Method for using a silicone rubber paste without flow marks and color marks

Abstract

The application discloses a kind of silicon rubber color paste use methods without flow mark and color mark, including selecting color paste, pretreatment, metering, mixing, eccentric stirring, centering and taking paste, static mixing, paste mixing and forming step, by pretreatment step, most of the precipitate is filtered out, avoid color paste and silicon rubber after mixing, precipitation phenomenon occurs, thereby reducing the appearance of flow mark;By eccentric stirring step, the demand of mixing can be met while concentrating bubbles, the centering and taking paste step distinguishes the bubble-free mixed liquid and the mixed liquid containing bubbles, the static mixing step further mixes and defoams the mixed liquid containing bubbles, the elimination of bubbles can avoid the color mark phenomenon of product, by eccentric stirring, centering and taking paste and static mixing step, the original production efficiency can be maintained while solving the bubble problem, so as to prepare the silicon rubber product without flow mark and color mark.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of silicone rubber color paste, and particularly relates to a silicone rubber color paste use method without flow marks and color marks. BACKGROUND

[0002] When the silicone rubber color paste is used, the main reason for the flow marks is that the storage time of the color paste is too long, and a precipitation phenomenon exists, so that the viscosity of the color paste is not easy to control, the color paste is difficult to flow and disperse in the silicone rubber, and is easy to gather in a local area, thereby forming a color paste accumulation when the silicone rubber flows, so that the flow marks are generated; the color marks are mainly caused by unreasonable stirring, if the stirring speed is too slow or the stirring time is too short during the process of adding the color paste into the silicone rubber, the color paste cannot be uniformly dispersed in the silicone rubber matrix, which causes the generation of the flow marks and the color marks, and excessive stirring causes a large amount of air to be mixed in, thereby forming a large number of micro-bubbles, the micro-bubbles are left in the interior or surface of the silicone rubber after the color paste is mixed with the silicone rubber, and the micro-bubbles form voids when the silicone rubber is processed, thereby causing the point-shaped color marks. SUMMARY

[0003] In order to solve the above problems in the prior art, the application aims to provide a silicone rubber color paste use method without flow marks and color marks.

[0004] The technical scheme adopted by the application is as follows:

[0005] A silicone rubber color paste use method without flow marks and color marks comprises the following steps:

[0006] S1, selecting a color paste: selecting a suitable color paste according to the vulcanization temperature of the target silicone rubber and the temperature resistance of the color paste, to obtain color paste A;

[0007] S2, pretreatment: measuring the viscosity of the color paste A by using a rheometer, to obtain color paste A1 with qualified viscosity and color paste A2 with unqualified viscosity, repeatedly stirring and filtering the color paste A2 to obtain color paste A2' with qualified viscosity and waste, and mixing the color paste A1 and the color paste A2' to obtain color paste B;

[0008] S3, metering: determining the amount of the color paste B to be used according to the amount of the target silicone rubber by using an electronic balance, to obtain color paste B' and surplus material;

[0009] S4, mixing: adding the color paste B' to the target silicone rubber in batches, stirring after adding the color paste B' each time, and obtaining mixed liquid A after the color paste B' is completely added;

[0010] S5, eccentric stirring: the mixed liquid A is transferred to a container A, the container A is cylindrical, the bottom center O, there is a point P in the plane where the bottom of the container A is located, and the container A revolves around the vertical axis of point O while revolving around the vertical axis of point P;

[0011] S6, central slurry taking: the mixed liquid in the central region of the container A is taken out by using the container B to obtain the mixed liquid B1 in the central region and the mixed liquid B2 in the edge region;

[0012] S7, static mixing: the mixed liquid B2 is further mixed by using a static mixer to obtain the mixed liquid B2';

[0013] S8, slurry mixing: the mixed liquid B1 and the mixed liquid B2' are collected to obtain the mixed liquid C;

[0014] S9, molding: according to the silicone rubber molding process, the mixed liquid C is cured and molded to obtain a silicone rubber product without flow marks and color marks.

[0015] As a preferred embodiment of the present application, in the step S1, the selected color paste is one of organic pigment color paste and inorganic pigment color paste, the tolerance temperature H of the color paste is determined by the effective component of the color paste, the vulcanization temperature h of the target silicone rubber, and the selected color paste satisfies H-h>50℃.

