Photographic base paper, photographic paper base and photographic paper

Abstract

The invention provides photographic base paper, a photographic paper base and photographic paper. The photographic base paper comprises a base paper body and two conductive layers, wherein the two conductive layers are oppositely arranged on the surfaces of the two sides of the base paper body; the conductive layer includes an organic salt. Therefore, in the photographic base paper, the two conductive layers containing the organic salt are oppositely arranged on the surfaces of the two sides of the base paper body, so that the conductive performance of the paper is effectively improved, electrostatic accumulation is reduced, electrostatic spots are avoided, the photo quality is improved, and meanwhile, the stability and environmental friendliness of the paper are ensured.

Description

Technical Field

[0001] The present application belongs to the field of photographic printing technology, and in particular, relates to a photographic base paper, a photographic paper base and a photographic paper. Background Art

[0002] Color photographic paper is formed by coating plastic-coated paper base, which is produced by compounding polyethylene (PE) on both sides of base paper. Therefore, base paper is an indispensable raw material for producing color photographic paper. During the coating, cutting and use of color photographic paper, static electricity is often generated on the paper due to the friction between the paper and the contact object. When the charged paper is close to the conductor, discharge will occur, thus generating static electricity sparks, making the silver salt emulsion layer abnormally sensitive to light, thus generating the defect of "static spots". "Static spots" seriously affect the image quality of photos, and this problem is particularly serious in the dry winter.

[0003] At present, the commonly used method to reduce static sparks is to add inorganic salts that enhance conductivity to the base paper. Patent CN117626716A mentions that sodium salts are used as antistatic agents and lithium salts are used as hygroscopic agents. The use of sodium salts and lithium salts at the same time can effectively reduce the surface resistance of the paper base, thereby improving its conductivity and reducing the impact of static electricity. However, this method has several problems. First, in order to make the base paper obtain good conductivity, a large amount of inorganic salts need to be used in the base paper, but this will cause the base paper to produce a large amount of salt-containing wastewater during the recycling process, which will put pressure on the environment; on the other hand, in order to improve the conductivity of the base paper in the patent, the added inorganic salts need to be enriched on the surface of the base paper as much as possible, but when small molecule inorganic salts are added to the base paper, the problem of migration from the surface to the inside will occur during the storage of the base paper, resulting in a decrease in the conductivity of the base paper, and the photo paper cannot obtain sufficient antistatic properties. Summary of the invention

[0004] The present application aims to solve at least one of the technical problems existing in the prior art to a certain extent. To this end, the present application provides a photographic base paper, a photographic paper base and a photographic paper, wherein the photographic base paper significantly reduces the friction voltage and avoids the generation of static sparks by arranging conductive layers on both sides of the base paper body, while maintaining environmental friendliness and wet processing performance and ensuring the stability of conductivity.

[0005] In one aspect of the present application, a photographic base paper is provided. According to an embodiment of the present application, the photographic base paper comprises: a base paper body and two conductive layers, the two conductive layers are arranged oppositely on two side surfaces of the base paper body; the conductive layers comprise organic salts.

[0006] Therefore, in the photographic base paper of the present application, by arranging two conductive layers containing organic salts on the two side surfaces of the base paper body, the conductive performance of the paper is effectively improved, thereby reducing static electricity accumulation, avoiding the generation of static electricity spots, improving the quality of photos, and ensuring the stability and environmental friendliness of the paper.

[0007] In addition, the photographic base paper according to the above embodiment of the present application may also have the following additional technical features:

[0008] According to an embodiment of the present application, the organic salt includes at least one of sodium carboxymethyl starch, sodium carboxymethyl cellulose, and sodium polystyrene sulfonate.

[0009] According to an embodiment of the present application, the conductive layer further includes at least one of a surfactant, a fluorescent whitening agent, starch, an inorganic salt and water.

[0010] According to an embodiment of the present application, the conductive layer includes: 10 to 20 parts by weight of an organic salt; 60 to 80 parts by weight of water; 0.1 to 1 parts by weight of a surfactant; 0.1 to 1 parts by weight of a fluorescent whitening agent; 0 to 2 parts by weight of starch; and 0 to 2 parts by weight of an inorganic salt.

[0011] According to an embodiment of the present application, the surface resistance of the photographic base paper is not greater than 10 10 Ω.

