A soft, wear-resistant and easily printable silicone watch band and its preparation method

Abstract

The present application relates to the technical field of silicone watch bands, and in particular to a soft, wear-resistant and easy-to-print silicone watch band and a preparation method thereof. It is prepared from the following raw materials in parts by weight: 100 parts of base rubber, 5-15 parts of epoxy soybean oil, 2-8 parts of sodium silicate, 10-15 parts of color masterbatch, 1-2 parts of mold release agent, and 1-1.5 parts of vulcanizing agent. The base rubber is obtained by mixing polydimethylmethylvinylsiloxane and polymethylhydrosiloxane in a weight percentage of (50%-70%):(30%-50%). By using the above raw materials to prepare a soft, wear-resistant and easy-to-print silicone watch band, the surface activity of the silicone watch band is relatively high, making it easy to print text and patterns on the surface of the silicone watch band, and the text or patterns are not easily peeled off from the surface of the silicone watch band. At the same time, the skin-touch feeling of this silicone watch is relatively close to that of the human skin, with a good user experience. It has good wear resistance, high tensile strength and strong tear resistance.

Description

Technical Field

[0001] This application relates to the technical field of silicone watch straps, and particularly to a soft, wear-resistant and easy-to-print silicone watch strap and a preparation method thereof. Background Art

[0002] Silicone watch straps are one of the watch straps that people prefer to use now, and are made by pressing 100% pure natural solid silicone rubber with a hydraulic press. There are many colors in the existing silicone watch straps, and corresponding words or patterns need to be printed on the watch straps. However, because the silicone material belongs to an inert material with low surface activity, the adhesion of bonding, printing and other processing methods to it is poor. The printed layer on its surface is easy to fall off after long-term wear, affecting the aesthetic appearance of the silicone strap. In this regard, in order to solve the problem that the printed words or patterns are easy to fall off, after printing the words or patterns on the watch strap, a protective film is coated on its printed surface to solve the problem of the falling off of the words or patterns.

[0003] However, the protective film layer itself is also adhered to the silicone watch strap through a layer of glue. Therefore, when preparing the silicone watch strap, several additional processes are added, increasing the labor cost and time cost. In addition, the material of the protective film is different from that of the silicone watch strap, and its softness, skin-friendliness and wear resistance are far less than those of the silicone material, which will affect the use experience of the silicone watch strap, so it needs to be improved. Summary of the Invention

[0004] In order to improve the problem that the printed words or patterns on the existing silicone watch strap are easy to fall off, this application provides a soft, wear-resistant and easy-to-print silicone watch strap and a preparation method thereof.

[0005] In the first aspect, this application provides a soft, wear-resistant and easy-to-print silicone watch strap, adopting the following technical solution:

[0006] A soft, wear-resistant and easy-to-print silicone watch strap is prepared from the following raw materials in parts by weight:

[0007] Base rubber: 100 parts

[0008] Epoxidized soybean oil: 5 - 15 parts

[0009] Sodium silicate: 2 - 8 parts

[0010] Color masterbatch: 10 - 15 parts

[0011] Release agent: 1 - 2 parts

[0012] Vulcanizing agent: 1 - 1.5 parts

[0013] The base rubber is obtained by mixing polydimethylmethylvinylsiloxane and polymethylhydrosiloxane in a weight percentage of (50% - 70%):(30% - 50%).

[0014] By adopting the above technical solution, the silicone watch strap has good printability, softness and wear resistance. The surface activity of the silicone watch strap prepared from the base rubber, epoxy soybean oil, sodium silicate, masterbatch, mold release agent and vulcanizing agent is relatively high, and it is easy to print text and patterns on the surface of the silicone watch strap, so that the text or patterns are not easily detached from the surface of the silicone watch strap. Moreover, the skin-touch feeling of this silicone watch is quite close to that of the human skin, and the use experience is good. At the same time, the silicone watch strap prepared in this application has good wear resistance, tensile strength and tear resistance, and is not prone to hardening, cracking and poor skin-friendly feeling when used for a long time in relatively humid or hot and humid places.

