Manufacturing technology of ceramic flame-retardant silicone rubber synthetic leather and synthetic leather

文档序号:1636072 发布日期:2020-01-17 浏览:23次 中文

阅读说明:本技术 一种陶瓷化阻燃硅橡胶合成革的制造技术及该合成革 (Manufacturing technology of ceramic flame-retardant silicone rubber synthetic leather and synthetic leather ) 是由 陶玉红 胥晓群 于 2019-10-14 设计创作,主要内容包括:本发明公开了一种陶瓷化阻燃硅橡胶合成革的制造技术,其包括以下步骤:步骤1、制备混合陶瓷填料,制备陶瓷化硅橡胶基胶,该陶瓷化硅橡胶基胶的组成原料中包括所述混合陶瓷填料。还公开了一种陶瓷化阻燃硅橡胶合成革,其由贝斯、陶瓷化强粘接底胶、陶瓷化发泡中间层和陶瓷化面胶依次层叠而成;所述陶瓷化强粘接底胶、陶瓷化发泡中间层和陶瓷化面胶层的组成原料中均包括陶瓷化硅橡胶基胶,该陶瓷化硅橡胶基胶的组成原料中包括混合陶瓷填料。本发明专利将陶瓷化硅橡胶进行发泡处理,既可以降低硅橡胶的密度和成本,又可以使陶瓷化硅橡胶的硬度大大降低,手感变成非常柔软。本发明方法不使用有机溶剂,工艺简单,更加环保,生产效率更快。(The invention discloses a manufacturing technology of ceramic flame-retardant silicone rubber synthetic leather, which comprises the following steps: step 1, preparing a mixed ceramic filler, and preparing a ceramic silicon rubber base rubber, wherein the raw materials of the ceramic silicon rubber base rubber comprise the mixed ceramic filler. The ceramic flame-retardant silicone rubber synthetic leather is formed by sequentially laminating bass, ceramic strong-adhesion primer, a ceramic foaming intermediate layer and ceramic surface glue; the ceramic strong bonding primer, the ceramic foaming intermediate layer and the ceramic surface glue layer all comprise ceramic silicon rubber-based glue, and the ceramic silicon rubber-based glue comprises mixed ceramic filler. The ceramic silicon rubber is foamed, so that the density and the cost of the silicon rubber can be reduced, the hardness of the ceramic silicon rubber can be greatly reduced, and the hand feeling of the ceramic silicon rubber is very soft. The method does not use organic solvent, has simple process, is more environment-friendly and has higher production efficiency.)

1. The manufacturing technology of the ceramic flame-retardant silicone rubber synthetic leather is characterized by comprising the following steps of:

step 1, preparing a mixed ceramic filler, and preparing a ceramic silicon rubber base rubber, wherein the raw materials of the ceramic silicon rubber base rubber comprise the mixed ceramic filler.

2. The manufacturing technology of the ceramic flame-retardant silicone rubber synthetic leather according to claim 1, wherein in the step 1, 80-100 parts of kaolin clay specially used for ceramics is subjected to high-temperature calcination in a furnace for 3-5 hours, then mixed ceramic flame retardant of 5-10 parts of antimony trioxide, 5-10 parts of aluminum hydroxide and 3-5 parts of magnesium hydroxide is added into 100-150 parts of alkane solvent, 10-20 parts of silane coupling agent is added, the pH value is adjusted to 8-10 by ammonia water, the temperature is increased to 50-60 ℃, stirring reaction is carried out for 3-5 hours, and then the alkane solvent is subjected to vacuum filtration and recovery for use, so as to obtain the pretreated mixed ceramic filler.

3. The manufacturing technology of the ceramic flame-retardant silicone rubber synthetic leather as claimed in claim 1, wherein in the step 1, 50-80 parts of high-viscosity vinyl silicone oil, 20-50 parts of the pretreated mixed ceramic filler, 10-20 parts of the reinforcing filler, 3-5 parts of the silane coupling agent and 3-5 parts of silazane are put into a kneader, the temperature is controlled below 60 ℃ for refining for 3 hours, the temperature is increased to 90-95 ℃ for refining for 2 hours, 130-135 ℃ for refining for 2 hours, 170-175 ℃ for refining for 1 hour, and 170-175 ℃ high temperature waste removal is carried out for 3 hours to obtain the ceramic silicone rubber base rubber.

