Release silicone oil and preparation method of label backing paper

Abstract

The invention relates to the technical field of thermo-sensitive paper, in particular to a preparation method of release silicone oil and label backing paper.The preparation method comprises the following steps that 1, methylcyclosiloxane and tetramethyltetravinylcyclotetrasiloxane are mixed, stirred and heated; 2, carrying out a polymerization reaction under the action of a vinyl end-capping reagent and a basic catalyst, and after the polymerization reaction is finished, carrying out cooling, dilute acid neutralization, water washing and separation to obtain a polymerization solution; 3, rectifying the polymer liquid to remove low-boiling-point substances to obtain vinyl silicone oil; 4, a cross-linking agent is added into the vinyl silicone oil to be evenly stirred, then a platinum catalyst is added to be mixed, and the release silicone oil coating liquid is obtained.After the surface of the single-gloss paper is coated with the primer coating, a compact protection film is generated through drying and cross-linking, pores in the surface of the paper are sealed, and the silicone oil is prevented from permeating into the paper during silicon coating; the silicone oil furthest stays on the surface of the paper and is cured to form a compact release layer, thereby reducing the gram weight of coated silicon and saving the cost.

Description

Technical Field

[0001] The invention relates to the technical field of thermal paper, and in particular to a preparation method of release silicone oil and label base paper. Background Art

[0002] Labels are widely used in supermarkets, logistics and other fields. They are daily consumables and are closely related to our lives and work. The base paper is the carrier of the label, but after each printing and labeling, the base paper becomes waste. The labels currently sold on the market use glassine base paper or film release film, which have complex processing procedures and high costs. Summary of the invention

[0003] The purpose of the present invention is to solve the above-mentioned shortcomings in the prior art and to propose a method for preparing release silicone oil and label backing paper.

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

[0005] A method for preparing release silicone oil is designed, which is characterized by comprising the following steps:

[0006] 1. Mixing, stirring and heating methylcyclosiloxane and tetramethyltetravinylcyclotetrasiloxane;

[0007] Second, a polymerization reaction occurs under the action of a vinyl end-capping agent and an alkaline catalyst, and after the polymerization reaction is completed, the polymerization liquid is obtained by cooling, neutralizing with dilute acid, washing with water, and separating;

[0008] 3. The polymer solution is distilled to remove low-boiling substances to obtain vinyl silicone oil;

[0009] Fourth, the vinyl silicone oil is added with a cross-linking agent and stirred evenly, and then a platinum catalyst is added and mixed, and stirred for 15-30 minutes at an ambient temperature of 20°C-25°C to prepare a release silicone oil coating liquid, wherein the vinyl silicone oil, the cross-linking agent, and the platinum catalyst are calculated by weight in proportions of 100 parts, 1.8-2.2 parts, and 1.2-1.5 parts, respectively.

[0010] A method for preparing a label backing paper, comprising the method for preparing the release silicone oil according to claim 1, characterized in that it comprises the following steps:

[0011] First, the primer is applied to the surface of the single-gloss paper by a coating device, and dried and cross-linked to produce a dense protective film;

[0012] Second, the release silicone oil coating liquid is coated on the surface of the protective film by using an oil coating device, and solidified to form a dense release layer.

[0013] Furthermore, the oiling device includes a frame, a cylinder arranged above the frame, a brushing assembly connected to the cylinder, an oil quantity control assembly arranged in the cylinder, and a driving assembly for driving the cylinder to move above the label base paper. The moving direction of the brushing assembly and the conveying direction of the label base paper are perpendicular to each other. The driving assembly controls the movement of the cylinder to achieve the control of the amount of release silicone oil flowing from the cylinder to the brushing assembly through the oil quantity control assembly.

[0014] Furthermore, the painting brush assembly includes first bristles located in the barrel and second bristles connected to the first bristles and located outside the barrel.

[0015] Furthermore, the oil quantity control assembly includes a positioning cover surrounding the outside of the first bristles and forming a cavity with the bottom of the cylinder, a through hole obliquely opened on the positioning cover, a rotating rod rotatably connected to the center of the top of the cylinder, and a stirring rod arranged on the rotating rod.

[0016] Furthermore, the extending direction of the through hole and the axial axis of the positioning cover have an angle a, wherein 30° <a<60°。

[0017] Furthermore, the oil quantity control assembly also includes an auxiliary absorption part, wherein the auxiliary absorption part includes a plurality of circular rings gradually decreasing from the edge of the cylinder to the center, a first protrusion arranged on both sides of the circular rings, a second protrusion arranged on the outer wall of the positioning cover, and a longitudinal connecting rod connecting the circular rings and the stirring rod.

[0018] Furthermore, the driving assembly includes a transverse plate, a top plate connecting the transverse plate and the cylinder, a power unit for pushing the transverse plate to move, and a linkage unit for driving the rotating rod to rotate.

