Production process of mobile phone rear cover with 2.5 D touch texture

Abstract

The invention discloses a production process of a mobile phone rear cover with 2.5 D touch texture, which comprises a back surface treatment process and also comprises a front surface treatment process, and the front surface treatment process is realized through the following steps: step 1, groove milling treatment, step 2, curtain coating treatment, step 3, semi-curing treatment, step 4, texture forming, and step 5, curing forming. The texture part is put into a defoaming machine to be defoamed, LED lamp pre-curing treatment is conducted after defoaming, a texture sub-film is torn off at the pre-curing treatment position, then a mercury lamp is used for conducting full-curing hardening treatment on the texture part, and the 2.5 D mobile phone rear cover can be obtained after full-curing hardening treatment is conducted and high-pressure forming is conducted; the front face of the mobile phone rear cover can be directly subjected to texture processing through specific shower coating liquid, the smooth and matte effect of optical textures is achieved, the surface of the mobile phone rear cover is soft through the shower coating liquid on the front face of the mobile phone rear cover, concave-convex textures are matched, the three-dimensional effect is achieved, the good touch effect is achieved, and meanwhile it is guaranteed that the surface cannot crack during high-pressure forming.

Description

Technical Field

[0001] The present invention relates to the field of mobile phone accessory manufacturing, and particularly to a production process for a mobile phone back cover with a 2.5D tactile texture. Background Art

[0002] Conventionally sold back covers are generally made of plastic, glass, metal (mainly aluminum), and ceramic, each having different types of defects. For example: 1) Plastic back covers have low cost, are easy to process, and have no electromagnetic signal interference problems, but they have problems such as poor scratch resistance on the surface, poor texture, poor structural strength, and poor heat insulation; 2) Glass back covers have good scratch resistance on the surface, good texture, and no electromagnetic signal interference problems, but glass is fragile when dropped, and it cannot provide structural support by itself. Therefore, a metal middle frame needs to be designed in cooperation with the glass as the structural support member of the whole machine, which results in high cost and complex structure; 3) Metal aluminum back covers have advantages such as good structural strength, good heat dissipation, and good scratch resistance, but due to the electromagnetic signal interference problem of metals, plastic antenna strips need to be inlaid at both upper and lower ends of all metal back covers so that electromagnetic signals can be normally emitted, thus the appearance cannot maintain consistency. For this reason, there has emerged on the market a composite board in which a PMMA layer and a PC layer are laminated together as the raw material for the mobile phone back cover. When processing this composite board, spraying or transfer printing is used on the back of the mobile phone back cover to achieve the appearance decoration effect, so that the front of the mobile phone back cover is smooth, the front tactile feeling is hard, and the front of the mobile phone back cover cannot present an optical texture effect.

[0003] In view of this, the inventor of the present invention has conducted in-depth research on the above problems, and thus this case has arisen. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a production process for a mobile phone back cover with a 2.5D tactile texture to solve the problem that the surface of the existing mobile phone back cover is smooth, has a hard tactile feeling, and cannot present an optical texture effect.

[0005] To achieve the above object, the solution of the present invention is: a production process for a mobile phone back cover with a 2.5D tactile texture, having a back surface treatment process, wherein the back surface treatment process is: preparing a composite board with a PC surface on one side and a PMMA surface on the other side, and sequentially making a printed pattern layer, a transferred texture layer, a vacuum plating layer, and a base color ink printing layer on the PC surface to obtain a back surface treated part; it also includes a front surface treatment process, and the front surface treatment process is achieved through the following steps:

[0006] Step 1: Grooving treatment, performing grooving treatment on the side of the back surface treated part with the base color ink printing layer, dividing the side of the back surface treated part with the base color ink printing layer into several forming areas for respectively forming the mobile phone back cover, and covering the side of the back surface treated part with the base color ink printing layer with a protective film to obtain a grooved part;

[0007] Step 2: Flood coating treatment. Transfer the milled groove part to the flood coating area, clamp and fix the milled groove part vertically and suspended by a clip, then tear off the protective film on the PMMA surface of the milled groove part for cleaning. After cleaning, flood coat the PMMA surface of the milled groove part with flood coating glue to obtain a surface flood coated part with a flood coated surface. The flood coating glue is composed of polyacrylate, acrylic monomer, photoinitiator and additives, wherein polyacrylic acid accounts for 68 - 75% of the total weight, acrylate monomer accounts for 18 - 24% of the total weight, photoinitiator accounts for 3 - 6% of the total weight, and additives account for 2 - 4% of the total weight;

