Manufacturing method of silica gel bag PP product suitable for infants and children

Abstract

The invention relates to a production method of a silica gel bag PP product suitable for infants and children, which is characterized by comprising the following steps: A, preparing PP, POE and PA materials, firstly heating PP to a liquid state, then adding POE, raising the temperature, mixing the PP and the POE in the liquid state, then adding PA, continuing heating, mixing the PP, the POE and the PA in the liquid state, mixing the PP, the POE and the PA in the liquid state with raw materials, performing wire drawing through a plastic wire drawing machine, and finally cutting into particles; b, putting the granules into a plastic injection molding machine to obtain a plastic semi-finished product, and putting the plastic semi-finished product into a plasma machine; c, the surface of the plastic is coated with an adhesive, and the plastic is placed in an oven to be baked; d, after cooling, baking in an oven, then putting into a mold cavity of an injection molding machine, and adding LSR silica gel into the injection molding machine to obtain a product; and E, putting the product into a plasma machine for surface treatment after mold stripping to obtain a final product. Compared with a pure silica gel product, the process is simple, and the production cost is low.

Description

[Technical field]

[0001] The invention relates to a method for manufacturing a silica gel-coated PP product. [Background technology]

[0002] The materials used in baby products such as baby bottles, nipples, and breast pumps must be food-safe. Common materials include PP, PPSU, and silicone, which are widely used materials. These materials have certain advantages. PP (polypropylene) has the advantages of being light, drop-resistant, easy to clean, and inexpensive, but has poor toughness and is easily scratched; PPSU (polyphenylene sulfone resin), PPSU baby bottles, also known as polyphenylsulfone baby bottles, have the advantages of high temperature resistance, corrosion resistance, radiation resistance, and wear resistance, but are relatively expensive; liquid silicone (LSR) has good heat resistance, oxidation resistance, and corrosion resistance, is not easy to deform, is easy to clean, is relatively expensive, and has poor connection performance. Due to the characteristics of the three materials, from a safety perspective, baby bottles use more PPSU, and nipples use more silicone, but the prices of these two are relatively expensive, and PP is also relatively light and durable, especially at a low price, and also has a certain market. If PP can be combined with silicone, the product will be more competitive, and how to more firmly encapsulate PP and silicone is the key point to be solved in this case. [Summary of the invention]

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method for producing a silica gel package PP product suitable for infants and children with low production cost.

[0004] In order to solve the above problems, the present invention adopts the following technical solutions:

[0005] A method for producing a silica gel-coated PP product suitable for infants and children, characterized by comprising the following steps:

[0006] A. Prepare PP, POE and PA materials. First, heat PP to liquid state, then add POE and increase the temperature to mix PP and POE in liquid state, then add PA and continue to heat to mix PP, POE and PA in liquid state. Then, draw the mixed raw materials of PP, POE and PA in liquid state through a plastic drawing machine and finally cut them into particles.

[0007] B. Put the above granular material into a plastic injection molding machine, heat it until it melts, and inject it into the mold cavity of the injection molding machine to obtain a plastic semi-finished product. Put the plastic semi-finished product into a plasma machine to attach ions to the surface of the plastic semi-finished product;

[0008] C. Apply special adhesive on the plastic surface and bake it in the oven for 20-50 minutes at a temperature of 100-110°C;

[0009] D. After cooling, the plastic semi-finished product coated with the special adhesive is placed in an oven for baking, and then placed in the mold cavity of an injection molding machine. LSR silicone is added to the injection molding machine, and the temperature of the LSR silicone is controlled between 140°C and 145°C. After vulcanization for 180 seconds to 200 seconds, the LSR silicone is injected into the mold cavity so that the LSR silicone is wrapped around the edge of the plastic semi-finished product, and the product is removed from the mold after the silicone is wrapped.

[0010] E. After the mold is finished, the product is placed in a plasma machine for surface treatment to obtain the final product.

[0011] The method for producing a silicone-coated PP product suitable for infants and children as described above is characterized in that the weight proportions of PP, POE and PA in step A are 80%, 10% and 10% respectively.

