Fixing film with thermal shrinkage effect and preparation method thereof

Abstract

The invention relates to a photographic fixing film with a heat shrinkage effect and a preparation method thereof. The photographic fixing film is of a multi-layer structure and sequentially comprises a base material, a bottom coating layer, a silica gel layer, a surface coating layer and a heat shrinkage layer from inside to outside. The heat shrinkage layer is prepared from the following components in parts by mass: 30 to 50 parts of PFA resin, 40 to 50 parts of polyethylene, 10 to 30 parts of polyurethane, 5 to 10 parts of polytetrafluoroethylene, 5 to 8 parts of modified silicon dioxide particles and 1 to 5 parts of auxiliaries; wherein the modified silicon dioxide particles are a product obtained by copolymerizing hydroxylated silicon dioxide, silicon dioxide partially grafted with perfluorinated acid and silicon dioxide partially grafted with unsaturated carboxylic acid with acrylate. The release layer pipe sleeve with the thermal shrinkage effect prepared by the invention not only has good mechanical properties, but also can uniformly shrink after being heated, avoids the formation of defects such as bubbles and wrinkles, has a smoother surface, improves the production efficiency, and overcomes the defects in the prior art.

Description

Technical Field

[0001] The invention belongs to the field of polymer materials, and in particular relates to a fixing film with a heat shrinking effect and a preparation method thereof. Background Art

[0002] The fuser film, also known as the fuser roller, is a key component for fixing the copied or printed toner image in office equipment such as copiers or printers.

[0003] During the copying or printing process, after the image formed by the toner is transferred to the surface of the paper, the paper is then fed into the fixing assembly. The upper roller of the fixing assembly uses the high temperature released by the built-in heating lamp to transfer heat energy to the toner image on the paper; at the same time, the lower roller applies a certain pressure to the upper roller, causing the toner image to melt rapidly under the combined action of high temperature and pressure, and fit tightly into the paper fibers. Then, as the upper and lower rollers rotate in coordination, the paper is transported to the paper output tray of the copier, ending the fixing process.

[0004] The fixing film is usually composed of a base, a silicone layer, a coating layer and a tube sleeve, wherein the tube sleeve is usually a fluorine-containing resin material, i.e., a fluorine sleeve. Compared with polyvinyl chloride and polyethylene, this type of material has a higher operating temperature, mechanical strength and better non-stickiness, and has good density, and can prevent the penetration of water vapor and the erosion of corrosive gases. However, the prior art requires the addition of an adhesive between the coating layer and the tube sleeve layer to more tightly connect the two. However, the addition of an adhesive not only makes the preparation process more complicated, the subsequent drying process more cumbersome, but also easily introduces bubbles, resulting in loosening, wrinkles, and insufficient flatness of the fixing film surface, which seriously affects the effect of the subsequent printing process. There are major defects and it is difficult to meet the needs of current consumers.

[0005] In summary, it is urgent to develop a new technical solution to solve the problems existing in the prior art. Summary of the invention

[0006] Based on this, the present invention provides a fixing film with a heat shrinkage effect and a preparation method thereof. The fixing film adopts PFA resin, polyethylene, polyurethane and other materials as a base resin, and uses perfluoro acid, unsaturated carboxylic acid and acrylic acid to modify silica to obtain a release layer tube sleeve with a heat shrinkage effect. The release layer tube sleeve not only has good mechanical properties, but also can shrink evenly after heating, avoiding the formation of defects such as bubbles and wrinkles, having a smoother surface, and improving production efficiency, thereby overcoming the shortcomings of the prior art.

[0007] An object of the present invention is to provide a fixing film with a heat shrinking effect, wherein the fixing film has a multi-layer structure, and comprises, from inside to outside, a substrate, a primer layer, a silicone layer, a topcoat layer and a heat shrinking layer;

[0008] The heat shrinkable layer comprises the following components in parts by weight:

[0009]

[0010]

[0011] The modified silicon dioxide particles are the product of hydroxylated silicon dioxide, silicon dioxide partially grafted with perfluorinated acid and partially grafted with unsaturated carboxylic acid, and then copolymerized with acrylate.

[0012] Furthermore, the perfluoro acid is selected from one or more of perfluorotridecanoic acid, perfluorohexanoic acid, perfluoroheptanoic acid or a mixture thereof.

[0013] Furthermore, the unsaturated carboxylic acid is selected from one or more of acrylic acid and methacrylic acid.