4. The manufacturing technology of the ceramic flame-retardant silicone rubber synthetic leather according to any one of claims 1 to 3, characterized by comprising the following steps:

step 2, preparing ceramic surface glue;

step 3, preparing a ceramic foaming intermediate layer;

step 4, preparing ceramic strong bonding primer;

step 5, coating the ceramic surface glue on release paper or leather grain paper, conveying the release paper or leather grain paper to a tunnel furnace, and vulcanizing the release paper or leather grain paper for 5 to 10 minutes at the temperature of 80 to 100 ℃; coating the ceramic foaming middle layer on a ceramic surface adhesive, conveying the ceramic foaming middle layer to a tunnel furnace, and vulcanizing the ceramic foaming middle layer for 5 to 10 minutes at the temperature of 100-120 ℃; coating the ceramic strong bonding primer on the ceramic foaming intermediate layer, attaching the ceramic strong bonding primer to the Bass, conveying the ceramic strong bonding primer to a tunnel furnace, vulcanizing the ceramic strong bonding primer at the temperature of 100-120 ℃ for 5-10 minutes, peeling the release paper or the leather paper, rolling, cutting edges, and packaging to obtain the ceramic flame-retardant silicon rubber synthetic leather;

the steps 2-4 are not in sequence.

5. The manufacturing technology of the ceramic flame-retardant silicone rubber synthetic leather according to claim 4, wherein in the step 2, 1-50 parts of ceramic silicone rubber-based rubber, 3-5 parts of fluorine-silicon modified acrylic finishing agent, 1-3 parts of low hydrogen silicone oil, 0.1-0.3 part of platinum catalyst, 0.05-0.08 part of retarder and 3-5 parts of color paste pigment are put into a planetary dispersion machine and stirred uniformly.

6. The manufacturing technology of the ceramic flame-retardant silicone rubber synthetic leather according to claim 4, wherein in the step 3, 11-20 parts of ceramic silicone rubber-based rubber, 10-15 parts of high hydrogen-containing silicone oil, 0.05-0.08 part of single-component platinum catalyst, 5-10 parts of 100 ten thousand molecular weight methyl raw rubber, 5-10 parts of low viscosity vinyl silicone oil and 1-3 parts of color paste pigment are put into a planetary dispersing machine and stirred uniformly.

7. The manufacturing technology of the ceramic flame-retardant silicone rubber synthetic leather according to claim 4, wherein in the step 4, 30-50 parts of ceramic-based silicone rubber-based glue, 5-8 parts of organic silicon modified polyurethane polymer, 3-5 parts of organic silicon modified acrylic polymer, 3-5 parts of silane coupling agent, 1-3 parts of low hydrogen-containing silicone oil, 0.1-0.3 part of platinum catalyst, 0.05-0.08 part of retarder and 3-5 parts of pigment paste are put into a planetary dispersing machine and stirred uniformly.

8. The ceramic flame-retardant silicone rubber synthetic leather is characterized by being formed by sequentially laminating bass, ceramic strong-adhesion primer, a ceramic foaming middle layer and ceramic surface glue;

the ceramic strong bonding primer, the ceramic foaming intermediate layer and the ceramic surface glue layer all comprise ceramic silicon rubber-based glue, and the ceramic silicon rubber-based glue comprises mixed ceramic filler.

9. The ceramic flame-retardant silicone rubber synthetic leather according to claim 8, wherein the ceramic silicone rubber-based rubber consists of the following raw materials in parts by mass: 50-80 parts of high-viscosity vinyl silicone oil, 20-50 parts of pretreated mixed ceramic filler, 10-20 parts of reinforcing filler, 3-5 parts of silane coupling agent and 3-5 parts of silazane.

10. The ceramifying flame-retardant silicone rubber synthetic leather according to claim 8 or 9, wherein the mixed ceramic filler consists of the following raw materials in parts by mass: 80-100 parts of special kaolin panned clay for ceramics, 5-10 parts of antimony trioxide, 5-10 parts of aluminum hydroxide, 3-5 parts of magnesium hydroxide mixed ceramic flame retardant and 10-20 parts of silane coupling agent.

