KR102313487B1 - Color rubber for wireless charger pads with anti-discoloration effects in natural conditions - Google Patents

Abstract

The present invention relates to colored rubber for a wireless charger pad having an effect of preventing discoloration in a natural condition. The colored rubber according to the present invention includes synthetic rubber, paraffin-based oil, carbon black, a UV blocking agent, anti-aging agent and a rainbow-preventing agent. The present invention also relates to a method for preparing colored rubber for a wireless charger pad having an effect of preventing discoloration in a natural condition. The method according to the present invention includes: a first mixing step of mixing, based on 100 parts by weight of synthetic rubber, 40-60 parts by weight of paraffin-based oil and 10-30 parts by weight of carbon black; a second mixing step of mixing 100 parts by weight of the rubber blend mixed in the first mixing step with 5-15 parts by weight of a UV blocking agent, 5-10 parts by weight of an antiaging agent and 3-7 parts by weight of a rainbow-preventing agent; an aging step of aging the rubber blend mixed in the second mixing step; a cutting step of cutting the rubber blend aged in the aging step; and a molding step of molding the rubber blend cut in the cutting step by heating the same under a pressure of 10-20 bar at a temperature of 170-200℃ for 3-5 minutes in a molding vulcanizer. According to the present invention, the colored rubber can be used under various environments, including indoor and outdoor environments and cars, through suitable additives considering the physical and chemical properties of the synthetic rubber. Particularly, when the colored rubber is applied to cars, the same can prevent generation of defects in appearance, such as surface discoloration and efflorescence, caused by oxidation in a short time upon the exposure to external UV rays, direct light and internal ozone, can assist user's convenience and can be used semi-permanently.

Description

Color rubber for wireless charger pads with anti-discoloration effects in natural conditions

The present invention relates to a color rubber for a wireless charger pad having an effect of preventing discoloration in a natural state, and more particularly, through suitable additives in consideration of the physical and chemical properties of synthetic rubber, when exposed to external ultraviolet rays, direct sunlight and internal ozone for a short period of time. It relates to a color rubber for a wireless charger pad, which prevents the appearance of defects such as surface discoloration and whitening caused by oxidation inside and has an effect of preventing discoloration in a natural state that can be used semi-permanently.

In general, a mobile device is equipped with a rechargeable secondary battery built-in battery to provide power. In order to charge the secondary battery, a separate charging device for supplying the mobile device by adjusting the household commercial power to an appropriate voltage is required. In general, the charging device and the battery are provided with separate contact terminals, respectively, and are charged by using a cable to connect them to the battery.

However, when the contact terminal protrudes to the outside in this way, it is not only aesthetically good, but also the problem of contamination of the contact terminal and the problem of poor contact easily occur. In order to solve the problem of the contact-type charging method, a wireless charger for a mobile device that charges a battery in a non-contact manner using inductive coupling between a wireless charging device having a transmitting coil and a battery having a receiving coil built in the mobile device has been proposed, and the use of wireless chargers rather than wired ones, which is cumbersome to use as a charging method for mobile devices, is gradually increasing.

The wireless charger for mobile devices can be divided into a magnetic induction (MI) method (ie, standard specification) and a magnetic resonance (MR) method (ie, standard specification), and two representative types of the magnetic induction method Examples of the method include a Wireless Power Consortium (WPC) method (ie, a standard standard) and a Power Matters Alliance (PMA) method (ie, a standard standard). On the other hand, in the case of a wireless charger, a contact surface of a certain area or more is required unlike a wire, and the contact surface is eventually implemented in the form of a pad. Accordingly, wireless charger pad products for mobile devices in which the upper plate is formed as a flat surface having a predetermined area are mainly produced.

The pad for wireless charger for mobile devices as described above can be used in various environments such as indoors, outdoors, and in vehicles. In particular, when installed in a vehicle, surface discoloration, whitening, etc. The product lifespan is reduced due to poor appearance, and as a result, consumer dissatisfaction is increasing.