[0016] As a preferred embodiment of the present application, in the step S2, the color paste A2' is the effective component of the filtered color paste A2, after stirring and filtering the color paste A2, the rheometer is used for retesting, if the viscosity meets the standard, the color paste A2' is obtained, if the viscosity does not meet the standard, stirring and filtering are performed again until the viscosity meets the standard.

[0017] As a preferred embodiment of the present application, in the step S3, the ratio of the target silicone rubber to the color paste B required by the finished product is measured by experiment, the color paste B is taken according to the ratio, and the remaining material is sealed.

[0018] As a preferred embodiment of the present application, in the step S4, the amount of the color paste B' added each time is 1 / 10 of the total amount, the stirring speed is 100-150 r / min, and the stirring time is 3-5 min.

[0019] As a preferred embodiment of the present application, in the step S5, the revolution and revolution of the container A are both periodic intermittent rotation, after 1-4 min of revolution, 5 s of interval, the revolution is performed in the interval time, the revolution angles are 180° / 45° / 180° / 45° / 180° / 45° / 180° / 45° in turn, the revolution is eight times for one period, the eccentric stirring step includes a complete revolution period, and the total stirring time is 8-32 min.

[0020] As preferred in the present application, in the step S6, the container A and the container B are both open at one end, the open end of the container A faces upward, the open end of the container B faces downward and is placed inside the container A, the container A and the container B keep coaxial, the mixed liquid A inside the container B is sucked by the negative pressure device, and the mixed liquid B1 is obtained.

[0021] As preferred in the present application, in the step S6, the distance between the bottom surface radius r1 of the container A, the center O and the fixed point P is L, the container B is cylindrical, the bottom surface radius r2 satisfies r1 < r2, r1 + r2 = L.

[0022] As preferred in the present application, in the step S7, the static mixer includes a plurality of mixing units, the mixed liquid B2 is divided by a plurality of the mixing units, the flow direction and speed are changed, and the mixed liquid B2' is obtained after re-converging.

[0023] As preferred in the present application, in the steps S8 and S9, the mixed liquid C is heated and kept warm before reaching the mold.

[0024] The present application has the following beneficial effects: as a method for using silicone rubber color paste without flow marks and color marks, the present application filters most of the precipitates through the pretreatment step, avoids the precipitation phenomenon after the color paste and the silicone rubber are mixed, and reduces the occurrence of flow marks; through the eccentric stirring step, the bubbles can be concentrated while meeting the mixing requirements, the mixed liquid without bubbles and the mixed liquid with bubbles are distinguished through the center taking paste step, the mixed liquid with bubbles is further mixed and defoamed through the static mixing step, the elimination of bubbles can avoid the color mark phenomenon of the product, through the eccentric stirring, center taking paste and static mixing steps, the bubble problem can be solved without reducing the original production efficiency, and thus the silicone rubber product without flow marks and color marks is prepared. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application is further described in detail below in combination with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application, that is, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments.

[0026] Therefore, the following detailed description of the embodiments of the present application is not intended to limit the scope of the claimed application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present application.

[0027] A method for using a silicone rubber color paste without flow marks and color marks, comprising the following steps:

[0028] S1, selecting a color paste: according to the vulcanization temperature h of the target silicone rubber and the tolerance temperature H of the color paste, selecting a suitable color paste, the selected color paste satisfies H-h>50℃, and a color paste A is obtained; the selected color paste is one of an organic pigment color paste and an inorganic pigment color paste, and the tolerance temperature H of the color paste is determined by the effective components of the color paste.

[0029] S2, pretreatment: measuring the viscosity of the color paste A by using a rheometer, obtaining a color paste A1 with qualified viscosity and a color paste A2 with unqualified viscosity, repeatedly stirring and filtering the color paste A2 to obtain a color paste A2' with qualified viscosity and waste, and mixing the color paste A1 and the color paste A2' to obtain a color paste B; the color paste A2' is the effective components of the color paste A2 after filtering, and after stirring and filtering the color paste A2, the viscosity is re-measured by using a rheometer, if the viscosity is qualified, the color paste A2' is obtained, if the viscosity is unqualified, stirring and filtering are performed again until the viscosity is qualified. In the subsequent stirring and filtering operation, the stirring time is increased, the mesh number of the filter screen is increased, the re-measurement is performed at least three times, and the waste after filtering is concentrated for treatment. The precipitate in the color paste can be effectively filtered out, and the generation of color marks is reduced.