[0015] In this application, by mixing epoxy soybean oil, sodium silicate and base rubber in a specific ratio to prepare the silicone watch strap, the surface activity of the silicone watch strap can be further improved, and the connection stability between the surface of the silicone watch strap and the printed text or pattern can be improved. At the same time, it can also improve the wear resistance, tensile strength and tear resistance of the silicone watch strap.

[0016] Preferably, the masterbatch is prepared by the following preparation method:

[0017] 1) Extruding and grinding the pigment, coupling agent and dispersant to obtain substance A;

[0018] 2) Co-grinding calcium carbonate and fiber until the average particle size reaches 200 - 300 nm, adding water and cationic surfactant, and continuing to grind until the average particle size reaches 20 - 30 nm to form a suspension;

[0019] 3) Mixing substance A, grafted starch and the suspension, heating to 70 - 80 °C, stirring for 3 - 4 h, drying, grinding, and grinding until the average particle size reaches 20 - 30 nm to obtain modified calcium carbonate powder;

[0020] 4) Mixing the modified calcium carbonate powder and low-density polyethylene, extruding and pelletizing to obtain the masterbatch.

[0021] By adopting the above technical solution, the watch strap has rich colors, and at the same time, the surface activity of the silicone watch strap is improved, so that the silicone watch strap can stably bond the printed text or pattern. The main function of the masterbatch is to uniformly disperse the pigment in the rubber product. The main components of the traditional masterbatch include pigment, carrier resin and dispersant. By fully kneading the pigment, carrier resin and dispersant, the dispersibility of the pigment can be improved. However, there are few reports on the stability of the printing performance of silicone products.

[0022] In this application, substance A is prepared by using a pigment, a coupling agent, and a dispersant. Then, a suspension is prepared by using calcium carbonate, fibers, a cationic surfactant, and water. Next, modified calcium carbonate powder is prepared by using substance A, grafted starch, and the suspension. Finally, a masterbatch is prepared by using the modified calcium carbonate powder and low-density polyethylene. When the masterbatch is used to prepare a soft, wear-resistant, and easily printable silicone watch band together with a base rubber, epoxy soybean oil, and sodium silicate, the bonding performance between the soft, wear-resistant, and easily printable silicone watch band and the ink can be improved, and the printed patterns or words can be effectively prevented from falling off.

[0023] In this application, calcium carbonate and fibers can be used to improve the connection stability between the silicone watch band and the printed words and patterns. During the experiment, it was found that when calcium carbonate and fibers were directly added to the silicone system, the high roughness of calcium carbonate and fibers would lead to poor hand feeling and softness of the silicone watch band, and the dispersibility of calcium carbonate and fibers was also poor. In contrast, in this application, the dispersibility of calcium carbonate and fibers is improved by grinding calcium carbonate, fibers, water, and a cationic surfactant. Grafted starch will improve the surface chemical inertness of the silicone watch band, enabling the printed patterns or words to be stably connected to the surface of the silicone watch band. At the same time, grafted starch will improve the problem of poor hand feeling of the silicone watch band caused by the high roughness of calcium carbonate and fibers themselves.

[0024] In this application, calcium carbonate, fibers, and grafted starch are involved in the preparation of the masterbatch. Utilizing the high dispersibility of the masterbatch, calcium carbonate, fibers, and grafted starch can be evenly dispersed into the silicone system, thereby optimizing the connection stability between the silicone watch band and the printed words and patterns, and improving the hand feeling and softness of the silicone watch band.

[0025] By grinding, the average particle size of calcium carbonate and fibers is reduced to 20 - 30 nm to improve the fineness of the silicone watch band and make it closer to the skin touch.

[0026] Preferably, the coupling agent is one of a silane coupling agent, a titanate coupling agent, a phosphate coupling agent, or a borate coupling agent.

