermost stage, T2 is Ago temperature of the reaction zone of the four stages from the top, T3 is the meantime the two ends of the the temperature may be in the reaction zone. If the temperature in the reactor conditions, the AT / Q> 2.5 days, sueopda implement the physical properties of the ethylene vinyl acetate copolymer. More specifically, 0.5 ) and the number average molecular weight () were measured by size exclusion chromatography 0 比 防). 此 easy 10_ Was measured, 1, 2,4-106 (1,2,4-1 (土1 01此61126116 by a) a rule mobile phase 1251: 1 and a temperature of 1 was measured at a flow rate of ^ / ^ ^ conditions !. In detail, the following Examples and Comparative Examples of ethylene-vinyl acetate copolymer of the sample, respectively eseo 10 1 was dissolved in a concentration of 5 to 1,2,4-11¾犯/ 10, was supplied in an amount of 200 naneu, styrene - by using a calibration curve formed by using the standard were calculated weight average molecular weight (¾加) a molecular weight distribution (ratio of weight average molecular weight / number-average molecular weight) value from mitsu induce a number average molecular weight (), and its value. The molecular weight of the polystyrene standard was used 9 kinds of 9,475,000, 597,500, 19 920, 3,507,000, 224,900, 9960, 1.956 million, 0 74 800, 2980. (5) / [], the ratio of Zero shear viscosity * are times with a melt viscosity measuring method using a rheometer model 1601: was measured on, the Newtonian viscosity by using a rotary type rheometer is the intrinsic viscosity of [] 25 ° (: was measured at. 5 In addition, Examples 1-4 and Comparative comparing the ratio and the degree of crosslinking between the example 1 of the ethylene vinyl acetate copolymer and II [it], and the results are shown in Figure 1; [Table 2] 2019/124675 1»（：1^1{2018/010168 Experimental results carried out are manufactured by controlling the temperature and the heat of polymerization in the reactor at a certain range in accordance with the invention Examples 1 to 4 of ethylene vinyl acetate copolymers, Comparative Example 1 as compared to a low degree, indicating the high crosslinking help vinyl acetate content It exhibited a value. [Claims] [Claim 1] (1) to ethylene vinyl acetate copolymers which satisfy the condition of (4): (1) Cross-linking degree: 85% or more (2) The content of vinyl acetate: 25 to 35% by weight based on the total weight of copolymer (3) a melt index (190 ° 0, 2.161 ¾) : 20 to 30 § / 10 bun 4 * /] ratio of: 5500 to 7500 ( * Is 160 ° (:, and a zero shear viscosity measured at, [] is an intrinsic viscosity measured at 25) [Claim 2] According to claim 1, The ethylene vinyl acetate copolymer is 16,000 to 18,000 § / 01 may have an average molecular weight thereof, ethylene vinyl acetate copolymers. [Claim 3] The method of claim 1 wherein ' The ethylene vinyl acetate copolymer having a molecular weight distribution of 3.0 to 4.0 , an ethylene vinyl acetate copolymer. [Claim 4] In the presence of an initiator, the ethylene monomer and vinyl acetate monomer comprising the step of polymerizing in an autoclave reactor, Wherein the reactor comprises at least three-stage reaction zone, At least one step from the lowermost reaction zone temperature (比)> temperature奸2) of at least the first-stage reaction zone from the top> or more first-stage reaction in the meantime . Meet the temperature relationship of the area.奸幻and ' La scan the difference between the II and 12, and the ethylene in the reactor 2019/124675 1 »(1 ^ 1 {2018/010168 When referred to the heat of polymerization in accordance with the temperature of the vinyl acetate copolymer, a difference between the input temperature of the monomer to be introduced into the reactor, ^ 1/0