[0008] Step 3: Semi - solid treatment. Send the surface flood coated part obtained in Step 2 to the baking area for semi - drying treatment to obtain a semi - dried part;

[0009] Step 4: Texture forming. Send the semi - dried part to the texture forming area to perform texture embossing on the flood coated surface of the semi - dried part to obtain a textured part with a texture sub - film covered thereon;

[0010] Step 5: Curing and forming. Send the textured part into a defoaming machine for defoaming. After defoaming, perform LED lamp pre - curing treatment. During the pre - curing treatment, tear off the texture sub - film, and then use a mercury lamp to perform full - curing and hardening treatment on the textured part. After high - pressure forming in the full - curing and hardening treatment, a 2.5D mobile phone back cover can be obtained.

[0011] In Step 4, place the semi - dried part on a conveying platform. There are a protective film winding roller, a sub - film unwinding roller, a silicone roller, a steel roller and an electrostatic roller on the conveying platform. The protective film winding roller, the sub - film unwinding roller, the silicone roller and the electrostatic roller are all above the conveying platform. Taking the conveying direction of the conveying platform as the direction from left to right, the protective film winding roller is on the left side of the sub - film unwinding roller, the silicone roller is obliquely below and to the right of the sub - film unwinding roller, the steel roller is arranged directly above and below the silicone roller, and the steel roller is below the conveying platform. The above - mentioned electrostatic roller is on the right side of the silicone roller. There is a cutter on the right side of the above - mentioned electrostatic roller that can move up and down to cut the sub - film. The above - mentioned sub - film unwinding roller has a sub - film with a texture on one side and covered with a protective film. One end of the protective film is wound around the protective film winding roller, and one end of the sub - film is wound around one side of the silicone roller facing the steel roller.

[0012] The top surface of the above - mentioned conveying platform has two positioning baffles that are opposite front - to - back and extend in the left - right direction. The above - mentioned semi - dried part is clamped between the two positioning baffles. The positioning baffles are fixed to the conveying platform by screws, and the positioning baffles are provided with strip - shaped through - holes extending in the front - back direction for the screws to pass through.

[0013] The thickness of the above - mentioned composite board is 0.5mm - 1.0mm.

[0014] The thickness of the above - mentioned flood coating glue is 10 - 45um.

[0015] The above-mentioned auxiliary agent is composed of a perfluoroalkyl group and a silane. The perfluoroalkyl group accounts for 1-2% of the total weight of the dip-coating adhesive, and the silane accounts for 1-2% of the total weight of the dip-coating adhesive.

[0016] After adopting the above technical solution, in the production process of a 2.5D tactile texture mobile phone back cover of the present invention, a specific dip-coating liquid is used to directly process the texture on the front surface of the mobile phone back cover, achieving the light and matte effect of the optical texture. And the dip-coating liquid on the front surface of the mobile phone back cover makes the surface of the mobile phone back cover relatively soft. Combined with the concave and convex texture, it has a three-dimensional effect and a good tactile effect, while ensuring that the surface will not crack during high-pressure molding. Specific embodiments

[0017] In order to further explain the technical solution of the present invention, the present invention will be elaborated in detail below through specific embodiments.

[0018] The production process of a 2.5D tactile texture mobile phone back cover of the present invention has a back surface treatment process, and the back surface treatment process is as follows: Prepare a composite board with a PC surface on one side and a PMMA surface on the other side. The thickness of the composite board is 0.5 mm - 1.0 mm, and a printed pattern layer, a transferred texture layer, a vacuum plating layer, and a background color ink printing layer are sequentially made on the PC surface. The texture layer is 0.01 mm - 0.02 mm thick, and the background color ink printing layer is 0.04 mm - 0.06 mm thick to obtain a back surface treated part. The process of this back surface treated part is prior art and will not be repeated here.