[0014] Furthermore, the acrylic acid ester is selected from one or more of butyl acrylate, octyl acrylate and dodecyl acrylate.

[0015] Furthermore, the auxiliary agent is selected from one or more of a catalyst, an initiator, a cross-linking agent, a coupling agent, a lubricant, an antioxidant, a film-forming aid, and a dispersant.

[0016] Furthermore, the substrate is preferably a polyimide substrate, the primer layer and the topcoat layer are preferably fluorine-containing coatings, and the silicone layer is preferably a thermally conductive silicone rubber elastomer.

[0017] Another object of the present invention is to provide a method for preparing the above-mentioned fixing film with heat shrinking effect, wherein the method for preparing the fixing film with heat shrinking effect comprises the following steps:

[0018] S1, blending a perfluoro acid and an unsaturated acid, adding a solvent, and stirring to form a blend;

[0019] S2, immersing hydroxylated silicon dioxide in the blend, ultrasonically heating, and reacting to form an intermediate product;

[0020] S3, subjecting the intermediate product to free radical polymerization with acrylate to form modified silica particles;

[0021] S4, mixing the modified silicon dioxide particles and other ingredients, and extruding to obtain a heat shrinkable layer tube sleeve;

[0022] S5, inserting the tube core containing the substrate, the primer layer, the silicone layer and the top layer into the heat shrinkable layer tube sleeve to obtain a product.

[0023] Furthermore, the molar ratio of the perfluoro acid to the unsaturated carboxylic acid is 1:(1-3).

[0024] Furthermore, the temperature of the ultrasonic heating is 60-90°C.

[0025] Furthermore, the mass ratio of the intermediate product to the acrylic ester is (0.1-5):1.

[0026] Furthermore, the temperature of the free radical polymerization is 50-100°C.

[0027] The beneficial effects of the present invention are:

[0028] The present invention adopts PFA resin, polyethylene, polyurethane and polytetrafluoroethylene as matrix materials, and compound with modified silica to obtain a heat shrinkable layer. Among them, the modified silica first reacts hydroxylated silica with perfluoroheptanoic acid and acrylic acid, introduces perfluoroalkyl chains and unsaturated double bonds into the silica surface, and then performs free radical polymerization with alkyl acrylate to further introduce polymer structure, so that the obtained modified silica improves the compatibility with materials such as fluorine-containing resin, polyethylene, polyurethane, etc., can be more evenly distributed in the system, more stably combined with resin, and form a uniform network structure, thereby promoting mechanical properties, and can further improve the stability and uniformity during shrinkage, which is conducive to increasing the compactness, thermal conductivity and brightness of the pipe sleeve. In short, the present invention does not need to add adhesive to the outside of the surface coating, simplifies the preparation process, improves production efficiency, effectively avoids the appearance of bubbles and wrinkles, improves the various properties of the fixing film, and solves the problems existing in the prior art. DETAILED DESCRIPTION

[0029] In order to more clearly illustrate the technical solution of the present invention, the following examples are listed. Unless otherwise stated, the raw materials, reactions and post-treatment methods shown in the examples are common raw materials on the market and technical methods well known to those skilled in the art.

[0030] The PFA resin in the embodiment of the present invention is DuPont 451HP.

[0031] The polyethylene in the embodiment of the present invention is HD5301AA.

[0032] The polyurethane in the embodiment of the present invention is a thermoplastic polyurethane containing polymerizable unsaturated groups. n =5000-12000.

[0033] The preparation method of hydroxylated silicon dioxide in the embodiment of the present invention comprises the following steps: immersing silicon dioxide in a mixture of concentrated sulfuric acid and hydrogen peroxide (mass concentration 30%) in a volume ratio of 70:30, heating at 70° C. for reaction for 1 hour, washing and drying to obtain hydroxylated silicon dioxide.

[0034] The "parts" in the embodiments of the present invention refer to parts by mass.