[0030] S3, metering: using an electronic balance to determine the amount of the color paste B required to be used according to the amount of the target silicone rubber, obtaining a color paste B' and surplus material; the ratio of the target silicone rubber to the color paste B required for the finished product is measured by experiment, the color paste B is taken according to the ratio, and the surplus material is sealed. In the industrial silicone rubber molding process, the required silicone rubber and color paste are often in batches, and the surplus material of the previous batch can be used for the next batch production.

[0031] S4, mixing: the color paste B' is added to the target silicone rubber in batches, stirring is performed after each addition of the color paste B', the stirring speed is 100-150 r / min, the stirring time is 3-5 min, and after the color paste B' is completely added, a mixed liquid A is obtained; the amount of the color paste B' added each time is 1 / 10 of the total amount. Adding in batches can reduce the mixing difficulty to a certain extent and improve the mixing efficiency, and a certain amount of bubbles will inevitably be generated in this step in order to improve the mixing efficiency.

[0032] S5. Eccentric Stirring: The mixed liquid A is transferred to container A, which is cylindrical with a bottom center O. A fixed point P is located within the plane of the bottom surface of container A. Container A rotates on its own axis around the vertical axis of point O and revolves around the vertical axis of point P. The stirring time is 8-32 minutes. Both the rotation and revolution of container A are periodic and intermittent. After 1-4 minutes of revolution, there is a 5-second interval before rotating on its own axis. The rotation angles are 180° / 45° / 180° / 45° / 180° / 45° / 180° / 45°, with eight rotations constituting one cycle. The eccentric stirring step includes a complete rotation cycle. In this step, air bubbles in the mixed liquid are concentrated. Since the mass of air bubbles differs from that of the liquid, during the revolution, the air bubbles gradually approach the fixed point P. By adjusting the angle of container A through rotation, the air bubbles are distributed close to the inner wall of container A. A specially designed inner wall structure, such as a pleated structure, can effectively capture a large number of air bubbles. The 180° rotation angle is for reversal. Assuming that during a certain revolution, the closest point of container A to the fixed point P is m, and the farthest point is n, container A does not rotate during the revolution. Therefore, the bubbles in container A will approach point m, and after contacting the wrinkled inner wall of container A, they will be captured and will not easily escape. After a 180° rotation at intervals, the bubbles will approach point n in the next revolution and be captured. When the free bubbles in the mixed solution approach point n, the bubbles already captured at point m will not easily escape. The 45° rotation angle is to distribute the capture workload of the wrinkled inner wall. After multiple 45° rotations, the inner wall of container A can be evenly covered with bubbles.

[0033] S6. Central Slurry Extraction: Using container B, extract the mixed liquid from the central region of container A, obtaining mixed liquid B1 in the central region and mixed liquid B2 in the edge region. Both containers A and B are open at one end, with the open end of container A facing upwards and the open end of container B facing downwards, placed inside container A. Containers A and B are coaxial. A negative pressure device is used to siphon the mixed liquid A inside container B, obtaining mixed liquid B1. The base radius of container A is r1, and the distance between the center O and the fixed point P is L. Container B is cylindrical, with a base radius r2, satisfying r1 < r2 and r1 + r2 = L. After the above steps, the mixed liquid in the central region is free of air bubbles and can be used directly. According to the centrifugal force calculation formula, the larger the radius, the greater the centrifugal force. Therefore, when L is larger, the container A is farther away from the fixed point P, and the centrifugal force generated by the revolution is greater, so the bubbles can reach the edge of the container A faster. When r1 is constant, r2 can be increased by the above formula, so as to collect more mixed liquid B1. Conversely, when L decreases, the bubbles reach the edge of the container A more slowly. When r1 is constant, in order to avoid the container B collecting bubbles, r2 is decreased.

[0034] S7, static mixing: using a static mixer to further mix the mixed liquid B2, to obtain mixed liquid B2'; the static mixer includes a plurality of mixing units, the mixed liquid B2 is divided by a plurality of mixing units to change the flow direction and speed, and the mixed liquid B2' is obtained after reassembling. The mixed liquid in the edge area is further mixed and defoamed.