[0012] As described above, a method for producing a silica gel package PP product suitable for infants and children is characterized in that the heating temperature in step APP is 220°C, the heating temperature in POE is 240°C, the heating temperature in PA is 260°C, and the heating temperature in step B of the granular material is 260°C.

[0013] The method for producing a silicone-coated PP product suitable for infants and children as described above is characterized in that: in step B, the bonding surface of the silicone is subjected to plasma treatment by a plasma vacuum machine, the treatment time is 25 minutes, and the temperature is 30°C.

[0014] The method for producing a silicone-coated PP product suitable for infants and children as described above is characterized in that: in step C, the oven baking time is 30 minutes and the baking temperature is 100°C.

[0015] The method for producing a silicone-coated PP product suitable for infants and children as described above is characterized in that: in step D, the baking temperature in the oven is 100° C. and the baking time is 20 minutes.

[0016] The method for making a silica gel-coated PP product suitable for infants and children as described above is characterized in that: in step E, a vacuum plasma machine is used, the vacuum degree is -97Kpa, and the time is 20 minutes.

[0017] As described above, a method for making a silicone-coated PP product suitable for infants and children is characterized in that the adhesive in step C is composed of the following raw materials in parts by weight: 5-8 parts of silicone resin, 10-20 parts of heptane, 5-10 parts of silane coupling agent, and 60-70 parts of solvent oil.

[0018] The beneficial effects of the present invention are as follows: adding POE and PA to PP can increase adhesion, increase the surface temperature of the plastic, increase toughness and improve strength. The semi-finished plastic product is placed in a plasma machine to attach ions to the plastic surface to increase adhesion. The silicone-coated plastic is baked before molding to increase the surface temperature and adhesion of the plastic. The silicone-coated product is finally surface treated by a plasma machine to remove surface impurities and pollutants, while improving its performance, corrosion resistance, adhesion, hydrophilicity and wear resistance. In this way, LSR silicone can be wrapped around the edge of the semi-finished plastic product to reduce material costs. Compared with pure silicone products, the cost can be reduced by about 70%. PP has a high hardness and can be used for connection and is easy to install. LSR silicone material has no usage restrictions and a high safety level.

Brief Description of the Drawings

[0019] Figure 1 A cross-sectional view of a product embodiment 1 made by the method of the present invention;

[0020] Figure 2 An exploded view of a product embodiment 1 made by the method of the present invention;

[0021] Figure 3 Schematic diagram of a mold for injecting LSR silicone rubber in Example 1 of the product made by the method of the present invention;

[0022] Figure 4 A cross-sectional view of a second embodiment of a product made by the method of the present invention;

[0023] Figure 5 This is an exploded view of product embodiment 2 made by the method of the present invention. [Specific implementation method]

[0024] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments:

[0025] A method for producing a silica gel-coated PP product suitable for infants and children, characterized by comprising the following steps:

[0026] A. Prepare PP (polypropylene), POE (POE plastic, polyvinyl ester copolymer), and PA (nylon) materials. First, heat PP to liquid state at 220°C, then add POE and increase the temperature to 240°C to mix PP and POE in liquid state, then add PA and continue to heat to 260°C to mix PP, POE, and PA in liquid state. The PP, POE, and PA liquid mixed raw materials are drawn through a plastic drawing machine and finally cut into granules. In order to ensure product performance, the weight proportions of PP, POE, and PA are 80%, 10%, and 10%, respectively. Add PP, POE, and PA to the plastic drawing machine in turn and heat to the corresponding temperature, then extrude and form through the screw of the extruder, and cut into granules to form composite plastic granules of PP, POE, and PA.

[0027] B. Put the above-mentioned granular material into a plastic injection molding machine, heat it until it melts, and inject it into the mold cavity of the injection molding machine to obtain a plastic semi-finished product. The shape of the mold cavity can correspond to the silicone parts on the baby bottle, pacifier, and breast pump. Finally, the semi-finished products of the baby bottle, pacifier, and breast pump parts are obtained. Put the plastic semi-finished product in a plasma machine and attach ions to the surface of the plastic semi-finished product. This can improve the surface viscosity and adhesion, making it easier to wrap and fit. In order to ensure performance, the processing time is 25 minutes and the temperature is 30°C.