Therefore, in the pad for wireless charger for mobile devices, through suitable additives considering the physical and chemical properties of synthetic rubber, which is the main material, it is possible to cause poor appearance such as surface discoloration and whitening due to oxidation within a short period of time when exposed to external ultraviolet rays, direct sunlight, and internal ozone. There is a need to develop a color rubber for a wireless charger pad that can be used semi-permanently to prevent it.

KR 10-2019-0017145 A (2019. 02. 20.)

The present invention has been devised to solve the problems of the prior art, and the problem to be solved in the present invention can be used in various environments such as indoors, outdoors, and in vehicles. The purpose of this is to provide a color rubber for wireless charger pad that prevents appearance defects such as surface discoloration and whitening caused by oxidation within a short period of time during ozone exposure and has an effect of preventing discoloration in a natural state that can be used semi-permanently.

The color rubber for a wireless charger pad having an effect of preventing discoloration in a natural state according to the present invention for achieving the above object includes synthetic rubber, paraffin oil, carbon black, sunscreen, anti-aging agent, and anti-rainbow agent. characterized.

In particular, based on 100 parts by weight of the synthetic rubber, 40 to 60 parts by weight of paraffinic oil, 10 to 30 parts by weight of carbon black, 5 to 15 parts by weight of sunscreen, 5 to 10 parts by weight of antioxidant, and 3 to 7 parts by weight of anti-rainbow agent. characterized by including.

In addition, as the synthetic rubber, ethylene-propylene rubber (EPDM) is used.

In addition, titanium dioxide (TiO ₂ ) is used as the sunscreen agent.

In addition, with respect to 100 parts by weight of synthetic rubber, a first mixing step of mixing 40-60 parts by weight of paraffin oil and 10-30 parts by weight of carbon black, and a sunscreen agent and anti-aging agent in the rubber mixture mixed in the first mixing step And a rainbow inhibitor mixed, with respect to 100 parts by weight of the synthetic rubber, a secondary mixing step of mixing 5 to 15 parts by weight of a sunscreen, 5 to 10 parts by weight of an anti-aging agent, and 3 to 7 parts by weight of an anti-rainbow agent, and the second Aging step of aging the rubber mixture mixed in the mixing step, a cutting step of cutting the rubber mixture aged in the aging step, and a molding vulcanizer for the rubber mixture cut in the cutting step at a pressure of 10 to 20 bar, 170 to 200 ℃ It characterized in that it comprises a molding step of molding by heating to a temperature of 3 to 5 minutes.

According to the present invention, it can be used in various environments such as indoors, outdoors, and vehicles through suitable additives in consideration of the physical and chemical properties of synthetic rubber. It prevents appearance defects such as surface discoloration and whitening, promotes user convenience, and can be used semi-permanently.

1 is a step flow chart showing a method of manufacturing a color rubber for a wireless charger pad having an effect of preventing discoloration in a natural state according to the present invention.

Hereinafter, the present invention will be described in detail.

The present invention can be used in various environments such as indoors, outdoors, and vehicles through suitable additives in consideration of the physical and chemical properties of rubber. In particular, when installed in a vehicle, the surface caused by oxidation within a short period of time when exposed to external ultraviolet rays, direct sunlight and internal ozone It relates to a color rubber for a wireless charger pad that prevents the occurrence of appearance defects such as discoloration and whitening, and has an effect of preventing discoloration in a natural state that can be used semi-permanently.

The color rubber for the wireless charger pad having the effect of preventing discoloration in the natural state according to the present invention comprises synthetic rubber, paraffin-based oil, carbon black, sunscreen, anti-aging agent and anti-rainbow agent.

More specifically, based on 100 parts by weight of the synthetic rubber, 40 to 60 parts by weight of paraffinic oil, 10 to 30 parts by weight of carbon black, 5 to 15 parts by weight of sunscreen, 5 to 10 parts by weight of antioxidant, and 3 to anti-rainbow agent 7 parts by weight.