[0035] Example 1

[0036] A fixing film with a heat shrinking effect, the fixing film having a multi-layer structure, comprising from the inside to the outside: a substrate, a primer layer, a silicone layer, a topcoat layer and a heat shrinking layer;

[0037] The heat shrinkable layer comprises the following components in parts by weight:

[0038]

[0039] The method for preparing the fixing film with heat shrinking effect comprises the following steps:

[0040] S1. Using dichloromethane as a solvent, blending perfluoroheptanoic acid and acrylic acid in a molar ratio of 1:1, and stirring to form a blend;

[0041] S2, immersing hydroxylated silica in the blend (the mass ratio of hydroxylated silica to perfluoroheptanoic acid is 2:1), ultrasonically reacting at 70° C. for 10 h, filtering, washing, and drying to obtain an intermediate product;

[0042] S3, using water as solvent, mixing the intermediate product, butyl acrylate, sodium dodecyl sulfate and potassium persulfate in a mass ratio of 8:2:0.5:0.1, reacting at 85° C. for 5 h under a nitrogen atmosphere, filtering, washing and drying to obtain modified silica particles;

[0043] S4, according to the above mass fractions, the modified silicon dioxide particles and other ingredients are mixed and stirred uniformly, added into an extruder, extruded at 200-300° C., and subjected to inflation treatment (inflation ratio of 2) to obtain a heat shrinkable layer tube sleeve;

[0044] S5. Insert the tube core containing the substrate, the primer layer, the silicone layer and the top layer into the heat shrinkable layer tube sleeve, and heat at 300-310° C. for 4 minutes to obtain a product.

[0045] Example 2

[0046] A fixing film with a heat shrinking effect, the fixing film having a multi-layer structure, comprising from the inside to the outside: a substrate, a primer layer, a silicone layer, a topcoat layer and a heat shrinking layer;

[0047] The heat shrinkable layer comprises the following components in parts by weight:

[0048]

[0049] The method for preparing the fixing film with heat shrinking effect comprises the following steps:

[0050] S1. Using dichloromethane as a solvent, blending perfluoroheptanoic acid and acrylic acid in a molar ratio of 1:1, and stirring to form a blend;

[0051] S2, immersing hydroxylated silica in the blend (the mass ratio of hydroxylated silica to perfluoroheptanoic acid is 2:1), ultrasonically reacting at 70° C. for 10 h, filtering, washing, and drying to obtain an intermediate product;

[0052] S3, using water as solvent, mixing the intermediate product, butyl acrylate, sodium dodecyl sulfate and potassium persulfate in a mass ratio of 8:2:0.5:0.1, reacting at 85° C. for 5 h under a nitrogen atmosphere, filtering, washing and drying to obtain modified silica particles;

[0053] S4, according to the above mass fractions, the modified silicon dioxide particles and other ingredients are mixed and stirred uniformly, added into an extruder, extruded at 200-300° C., and subjected to inflation treatment (inflation ratio of 2) to obtain a heat shrinkable layer tube sleeve;

[0054] S5. Insert the tube core containing the substrate, the primer layer, the silicone layer and the top layer into the heat shrinkable layer tube sleeve, and heat at 300-310° C. for 4 minutes to obtain a product.

[0055] Example 3

[0056] A fixing film with a heat shrinking effect, the fixing film having a multi-layer structure, comprising from the inside to the outside: a substrate, a primer layer, a silicone layer, a topcoat layer and a heat shrinking layer;

[0057] The heat shrinkable layer comprises the following components in parts by weight:

[0058]

[0059] The method for preparing the fixing film with heat shrinking effect comprises the following steps:

[0060] S1. Using dichloromethane as a solvent, blending perfluoroheptanoic acid and acrylic acid in a molar ratio of 1:1, and stirring to form a blend;

[0061] S2, immersing hydroxylated silica in the blend (the mass ratio of hydroxylated silica to perfluoroheptanoic acid is 2:1), ultrasonically reacting at 70° C. for 10 h, filtering, washing, and drying to obtain an intermediate product;

[0062] S3, using water as solvent, mixing the intermediate product, butyl acrylate, sodium dodecyl sulfate and potassium persulfate in a mass ratio of 8:2:0.5:0.1, reacting at 85° C. for 5 h under a nitrogen atmosphere, filtering, washing and drying to obtain modified silica particles;

[0063] S4, according to the above mass fractions, the modified silicon dioxide particles and other ingredients are mixed and stirred uniformly, added into an extruder, extruded at 200-300° C., and subjected to inflation treatment (inflation ratio of 2) to obtain a heat shrinkable layer tube sleeve;

[0064] S5. Insert the tube core containing the substrate, the primer layer, the silicone layer and the top layer into the heat shrinkable layer tube sleeve, and heat at 300-310° C. for 4 minutes to obtain a product.