[0028] C. Apply adhesive on the plastic surface. The full name of adhesive is silicone rubber glass adhesive. Due to the plasma surface treatment in step B, the adhesive is easier to bond to the plastic surface. By increasing the viscosity of the adhesive, the bonding strength between silicone and plastic can be increased. Bake in the oven for 20-50 minutes at a temperature of 100-110°C. The optimal time is 30 minutes at a temperature of 100°C. Baking ensures the adhesion and compounding, so that the glue and the plastic semi-finished product are firmly bonded.

[0029] D. After cooling, bake the semi-finished plastic product coated with adhesive in an oven at a temperature of 100°C for 20 minutes. Bake again to keep the special silicone water of the semi-finished plastic product sticky, and then put it into the mold cavity of the injection molding machine. Use a liquid silicone rubber injection molding machine, add LSR silicone (liquid silicone or liquid silicone) into the injection molding machine, control the temperature of LSR silicone between 140°C and 145°C, and vulcanize for 180 seconds to 200 seconds. Then, inject LSR silicone into the mold cavity so that LSR silicone is wrapped around the edge of the semi-finished plastic product, which is equivalent to encapsulation. This edge-to-edge wrapping means that the edge of the semi-finished plastic product is embedded in the LSR silicone. The LSR silicone can also be attached to the inner wall of the semi-finished plastic product. After encapsulating the silicone, the product is removed from the mold to obtain a product. In this way, the LSR silicone is wrapped around the outside of the semi-finished plastic product, and the PP composite material and the LSR silicone are firmly integrated through adhesive and high temperature.

[0030] E. After the mold is out, the product is placed in a plasma machine for surface treatment to obtain the final product. It is a vacuum plasma machine with a vacuum degree of -97Kpa and a time of 20 minutes. In this way, the LSR silicone is fused and wrapped around the PP, saving materials while ensuring the safety of the product. It takes advantage of the lightness, high toughness and good drop resistance of PP, combines the advantages of the two materials, and improves the competitiveness of the product.

[0031] The adhesive model in step C is 560P, and the adhesive has the following components and weight parts: 5-8 parts of silicone resin, 10-20 parts of heptane, 5-10 parts of silane coupling agent, 60-70 parts of solvent oil, the element encyclopedia CAS number (CASNo) of the silicone resin is 67763-03-5, the element encyclopedia CAS number of heptane is 142-82-5, and the element encyclopedia CAS number of solvent oil is 8030-30-6. One embodiment thereof is 7 parts of silicone resin, 15 parts of heptane, 10 parts of silane coupling agent, and 68 parts of solvent oil. Another embodiment is 7 parts of silicone resin, 15 parts of heptane, 9 parts of silane coupling agent, and 69 parts of solvent oil.

[0032] Products manufactured in this way, such as baby bottles, not only have the safety of LSR silicone, but also the lightness and drop resistance of plastic (PP), which is easy to connect. The hardness of plastic (PP) makes it easy to set threads for connection, which can give users more choices. The price is cheaper than silicone products and it is durable. When the product is a pacifier, it has the safety of LSR silicone and the strength of plastic, making the pacifier durable and not easily bitten. Threads can be set on the plastic to connect to the baby bottle, which is easy to produce and install.

[0033] Two product embodiments are given in this case. Embodiment 1 is a pacifier. Figure 1-3 As shown, the pacifier includes a plastic annular body 1 made of plastic (i.e., a mixed material of PP, POE, and PA) and a pacifier 2 made of LSR silicone. The plastic annular body 1 is formed by injection molding by an injection molding machine. The upper and lower ends of the plastic annular body 1 are open, and the upper end opening of the plastic annular body 1 gradually shrinks. When the LSR silicone is injected, the upper end of the plastic annular body 1 is inserted or embedded into the pacifier 2, so that the pacifier 2 is wrapped around the upper end of the plastic annular body 1. The middle part of the inner side wall of the plastic annular body 1 has a positioning step 11, and the lower end of the pacifier 2 extends into the plastic annular body 1. The lower end of the pacifier 2 has a positioning convex edge 21 that is abutted against the positioning step 11. The finished product made by the manufacturing method is combined into one with the plastic annular body 1 through the action of an adhesive, baking, and injection molding. The inner wall of the lower end of the plastic annular body 1 has a thread, which can be used to connect a feeding bottle.