The synthetic rubber is a component that is the main material of the color rubber for the wireless charger pad having the effect of preventing discoloration in the natural state according to the present invention, and includes ethylene-propylene rubber (EPDM), ethylene-propylene rubber (EPM), isoprene rubber (IR ), butadiene rubber (BR), 1,2-butadiene rubber, chloroprene rubber (CR), styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber (NBR), butyl rubber (IIR), ethylene-butene rubber ( EBM), chlorosulfonated polyethylene rubber (CSM), or a mixture of two or more may be used.

Among these, it is preferable to use ethylene-propylene rubber (EPDM) which is excellent in elasticity and excellent in heat resistance, cold resistance, material resistance, and chemical resistance.

Paraffin-based oil has excellent mechanical properties such as elongation, processability, heat resistance, and chemical resistance, and when mixed with synthetic rubber, it acts as a softener and has a stripe improvement effect.

The paraffinic oil has a weight average molecular weight of 600 to 900 g/mol, a kinematic viscosity of 100 to 200 cSt at 40 ° C., a specific gravity (15/4 ° C) of 0.75 to 0.95, a flash point of 250 to 300 ° C, and a pour point of - It may be 18 to -9 °C. When the weight average molecular weight, kinematic viscosity, specific gravity, and flash point of the paraffinic oil are within the above ranges, mixing with other compositions is made more easily.

If, with respect to 100 parts by weight of the synthetic rubber, when the paraffinic oil is mixed in less than 40 parts by weight, the paraffinic oil is not evenly mixed with the synthetic rubber, so it is difficult to have the above-mentioned effects sufficiently, and it is difficult to In the case of mixing, the overall physical properties may be rather deteriorated due to the amount of mixing more than necessary.

Carbon black increases oil resistance, abrasion resistance and heat resistance, and when mixed with synthetic rubber, it can perform various roles such as filler, reinforcing agent, and color improvement.

The carbon black may be of a particle type, and the particle size may be 0.01 to 5 μm. The above particle size has excellent tensile strength at high temperature.

If, based on 100 parts by weight of the synthetic rubber, less than 10 parts by weight of carbon black is mixed, it is difficult to sufficiently have the above-mentioned effects because the carbon black is not evenly mixed with the synthetic rubber, and it is mixed in excess of 30 parts by weight. In this case, the overall physical properties may be rather deteriorated due to the amount of mixing more than necessary.

In the present invention, titanium dioxide (TiO ₂ ) may be used as a sunscreen agent.

Since the titanium dioxide has accurate particle size and dispersibility, it has excellent hiding power and coloring power, and is used for pigments as well as chemically and physically very stable material. It is non-toxic, harmless to the environment and human body, and has high oxidizing power, so it can also remove odors, antibacterial and sterilize.

Therefore, when mixed with the synthetic rubber, which is the main material, it is possible to prevent appearance defects such as surface discoloration and whitening due to oxidation within a short period of time when exposed to external ultraviolet rays, direct sunlight, and internal ozone.

The titanium dioxide may have a particle size of 0.5 to 10 μm, and in the particle size range, dispersibility with synthetic rubber, which is the main material, is not reduced, and optimal effects and physical properties can be secured.

If, based on 100 parts by weight of the synthetic rubber, less than 5 parts by weight of the sunscreen agent is mixed, it is difficult to sufficiently have the above-mentioned effects because the sunscreen agent is not evenly mixed with the synthetic rubber, and it is mixed in excess of 15 parts by weight. In this case, the overall physical properties may be rather deteriorated due to the amount of mixing more than necessary.

The type of anti-aging agent is not particularly limited, and an anti-aging agent used in a known rubber composition can be appropriately used, and by mixing the antioxidant, it not only prevents the aging of synthetic rubber, which is the main material, but also acts as a UV-blocking agent. can be done

Preferably, one or a mixture of two or more of a phenol derivative, an aromatic amine derivative, an amine-ketone condensate, a benzimidazole derivative, a dithiocarbamic acid derivative, and a thiourea derivative may be used as the antioxidant.

Examples of the phenol derivative include styrenated phenol, 2,6-di-tert-butylphenol, 2,6-di-tert-butylcresol, 4,4'-butylidene-bis(3-methyl-6-tert- butylphenol), 4,4'-methylene-bis(2,6-di-tert-butylphenol), and 4,4'-thio-bis(6-tert-butyl-m-cresol) can be used.