[0019] Furthermore, the power unit includes a screw rod threadedly connected to the transverse plate, and a motor disposed on the frame for driving the screw rod to rotate.

[0020] Furthermore, the linkage part includes a rack plate arranged on the frame, an inner recessed opening opened on the transverse plate for the rack plate to pass through, and a gear arranged on the top plate and meshing with the rack plate.

[0021] The invention provides a method for preparing a release silicone oil and a label backing paper, which has the following beneficial effects:

[0022] After the primer is applied to the surface of the single-gloss paper, it is dried and cross-linked to form a dense protective film, which closes the pores on the surface of the paper. When the silicone is applied, the silicone oil is prevented from penetrating into the inside of the paper. The silicone oil stays on the surface of the paper to the maximum extent and solidifies to form a dense release layer, thereby reducing the weight of the silicone coating and saving costs.

[0023] The present invention applies the primer coating layer coating liquid to the surface of the single-gloss paper and dries and solidifies it, while producing a dense surface seal, the single-gloss paper fibers and the PVA in the coating are cross-linked to increase the tensile and tearing strength of the paper, and then the silicon coating is cured to form a film and cross-linked to further strengthen it. Finally, the release paper prepared after the coating coating is cured and the silicon coating is cured can be used to replace the glassine base paper;

[0024] The present invention controls the movement of the cylinder through a driving component, so as to control the amount of release silicone oil flowing from the cylinder to the brushing component through an oil quantity control component, thereby ensuring that the silicone oil can be evenly coated on the surface of the protective film and improving the silicone oil coating effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the structure of the present invention;

[0026] Figure 2 A top view of the present invention;

[0027] Figure 3 It is a schematic diagram of the internal structure of the cylinder;

[0028] Figure 4 is a schematic diagram of the auxiliary absorption part;

[0029] Figure 5 is a cross-sectional view of the auxiliary absorption part; DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0031] A method for preparing release silicone oil comprises the following steps:

[0032] 5. mixing, stirring and heating methylcyclosiloxane and tetramethyltetravinylcyclotetrasiloxane;

[0033] Sixth, a polymerization reaction occurs under the action of a vinyl end-capping agent and an alkaline catalyst, and after the polymerization reaction is completed, the polymerization liquid is obtained by cooling, neutralizing with a dilute acid, washing with water, and separating;

[0034] Seventh, the polymer liquid is distilled to remove low-boiling substances to obtain vinyl silicone oil;

[0035] 8. Add the cross-linking agent to the vinyl silicone oil and stir evenly, then add the platinum catalyst and mix, stir for 15-30 minutes at an ambient temperature of 20°C-25°C to prepare a release silicone oil coating liquid, wherein the vinyl silicone oil, the cross-linking agent, and the platinum catalyst are calculated by weight: 100 parts, 1.8-2.2 parts, and 1.2-1.5 parts, respectively.

[0036] A method for preparing a label backing paper, comprising the method for preparing the release silicone oil according to claim 1, comprising the following steps:

[0037] Third, a primer coating is applied to the surface of the single-gloss paper by a coating device, and dried and cross-linked to produce a dense protective film. The primer coating formula in this example includes a PVA1788 solution with a medium degree of polymerization, a cross-linking agent, and a defoaming agent, wherein the cross-linking agent is trimethylolpropane-tris[3-(2-methylaziridinyl)]propionate, and the defoaming agent is SURFYNOL 104E;

[0038] Fourth, using an oil coating device to apply a release silicone oil coating liquid on the surface of the protective film, and solidifying it to form a dense release layer;

[0039] After the primer coating is applied to the surface of the single-gloss paper, it dries and cross-links to produce a dense protective film, which closes the pores on the surface of the paper and prevents the silicone oil from penetrating into the inside of the paper when silicone is applied. The silicone oil stays on the surface of the paper to the maximum extent and solidifies to form a dense release layer, thereby reducing the weight of the silicone coating and saving costs; the primer coating layer is applied to the surface of the single-gloss paper and dries and solidifies to produce a dense surface seal. At the same time, the single-gloss paper fibers and the PVA in the coating cross-link with each other, increasing the tensile and tearing strength of the paper, and then the silicone coating is cured to form a film and cross-linked, which is further strengthened. Finally, the release paper prepared after the coating coating is cured and the silicone coating is cured can be used to replace the glassine base paper.