[0012] According to an embodiment of the present application, the thickness of the conductive layer is 1 to 10 μm.

[0013] According to an embodiment of the present application, the surfactant includes at least one of a polyethylene oxide ether type nonionic surfactant and a betaine type surfactant.

[0014] According to an embodiment of the present application, the fluorescent whitening agent includes at least one of a triazine aminostilbene type fluorescent whitening agent, an oxazole ring type fluorescent whitening agent, and a diacetylamino substituted fluorescent whitening agent.

[0015] According to an embodiment of the present application, the inorganic salt includes at least one of sodium chloride, lithium chloride, magnesium chloride, and calcium chloride.

[0016] In another aspect of the present application, the present application provides a photographic paper base. According to an embodiment of the present application, the photographic paper base comprises the above-mentioned photographic base paper.

[0017] Those skilled in the art will appreciate that the features and advantages described above for photographic base paper are also applicable to the photographic paper base, and will not be described in detail herein.

[0018] According to an embodiment of the present application, one of the two conductive layers is provided with a resin layer and a bottom layer in sequence on a side away from the base paper body, and the other of the two conductive layers is provided with a resin layer and an antistatic layer in sequence on a side away from the base paper body.

[0019] According to an embodiment of the present application, the resin layer includes at least one of polyethylene, polypropylene, and polyvinyl chloride.

[0020] According to an embodiment of the present application, the thickness of the resin layer is 10 to 30 μm.

[0021] According to an embodiment of the present application, the antistatic layer includes at least one of alkyl sulfonate, sulfate, betaine, sodium polystyrene sulfonate and sodium polyethylene sulfonate.

[0022] According to an embodiment of the present application, the bottom layer includes gelatin.

[0023] In another aspect of the present application, the present application provides a photographic paper. According to an embodiment of the present application, the photographic paper comprises at least one of the above-mentioned photographic base paper and the above-mentioned photographic paper base.

[0024] Those skilled in the art will appreciate that the features and advantages described above for the photographic paper base are also applicable to the photographic paper, and will not be described in detail herein.

[0025] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0027] Figure 1 This is a schematic diagram of the structure of a photographic base paper in one embodiment of the present application;

[0028] Figure 2 It is a schematic diagram of the structure of a photographic paper base in one embodiment of the present application. DETAILED DESCRIPTION

[0029] The embodiments of the present application are described in detail below. The embodiments described below are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0030] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. Further, in the description of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0031] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0032] In this document, the terms "include" or "comprising" are open expressions, that is, including the contents specified in the present application but not excluding other contents.

[0033] As used herein, the terms "optionally", "optional" or "optionally" generally mean that the subsequently described event or circumstance may but need not occur, and that the description includes instances where the event or circumstance occurs and instances where it does not.

[0034] Photographic paper base

[0035] In one aspect of the present application, the present application provides a photographic base paper. According to an embodiment of the present application, referring to Figure 1 The photographic base paper comprises: a base paper body and two conductive layers, wherein the two conductive layers are arranged on two side surfaces of the base paper body opposite to each other; and the conductive layers comprise organic salts.

[0036] As an example, in the present application, the base paper body may include hardwood pulp.

[0037] Therefore, in the photographic base paper of the present application, by arranging two conductive layers containing organic salts on the two side surfaces of the base paper body, the conductive performance of the paper is effectively improved, thereby reducing static electricity accumulation, avoiding the generation of static electricity spots, improving the quality of photos, and ensuring the stability and environmental friendliness of the paper.

[0038] According to an embodiment of the present application, the organic salt includes at least one of sodium carboxymethyl starch (CMS), sodium carboxymethyl cellulose (CMC), and sodium polystyrene sulfonate (PSS). Thus, the organic salt can form a stable conductive layer on the surface of the base paper, significantly improve the conductivity of the base paper, and reduce static electricity problems. At the same time, due to its macromolecular structure, it is not easy to migrate in the paper, ensuring the long-term stability of the conductive performance, thereby improving the antistatic performance and image quality of the photographic paper base.