Examples of the aromatic amine derivative include 4,4'-bis(α,α-dimethylbenzyl)diphenylamine, octylated diphenylamine, N,N′-diphenyl-p-phenylenediamine, and N,N′-diphenylamine. -2-naphthyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine can be used.

As the amine-ketone condensate, 2,2,4-trimethyl-1,2-dihydroquinoline polymer, 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, diphenylamine and A reactant of acetone may be used.

As the benzimidazole derivative, a zinc salt of 2-mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, or 2-mercaptobenzimidazole may be used.

As the dithiocarbamic acid derivative, nickel diethyldithiocarbamic acid and nickel dibutyldithiocarbamic acid may be used.

As the thiourea derivative, 1,3-bis(dimethylaminopropyl)-2-thiourea and tributylthiourea may be used.

If, with respect to 100 parts by weight of the synthetic rubber, when the antioxidant is mixed in less than 5 parts by weight, it is difficult to sufficiently have the above-mentioned effects because the antioxidant is not evenly mixed with the synthetic rubber, and it is mixed in excess of 10 parts by weight. In this case, the overall physical properties such as hardness, tensile strength, elongation, etc. may be reduced due to the amount of mixing more than necessary.

The type of the anti-rainbow agent is not particularly limited, and a rainbow-preventing agent used in a known rubber composition can be appropriately used. By mixing the anti-rainbow agent, oil discharge is suppressed and scratch resistance and adhesion are increased to prevent contamination. function can be performed.

Preferably, 30-50 parts by weight of dipentaerythritol hexaacrylate, 5-10 parts by weight of N-vinylpyrrolidone (NVA), 5-10 parts by weight of polyisocyanate based on 100 parts by weight of the polyfunctional acrylate monomer as a rainbow inhibitor It may be made by weight, including 1 to 2 parts by weight of the organometallic catalyst.

The polyfunctional acrylate monomer functions as a solvent to reduce viscosity to improve workability, improve surface smoothness to reduce rainbow generation, and improve transparency and scratch resistance.

Examples of the polyfunctional acrylate monomer include neopentyl glycol diacrylate, hexanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, ethoxylated trimethylolpropane triacrylate, and propylated trimethylolpropane. Triacrylate, glycerylpropylated triacrylate, tris(2-hydroxyethyl)isocyanurate triacrylate, pentaerythritol tetraacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol hydroxypentaacrylic Late, dipentaerythritol hexaacrylate, etc. can be used.

If, with respect to 100 parts by weight of the synthetic rubber, less than 3 parts by weight of the anti-rain agent is mixed, the anti-rain agent cannot be mixed evenly with the synthetic rubber, so it is difficult to sufficiently have the above-mentioned effects, and it is difficult to mix in excess of 7 parts by weight. In this case, the overall physical properties such as hardness, tensile strength, elongation, etc. may be reduced due to the amount of mixing more than necessary.

In the present invention, 5 to 10 parts by weight of additives may be further included with respect to 100 parts by weight of the synthetic rubber.

The additive may include a crosslinking agent, a separation aid, a lubricant, a heat stabilizer, a release agent, a weathering agent, a dispersing agent, and other additives.

The crosslinking agent causes a crosslinking reaction between rubber molecular chains to form a cured rubber, and includes 2,5-dimethyl-2,5-bis-(t-butylperoxy), dt-butylperoxide, 2,5- Dimethyl-2,5-bis-(t-butylperoxy)-hexane, t-butylcumylperoxide, bis-(t-butylperoxy-i-propyl)-benzene, dicumylperoxide, 4,4-di -t-butylperoxy-n-butylvalerate, t-butylperoxybenzoate, 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, benzoyl peroxide, bis-( 2,4-dichlorobenzoyl)-peroxide may be used alone or in combination.