[0040] In an optional embodiment of the present invention, Figure 1-5 As shown, the oiling device includes a frame 1, a cylinder 2 arranged above the frame 1, a brushing assembly 3 connected to the cylinder 2, an oil quantity control assembly 4 arranged in the cylinder 2, and a driving assembly 5 for driving the cylinder 2 to move above the label backing paper. The moving direction of the brushing assembly 3 and the conveying direction of the label backing paper are perpendicular to each other. The driving assembly 5 controls the movement of the cylinder 2 to achieve the control of the amount of release silicone oil flowing from the cylinder 2 to the brushing assembly 3 through the oil quantity control assembly 4. Preferably, an oil inlet 201 is provided on the top of the cylinder 2 of this embodiment, and the release silicone oil enters the cylinder 2 through the oil inlet 201. The present invention controls the movement of the cylinder 2 through the driving assembly 5 to achieve the control of the amount of release silicone oil flowing from the cylinder 2 to the brushing assembly 3 through the oil quantity control assembly 4, thereby ensuring that the silicone oil can be evenly coated on the surface of the protective film and improving the silicone oil coating effect.

[0041] In an alternative embodiment of the present invention, the coating assembly 3 includes a first brush hair 301 located inside the cylinder body 2 and a second brush hair 302 connected to the first brush hair 301 and located outside the cylinder body 2. Preferably, in this embodiment, the diameter of the first brush hair 301 is greater than that of the second brush hair 302, and the first brush hair 301 and the second brush hair 302 are distributed in a circular array from the edge of the bottom of the cylinder body 2 towards the center; the first brush hair 301 is used to absorb the release silicone oil inside the cylinder body 2 and flow towards the second brush hair 302, and by moving back and forth above the label backing paper, the silicone oil is coated on the label backing paper.

[0042] In an alternative embodiment of the present invention, the oil quantity control assembly 4 includes a positioning cover 401 surrounding the outside of the first brush hair 301 and forming a cavity 402 with the bottom of the cylinder body 2, a through hole 403 obliquely opened on the positioning cover 401, a rotating rod 404 rotatably connected to the center of the top of the cylinder body 2, and a stirring rod 405 provided on the rotating rod 404. Preferably, in this embodiment, the first brush hair 301 is fixedly connected to the top of the positioning cover 401, the rotating rod 404 is rotatably connected to the top of the cylinder body 2, three groups of stirring rods 405 are provided, and the length of the stirring rod 405 gradually increases from the top of the cylinder body 2 towards the bottom; after the rotating rod 404 drives the stirring rod 405 to rotate, the release silicone oil entering the cylinder body 2 is stirred to make the concentration distribution of the silicone oil more uniform. At the same time, the silicone oil stirred by the stirring rod 405 is in a rotating state and quickly enters the cavity 402 through the through hole 403, and the first brush hair 301 absorbs the release silicone oil inside the cylinder body 2 and flows towards the second brush hair 302.

[0043] In an alternative embodiment of the present invention, the extending direction of the through hole 403 and the axial center line of the positioning cover 401 have an included angle a, where 30° < a < 60°. Such a setting makes the rotating direction of the silicone oil stirred by the stirring rod 405 more consistent with the direction of the through hole 403, facilitating the rapid entry of the silicone oil into the positioning cover 401, reducing delay, and improving the silicone oil coating effect.

[0044] In an optional embodiment of the present invention, the oil quantity control component 4 also includes an auxiliary absorption part 406, wherein the auxiliary absorption part 406 includes a plurality of circular rings 4061 which gradually decrease from the edge of the cylinder 2 to the center, a first protrusion 4062 provided on both sides of the circular ring 4061, a second protrusion 4063 provided on the outer wall of the positioning cover 401, and a longitudinal connecting rod 4064 connecting the circular ring 4061 and the stirring rod 405. Preferably, the circular ring 4061 in this embodiment is located in the gap between adjacent positioning covers 401, the first protrusion 4062 and the second protrusion 4063 are implemented with rubber, and the first protrusion 4062 and the second protrusion 4063 are slidably matched; during the rotation of the stirring rod 405, the circular ring 4061 is driven to rotate by the longitudinal connecting rod 4064, so that the first protrusion 4062 continuously hits the second protrusion 4063, and then transmits the vibration to the first bristles 301, so that the first bristles 301 vibrate slightly in the cavity 402 and quickly absorb the release silicone oil.

[0045] In an optional embodiment of the present invention, the driving assembly 5 includes a transverse plate 501, a top plate 502 connecting the transverse plate 501 and the cylinder 2, a power unit 503 for pushing the transverse plate 501 to move, and a linkage unit 504 for driving the rotating rod 404 to rotate.

[0046] In an optional embodiment of the present invention, the power unit 503 includes a screw rod 5031 screwed to the transverse plate 501, and a motor 5032 arranged on the frame 1 for driving the screw rod 5031 to rotate. Preferably, the power unit 503 in this embodiment can be provided with two groups, which are respectively arranged at both ends of the transverse plate 501; the screw rod 5031 is driven to rotate by the motor 5032, thereby driving the transverse plate 501 to move, and then driving the brush assembly 3 to move above the label base paper.

