Preparation method of calcium carbonate hollow microspheres for deacidification and reinforcement of ancient archive paper

Abstract

The invention discloses a preparation method of calcium carbonate hollow microspheres for deacidification and reinforcement of ancient archive paper, which comprises the following steps: (1) respectively preparing a lauryl sodium sulfate solution and a sodium carboxymethyl cellulose solution, firstly carrying out ultrasonic treatment on the lauryl sodium sulfate solution, and uniformly mixing the two solutions under the stirring condition to obtain a solution A; a sodium dodecyl sulfate-sodium carboxymethyl cellulose solution is obtained; (2) adding a calcium chloride solution, and performing ultrasonic treatment; (3) adding a sodium carbonate solution, and after the reaction is completed, centrifuging, washing and drying to obtain calcium carbonate hollow microspheres; (4) placing the calcium carbonate hollow microspheres in a sodium hydroxide solution; and (5) taking CMC as a solvent and the calcium carbonate hollow microspheres as a solute, and mixing to obtain the calcium carbonate hollow microspheres for deacidifying and reinforcing the paper. The method is easy to operate, the obtained calcium carbonate microspheres are uniform in particle and have a good deacidification effect, the treated paper shows certain alkalinity and ageing resistance, the durability of the paper is improved, and the service life of the paper is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of restoration and protection of paper cultural relics, and in particular to a method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper. Background Art

[0002] Calcium carbonate has abundant reserves in nature and is widely used in industrial production in industry and daily life. With the advancement of science and technology and the needs of various industries, the role of traditional calcium carbonate morphology is no longer enough. Stimulated by social needs and the advancement of theoretical knowledge, how to prepare calcium carbonate particles with different morphologies based on the understanding of the formation mechanism of calcium carbonate has become a key research direction. Nowadays, scientific researchers are constantly exploring the unique role of calcium carbonate with various morphologies in the production of various industries, which has also led to the long-term development of research on the preparation of calcium carbonate with special morphologies.

[0003] Hollow calcium carbonate microspheres have a unique structure. Compared with solid microspheres of the same particle size, hollow calcium carbonate microspheres have the advantages of lower density, larger specific surface area, and the internal cavity can load other substances. With these advantages, hollow calcium carbonate microspheres have potential application prospects in the fields of electronics, materials science, chemistry and medicine.

[0004] Paper acidification is an important factor affecting the life of paper. At present, the best way to protect paper is to deacidify the acidified paper, neutralize the acid in the paper with alkaline substances, and retain a part of the acid in the paper to prevent the phenomenon of acid regurgitation. At the same time, it can also continuously neutralize the acid components in the paper caused by the surrounding environment. At present, the common deacidification methods for paper include liquid phase deacidification and gas phase deacidification, but there are certain disadvantages, such as poor deacidification effect and acid regurgitation. At the same time, in the operation of deacidification of paper, it is inevitable that the paper will be damaged to a certain extent. Therefore, the reinforcement and deacidification of paper must be carried out at the same time to extend the life of the paper as much as possible. However, in the process of deacidification and reinforcement of paper, how to overcome the difficulties such as the instability of reinforcement materials, the expensive deacidification agent, the toxicity of reinforcement materials, and the cumbersome operation is an urgent problem to be solved. Summary of the invention

[0005] In view of this, the present invention provides a method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archival paper.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] The preparation method of calcium carbonate hollow microspheres for deacidification and reinforcement of ancient book and archive paper comprises the following steps:

[0008] (1) preparing a sodium dodecyl sulfate solution and a sodium carboxymethyl cellulose solution respectively, first subjecting the sodium dodecyl sulfate solution to ultrasonic treatment, and then mixing the two solutions under stirring to obtain a sodium dodecyl sulfate-sodium carboxymethyl cellulose solution;

[0009] (2) adding the calcium chloride solution to the sodium dodecyl sulfate-sodium carboxymethyl cellulose solution and performing ultrasonic treatment;

[0010] (3) adding sodium carbonate solution to the solution obtained in step (2), and after the reaction is completed, centrifuging, washing, and drying to obtain hollow calcium carbonate microspheres;

[0011] (4) placing the calcium carbonate hollow microspheres in a sodium hydroxide solution;

[0012] (5) CMC is used as a solvent and hollow calcium carbonate microspheres are used as a solute, and the mixture is mixed in proportion to obtain hollow calcium carbonate microspheres for deacidification and reinforcement of paper.