As the separation aid, imidazole or imidazolyl may be used, and the separation aid alone or as a mixture with an alcohol such as water, methanol, ethanol, n-propanol, or an organic solvent such as toluene or xylene may be used in the composition. Its dispersibility can be increased.

Examples of the lubricant include hydrocarbon lubricants such as paraffin wax, polyolefin wax, and polypropylene wax obtained by refining crude oil; fatty acid amide lubricants such as steramide, oleamide, and erucamide; ester lubricants such as butyl stearate, glycerol monostearate, glycerine monooleate, stearyl stearate, and montan-based wax obtained by reacting montanic acid; stearic acid-based metal salt lubricants; fatty acid-based lubricants such as stearic acid and lauryl acid; Alternatively, an alcohol-based lubricant such as cetyl alcohol or stearyl alcohol may be used alone or in combination. In particular, polyethylene wax prepared by polymerization among polyolefin waxes, polypropylene wax polymerized with metallocene technology, and polyolefin wax prepared by reacting montanic acid are preferable, and more preferably, polyolefin wax produced by polymerization Polyethylene wax and montan-based polyolefin (Ployolefin) wax may be mixed and used.

As the thermal stabilizer, a phenol-based antioxidant, a HALS (Hindered Amine Light Stabilizer)-based antioxidant, or an amine-based antioxidant can be used alone or in combination. Preferably as a phenolic antioxidant, tetrakis [methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane (Tetrakis [methylene-3- (3,5- di-tert-butyl-4-hydroxyphenyl)propionate]methane), tris(3,4-di-tert-butyl-4-hydroxybenzyl)isocyanurate (Tris(3,4-di-tert-butyl- 4-hydroxybenzyl)isocyanurate), 1,3,5-trimethyl 2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene (1,3,5-trimrthyl 2,4 ,6-tris(3,5-di-tert-butyl-4-hydroxybenzl)benzene), 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butyl-phenol)butane (1 ,1,3-tris(2-methyl-4-hydroxy-5-tert-butyl-phenol)butane) can be used alone or in combination.

As the releasing agent, a fluorine-containing polymer, silicone oil, a metal salt of stearic acid, a metal salt of montanic acid, montanic acid ester wax, or polyethylene wax may be used.

As the weathering agent, a benzophenone-type or amine-type weathering agent may be used.

The dispersing agent functions to modify physical properties, and one or two or more of an ammonium salt, an active amine, an organic acid, and an inorganic acid may be used.

The other additives may be used alone or in combination with a metal deactivator, a phosphorus-based or sulfur-based antioxidant. Preferably, a mixture of a metal deactivator, a phosphorus antioxidant and a sulfur antioxidant is used.

In addition, the other additives may further include additives commonly used in the art. For example, antioxidants, neutralizing agents, nucleating agents, antistatic agents, slip agents, and the like. In addition, they may be included within an appropriate content range commonly used.

If, with respect to 100 parts by weight of the synthetic rubber, less than 5 parts by weight of the additive is included, it is difficult to expect the effect of each additive, and when it contains more than 10 parts by weight, the main characteristic due to the reduction of other components is synthesis. It is difficult to sufficiently expect the effects of rubber, paraffin oil, carbon black, and sunscreen.

1 is a step flow chart showing a method of manufacturing a color rubber for a wireless charger pad having an effect of preventing discoloration in a natural state according to the present invention.

1, the method for producing a color rubber for a wireless charger pad having an effect of preventing discoloration in a natural state according to the present invention is a primary mixing step (S10), a secondary mixing step (S20), an aging step ( S30), a cutting step (S40) and a forming step (S50) are included.

1. First mixing step (S10)

The first mixing step (S10) is a step of mixing synthetic rubber, paraffinic oil, and carbon black.

More specifically, with respect to 100 parts by weight of the synthetic rubber, 40 to 60 parts by weight of paraffinic oil and 10 to 30 parts by weight of carbon black are mixed.

In this case, as the synthetic rubber, ethylene-propylene rubber (EPDM) is used.

2. Second mixing step (S20)

The secondary mixing step (S20) is a step of mixing a sunscreen agent, an anti-aging agent and a rainbow inhibitor with the rubber mixture mixed in the first mixing step (S10).