[0065] Comparative Example 1

[0066] A fixing film with a heat shrinking effect. The difference between this comparative example and Example 1 is that the modified silica particles are replaced by a mixture of hydroxylated silica and perfluoroheptanoic acid in a mass ratio of 2:1, and other materials and preparation methods are the same as those in Example 1.

[0067] Comparative Example 2

[0068] A fixing film with a heat shrinking effect. The difference between this comparative example and Example 1 is that in step S1, all perfluoroheptanoic acid is replaced by acrylic acid, and other materials and preparation methods are the same as those in Example 1.

[0069] Test Case

[0070] The performance test was performed on the fixing films with heat shrinkage effect prepared in Examples 1-3 and Comparative Examples 1-2.

[0071] Test method:

[0072] Mechanical properties: Tested in accordance with GB / T 13022.

[0073] Surface smoothness: observe whether there are bubbles and wrinkles on the surface of the fixing film samples prepared in the examples and comparative examples; then perform a printing test to check whether the printed samples are uniform and clear.

[0074] The test results are shown in Table 1.

[0075] Table 1 Performance test results

[0076]

[0077] According to Table 1, it can be concluded that the fixing films with heat shrinking effect prepared in Examples 1-3 of the present invention have good mechanical properties, avoid defects such as bubbles and wrinkles, and have excellent fixing performance; while in Comparative Example 1-2, since the modified silica is replaced by a physical mixture of unmodified silica and perfluoro acid or acrylic acid-modified silica, the compatibility between the components is reduced, it is difficult to form an ideal synergistic effect, the uniformity and stability of the cross-linked structure are reduced, resulting in a decrease in the mechanical properties of the material, the heat shrinking effect is not uniform enough, the fixing film has defects such as bubbles, and the clarity of the printed sample is significantly reduced. In summary, the present invention overcomes the problems existing in the prior art and has good application prospects.

[0078] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0079] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A fixing film with heat shrinking effect, characterized in that: The fixing film has a multi-layer structure, which includes, from inside to outside, a substrate, a primer layer, a silicone layer, a topcoat layer and a heat shrinkable layer; The heat shrinkable layer comprises the following components in parts by weight: The modified silicon dioxide particles are the product of hydroxylated silicon dioxide, silicon dioxide partially grafted with perfluorinated acid and partially grafted with unsaturated carboxylic acid, and then copolymerized with acrylate.

2. The fixing film with heat shrinking effect according to claim 1, characterized in that: The perfluoro acid is selected from one or more of perfluorotridecanoic acid, perfluorohexanoic acid, perfluoroheptanoic acid or a mixture thereof.

3. The fixing film with heat shrinking effect according to claim 1, characterized in that: The unsaturated carboxylic acid is selected from one or more of acrylic acid and methacrylic acid.

4. The fixing film with heat shrinking effect according to claim 1, characterized in that: The acrylate is selected from one or more of butyl acrylate, octyl acrylate, and dodecyl acrylate.

5. The method for preparing a fixing film having a heat shrinking effect according to any one of claims 1 to 4, characterized in that: The method for preparing the fixing film with heat shrinking effect comprises the following steps: S1, blending a perfluoro acid and an unsaturated acid, adding a solvent, and stirring to form a blend; S2, immersing hydroxylated silicon dioxide in the blend, ultrasonically heating, and reacting to form an intermediate product; S3, subjecting the intermediate product to free radical polymerization with acrylate to form modified silica particles; S4, mixing the modified silicon dioxide particles and other ingredients, and extruding to obtain a heat shrinkable layer tube sleeve; S5, inserting the tube core containing the substrate, the primer layer, the silicone layer and the top layer into the heat shrinkable layer tube sleeve to obtain a product.

6. The method for preparing a fixing film with heat shrinkage effect according to claim 5, characterized in that: The molar ratio of the perfluoro acid to the unsaturated carboxylic acid is 1:(1-3).

7. The method for preparing a fixing film with heat shrinkage effect according to claim 5, characterized in that: The temperature of the ultrasonic heating is 60-90°C.

8. The method for preparing a fixing film with heat shrinkage effect according to claim 5, characterized in that: The mass ratio of the intermediate product to the acrylic ester is (0.1-5):

1.

9. The method for preparing a fixing film with heat shrinkage effect according to claim 5, characterized in that: The temperature of the free radical polymerization is 50-100°C.

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