[0027] Preferably, the dispersant includes at least one of polyethylene glycol, dodecyl acetic acid, white oil, pentanol, cellulose derivatives, polyacrylamide, guar gum, or fatty acid polyethylene glycol ester.

[0028] Preferably, the cationic surfactant is one of dodecyl trimethyl ammonium chloride, N-ethyl pyrrolidone, cetyl trimethyl ammonium bromide, tetradecyl trimethyl ammonium bromide, or octadecyl trimethyl ammonium chloride.

[0029] Preferably, in step 4), the temperature for extrusion granulation is 190 - 200 °C, and the pressure is 90 - 100 MPa.

[0030] Preferably, the weight parts of the raw materials used to prepare the masterbatch are as follows:

[0031] 4 - 9 parts of pigment

[0032] 2 - 3 parts of coupling agent

[0033] 1 - 2 parts of dispersant

[0034] 15 - 25 parts of calcium carbonate

[0035] 5 - 9 parts of fiber

[0036] 30 - 50 parts of water

[0037] 6 - 12 parts of cationic surfactant

[0038] 3 - 7 parts of grafted starch

[0039] 30 - 50 parts of low - density polyethylene.

[0040] By adopting the above - mentioned technical solution, the dosage of the raw materials for preparing the masterbatch is optimized, and the chemical inertness on the surface of the silica gel watch band is further reduced, so that the surface energy of the silica gel watch band can stably connect with the printed words or patterns and is not easily peeled off by external forces. In addition, by using the above - mentioned raw materials in combination, the dispersibility of the masterbatch can be improved. Using this masterbatch to prepare the silica gel watch band can improve the hand feeling of the silica gel watch band and make it closer to the skin feeling.

[0041] Preferably, the grafted starch is prepared by the following preparation method:

[0042] A: Mix starch and water, heat to 90 - 100 °C until it becomes transparent and viscous to obtain gelatinized starch;

[0043] B: Stir the gelatinized starch evenly with a sodium hydroxide solution with a mass fraction of 15 - 20%, ensure the reaction temperature is 50 - 60 °C, then add acrylic acid monomer and acrylamide monomer, stir evenly, then add an initiator, react for 2 - 3 h, add a citric acid solution to adjust the pH to 7.0 - 7.2, filter, take the filter residue, wash, and dry to obtain the grafted starch.

[0044] By adopting the above - mentioned technical solution, the grafted starch can further improve the problem that the high roughness of calcium carbonate and fiber themselves causes poor hand feeling of the silica gel watch band. In addition, by adding the grafted starch in this application, the connection stability between the silica gel watch band and the printed words and patterns can be further improved, and the skin - like feeling of the silica gel watch band is improved.

[0045] Preferably, the parts by weight of the raw materials used to prepare the grafted starch are as follows:

[0046] 10 - 15 parts of starch

[0047] 30 - 45 parts of water

[0048] 6 - 9 parts of sodium hydroxide solution with a mass fraction of 15 - 20%

[0049] 10 - 15 parts of acrylic monomer

[0050] 5 - 20 parts of acrylamide monomer

[0051] 1 - 2 parts of initiator

[0052] 5 - 9 parts of citric acid solution.

[0053] By adopting the above - mentioned technical solution, the dosage of the raw materials for preparing the grafted starch is optimized, and the properties of the starch are changed, thereby further improving the skin - friendly feeling of the silicone watch band and the connection stability with printed words and patterns, and at the same time increasing the grafting rate of the starch.

[0054] Preferably, the acrylic monomer includes at least one of acrylic acid, methacrylic acid, maleic acid or itaconic acid.

[0055] The initiator is one of benzoyl peroxide, ammonium persulfate or ammonium cerium nitrate.

[0056] Preferably, the starch is at least one of potato starch, cassava starch, corn starch, sweet potato starch, pea starch, wheat starch, mung bean starch or lotus root starch.