[0034] Embodiment 2 is a feeding bottle, such as Figure 4-5As shown, it includes a hollow bottle body 3 with an upper opening, the bottle body 3 is made of LSR silicone material, and the upper end is a connecting ring 4, which is formed by injection molding by an injection molding machine. The connecting ring 4 is made of plastic material (i.e., a mixed material of PP, POE, and PA). After the LSR silicone is injected and overmolded, the lower edge of the connecting ring 4 will be embedded in the upper end of the bottle body 3. The outer wall of the connecting ring 4 has an external thread, and the side of the connecting ring 4 embedded in the bottle body 3 has a hole 41, so that the LSR silicone can be filled during the overmolding, so that the connecting ring 4 and the bottle body 3 are firmly connected, and the hole 41 can be shaped. The LSR silicone is transparent, so that the shape of the hole 41 can be seen, making the entire milk bottle more beautiful. Through the action of the adhesive, as well as baking and injection molding, the bottle body 3 and the connecting ring 4 are combined into one.

Claims

1. A method for producing a silica gel-coated PP product suitable for infants and children, characterized in that: The following steps are involved: A. Prepare PP, POE and PA materials. First, heat PP to liquid state, then add POE and increase the temperature to mix PP and POE in liquid state, then add PA and continue to heat to mix PP, POE and PA in liquid state. Then, draw the mixed raw materials of PP, POE and PA in liquid state through a plastic drawing machine and finally cut them into particles. B. Put the above granular material into a plastic injection molding machine, heat it until it melts, and inject it into the mold cavity of the injection molding machine to obtain a plastic semi-finished product. Put the plastic semi-finished product into a plasma machine to attach ions to the surface of the plastic semi-finished product; C. Apply adhesive on the plastic surface and bake in the oven for 20-50 minutes at a temperature of 100-110°C; D. After cooling, the plastic semi-finished product coated with the special adhesive is placed in an oven for baking, and then placed in the mold cavity of an injection molding machine. LSR silicone is added to the injection molding machine, and the temperature of the LSR silicone is controlled between 140°C and 145°C. After vulcanization for 180 seconds to 200 seconds, the LSR silicone is injected into the mold cavity so that the LSR silicone is wrapped around the edge of the plastic semi-finished product, and the product is removed from the mold after the silicone is wrapped. E. After the mold is finished, the product is placed in a plasma machine for surface treatment to obtain the final product.

2. A method for producing a silica gel-coated PP product suitable for infants and children according to claim 1, characterized in that: In step A, the weight proportions of PP, POE and PA are 80%, 10% and 10% respectively.

3. A method for producing a silica gel-coated PP product suitable for infants and children according to claim 1, characterized in that: The heating temperature of step APP is 220°C, the heating temperature of POE is 240°C, the heating temperature of PA is 260°C, and the heating temperature of the pellets in step B is 260°C.

4. A method for producing a silica gel-coated PP product suitable for infants and children according to claim 1, characterized in that: In step B, the bonding surface of the silicone is subjected to plasma treatment by a plasma vacuum machine, the treatment time is 25 minutes, and the temperature is 30°C.

5. A method for producing a silica gel-coated PP product suitable for infants and children according to claim 1, characterized in that: In step C, the oven baking time is 30 minutes and the baking temperature is 100°C.

6. A method for producing a silica gel-coated PP product suitable for infants and children according to claim 1, characterized in that: In step D, the baking temperature in the oven is 100° C. and the time is 20 minutes.

7. A method for producing a silica gel-coated PP product suitable for infants and children according to claim 1, characterized in that: In step E, a vacuum plasma machine is used, the vacuum degree is -97Kpa, and the time is 20 minutes.

8. A method for producing a silica gel-coated PP product suitable for infants and children according to claim 1, characterized in that: The adhesive in step C is composed of the following raw materials in parts by weight: 5-8 parts of organic silicone resin, 10-20 parts of heptane, 5-10 parts of silane coupling agent, and 60-70 parts of solvent oil.

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