[0039] According to an embodiment of the present application, the conductive layer further includes at least one of a surfactant, a fluorescent whitening agent, starch, an inorganic salt and water. Thus, the surfactant reduces the surface tension in the conductive layer and improves the coating uniformity; the fluorescent whitening agent enhances the whiteness and brightness of the paper and improves the visual effect; the starch acts as a binder and filler to enhance the adhesion and uniformity of the coating; the inorganic salt plays a role in assisting in enhancing the conductive performance, and acts together with the organic salt to improve the overall conductive efficiency of the photographic base paper and further reduce the accumulation of static electricity; the water acts as a solvent to help dissolve the dispersed components and jointly improve the stability, uniformity and conductivity of the photographic base paper.

[0040] According to an embodiment of the present application, the conductive layer includes: 10 to 20 parts by weight of an organic salt, for example, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20; 60 to 80 parts by weight of water, for example, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80; 0.1 to 1 part by weight of a surfactant, for example, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1; 0.1 to 1 part by weight of a fluorescent whitening agent, for example, 0.1, 0 0-2 parts by weight of starch, for example, 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1; 0-2 parts by weight of inorganic salt, for example, 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0. Thus, the stability, uniformity and conductivity of the photographic base paper are further improved.

[0041] According to an embodiment of the present application, the surface resistance of the photographic base paper is not greater than 10 10 Ω. As a result, the photographic base paper has sufficient conductivity to effectively prevent static electricity accumulation and reduce static spot phenomenon

[0042] According to an embodiment of the present application, the thickness of the conductive layer is 1-10 μm, for example, 1 μm, 1.5 μm, 2 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm, 6.5 μm, 7 μm, 7.5 μm, 8 μm, 8.5 μm, 9 μm, 9.5 μm, 10 μm. Thus, while maintaining the feel and processing performance of the paper, the surface resistance is effectively reduced, the accumulation of static electricity is reduced, and the printing quality and image clarity of the photo are improved.

[0043] According to an embodiment of the present application, the surfactant includes at least one of a polyethylene oxide ether type nonionic surfactant and a betaine type surfactant, thereby reducing the surface tension in the conductive layer and improving the coating uniformity.

[0044] According to an embodiment of the present application, the fluorescent whitening agent includes at least one of a triazine amino diphenylethylene type fluorescent whitening agent, an oxazole ring type fluorescent whitening agent, and a diacetylamino substituted type fluorescent whitening agent, thereby enhancing the whiteness and brightness of the paper and improving the visual effect.

[0045] According to an embodiment of the present application, the inorganic salt includes at least one of sodium chloride, lithium chloride, magnesium chloride, and calcium chloride, thereby assisting in enhancing the conductivity of the conductive layer and further reducing static electricity accumulation.

[0046] In another aspect of the present application, the present application provides a photographic paper base. According to an embodiment of the present application, the photographic paper base comprises the above-mentioned photographic base paper.

[0047] According to the embodiments of the present application, referring to Figure 2 , the photographic paper base can further include: a bottom layer, a resin layer, a conductive layer, a base paper body, a conductive layer, a resin layer, and an antistatic layer; one of the two conductive layers is provided with a resin layer and a bottom layer in sequence on a side away from the base paper body, and the other of the two conductive layers is provided with a resin layer and an antistatic layer in sequence on a side away from the base paper body. Thus, a composite structure photographic paper base is formed, wherein the resin layer prevents edge seepage during the later wet processing, the bottom layer enhances the physical strength and water resistance of the photographic paper base, and the antistatic layer effectively reduces static electricity accumulation through its conductive properties, thereby protecting the image quality and the stability of the printing process.

[0048] According to an embodiment of the present application, the resin layer includes at least one of polyethylene, polypropylene, and polyvinyl chloride, thereby preventing edge seepage during later wet processing.

[0049] According to an embodiment of the present application, the thickness of the resin layer is 10 to 30 μm, for example, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, 27 μm, 28 μm, 29 μm, 30 μm. Thus, by precisely adjusting the thickness of the resin layer, the surface characteristics of the paper base can be optimized, the clarity and quality of the printed image can be improved, while maintaining the processing and use performance of the paper base, ensuring its reliability and durability in various printing and post-processing applications.

[0050] According to an embodiment of the present application, the antistatic layer includes at least one of alkyl sulfonate, sulfate, betaine, sodium polystyrene sulfonate and sodium polyvinyl sulfonate, thereby effectively reducing static electricity accumulation through its conductive properties, protecting image quality and stability of the printing process.

[0051] According to an embodiment of the present application, the bottom layer includes gelatin, thereby providing stability for the photographic paper base, while enhancing the moisture resistance and chemical resistance of the paper base, ensuring the clarity and long-term preservation of the printed image.