[0057] By adopting the above - mentioned technical solution, the grafting rate of the grafted starch is increased. At the same time, the smoothness of the surface of the silicone watch band is further improved, making it closer to the skin feeling and improving the use comfort.

[0058] Preferably, the release agent is at least one of dimethyl silicone oil, methyl tolyl silicone oil or diethyl silicone oil.

[0059] By adopting the above - mentioned technical solution, the prepared soft, wear - resistant and easy - to - print silicone watch band has excellent demoulding property, smooth product surface and no pollution.

[0060] Preferably, the epoxy value of the epoxy soybean oil is 5.5 - 15 eq / 100g, and the acid value is 0.5 - 1.2 mgKOH / g.

[0061] By adopting the above - mentioned technical solution, the parameters of the epoxy soybean oil are optimized, so that the activity of the surface of the silicone watch band is increased, which is beneficial to enhancing the connection stability of the words and patterns printed on the surface of the silicone watch band. At the same time, the wear - resistant performance, tensile strength and tear - resistance performance of the silicone watch band are further improved.

[0062] Preferably, the content of vinyl in the polydimethylmethylvinylsiloxane is 1% - 5%, and the molecular weight is 5000 - 20000; the molecular weight of the polymethylhydrosiloxane is 2000 - 4000.

[0063] By adopting the above technical solution, the parameters of polydimethylmethylvinylsiloxane and polymethylhydrosiloxane are optimized to further improve the wear resistance, tensile strength and tear resistance of the silicone watch strap.

[0064] In a second aspect, the present application provides a method for preparing a soft, wear-resistant and easily printable silicone watch strap, adopting the following technical solution:

[0065] A method for preparing a soft, wear-resistant and easily printable silicone watch strap includes the following preparation steps:

[0066] S1. According to parts by weight, mix the base rubber, color masterbatch, epoxy soybean oil, sodium silicate, mold release agent and vulcanizing agent to obtain a mixed rubber.

[0067] S2. Then put the mixed rubber into a mold, and under the conditions of a temperature of 180 - 200 °C, a pressure of 11 - 13 MPa, and a vulcanization time of 10 - 20 min, form it to obtain a soft and wear-resistant silicone watch strap.

[0068] By adopting the above technical solution, the prepared soft and wear-resistant silicone watch strap has a comfortable feel, is closer to the skin feel, and the characters or patterns printed on its surface can be stably preserved, and it has good wear resistance, tensile strength and tear resistance.

[0069] In summary, the present application has the following beneficial effects:

[0070] 1. In the present application, by preparing a soft, wear-resistant and easily printable silicone watch strap from the base rubber, epoxy soybean oil, sodium silicate, color masterbatch, mold release agent and vulcanizing agent, the chemical activity on the surface of the silicone watch strap is improved, making it easier to combine with the printed characters or patterns and not easily falling off during use. At the same time, by using the above raw materials in a specific proportion, the wear resistance, tensile strength and tear resistance of the rubber watch strap can be further improved, and it is not easy to show the situation of the watch strap becoming hard, cracking and having a poor skin-friendly feel when used in relatively humid or hot and humid places for a long time.

[0071] 2. In the present application, by preparing substance A from pigments, coupling agents and dispersants, then preparing a suspension from calcium carbonate, fibers, cationic surfactants and water, then preparing modified calcium carbonate powder from substance A, grafted starch and the suspension, and then preparing a color masterbatch from the modified calcium carbonate powder and low-density polyethylene, when the color masterbatch is used together with the base rubber, epoxy soybean oil and sodium silicate to prepare a soft, wear-resistant and easily printable silicone watch strap, the bonding performance between the soft, wear-resistant and easily printable silicone watch strap and the ink can be improved, effectively preventing the printed patterns or characters from falling off. Detailed Embodiments

[0072] Examples

[0073] Example 1

[0074] A soft, wear-resistant and easy-to-print silicone watch band is prepared by the following preparation method:

[0075] S1. Knead 1000.00 g of base rubber, 100.00 g of masterbatch, epoxy soybean oil, 20.00 g of sodium silicate, 10.00 g of release agent (dimethyl silicone oil), and 10.00 g of vulcanizing agent (benzoyl peroxide) to obtain a kneaded rubber.