[0035] S8, slurry mixing: the mixed liquid B1 and the mixed liquid B2' are collected to obtain the mixed liquid C; the output speed of the mixed liquid B2' is different from that of the mixed liquid B1, and the mixed liquid B2' is intermittently outputted, and when there is no mixed liquid B2' outputted, the mixed liquid B1 can directly enter the next step alone.

[0036] S9, molding: according to the silicone rubber molding process, the mixed liquid C is cured and molded to obtain a silicone rubber product without flow marks and color marks. The mixed liquid C is heated and kept warm before reaching the mold.

[0037] Example one:

[0038] The main components of the silicone rubber are polysiloxane, dicumyl peroxide, silicon dioxide, kaolin and phthalate, and the vulcanization temperature is 120℃ by proportioning; the main components of the selected color paste are organic pigment (quinacridone, perylene pigment), silicone modified resin, polyether sulfone dispersant, zinc stearate and other heat stabilizers, which can maintain good performance at high temperature above 200℃.

[0039] The viscosity of the selected color paste is measured by a rheometer, compared with the standard viscosity value, and the color paste that does not meet the standard is stirred and filtered. If the retested color paste still does not meet the standard, it is stirred and filtered again until the viscosity of the color paste meets the standard.

[0040] Estimate the amount of color paste needed before viscosity test, and a part of it will be lost after test, stirring, filtering and retest; use an electronic balance to measure the ratio of silicone rubber and color paste needed for the finished product according to the amount of silicone rubber, take the color paste according to the proportion, and store the remaining material temporarily or seal it.

[0041] The color paste is added to the silicone rubber in 10 times, 1 / 10 each time, and stirring is carried out after each addition of color paste, with stirring speed of 100r / min and stirring time of 3min; the stirring speed is low to avoid a large amount of foaming of the mixed liquid.

[0042] After stirring, the mixed liquid is transferred to container A for eccentric stirring, which is divided into revolution and rotation. The stirring time is 8 minutes. After 1 minute of revolution, the interval is 5 seconds, and the rotation is performed during the interval. The rotation angles are 180° / 45° / 180° / 45° / 180° / 45° / 180° / 45°, and the rotation is performed eight times to complete the eccentric stirring. The speed of eccentric stirring is not particularly required. After eccentric stirring, the bubbles in the mixed liquid in the center region of container A will gather to the edge region. The inner wall of container A has a wrinkled structure, which can capture a large number of bubbles.

[0043] The mixed liquid in the center region of container A is taken out by using an inverted container B combined with a negative pressure suction device, and the mixed liquid in the center region and the mixed liquid with a large number of bubbles in the edge region are distinguished.

[0044] The mixed liquid in the edge region is collected, and the static mixer is used for further mixing of the mixed liquid in the edge region. When the mixed liquid passes through the static mixer, the mixing unit will divide the mixed liquid into several small streams. These small streams continuously change the flow direction and speed in the mixer, which promotes the further mixing of silicone rubber and color paste and eliminates a large number of bubbles contained therein. Considering that static mixing requires a large amount of time, a plurality of batches of mixed liquid in the edge region can be collected for one-time centralized processing to improve the efficiency of mixing and eliminating bubbles. The mixed liquid needs to be heated and kept warm during the collection process.

[0045] The mixed liquid obtained by the static mixer has the same performance as the mixed liquid in the center region of eccentric stirring, and can be mixed together for use or used separately. The mixed liquid obtained by eccentric stirring in the center region can be directly fed into the raw material bin, and the mixed liquid in the edge region of eccentric stirring can also be fed into the raw material bin after secondary mixing by the static mixer, and processed according to the silicone rubber forming process. The mixed liquid in the raw material bin is injected and solidified after forming to obtain a silicone rubber product.

[0046] After test detection, the obtained silicone rubber product has no flow marks and color marks.

[0047] Example Two:

[0048] The main components of silicone rubber are polysiloxane, dicumyl peroxide, silicon dioxide, kaolin, phthalate, and the vulcanization temperature is 120°C by proportioning; the main components of the selected color paste are organic pigment (quinacridone, perylene pigment), silicone modified resin, polyether sulfone dispersant, and zinc stearate, etc. heat stabilizer, which can maintain good performance at high temperature above 200°C.