More specifically, a sunscreen agent, an anti-aging agent and a rainbow inhibitor are mixed with the rubber mixture mixed in the first mixing step (S10), with respect to 100 parts by weight of the synthetic rubber, 5 to 15 parts by weight of the sunscreen, an anti-aging agent 5 to 10 parts by weight and 3 to 7 parts by weight of the anti-rainbow agent are mixed.

In this case, titanium dioxide (TiO ₂ ) is used as the sunscreen.

As the antioxidant, one or a mixture of two or more of a phenol derivative, an aromatic amine derivative, an amine-ketone condensate, a benzimidazole derivative, a dithiocarbamic acid derivative, and a thiourea derivative is used.

As the anti-rainbow agent, based on 100 parts by weight of the polyfunctional acrylate monomer, 30-50 parts by weight of dipentaerythritol hexaacrylate, 5-10 parts by weight of N-vinylpyrrolidone (NVA), 5-10 parts by weight of polyisocyanate, 1 to 2 parts by weight of the organometallic catalyst is mixed and used.

In addition, 5 to 10 parts by weight of additives may be further included with respect to 100 parts by weight of the synthetic rubber.

The additives include a crosslinking agent, a separation aid, a lubricant, a heat stabilizer, a release agent, a weathering agent, and a dispersing agent.

3. Aging stage (S30)

The aging step (S30) is a step of aging the rubber mixture mixed in the secondary mixing step (S20).

More specifically, the rubber mixture mixed in the second mixing step (S20) is aged for 10 to 15 hours in an aging room at a temperature of 15 to 25° C. and a humidity of 70% or less.

This is to increase the miscibility and dispersibility of the primary and secondary mixed rubber mixture.

4. Cutting step (S40)

The cutting step (S40) is a step of cutting the rubber mixture aged in the aging step (S30), and the rubber mixture aged in the aging step (S30) is cut to a thickness of 3 to 10 mm.

This is to facilitate the use of the aged rubber mixture in the pad for a wireless charger.

If the thickness of the aged rubber mixture is cut to be less than 3 mm, the shock absorption and heat transfer diffusion power are significantly reduced. will fall

5. Forming step (S50)

The molding step (S50) is a step of molding the rubber mixture cut in the cutting step (S40) by setting pressure, temperature, and time conditions in a molding vulcanizer.

More specifically, it is a step of molding the rubber mixture cut in the cutting step (S40) by heating it in a molding vulcanizer at a pressure of 10 to 20 bar and a temperature of 170 to 200° C. for 3 to 5 minutes.

This is derived as an optimal heating condition for heating the cut mixture to make the physical properties even, and at the same time, excellent in hardness, tensile strength and elongation.

If the molding vulcanizer is heated for less than 10 bar, 170° C., for less than 3 minutes, vulcanization by heating may not be sufficient and there may be a problem of deterioration of physical properties. Since the surface is overheated and the product itself is carbonized, there is a problem that the physical properties are lowered.

The color rubber for wireless charger pad, which has the effect of preventing discoloration in the natural state manufactured by the above method, can be used in various environments such as indoors, outdoors, and vehicles through suitable additives in consideration of the physical and chemical properties of synthetic rubber, especially in vehicles. When it is installed in an external UV light, direct sunlight and internal ozone exposure, it prevents appearance defects such as surface discoloration and whitening caused by oxidation within a short period of time, promotes user convenience, and can be used semi-permanently.

Hereinafter, the present invention will be described in more detail through examples. However, it is clear to those skilled in the art that the following examples are only for specifically illustrating the present invention, and do not limit the scope of the present invention. That is, simple modifications or changes of the present invention can be easily made by those skilled in the art, and all such modifications or changes can be considered to be included in the scope of the present invention.

Examples and Comparative Examples 1 to 3: Preparation of color rubber for wireless charger pad

The components are mixed according to the contents of Table 1 below, and aged for 12 hours in an aging room with a temperature of 20 ° C. and a humidity of 70% or less, and then the aged rubber mixture is cut to a thickness of 6 mm, and the cut rubber mixture is molded in a vulcanizer. It is manufactured by molding for 3 minutes at a pressure of 12.4 bar and a temperature of 185 °C.