[0076] S2. Then put the kneaded rubber into a mold, and under the conditions of a temperature of 180 °C and a pressure of 11 MPa, the vulcanization time is 10 min to form a soft, wear-resistant and easy-to-print silicone watch band.

[0077] The base rubber is obtained by mixing polydimethylmethylvinylsiloxane and polymethylhydrosiloxane in a weight percentage of 50%:50%. The polydimethylmethylvinylsiloxane is 500.00 g, and the polymethylhydrosiloxane is 500.00 g.

[0078] The content of vinyl in polydimethylmethylvinylsiloxane is 0.2%, and the molecular weight is 5000; the molecular weight of polymethylhydrosiloxane is 2000.

[0079] The masterbatch is obtained by fully kneading 40.00 g of pigment, 300.00 g of carrier resin (PET), and 10.00 g of dispersant (polyethylene glycol) and granulating.

[0080] The epoxy value of epoxy soybean oil is 5.5 eq / 100 g, and the acid value is 0.5 mgKOH / g.

[0081] The differences between Example 2-3 and Example 1 are that the types, dosages of some raw materials and test parameters for preparing the soft and wear-resistant silicone watch band are different. The specific differences are shown in Table 1:

[0082] Table 1 Types, dosages of raw materials and test parameters for preparing the soft and wear-resistant silicone watch band in Examples 1-3

[0083]

[0084]

[0085] Example 4

[0086] A soft, wear-resistant and easy-to-print silicone watch band. The difference between this example and Example 1 is that the masterbatch is prepared by the following method:

[0087] 1) Extrude and grind 40.00 g of pigment, 20.00 g of coupling agent (vinyltris(β-methoxyethoxy)silane), and 10.00 g of dispersant (polyethylene glycol) to obtain Substance A;

[0088] 2) Grind 150.00 g of calcium carbonate and 50.00 g of fiber together. First, grind until the average particle size reaches 200 nm. Then add 300.00 g of water and 60.00 g of a cationic surfactant (dodecyl trimethyl ammonium chloride), and continue grinding until the average particle size is 20 nm to prepare a suspension.

[0089] 3) Mix substance A, 30.00 g of grafted starch, and the suspension. Heat to 70 °C, stir for 3 h, dry, and grind until the average particle size is 20 nm to obtain modified calcium carbonate powder.

[0090] 4) Mix the modified calcium carbonate powder with 300.00 g of low-density polyethylene, and extrude and pelletize to obtain a masterbatch.

[0091] The temperature for extrusion and pelletization is 190 °C, and the pressure is 90 MPa.

[0092] The grafted starch is acrylic acid-grafted starch with a grafting rate of 3%.

[0093] The molecular weight of the low-density polyethylene is 20,000.

[0094] The differences between Examples 5 - 6 and Example 4 are that the types, amounts of some raw materials for preparing the masterbatch, and test parameters are different. The specific differences are shown in Table 2:

[0095] Table 2 Types, amounts of raw materials for preparing the masterbatch in Examples 4 - 6, and test parameters

[0096]

[0097]

[0098] Example 7

[0099] A soft, wear-resistant, and easy-to-print silicone watch band. The difference between this example and Example 4 is that the grafted starch is prepared by the following method:

[0100] A: Mix 100.00 g of starch (corn starch) and 300.00 g of water, and heat to 90 °C until it becomes transparent and viscous to obtain gelatinized starch.