[0049] The viscosity of the selected color paste is measured by using a rheometer, compared with the standard viscosity value, and the color paste that does not meet the standard is stirred and filtered. If the retested color paste still does not meet the standard, it is stirred and filtered again until the viscosity of the color paste meets the standard.

[0050] The amount of color paste used is estimated before the viscosity test, and a portion will be lost after the test, stirring, filtering and retesting; using an electronic balance, the ratio of silicone rubber to color paste required for the finished product is determined by experiment, and the color paste is taken according to the proportion, and the remaining material is temporarily stored or sealed.

[0051] The color paste is added to the silicone rubber in 10 times, 1 / 10 each time, and stirring is carried out after each addition of color paste, with a stirring speed of 150 r / min and a stirring time of 5 min; the stirring speed is low to avoid a large amount of foaming of the mixed liquid.

[0052] After stirring, the mixed liquid is transferred to container A for eccentric stirring, which is divided into revolution and rotation, with a total stirring time of 32 min; after 4 min of revolution, the rotation is performed at intervals of 5 s, with rotation angles of 180° / 45° / 180° / 45° / 180° / 45° / 180° / 45°, and the eccentric stirring is completed after eight rotations. The speed of eccentric stirring has no special requirements, and after eccentric stirring, the bubbles in the mixed liquid in the center region of container A will gather to the edge region, and the inner wall of container A has a wrinkled structure that can capture a large amount of bubbles.

[0053] The mixed liquid in the center region of container A is taken out using an inverted container B combined with a negative pressure suction device, and the mixed liquid in the center region and the mixed liquid with a large amount of bubbles in the edge region are distinguished.

[0054] The mixed liquid in the edge region is collected and further mixed using a static mixer. When the mixed liquid passes through the static mixer, the mixing unit will divide the mixed liquid into several small streams, which continuously change the flow direction and speed in the mixer, promoting the further mixing of silicone rubber and color paste while eliminating a large amount of bubbles contained therein. Considering that static mixing requires a lot of time, multiple batches of edge mixed liquid can be collected and processed at one time to improve the efficiency of mixing and bubble elimination. The mixed liquid needs to be heated and kept warm during collection.

[0055] The mixed liquid obtained by the static mixer has the same performance as the mixed liquid in the center region of eccentric stirring and can be mixed together for use or used separately. The mixed liquid in the center region of eccentric stirring can be directly fed into the raw material bin, and the mixed liquid in the edge region of eccentric stirring can also be added to the raw material bin after secondary mixing by the static mixer, and then processed according to the silicone rubber molding process. The mixed liquid in the raw material bin is injected and solidified to form a silicone rubber product.

[0056] After experimental detection, the obtained silicone rubber product has no flow marks and color marks.

[0057] Example three:

[0058] The main components of the silicone rubber are polysiloxane, dicumyl peroxide, silicon dioxide, kaolin, phthalate ester, and the vulcanization temperature is 120°C by proportioning; the main components of the selected color paste are organic pigments (quinacridone, perylene pigments), silicone-modified resin, polyether sulfone dispersant, and zinc stearate, etc. thermal stabilizers, which can maintain good performance at high temperatures above 200°C.

[0059] The viscosity of the selected color paste is measured by a rheometer, compared with the standard viscosity value, and the color paste that does not meet the standard is stirred and filtered. If the retest still does not meet the standard, it is stirred and filtered again until the viscosity of the color paste meets the standard.

[0060] Estimate the amount of color paste needed before viscosity testing. After testing, stirring, filtering and retesting, a portion will be lost; use an electronic balance to measure the amount of silicone rubber and color paste needed for the finished product according to the amount of silicone rubber used, and take the color paste in proportion, and the remaining material is temporarily stored or sealed.

[0061] Add the color paste to the silicone rubber in 10 times, 1 / 10 each time, and stir after each addition of color paste, stirring speed 120 r / min, stirring time 4 min; the stirring speed is low to avoid a large amount of foaming of the mixed liquid.