Example

Comparative Example 1
Comparative Example 2
Comparative Example 3
synthetic rubber
(Ethylene-propylene rubber
(EPDM))

100 parts by weight
100 parts by weight
100 parts by weight
100 parts by weight
paraffinic oil

50 parts by weight
-
50 parts by weight
50 parts by weight
carbon black

20 parts by weight
20 parts by weight
20 parts by weight
20 parts by weight
sunscreen
(TiO2 ₂ )))

10 parts by weight
-
-
-
anti-aging agent

7 parts by weight
-
-
7 parts by weight
anti-rainbow

5 parts by weight
-
-
5 parts by weight
additive
(crosslinking agent, separation aid, lubricant, heat stabilizer, mold release agent, weathering agent, dispersant)


5 parts by weight

-

-


5 parts by weight

Experiment 1: Hardness, tensile strength, elongation, specific gravity measurement experiment

The hardness, tensile strength, elongation, and specific gravity of the colored rubber for the wireless charger pad prepared in Examples and Comparative Examples 1 to 3 were measured. Each was measured 4 times, and the average is shown in Table 2.

Example

Comparative Example 1
Comparative Example 2
Comparative Example 3
Hardness (HS)

60
57
57
60
Tensile strength (Kgf/㎠)

113.83
127
125
133.60
Elongation (%)

778.16
699
716

636.04
Specific gravity (g/cc)

1.168
1.145
1.167
1.145

As shown in Table 2, it can be seen that the results of the physical properties in the Examples did not change significantly, and satisfy the raw material testing standards MS269-03 and R610.

Experiment 2: Streak phenomenon and surface discoloration measurement experiment

The colored rubber for the wireless charger pad prepared in Examples and Comparative Examples 1 to 3 was stored in a sunny place indoors, and observed after 3 months to measure the stripe phenomenon and surface discoloration. The results are shown in Table 3 (◎ Excellent ○ Good △ Average × Poor).

Example

Comparative Example 1
Comparative Example 2
Comparative Example 3
stripe phenomenon

◎
×
○
◎
surface discoloration

◎
×
△
△

As shown in Table 3, it can be seen that the color rubber for the wireless charger pad of Examples included in the composition range of the present invention prevents both stripes and surface discoloration compared to Comparative Examples 1 to 3, thereby showing excellent appearance.

Claims (5)

With respect to 100 parts by weight of synthetic rubber,
40-60 parts by weight of paraffinic oil,
10-30 parts by weight of carbon black,
5-15 parts by weight of sunscreen,
5 to 10 parts by weight of an antioxidant and
Including 3 to 7 parts by weight of the anti-rainbow agent,
The synthetic rubber is
Ethylene-propylene rubber (EPDM) is used,
The carbon black uses a particle type, and the particle size is 0.01-5 μm,
The sunscreen is
Titanium dioxide (TiO ₂ ) is used, and the particle size is 0.5 to 10 μm,
One or a mixture of two or more of a phenol derivative, an aromatic amine derivative, an amine-ketone condensate, a benzimidazole derivative, a dithiocarbamic acid derivative, and a thiourea derivative is used as the antioxidant,
The anti-rainbow agent is based on 100 parts by weight of the polyfunctional acrylate monomer, 30-50 parts by weight of dipentaerythritol hexaacrylate, 5-10 parts by weight of N-vinylpyrrolidone (NVA), 5-10 parts by weight of polyisocyanate, Consists of 1 to 2 parts by weight of an organometallic catalyst,
5 to 10 parts by weight of additives based on 100 parts by weight of the synthetic rubber,
The additive is a color rubber for a wireless charger pad having a discoloration preventing effect in a natural state, characterized in that it includes a crosslinking agent, a separation aid, a lubricant, a heat stabilizer, a release agent, a weathering agent and a dispersing agent. delete delete delete delete

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