Technical Field

The invention relates to organic silicon and synthetic leather, in particular to a manufacturing technology of ceramic flame-retardant silicone rubber synthetic leather and the ceramic flame-retardant silicone rubber synthetic leather manufactured by the manufacturing technology.

Background

The silicone rubber synthetic leather is the most advanced technology in the artificial synthetic leather industry, is the highest-end product formed by combining technical crystallization of various industries such as textile, printing and dyeing, clothing, plastics, leather, chemical engineering, furniture, building materials and the like, is widely applied to the fields of clothing, bags, shoes and hats, soft furniture, outdoor furniture, medical treatment, automotive interior, war industry, packaging and the like, belongs to a novel green manufacturing material, is the best substitute of natural leather, can promote the artificial synthetic leather industry to be updated, and can further promote related fields to adopt the advanced technology to produce green, environment-friendly and energy-saving products. However, although the common silicone rubber synthetic leather can meet the fire protection requirement of B-1, does not produce obvious flame and dense smoke, and can be extinguished in time when leaving a goods source, under the condition of a large fire, the silicone rubber synthetic leather still burns into ashes, has poor strength, cannot form a ceramic protective layer, cannot perform fire protection on internal materials wrapped by the silicone rubber synthetic leather, and cannot meet the high requirements of special scenes (such as yachts, ships, closed rooms, airplanes, trains, automobiles, and the like).

However, the ceramized silicon rubber has a unique ceramization mechanism, so that the silicon rubber can be rapidly ceramized in the combustion process, the strength of combustion residues is greatly improved, the prepared ceramized silicon rubber synthetic leather has the advantages that a ceramic body is not cracked after combustion, the ceramic body has high bending strength, the purposes of fire prevention and fire retardation are achieved, and the ceramized silicon rubber has a wide market application prospect.

The existing ceramic flame-retardant silicone rubber is mainly applied to the cable industry to protect cables from being influenced in fire, and has the defects that the ceramic silicone rubber for the cables is too high in hardness and high in price and is not suitable to be used as a civil synthetic leather raw material.

Disclosure of Invention

The invention aims to provide a manufacturing technology of ceramic flame-retardant silicone rubber synthetic leather aiming at the problems, which does not use organic solvent, has simple process, is more environment-friendly and has faster production efficiency

The ceramic flame-retardant silicone rubber synthetic leather is low in silicone rubber hardness, excellent in mechanical property, soft in hand feeling and strong in skin-friendly feeling. When a fire disaster occurs, the ceramic flame-retardant silicon rubber can form a compact and hard ceramic layer after being burnt, so that the internal material coated by the ceramic flame-retardant silicon rubber can be protected from being burnt, and the fire spreading condition is reduced as much as possible.

A manufacturing technology of ceramic flame-retardant silicone rubber synthetic leather comprises the following steps:

step 1, preparing a mixed ceramic filler, and preparing a ceramic silicon rubber base rubber, wherein the raw materials of the ceramic silicon rubber base rubber comprise the mixed ceramic filler.

In the step 1, 80-100 parts of kaolin panned clay special for ceramics is calcined in a furnace at high temperature for 3-5 hours, then mixed ceramic fire retardant of 5-10 parts of antimony trioxide, 5-10 parts of aluminum hydroxide and 3-5 parts of magnesium hydroxide is added into 100-150 parts of alkane solvent, 10-20 parts of silane coupling agent is added, the PH value is adjusted to 8-10 by ammonia water, the temperature is raised to 50-60 ℃, stirring reaction is carried out for 3-5 hours, and then the alkane solvent is vacuum filtered and recycled to obtain the pretreated mixed ceramic filler. The conventional treatment process is only ceramic treatment and then adding mixed ceramic flame retardant, and no back-end treatment is carried out, the back end of the ceramic flame retardant is treated by the silane coupling agent, so that firstly, the ceramic flame retardant is prevented from agglomerating and is difficult to disperse uniformly when being added at the back end; secondly, in order to enable the ceramic powder to have active groups capable of reacting with the silicon rubber, the ceramic filler can only chemically react with the silicon rubber to form firm chemical bonds, so that the mechanical properties of the silicon rubber are more outstanding.