[0013] Preferably, in step (1), the mass concentration of the sodium dodecyl sulfate solution is 1 g / L-10 g / L, and the mass concentration of the sodium carboxymethyl cellulose solution is 1 g / L-10 g / L.

[0014] Preferably, the molar concentration of calcium chloride in step (2) is 0.1 mol / L-1 mol / L.

[0015] Preferably, in step (1), the stirring time is 0.5-2 h, and the stirring temperature is room temperature; in step (1) and step (2), the ultrasonic treatment time is 10 min-40 min.

[0016] Preferably, in step (3), the reaction temperature is 20°C-80°C.

[0017] Preferably, in step (3), the molar concentration of sodium carbonate is 0.1 mol / L-2 mol / L.

[0018] Preferably, the molar concentration of sodium hydroxide in step (4) is 0.1 mol / L-1 mol / L.

[0019] Preferably, in step (5), the mass concentration of CMC is 1 g / L-10 g / L, and the ratio of hollow calcium carbonate microspheres to sodium carboxymethyl cellulose is (2-8):1000.

[0020] The preparation method of calcium carbonate hollow microspheres for deacidification and reinforcement of ancient book and archival paper is applied in deacidification and reinforcement microcapsules.

[0021] Preferably, the specific application method is: spray the deacidified reinforcement microcapsules evenly onto the surface of the paper document in the form of a spray, and then place the paper in a constant temperature and humidity chamber with a temperature of 20-24° C. and a relative humidity of RH30-52% to dry for 24-48 hours.

[0022] Compared with the prior art, the present invention has achieved the following technical effects:

[0023] (1) The pH of the paper treated by the present invention is in an optimal range, and the treated paper is alkaline and the mechanical properties of the paper are improved by 15%-30%. The paper also has a higher reserve alkali content, and the life of the paper is also greatly improved.

[0024] (2) The deacidification and reinforcement microcapsules prepared by the present invention are safe and environmentally friendly, harmless to paper quality and storage environment, and also improve problems such as paper wrinkling during the deacidification and reinforcement process. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a SEM image of the calcium carbonate hollow microspheres prepared by the method for preparing the calcium carbonate hollow microspheres for deacidification and reinforcement of ancient book and archive paper of the present invention;

[0026] Figure 2 This is an enlarged SEM image of the calcium carbonate hollow microspheres prepared by the method for preparing the calcium carbonate hollow microspheres for deacidification and reinforcement of ancient book and archive paper of the present invention;

[0027] Figure 3 This is a SEM image of unprotected paper produced by the method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper of the present invention;

[0028] Figure 4 This is a SEM image of paper treated with dry heat aging without protection treatment in the preparation method of hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper of the present invention;

[0029] Figure 5 This is a SEM image of paper treated with protection in the preparation method of hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper of the present invention;

[0030] Figure 6 This is a SEM image of paper that has been protected and treated with dry heat aging and is prepared by the method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archival paper of the present invention. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] The invention discloses a method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper, comprising the following steps:

[0033] (1) respectively preparing a sodium dodecyl sulfate solution with a mass concentration of 1 g / L-10 g / L and a sodium carboxymethyl cellulose solution with a mass concentration of 1 g / L-10 g / L, firstly subjecting the sodium dodecyl sulfate solution to ultrasonic treatment for 10 min-40 min, stirring at room temperature for 0.5-2 h, and mixing the two solutions uniformly under stirring to obtain a sodium dodecyl sulfate-sodium carboxymethyl cellulose solution;