[0101] B: Stir the gelatinized starch evenly with 60.00 g of a 15% sodium hydroxide solution, ensure the reaction temperature is 50 °C, then add 100.00 g of acrylic acid monomer (acrylic acid) and 50.00 g of acrylamide monomer, stir evenly, then add 10.00 g of initiator, react for 2 h, add 50.00 g of a 15% citric acid solution to adjust the pH to 7.0, filter, take the filter residue, wash, and dry to obtain the grafted starch.

[0102] Examples 8-9 are different from Example 7 in that the types, dosages of some raw materials for preparing the grafted starch and the test parameters are different. The specific differences are shown in Table 3:

[0103] Table 3 Types, dosages of raw materials and test parameters for preparing grafted starch in Examples 7-9

[0104]

[0105] Example 10

[0106] A soft, wear-resistant and easy-to-print silicone watch band. This example is different from Example 7 in that when preparing the grafted starch, water is used to replace an equal amount of acrylamide monomer, and the types, dosages of the remaining raw materials and the experimental parameters are the same as those in Example 7.

[0107] Example 11

[0108] A soft, wear-resistant and easy-to-print silicone watch band. This example is different from Example 7 in that when preparing the grafted starch, water is used to replace an equal amount of acrylic acid monomer, and the types, dosages of the remaining raw materials and the experimental parameters are the same as those in Example 7.

[0109] Example 12

[0110] A soft, wear-resistant and easy-to-print silicone watch band. This example is different from Example 1 in that the epoxy value of the epoxy soybean oil is 2.0 eq / 100g and the acid value is 0.5 mgKOH / g, and the types, dosages of the remaining raw materials and the experimental parameters are the same as those in Example 1.

[0111] Example 13

[0112] A soft, wear-resistant and easy-to-print silicone watch band. This example is different from Example 1 in that the epoxy value of the epoxy soybean oil is 2.5 eq / 100g and the acid value is 1.4 mgKOH / g, and the types, dosages of the remaining raw materials and the experimental parameters are the same as those in Example 1.

[0113] Example 14

[0114] A soft, wear-resistant and easy-to-print silicone watch band. This example is different from Example 4 in that when preparing the masterbatch, the grafted starch is replaced with an equal amount of starch, and the types, dosages of the remaining raw materials and the experimental parameters are the same as those in Example 4.

[0115] Example 15

[0116] A soft, wear-resistant and easy-to-print silicone watch band. This example is different from Example 4 in that when preparing the masterbatch, the fiber is replaced with an equal amount of water, and the types, dosages of the remaining raw materials and the experimental parameters are the same as those in Example 4.

[0117] Comparative Example

[0118] Comparative Example 1

[0119] A silicone watch band. The difference between this example and Example 1 is that grape seed oil is used to replace an equal amount of epoxy soybean oil, and the types, dosages of the remaining raw materials, and experimental parameters are all the same as those in Example 1.

[0120] Comparative Example 2

[0121] A silicone watch. The difference from Example 1 is that grape seed oil is used to replace an equal amount of polymethylhydrogensiloxane, and the types, dosages of the remaining raw materials, and experimental parameters are all the same as those in Example 1.

[0122] Comparative Example 3

[0123] A silicone watch band. The difference between this example and Example 1 is that grape seed oil is used to replace an equal amount of polydimethylmethylvinylsiloxane, and the types, dosages of the remaining raw materials, and experimental parameters are all the same as those in Example 1.

[0124] Comparative Example 4

[0125] A silicone watch band. The difference between this example and Example 1 is that silica is used to replace an equal amount of sodium silicate, and the types, dosages of the remaining raw materials, and experimental parameters are all the same as those in Example 1.

[0126] Performance Detection Test

[0127] The soft, wear-resistant, and easy-to-print silicone watch bands prepared in Examples 1 - 15 and Comparative Examples 1 - 4 were subjected to peeling tests, wear resistance tests, tensile strength tests, and tear strength tests.