[0019] The improvement of the present invention lies in that: the production process of the mobile phone back cover further includes a front surface treatment process, and the front surface treatment process is realized through the following steps:

[0020] Step 1: Grooving treatment. Grooving treatment is performed on the side of the back surface treated part with the background color ink printing layer, and several forming areas for respectively forming the mobile phone back cover are separated on the side of the back surface treated part with the background color ink printing layer. And a protective film is covered on the side of the back surface treated part with the background color ink printing layer to obtain a grooved part. For example, six forming areas for forming the mobile phone back cover arranged in two rows and three columns are directly milled out on a square composite board;

[0021] Step 2: Dip coating treatment. Transfer the grooved parts to the dip coating area, clamp and fix the grooved parts upright and suspend them, then tear off the protective film on the PMMA surface of the grooved parts for cleaning. After cleaning, dip coat the PMMA surface of the grooved parts with dip coating glue to obtain a surface dip-coated part with a dip-coated surface. The thickness of the dip coating glue is 10 - 45um. Only with this thickness of dip coating glue can the texture be clearly presented. The dip coating glue is composed of polyacrylate, acrylic monomer, photoinitiator, and additives. Among them, polyacrylic acid accounts for 68 - 75% of the total weight, acrylate monomer accounts for 18 - 24% of the total weight, photoinitiator accounts for 3 - 6% of the total weight, and additives account for 2 - 4% of the total weight. Preferably, polyacrylate accounts for 70% of the total weight, acrylate monomer accounts for 21% of the total weight, photoinitiator accounts for 6% of the total weight, and additives account for 3% of the total weight. This additive can only adopt the combination of perfluoroalkyl and silane. Perfluoroalkyl accounts for 1 - 2% of the total weight of the dip coating glue, and silane accounts for 1 - 2% of the total weight of the dip coating glue;

[0022] Step 3: Semi-curing treatment. Transfer the surface dip-coated part obtained in Step 2 to the baking area for semi-drying treatment to obtain a semi-dried part; during semi-curing, the baking temperature is 75 - 85°C, and the conveying speed of the surface dip-coated part is 1.3 - 1.8 m / min, that is, the line speed of the baking area is 1.3 - 1.8 m / min,

[0023] Step 4: Texture forming. Transfer the semi-dried part to the texture forming area and perform texture embossing forming treatment on the dip-coated surface of the semi-dried part to obtain a textured part with a texture sub-film covering it;

[0024] Step 5: Curing and forming. Send the textured part into a defoaming machine for defoaming. After defoaming, perform LED lamp pre-curing treatment. During the pre-curing treatment, tear off the texture sub-film, and then use a mercury lamp to perform full-curing and hardening treatment on the textured part. After high-pressure forming through the full-curing and hardening treatment, a 2.5D mobile phone back cover can be obtained.

[0025] The production process of a 2.5D tactile texture mobile phone back cover of the present invention uses a specific dip coating liquid to directly process the texture on the front of the mobile phone back cover, achieving the light and matte effect of the optical texture, and making the surface of the mobile phone back cover relatively soft with the dip coating liquid on the front of the mobile phone back cover. Combined with the concave and convex texture, it has a three-dimensional effect and a good tactile effect. At the same time, the grooving treatment in Step 1 can ensure that the surface will not crack during high-pressure forming.

[0026] In the present invention, in step four, the semi-dry processed piece is placed on the conveying platform. A protective film winding roller, a sub-mold unwinding roller, a silica gel roller, a steel roller and an electrostatic roller are provided at the conveying platform. The protective film winding roller, the sub-mold unwinding roller, the silica gel roller and the electrostatic roller are all located above the conveying platform. There are two positioning baffles on the top surface of the conveying platform that face each other front and back and extend in the left-right direction. The semi-dry processed piece is clamped between the two positioning baffles. The positioning baffles are locked to the conveying platform by screws, and strip-shaped through holes extending in the front-back direction for the screws to pass through are provided on the positioning baffles. Taking the conveying direction of the conveying platform as the direction from left to right, the protective film winding roller is on the left side of the sub-mold unwinding roller, the silica gel roller is obliquely below and to the right of the sub-mold unwinding roller, the steel roller is arranged directly above and below the silica gel roller, and the steel roller is below the conveying platform. The electrostatic roller is on the right side of the silica gel roller. A cutter capable of moving up and down to cut the sub-mold is provided on the right side of the electrostatic roller. The sub-mold on the sub-mold unwinding roller has a texture on one side and is covered with a protective film. One end of the above-mentioned protective film is wound around the protective film winding roller, and one end of the sub-mold is wound around the side of the silica gel roller facing the steel roller. The texture forming device with such a structure enables accurate alignment and forming during texture forming, ensuring the forming quality. In addition, the setting of the electrostatic roller can make the transfer of the sub-mold more accurate.

[0027] The above embodiments do not limit the method of the present invention. Any appropriate changes or modifications made by those of ordinary skill in the technical field to which the present invention pertains shall be regarded as not departing from the patent scope of the present invention.