In the step 1, 50-80 parts of high-viscosity vinyl silicone oil, 20-50 parts of pretreated mixed ceramic filler, 10-20 parts of reinforcing filler, 3-5 parts of silane coupling agent and 3-5 parts of silazane are put into a kneader, the temperature is controlled below 60 ℃ for refining for 3 hours, the temperature is raised to 90-95 ℃ for refining for 2 hours, the temperature is increased to 130-plus-material 135 ℃ for refining for 2 hours, the temperature is increased to 170-plus-material 175 ℃ for refining for 1 hour, and the waste is removed at the high temperature of 170-plus-material 175 ℃ for 3 hours to obtain the ceramic silicon rubber base adhesive. The multi-stage temperature-controlled refined silicone rubber has long storage time in the later period, long quality guarantee period and excellent mechanical properties. The conventional treatment process is that the pretreated mixed ceramic filler is not added, the refined rubber is common silicon rubber, and the refined rubber can be burnt into powdered and unshaped silicon dioxide when being burnt in a big fire, so that the refined rubber has no protective effect on the internal material wrapped by the synthetic leather. The ceramic flame-retardant silicon rubber synthetic leather disclosed by the invention forms a compact and hard ceramic protective layer after being combusted, so that the internal material can be prevented from isolating a fire source and can not be combusted.

The manufacturing technology of the ceramic flame-retardant silicone rubber synthetic leather comprises the following steps:

step 2, preparing ceramic surface glue;

step 3, preparing a ceramic foaming intermediate layer;

step 4, preparing ceramic strong bonding primer;

step 5, coating the ceramic surface glue on release paper or leather grain paper, conveying the release paper or leather grain paper to a tunnel furnace, and vulcanizing the release paper or leather grain paper for 5 to 10 minutes at the temperature of 80 to 100 ℃; coating the ceramic foaming middle layer on a ceramic surface adhesive, conveying the ceramic foaming middle layer to a tunnel furnace, and vulcanizing the ceramic foaming middle layer for 5 to 10 minutes at the temperature of 100-120 ℃; coating the ceramic strong bonding primer on the ceramic foaming intermediate layer, attaching the ceramic strong bonding primer to the Bass, conveying the ceramic strong bonding primer to a tunnel furnace, vulcanizing the ceramic strong bonding primer at the temperature of 100-120 ℃ for 5-10 minutes, peeling the release paper or the leather paper, rolling, cutting edges, and packaging to obtain the ceramic flame-retardant silicon rubber synthetic leather; the conventional synthetic leather treatment process also needs to evaporate and recover the organic solvent in the raw materials, but the method does not use the organic solvent, has simple process, is more environment-friendly and has higher production efficiency.

The steps 2-4 are not in sequence.

In the step 2, 1-50 parts of ceramic silicon rubber base rubber, 3-5 parts of fluorine-silicon modified acrylic coating agent, 1-3 parts of low-hydrogen silicone oil, 0.1-0.3 part of platinum catalyst, 0.05-0.08 part of retarder and 3-5 parts of color paste pigment are put into a planetary dispersion machine and are uniformly stirred.

In the step 3, 11-20 parts of ceramic silicon rubber-based adhesive, 10-15 parts of high hydrogen-containing silicone oil, 0.05-0.08 part of single-component platinum catalyst, 5-10 parts of 100 ten thousand molecular weight methyl raw rubber, 5-10 parts of low-viscosity vinyl silicone oil and 1-3 parts of color paste pigment are put into a planetary dispersion machine and stirred uniformly. In the prior art, foaming silicon rubber is not used, so that the hand feeling of the synthetic leather becomes softer, the overall density can be reduced, and the skin-friendly feeling is stronger.

In the step 4, 30-50 parts of ceramic-based silicone rubber-based adhesive, 5-8 parts of organic silicon modified polyurethane polymer, 3-5 parts of organic silicon modified acrylic polymer, 3-5 parts of silane coupling agent, 1-3 parts of low-hydrogen silicone oil, 0.1-0.3 part of platinum catalyst, 0.05-0.08 part of retarder and 3-5 parts of pigment paste are put into a planetary dispersion machine and stirred uniformly. The silicon rubber only has two nonpolar reaction groups of vinyl and silicon hydride, and the bass often contains polar groups of hydroxyl, carboxyl, epoxy and the like, and the nonpolar reaction groups and the polar reaction groups are difficult to generate chemical reaction, so that the bonding force between the silicon rubber and the bass is poor, and the phenomenon that the silicon rubber and the bass are separated easily occurs in the long-term use process of the manufactured synthetic leather. The invention can well combine the silicon rubber and the bass.