[0062] After stirring, transfer the mixed liquid to container A for eccentric stirring, which is divided into revolution and rotation, and the stirring time is 16 min in total; after 2 min of revolution, interval 5 s, execute rotation in the interval time, rotation angle 180° / 45° / 180° / 45° / 180° / 45° / 180° / 45°, and eccentric stirring is completed after eight rotations. The speed of eccentric stirring has no special requirements. After eccentric stirring, the bubbles in the mixed liquid in the center area of container A will gather to the edge area, and the inner wall of container A has a wrinkled structure that can capture a large amount of bubbles.

[0063] Use inverted container B to cooperate with negative pressure suction equipment to take out the mixed liquid in the center area of container A, and distinguish the mixed liquid in the center area from the mixed liquid with a large amount of bubbles in the edge area.

[0064] The edge mixed liquid is collected, the edge mixed liquid is further mixed by using a static mixer, when the mixed liquid passes through the static mixer, the mixing unit will divide the mixed liquid into several small streams, the small streams continuously change the flow direction and speed in the mixer, while promoting the further mixing of the silicone rubber and the color paste, eliminating a large number of air bubbles contained therein, considering that a large amount of time is required for static mixing, a plurality of batches of edge mixed liquids can be collected and then processed at one time to improve the mixing and air bubble elimination efficiency. The mixed liquid needs to be heated and kept warm during the collection process.

[0065] The mixed liquid obtained through the static mixer has the same performance as the mixed liquid in the eccentric stirring central region, and can be mixed together for use, or can be used alone. The mixed liquid obtained by the eccentric stirring central region can be directly fed into the raw material bin, and the mixed liquid obtained by the eccentric stirring edge region can also be added to the raw material bin after secondary mixing by the static mixer, and then processed according to the silicone rubber forming process. The mixed liquid in the raw material bin is injection molded and solidified to form a silicone rubber product.

[0066] Through experimental detection, the obtained silicone rubber product has no flow marks and color marks.

[0067] Comparative example:

[0068] The main components of the silicone rubber are polysiloxane, dicumyl peroxide, silicon dioxide, kaolin, phthalate, and the vulcanization temperature is 120°C by proportioning; the main components of the selected color paste are organic pigment (quinacridone, perylene pigment), silicone modified resin, polyether sulfone dispersant, zinc stearate and other heat stabilizers, which can maintain good performance at high temperature above 200°C.

[0069] After selecting the color paste, use an electronic balance to measure the ratio of silicone rubber to color paste required for the finished product according to the amount of silicone rubber used, take the color paste according to the proportion, and store the remaining material temporarily or seal it.

[0070] The color paste is added to the silicone rubber in 10 times, 1 / 10 each time, and stirring is carried out after each addition of the color paste, the stirring speed is 120 r / min, and the stirring time is 20 min (4 min + 16 min);

[0071] The obtained mixed liquid is added to the raw material bin, and then processed according to the silicone rubber forming process. The mixed liquid in the raw material bin is injection molded and solidified to form a silicone rubber product.

[0072] Through experimental detection, the obtained silicone rubber product has color marks and flow marks.

[0073] After comparing the products obtained by the above examples and the comparative example, the products of example one, example two and example three all have no obvious color marks and flow marks, and the product appearance is good; while the comparative example has a small amount of point color marks on the bottom of the product, and obvious longitudinal flow marks on the side of the product, and the overall appearance of the product is uneven in color and has defects.

[0074] In summary, the pretreatment step can filter out most of the precipitate, avoid the precipitation phenomenon after the color paste and silicone rubber are mixed, and thus reduce the occurrence of flow marks; the eccentric stirring step can concentrate the bubbles while meeting the mixing requirements; the center slurry taking step separates the mixed liquid without bubbles from the mixed liquid containing bubbles, the mixed liquid without bubbles can be directly used, and the mixed liquid containing bubbles is collected and treated separately; the mixed liquid without bubbles can meet the demand of high efficiency production; the static mixing step further mixes and defoams the mixed liquid containing bubbles, and the elimination of bubbles can avoid the color mark phenomenon of the product; the eccentric stirring, center slurry taking and static mixing steps of the present application can solve the bubble problem without reducing the original production efficiency, so as to prepare the silicone rubber product without flow marks and color marks.

[0075] The above content is only an example and description of the present application, and those skilled in the art can make various modifications or supplements or use similar ways to replace the described specific examples, as long as they do not deviate from the structure of the present application or exceed the scope defined by the claims of the present application, and all of them shall belong to the protection scope of the present application.