[0052] In another aspect of the present application, the present application provides a photographic paper. According to an embodiment of the present application, the photographic paper comprises at least one of the above-mentioned photographic base paper and the above-mentioned photographic paper base.

[0053] Those skilled in the art will appreciate that the features and advantages described above for the photographic base paper are also applicable to the photographic paper, and will not be described in detail herein.

[0054] The scheme of the present application will be explained below in conjunction with the embodiments. It will be appreciated by those skilled in the art that the following embodiments are only used to illustrate the present application and should not be considered as limiting the scope of the present application. If no specific technology or conditions are indicated in the embodiments, the technology or conditions described in the literature in this area or the product specification are carried out. The reagents used or the instruments that do not indicate the manufacturer are all conventional products that can be obtained commercially.

[0055] The surfactant is surfactant 1292 purchased from Lucky Chemical; the fluorescent brightener is fluorescent brightener SPF purchased from Takemoto Chemical.

[0056] Embodiment 1:

[0057] In this embodiment, base paper made of broadleaf wood pulp is used, the bottom layer is made of gelatin coating, and the antistatic layer is formed by coating with betaine BS-12 antistatic liquid. The base paper is coated with conductive layer coating liquid on both sides to form two conductive layers.

[0058] Furthermore, high-density polyethylene (HDPE) resin and a bottom layer are sequentially coated on one side of the conductive layer away from the base paper, and resin and an antistatic layer are sequentially coated on another conductive layer. The thickness of the conductive layer is 1.5 μm, and the thickness of the resin layer is 26 μm. The resin layer is melt-coated at 300°C. The antistatic layer is coated with 0.1 μm using a micro-gravure and dried at 100°C for 1 minute.

[0059] The differences between Examples 2 to 5 and Comparative Examples 1 to 2 and Example 1 are shown in Table 1.

[0060] Table 1. Conductive layer formulation

[0061]

[0062] Comparative Example 3

[0063] The difference between Comparative Example 3 and Example 1 is that no conductive layer is provided, and the base paper layer has the following composition: 90 wt % of hardwood pulp, 5 wt % of sodium chloride, 0.01 wt % of lithium chloride, and 3 wt % of alkyl ketene dimer.

[0064] Comparative Example 4

[0065] The difference between Comparative Example 4 and Comparative Example 3 is that 10 g of CMC is added to the base paper layer.

[0066] Comparative Example 5

[0067] The difference between Comparative Example 5 and Example 5 is that lithium nitrate is added to the antistatic layer coating liquid, and no conductive layer is provided.

[0068] Comparative Example 6

[0069] The difference between Comparative Example 6 and Example 5 is that no conductive layer is provided.

[0070] Test Case

[0071] 1. After the conductive layer was coated on both sides of the base paper of Examples 1 to 5 and Comparative Examples 1 to 4, the surface resistance of the base paper was tested using an SL-030 surface resistance meter; the test was performed again after 7 days.

[0072] After further coating, bottom layer and antistatic layer, the friction voltage of the paper base is measured. The friction voltage test is as follows:

[0073] Test conditions: temperature at 25±1℃, humidity at 50±2%RH.

[0074] Place the paper substrate to be tested in the test environment for more than 2 hours in a balanced manner. Use an AGFA coating tester and an electrostatic field tester to test the friction static electricity of the paper substrate at a speed of 70 m / min, and use the maximum voltage as the recorded data.

[0075] The test results are shown in Table 2. By comparing Example 5 with Comparative Example 1, it can be seen that the surface resistance of the base paper can be significantly improved and the conductivity can be enhanced after coating the organic macromolecules on both sides of the base paper. By comparing Example 5 with Comparative Example 2, it can be seen that the surface resistance of the base paper coated with small molecule inorganic salts on the surface changes after being placed for 7 days. The surface resistance of the base paper is unstable due to the migration of small molecule inorganic salts, while the surface resistance of the base paper coated with macromolecular organic salts on the surface does not change after being placed for 7 days. Comparative Example 3 uses inorganic salts in the base paper to improve the conductivity. On the one hand, it causes the base paper to produce a large amount of salt-containing wastewater during the recycling process, which puts pressure on the environment. On the other hand, during the storage of the base paper, the problem of inorganic salts migrating from the surface to the inside will occur, resulting in a decrease in the conductivity of the base paper, and the photo paper cannot obtain sufficient antistatic properties. Comparative Example 1 and Comparative Example 4 can be compared. Compared with the method of directly adding organic salts to the base paper, the embodiment of the present application reduces the use of inorganic salts in the base paper by coating organic salts on both sides of the base paper as a conductive layer, and more effectively improves the surface resistance, thereby providing a better antistatic effect.