The ceramic flame-retardant silicone rubber synthetic leather is formed by sequentially laminating bass, ceramic strong-adhesion primer, a ceramic foaming intermediate layer and ceramic surface glue;

the ceramic strong bonding primer, the ceramic foaming intermediate layer and the ceramic surface glue layer all comprise ceramic silicon rubber-based glue, and the ceramic silicon rubber-based glue comprises mixed ceramic filler.

The ceramic silicon rubber base rubber comprises the following raw materials in parts by mass: 50-80 parts of high-viscosity vinyl silicone oil, 20-50 parts of pretreated mixed ceramic filler, 10-20 parts of reinforcing filler, 3-5 parts of silane coupling agent and 3-5 parts of silazane.

The mixed ceramic filler comprises the following raw materials in parts by mass: 80-100 parts of special kaolin panned clay for ceramics, 5-10 parts of antimony trioxide, 5-10 parts of aluminum hydroxide, 3-5 parts of magnesium hydroxide mixed ceramic flame retardant and 10-20 parts of silane coupling agent.

The ceramic strong bonding primer consists of the following raw materials in parts by mass: 30-50 parts of ceramic-based silicone rubber-based adhesive, 5-8 parts of organic silicon modified polyurethane polymer, 3-5 parts of organic silicon modified acrylic polymer, 3-5 parts of silane coupling agent, 1-3 parts of low-hydrogen silicone oil, 0.1-0.3 part of platinum catalyst, 0.05-0.08 part of retarder and 3-5 parts of color paste pigment.

The ceramic foaming intermediate layer is composed of the following raw materials in parts by mass: 1-20 parts of ceramic silicon rubber-based adhesive, 10-15 parts of high hydrogen-containing silicone oil, 0.05-0.08 part of single-component platinum catalyst, 5-10 parts of 100 ten thousand molecular weight methyl raw rubber, 5-10 parts of low-viscosity vinyl silicone oil and 1-3 parts of color paste pigment.

The ceramic face glue comprises the following raw materials in parts by mass: 31-50 parts of ceramic silicon rubber base rubber, 3-5 parts of fluorine-silicon modified acrylic finishing agent, 1-3 parts of low-hydrogen silicone oil, 0.1-0.3 part of platinum catalyst, 0.05-0.08 part of retarder and 3-5 parts of color paste pigment.

The silane coupling agent is one or a combination of more than two of A-151, KH-560, KH-570, KH550, KH-792 and KH-794; the silane coupling agent has a hydrophilic reactive group and can generate chemical reaction with the bass.

The alkane solvent is a mixture of isoparaffin and straight-chain alkane with four to eight carbon atoms; the alkane solvent has good compatibility with the silane coupling agent, so that the silane coupling agent is grafted to the surface of the ceramic filler.

The viscosity of the high-viscosity vinyl silicone oil is 100000cs-200000cs, and the vinyl content is 0.03-0.05%; the silicone rubber prepared by using the high-viscosity vinyl silicone oil rubber has low hardness and excellent mechanical properties, the hardness of the silicone rubber is determined by the vinyl content, and the silicone rubber with the low vinyl content has low hardness and soft hand feeling.

The reinforcing filler is one or a composition of more than two of gas-phase white carbon black, precipitated white carbon black, silicon micropowder and calcium carbonate; the reinforcing material greatly improves the mechanical properties of the silicone oil.

The fluorine-silicon modified acrylic coating agent contains 0.3-0.5% of organic fluorine and 3-5% of silicon; the fluorine-silicon modified acrylic finishing agent can make the surface of the synthetic leather smoother, better stain resistance, dust prevention and doodling prevention effects, and also can make the silicone rubber have the function of solvent resistance, no substitute products are used, the more the content is, the smoother, the more stain resistance, the dust prevention and the doodling prevention are, but the cost can be greatly increased, the hardness is higher, and the hand feeling is harder.

The hydrogen content of the low-hydrogen silicone oil is 0.36-1.0%; the hydrogen content in the range enables the silicon rubber to be uniformly crosslinked and to have excellent mechanical properties, and the higher the hydrogen content is, the smaller the amount is used.