Claims

1. A method for using a silicone rubber colorant that produces no flow marks or color streaks, characterized in that, Includes the following steps: S1. Selecting the color paste: Based on the vulcanization temperature of the target silicone rubber and the temperature tolerance of the color paste, select a suitable color paste to obtain color paste A; S2. Pretreatment: The viscosity of the color paste A is measured using a rheometer to obtain color paste A1 with the viscosity meeting the standard and color paste A2 with the viscosity not meeting the standard. Color paste A2 is repeatedly stirred and filtered to obtain color paste A2' with the viscosity meeting the standard and waste material. Color paste A1 and color paste A2' are mixed to obtain color paste B. S3. Measurement: Using an electronic balance, determine the amount of pigment B to be used based on the amount of target silicone rubber, and obtain pigment B' and the remaining material; S4. Mixing: The color paste B' is added to the target silicone rubber in batches. Stirring is performed after each addition of the color paste B'. After all the color paste B' has been added, a mixed liquid A is obtained. S5. Eccentric stirring: The mixed liquid A is transferred to container A, which is cylindrical with a bottom center O. There is a fixed point P in the plane where the bottom surface of container A is located. Container A rotates around the vertical axis where point O is located while revolving around the vertical axis where the fixed point P is located. S6. Central sampling: Using container B, the mixed liquid in the central region of container A is extracted to obtain mixed liquid B1 in the central region and mixed liquid B2 in the edge region; S7. Static mixing: The mixed liquid B2 is further mixed using a static mixer to obtain mixed liquid B2'; S8. Mixing: The mixed liquid B1 and the mixed liquid B2' are combined to obtain mixed liquid C; S9. Molding: Processed according to the silicone rubber molding process, the mixed liquid C is cured and molded to obtain a silicone rubber product without flow marks and color marks; In step S5, the rotation and revolution of container A are both periodic intermittent rotations. After revolution for 1-4 minutes, there is a 5-second interval, during which rotation is performed. The rotation angles are 180° / 45° / 180° / 45° / 180° / 45° / 180° / 45°. Eight rotations constitute one cycle. The eccentric stirring step includes a complete rotation cycle, and the total stirring time is 8-32 minutes. In step S6, both container A and container B are open at one end, with the open end of container A facing upwards and the open end of container B facing downwards, and are placed inside container A. Container A and container B are kept coaxial, and the mixed liquid A inside container B is evacuated using a negative pressure device to obtain the mixed liquid B1; the inner wall of container A has a pleated structure.

2. The method for using a silicone rubber colorant without flow marks and color streaks according to claim 1, characterized in that: In step S1, the selected pigment paste is either an organic pigment paste or an inorganic pigment paste. The tolerance temperature H of the pigment paste is determined by the effective components of the pigment paste. The vulcanization temperature h of the target silicone rubber is such that the selected pigment paste satisfies Hh > 50℃.

3. The method for using a silicone rubber colorant without flow marks and color streaks according to claim 1, characterized in that: In step S2, the color paste A2' is the effective component after the color paste A2 is filtered. After the color paste A2 is stirred and filtered, it is retested using a rheometer. If the viscosity meets the standard, the color paste A2' is obtained. If the viscosity does not meet the standard, it is stirred and filtered again until the viscosity meets the standard.

4. The method for using a silicone rubber colorant without flow marks and color streaks according to claim 1, characterized in that: In step S3, the ratio of the target silicone rubber to the color paste B required for the finished product is determined by experiment. The color paste B is taken in proportion, and the remaining material is sealed.

5. The method for using a silicone rubber colorant without flow marks and color streaks according to claim 1, characterized in that: In step S4, the amount of pigment B' added each time is 1 / 10 of its total amount, the stirring speed is 100-150 r / min, and the stirring time is 3-5 min.

6. The method for using a silicone rubber colorant without flow marks and color streaks according to claim 1, characterized in that: In step S7, the static mixer includes multiple mixing units. The mixed liquid B2 is divided by the multiple mixing units, and its flow direction and speed are changed. After being collected again, the mixed liquid B2' is obtained.

7. The method for using a silicone rubber colorant without flow marks and color streaks according to claim 1, characterized in that: In steps S8 and S9, the mixed liquid C is heated and kept warm before it reaches the mold.