[0128] Detection Method / Test Method

[0129] The soft and wear-resistant silicone watch bands prepared in Examples 1 - 15 and the silicone watch bands prepared in Comparative Examples 1 - 4 were printed to obtain words and patterns.

[0130] Peeling Test: Place the side with words and patterns of the soft and wear-resistant silicone watch bands prepared in Examples 1 - 15 and the silicone watch bands prepared in Comparative Examples 1 - 4 on a flat surface, attach 3M tape to the surface of the words or patterns, then place a 100g medium weight on its surface, let it stand for 30 min, and then tear off the tape to observe whether the words and patterns fall off.

[0131] Abrasion resistance test: The test was carried out using an ABER abrasion testing machine for leather and leather goods, model DB-523, with a load of 500 g and the number of revolutions set to 2000. The side with printed text and patterns of the soft and abrasion-resistant silicone watch straps prepared in Examples 1-15 and the silicone watch straps prepared in Comparative Examples 1-4 was placed on a plane in contact with the grinding head for testing. After the test, observe whether the printed text and patterns on the surface of the silicone watch strap are damaged.

[0132] Tensile strength: According to GB / T528-2009 "Rubber, vulcanized or thermoplastic - Determination of tensile stress - strain properties", the tensile strength and elongation at break of the test specimens were tested.

[0133] Tear strength: The test was carried out according to GB / T529-2008 "Rubber, vulcanized or thermoplastic - Determination of tear strength (trouser, right - angled and crescent - shaped specimens)". The experimental data are shown in Table 4:

[0134] Experimental data in Examples 1-15 and Comparative Examples 1-4

[0135]

[0136]

[0137] It can be seen from Examples 1-15 and Comparative Examples 1-4 combined with Table 4 that the soft, abrasion - resistant and easily printable silicone watch straps prepared by this application have good fixing effects on the printed text and patterns after printing, and have good abrasion resistance, tensile strength and tear strength.

[0138] By comparing Example 1 with Comparative Example 1, it shows that by using epoxy soybean oil, the stability of the text or printed pattern printed on the surface of the soft, abrasion - resistant and easily printable silicone watch strap can be further improved, it is not easy to fall off during its use, and the tensile strength and tear strength of the soft, abrasion - resistant and easily printable silicone watch strap are better.

[0139] By comparing Example 1 with Comparative Example 2, and Example 1 with Comparative Example 3, it shows that by using polydimethylmethylvinylsiloxane and polymethylhydrosiloxane together, the stability of the printed pattern or text on the soft, abrasion - resistant and easily printable silicone watch strap after printing can be further improved, and at the same time, the tensile strength and tear strength of the soft, abrasion - resistant and easily printable silicone watch strap can also be improved.

[0140] By comparing Example 1 with Comparative Example 4, it shows that by using sodium silicate, the stability of the text or printed pattern printed on the surface of the soft, abrasion - resistant and easily printable silicone watch strap can be further improved, and it is not easy to fall off during its use.

[0141] Comparing Example 1 with Example 4, Example 7 with Example 14, and Example 7 with Example 15, it shows that the masterbatch prepared in this application, when used to prepare a soft, wear-resistant and easy-to-print silicone watch band, can improve its friction resistance.

[0142] Comparing Example 4 with Example 7, Example 7 with Example 10, and Example 7 with Example 11, it shows that the grafted starch prepared in this application, when used to prepare a masterbatch and then used to prepare a soft, wear-resistant and easy-to-print silicone watch band, can improve its tensile strength and tear strength.

[0143] This specific embodiment is only an interpretation of this application and does not limit this application. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions as needed, but as long as it is within the scope of the claims of this application, it is protected by the patent law.