[0047] In an optional embodiment of the present invention, the linkage part 504 includes a rack plate 5041 arranged on the frame 1, an inner recess 5042 opened on the transverse plate 501 for the rack plate 5041 to pass through, and a gear 5043 arranged on the top plate 502 and meshing with the rack plate 5041. Preferably, the gear 5043 and the rotating rod 404 in this embodiment are fixedly connected; the transverse plate 501 drives the gear 5043 to move along the rack plate 5041, so that the gear 5043 drives the rotating rod 404 to rotate, and then drives the stirring rod 405 to rotate in the cylinder 2.

[0048] The above are only preferred specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and inventive concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a release silicone oil, characterized in that: The following steps are included:

1. Mixing, stirring and heating methylcyclosiloxane and tetramethyltetravinylcyclotetrasiloxane; Second, a polymerization reaction occurs under the action of a vinyl end-capping agent and an alkaline catalyst, and after the polymerization reaction is completed, the polymerization liquid is obtained by cooling, neutralizing with dilute acid, washing with water, and separating; 3. The polymer solution is distilled to remove low-boiling substances to obtain vinyl silicone oil; Fourth, the vinyl silicone oil is added with a cross-linking agent and stirred evenly, and then a platinum catalyst is added and mixed, and stirred for 15-30 minutes at an ambient temperature of 20°C-25°C to prepare a release silicone oil coating liquid, wherein the vinyl silicone oil, the cross-linking agent, and the platinum catalyst are calculated by weight in proportions of 100 parts, 1.8-2.2 parts, and 1.2-1.5 parts, respectively.

2. A method for preparing a label backing paper, comprising the method for preparing the release silicone oil according to claim 1, characterized in that: The following steps are included: First, the primer is applied to the surface of the single-gloss paper by a coating device, and dried and cross-linked to produce a dense protective film; Second, the release silicone oil coating liquid is coated on the surface of the protective film by using an oil coating device, and solidified to form a dense release layer.

3. The method for producing a label backing paper according to claim 2, characterized in that: The oiling device comprises a frame (1), a cylinder (2) arranged above the frame (1), a brushing assembly (3) connected to the cylinder (2), an oil quantity control assembly (4) arranged in the cylinder (2), and a driving assembly (5) for driving the cylinder (2) to move above the label backing paper, wherein the moving direction of the brushing assembly (3) and the conveying direction of the label backing paper are perpendicular to each other, and the driving assembly (5) controls the moving speed of the cylinder (2) so as to control the amount of release silicone oil flowing from the cylinder (2) to the brushing assembly (3) through the oil quantity control assembly (4).

4. The method for producing a label backing paper according to claim 3, characterized in that: The painting brush assembly (3) comprises first bristles (301) located inside the barrel (2) and second bristles (302) connected to the first bristles (301) and located outside the barrel (2).

5. The method for producing a label backing paper according to claim 4, characterized in that: The oil quantity control assembly (4) comprises a positioning cover (401) which surrounds the outside of the first bristles (301) and forms a cavity (402) with the bottom of the barrel (2), a through hole (403) obliquely opened on the positioning cover (401), a rotating rod (404) rotatably connected to the center of the top of the barrel (2), and a stirring rod (405) arranged on the rotating rod (404).

6. The method for producing a label backing paper according to claim 5, characterized in that: The extending direction of the through hole (403) and the axial axis of the positioning cover (401) have an angle a, wherein 30° <a<60°。 7. The method for producing a label backing paper according to claim 5, characterized in that: The oil quantity control assembly (4) further comprises an auxiliary absorption part (406), wherein the auxiliary absorption part (406) comprises a plurality of circular rings (4061) which gradually decrease in size from the edge of the cylinder (2) to the center, a first protrusion (4062) provided on both sides of the circular rings (4061), a second protrusion (4063) provided on the outer wall of the positioning cover (401), and a longitudinal connecting rod (4064) connecting the circular rings (4061) and the stirring rod (405).

8. The method for producing a label backing paper according to claim 5, characterized in that: The driving assembly (5) comprises a transverse plate (501), a top plate (502) connecting the transverse plate (501) and the cylinder (2), a power unit (503) for pushing the transverse plate (501) to move, and a linkage unit (504) for driving the rotating rod (404) to rotate.

9. The method for producing a label backing paper according to claim 8, characterized in that: The power unit (503) comprises a screw rod (5031) threadedly connected to the transverse plate (501), and a motor (5032) disposed on the frame (1) and used for driving the screw rod (5031) to rotate.

10. The method for producing a label backing paper according to claim 8, characterized in that: The linkage part (504) comprises a rack plate (5041) arranged on the frame (1), an inner recess (5042) provided on the transverse plate (501) for the rack plate (5041) to pass through, and a gear (5043) arranged on the top plate (502) and meshing with the rack plate (5041).

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