[0076] Table 2. Surface resistance of base paper and friction voltage of paper base

[0077]

[0078]

[0079] 2. The test methods of Example 5 and Comparative Examples 5-6 are the same as those of Test Example 1, and the surface resistance of the antistatic layer, the surface resistance of the base paper, and the friction voltage are tested respectively. The results are shown in Table 3. It can be seen from Comparative Examples 5 and 6 that the friction voltage of the photographic paper cannot be significantly reduced by only improving the conductivity of the antistatic layer, because the static electricity accumulated in the antistatic layer of the photographic paper cannot be discharged to the environment. By comparing Example 5 and Comparative Examples 5-6, it can be seen that coating the surface of the base paper with a macromolecular salt antistatic agent can effectively improve the conductivity of the photographic base paper, thereby significantly reducing the friction voltage of the photographic paper during use. After improving the conductivity of the base paper, the capacitance effect between the antistatic layer and the conductive base paper can effectively improve the friction voltage, avoid static sparks caused by cutting the photographic paper in a dry environment, and protect the photographic paper from static exposure. In addition, coating the surface of the base paper with macromolecular salt substances has no effect on the edge permeability during wet processing.

[0080] Table 3. Effect of antistatic layer and base paper conductivity on paper base friction voltage

[0081]

[0082] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0083] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A photographic base paper, characterized in that: include: A base paper body and two conductive layers, wherein the two conductive layers are arranged on two side surfaces of the base paper body opposite to each other; The conductive layer includes an organic salt.

2. The photographic base paper according to claim 1, characterized in that: The organic salt includes at least one of sodium carboxymethyl starch, sodium carboxymethyl cellulose, and sodium polystyrene sulfonate.

3. The photographic base paper according to claim 1, characterized in that: The conductive layer further includes at least one of a surfactant, a fluorescent whitening agent, starch, an inorganic salt and water.

4. The photographic base paper according to claim 1, characterized in that: The conductive layer comprises: 10 to 20 parts by weight of an organic salt; 60-80 parts by weight of water; 0.1 to 1 parts by weight of a surfactant; 0.1 to 1 parts by weight of fluorescent whitening agent; 0 to 2 parts by weight of starch; 0 to 2 parts by weight of inorganic salt.

5. The photographic base paper according to claim 1, characterized in that: The surface resistance of the photographic base paper is not greater than 10 10 Ω; Optionally, the conductive layer has a thickness of 1 to 10 μm.

6. The photographic base paper according to claim 4, characterized in that: The surfactant includes at least one of a polyethylene oxide ether type nonionic surfactant and a betaine type surfactant; Optionally, the fluorescent whitening agent includes at least one of a triazine aminostilbene type fluorescent whitening agent, an oxazole ring type fluorescent whitening agent, and a diacetylamino substituted fluorescent whitening agent; Optionally, the inorganic salt includes at least one of sodium chloride, lithium chloride, magnesium chloride and calcium chloride.

7. A photographic paper base, characterized in that include: The photographic base paper according to any one of claims 1 to 6.

8. The photographic paper base according to claim 7, characterized in that A resin layer and a bottom layer are sequentially arranged on a side of one of the two conductive layers away from the base paper body, and a resin layer and an antistatic layer are sequentially arranged on a side of the other of the two conductive layers away from the base paper body.

9. The photographic paper base according to claim 8, characterized in that The resin layer includes at least one of polyethylene, polypropylene, and polyvinyl chloride; Optionally, the thickness of the resin layer is 10 to 30 μm; Optionally, the antistatic layer comprises at least one of alkyl sulfonate, sulfate, betaine, sodium polystyrene sulfonate and sodium polyethylene sulfonate; Optionally, the bottom layer comprises gelatin.

10. A photographic paper, characterized in that: The invention comprises at least one of the photographic base paper according to any one of claims 1 to 6 and the photographic paper base according to any one of claims 7 to 9.

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