Claims

1. A soft, wear-resistant and easy-to-print silicone watch band, characterized in that: Prepared from the following raw materials in parts by weight: Base rubber: 100 parts Epoxidized soybean oil: 5 - 15 parts Sodium silicate: 2 - 8 parts Color masterbatch: 10 - 15 parts Release agent: 1 - 2 parts Vulcanizing agent: 1 - 1.5 parts The base rubber is obtained by mixing polydimethylmethylvinylsiloxane and polymethylhydrosiloxane in a weight percentage of (50% - 70%):(30% - 50%); The color masterbatch is prepared by the following preparation method: 1) Extruding and grinding the pigment, coupling agent and dispersant to obtain substance A; 2) Co-grinding calcium carbonate and fiber until the average particle size is 200 - 300 nm, adding water and cationic surfactant, and continuing to grind until the average particle size is 20 - 30 nm to form a suspension; 3) Mixing substance A, grafted starch and the suspension, heating to 70 - 80 °C, stirring for 3 - 4 h, drying and grinding until the average particle size is 20 - 30 nm to obtain modified calcium carbonate powder; 4) Mixing the modified calcium carbonate powder and low-density polyethylene, extruding and pelletizing to obtain the color masterbatch; The parts by weight of the raw materials used to prepare the color masterbatch are as follows: Pigment: 4 - 9 parts Coupling agent: 2 - 3 parts Dispersant: 1 - 2 parts Calcium carbonate: 15 - 25 parts Fiber: 5 - 9 parts Water: 30 - 50 parts Cationic surfactant: 6 - 12 parts Grafted starch: 3 - 7 parts Low-density polyethylene: 30 - 50 parts; The grafted starch is prepared by the following preparation method: A: Mixing starch and water, heating to 90 - 100 °C until it becomes transparent and viscous to obtain gelatinized starch; B: Stirring the gelatinized starch evenly with a sodium hydroxide solution with a mass fraction of 15% - 20%, ensuring the reaction temperature is 50 - 60 °C, then adding acrylic acid monomer and acrylamide monomer, stirring evenly, adding an initiator, reacting for 2 - 3 h, adding a citric acid solution to adjust the pH to 7.0 - 7.2, filtering, taking the filter residue, rinsing and drying to obtain the grafted starch; The parts by weight of the raw materials used to prepare the grafted starch are as follows: Starch: 10 - 15 parts Water: 30 - 45 parts Sodium hydroxide solution with a mass fraction of 15% - 20%: 6 - 9 parts Acrylic acid monomer: 10 - 15 parts Acrylamide monomer: 5 - 20 parts Initiator: 1 - 2 parts Citric acid solution: 5 - 9 parts.

2. The soft, wear-resistant and easy-to-print silicone watch band according to claim 1, characterized in that: The starch is at least one of potato starch, tapioca starch, corn starch, sweet potato starch, pea starch, wheat starch, mung bean starch or lotus root starch.

3. A soft, wear-resistant and easy-to-print silicone watch band according to claim 1, characterized in that: The release agent is at least one of dimethyl silicone oil, methyl tolyl silicone oil or diethyl silicone oil.

4. A soft, wear-resistant and easy-to-print silicone watch band according to claim 1, characterized in that: The epoxy value of the epoxidized soybean oil is 5.5 - 15 eq / 100 g, and the acid value is 0.5 - 1.2 mgKOH / g.

5. A soft, wear-resistant and easy-to-print silicone watch band according to claim 1, characterized in that: The content of vinyl in the polydimethylmethylvinylsiloxane is 1% - 5%, and the molecular weight is 5000 - 20000; the molecular weight of the polymethylhydrosiloxane is 2000 - 4000.

6. A preparation method of a soft and wear-resistant silicone watch band according to any one of claims 1-5, characterized in that, Including the following preparation steps: S1. Mixing the base rubber, color masterbatch, epoxidized soybean oil, sodium silicate, release agent and vulcanizing agent by weight to obtain a mixed rubber; S2. Then put the mixed rubber into a mold, and under the conditions of a temperature of 180 - 200 °C, a pressure of 11 - 13 MPa, and a vulcanization time of 10 - 20 min, carry out molding to obtain a soft, wear-resistant and easy-to-print silicone watch band.

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