The hydrogen content of the high hydrogen-containing silicone oil is 1.6 percent; the hydrogen-containing silicone oil with the content can generate dehydrogenation reaction under the catalysis of the platinum catalyst, so that the silicone rubber is self-foamed, the density of the foamed silicone rubber is reduced, the hand feeling is softer, and the other content of the hydrogen-containing silicone oil can not generate dehydrogenation reaction and can not self-foam the silicone rubber.

The single-component platinum vulcanizing agent is a mixture of a common platinum vulcanizing agent and a low-activity delay agent, the platinum vulcanizing agent can be completely free of reaction at low temperature, but the reaction can be quickly carried out when the temperature reaches more than 100 ℃, and the operation time of the ceramic foaming intermediate layer is effectively prolonged; the single-component platinum vulcanizing agent is a common platinum vulcanizing agent which can coexist with a low-activity retarder and completely inhibit the activity of a platinum catalyst under a low-temperature condition (within 100 ℃), but the common platinum vulcanizing agent and the common retarder cannot coexist and must be stored separately, the common platinum vulcanizing agent and the common retarder can be mixed together when used, and platinum also has catalytic activity under the low-temperature condition. When the middle layer is foamed, a single-component platinum catalyst without reactivity at low temperature is required to be used, however, in the mixing process, the high-hydrogen silicone oil is catalyzed by the platinum catalyst to generate a self-foaming phenomenon, and the operation time of the sizing material is too short to meet the production requirement.

The common platinum vulcanizing agent is obtained by reacting chloroplatinic acid, a vinyl double-end socket and sodium bicarbonate, the low-activity retarder is diallyl maleate or diethyl fumarate, and no other substances can be substituted.

The 100 ten thousand molecular weight methyl raw rubber has no vinyl reaction group, so that the mechanical property of the foaming middle layer can be improved; the molecular weight of 100 ten thousand is the limit molecular weight of methyl raw rubber, the molecular chain length is very long, and simultaneously, as the molecular chain does not participate in the reaction, the integral hardness of the silicon rubber can be reduced, the flexibility of the silicon rubber is increased, the silicon rubber cannot be too brittle, and the mechanical property is increased.

The viscosity of the low-viscosity vinyl silicone oil is 300-500cs, and the vinyl content is 0.8-1.0%; the viscosity is lower, the molecular chain is shorter, the content of terminal vinyl is higher, the reaction crosslinking density is effectively increased, and the surface of the synthetic leather is dry and comfortable and has warm and moist feeling.

The organosilicon content of the organosilicon modified polyurethane polymer is 10-15%, and the raw material is low-viscosity hydroxy silicone oil; the low-viscosity hydroxyl silicone oil has high hydroxyl content and strong polarity, can be well compatible with polar polyurethane monomers, and is easy to participate in the synthetic reaction of polyurethane.

The organosilicon modified acrylic polymer contains 20-30% of organosilicon, and the raw material is organosilicon sol-gel; the organic silicon sol-gel is a network structure material obtained by hydrolyzing and condensing a silane coupling agent, the surface of the organic silicon sol-gel is provided with a vinyl group capable of participating in the polymerization reaction of acrylic monomers, and a large amount of organic silicon materials can be grafted into an acrylic polymer by using a small amount of vinyl groups.

The platinum catalyst is 5000ppm and can be ethanol, isopropanol, vinyl silicone oil or dimethyl silicone oil solution;

the thickness of the ceramic surface layer is 0.03-0.05mm, the thickness of the ceramic foaming layer is 0.1-0.12mm, the thickness of the ceramic strong bonding base coat is 0.03-0.05mm, the thickness of the Bass is 0.3-1.5mm, and the total thickness of the ceramic flame-retardant silicon rubber synthetic leather is 0.5-2.5 mm.

Base caliper refers to the selected caliper of the base fabric, which is available from english base.

The invention has the beneficial effects that: the existing ceramic silicon rubber has high cost and high hardness, and is not suitable for being used as a raw material of synthetic leather, but the ceramic silicon rubber is subjected to foaming treatment, so that the density and the cost of the silicon rubber can be reduced, the hardness of the ceramic silicon rubber can be greatly reduced, and the hand feeling is changed into very soft. The product is aging resistant, waterproof, breathable, yellowing resistant and wear resistant. The method does not use organic solvent, has simple process, is more environment-friendly and has higher production efficiency.

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