Claims

1. A production process for the back cover of a mobile phone with 2.5D tactile texture, having a back surface treatment process, wherein the back surface treatment process is as follows: Prepare a composite board with a PC surface on one side and a PMMA surface on the other side, and sequentially apply a printed pattern layer, a transferred texture layer, a vacuum plating layer, and a base color ink printing layer on the PC surface to obtain a back surface treated part; characterized in that, It also includes a front surface treatment process, which is achieved through the following steps: Step 1: Grooving treatment. Grooving treatment is carried out on the side of the back surface treatment part where the base color ink printing layer is located, separating several forming areas for respectively forming the mobile phone back cover on the side of the back surface treatment piece where the base color ink printing layer is located, and covering the side of the back surface treatment part where the base color ink printing layer is located with a protective film to obtain a grooved part; Step 2: Pouring coating treatment. Transfer the grooved part to the pouring coating area, clamp and set the grooved part upright and suspended by a clip, then tear off the protective film on the PMMA surface of the grooved part for cleaning. After cleaning, pour coating glue is applied to the PMMA surface of the grooved part to obtain a surface pouring coated part with a pouring coated surface. The pouring coating glue is composed of polyacrylate, acrylic monomer, photoinitiator and additives, wherein polyacrylic acid accounts for 68 - 75% of the total weight, acrylate monomer accounts for 18 - 24% of the total weight, photoinitiator accounts for 3 - 6% of the total weight, and additives account for 2 - 4% of the total weight; Step 3: Semi-solid treatment. Send the surface pouring coated part obtained in Step 2 to the baking area for semi-drying treatment to obtain a semi-dried part; Step 4: Texture forming. Send the semi-dried part to the texture forming area to carry out texture embossing forming treatment on the pouring coated surface of the semi-dried part to obtain a textured part covered with a texture sub-film; Step 5: Curing and forming. Send the textured part into a defoaming machine for defoaming. After defoaming, carry out LED lamp pre-curing treatment. During the pre-curing treatment, tear off the texture sub-film, and then use a mercury lamp to carry out full-curing and hardening treatment on the textured part. After high-pressure forming in the full-curing and hardening treatment, a 2.5D mobile phone back cover can be obtained.

2. The production process of a 2.5D tactile texture mobile phone back cover according to claim 1, characterized in that: In Step 4, place the semi-dried part on a conveying platform. There are a protective film winding roller, a sub-film unwinding roller, a silicone roller, a steel roller and an electrostatic roller at the conveying platform. The protective film winding roller, the sub-film unwinding roller, the silicone roller and the electrostatic roller are all above the conveying platform. Taking the conveying direction of the conveying platform as the direction from left to right, the protective film winding roller is on the left side of the sub-film unwinding roller, the silicone roller is obliquely below and to the right of the sub-film unwinding roller, the steel roller is arranged directly above and below the silicone roller, and the steel roller is below the conveying platform. The above-mentioned electrostatic roller is on the right side of the silicone roller. There is a cutter on the right side of the above-mentioned electrostatic roller that can move up and down to cut the sub-film. The above-mentioned sub-film unwinding roller has a sub-film with texture on one side and covered with a protective film. One end of the above-mentioned protective film is wound around the protective film winding roller, and one end of the sub-film is wound around the side of the silicone roller facing the steel roller.

3. The production process of a 2.5D tactile texture mobile phone back cover according to claim 2, characterized in that: The top surface of the above-mentioned conveying platform has two positioning baffles that are opposite front and back and extend in the left-right direction. The above-mentioned semi-dried part is clamped between the two positioning baffles. The positioning baffles are locked to the conveying platform by screws, and the positioning baffles are provided with strip-shaped through holes extending in the front-back direction for the screws to pass through.

4. The production process of a 2.5D tactile texture mobile phone back cover according to claim 1, characterized in that: The thickness of the above-mentioned composite board is 0.5mm - 1.0mm.

5. The production process of a 2.5D tactile texture mobile phone back cover according to claim 1, characterized in that: The thickness of the above-mentioned pouring coating glue is 10 - 45um.

6. The production process of the 2.5D tactile texture mobile phone back cover according to claim 1, characterized in that: The above-mentioned additives are composed of perfluoroalkyl and silane. Perfluoroalkyl accounts for 1 - 2% of the total weight of the pouring coating glue, and silane accounts for 1 - 2% of the total weight of the pouring coating glue.