[0034] (2) adding a calcium chloride solution with a molar concentration of 0.1 mol / L–1 mol / L to the sodium dodecyl sulfate-sodium carboxymethyl cellulose solution and ultrasonically treating for 10 min–40 min;

[0035] (3) adding sodium carbonate solution to the solution obtained in step (2), reacting at 20° C. to 80° C., and after the reaction is completed, centrifuging, washing, and drying to obtain calcium carbonate hollow microspheres;

[0036] (4) placing calcium carbonate hollow microspheres with a molar concentration of 0.1 mol / L–2 mol / L in a sodium hydroxide solution with a molar concentration of 0.1 mol / L–1 mol / L;

[0037] (5) Using CMC with a mass concentration of 1 g / L–10 g / L as a solvent and hollow calcium carbonate microspheres as a solute, the ratio of hollow calcium carbonate microspheres to sodium carboxymethyl cellulose (2-8):1000 was used to obtain hollow calcium carbonate microspheres for deacidification and reinforcement of paper.

[0038] The preparation method of calcium carbonate hollow microspheres for deacidification and reinforcement of ancient book and archival paper is applied in deacidification and reinforcement microcapsules.

[0039] The specific application method is: spray the deacidification reinforcement microcapsules evenly onto the surface of paper documents in the form of spray, and then place the paper in a constant temperature and humidity room with a temperature of 20-24°C and a relative humidity of RH30-52% to dry for 24-48 hours.

[0040] Embodiment 1:

[0041] (1) adding 0.4 g of sodium dodecyl sulfate to 100 g of water, stirring the mixture under mechanical stirring to obtain solution 1; adding 0.1 g of sodium carboxymethyl cellulose to 100 g of water, stirring the mixture under mechanical stirring to obtain solution 2; mixing solution 1 and solution 2 to obtain solution 3; subjecting solution 3 to ultrasonic treatment for 15 min;

[0042] (2) 2.22 g of calcium chloride was added to 200 g of water to obtain solution 4. Solution 3 was slowly added to solution 4 at 40° C. to obtain solution 5, which was then ultrasonically treated for 15 min.

[0043] (3) 2.12 g of sodium carbonate was added to 200 g of water to obtain solution 6. Solution 5 was slowly added to solution 6 at 40° C., and the mixture was centrifuged, washed, and dried to obtain hollow calcium carbonate spheres.

[0044] (4) The hollow calcium carbonate microspheres are placed in a 0.5 mol / L sodium hydroxide solution for adsorption treatment.

[0045] (5) mixing the obtained calcium carbonate hollow spheres with 4 g / L sodium carboxymethyl cellulose solution at a mass ratio of 8:1000 to obtain deacidified and reinforced microcapsules;

[0046] (6) The obtained deacidified reinforced microcapsules are transferred to a spray bottle at room temperature and sprayed on the hanging paper; then, the samples are placed in a constant temperature and humidity environment at a temperature of (23±1)°C and a relative humidity of (50±2)% to dry for 24 hours, and the pH value and mechanical properties of the paper are tested. The treated paper is subjected to dry heat aging treatment at 105°C±2°C for 72 hours, and the pH value and mechanical properties of the paper are tested.

[0047] Embodiment 2:

[0048] (1) adding 0.4 g of sodium dodecyl sulfate to 100 g of water, stirring the mixture under mechanical stirring to obtain solution 1; adding 0.1 g of sodium carboxymethyl cellulose to 100 g of water, stirring the mixture under mechanical stirring to obtain solution 2; mixing solution 1 and solution 2 to obtain solution 3; subjecting solution 3 to ultrasonic treatment for 15 min;

[0049] (2) 2.22 g of calcium chloride was added to 200 g of water to obtain solution 4. Solution 3 was slowly added to solution 4 at 80° C. to obtain solution 5, which was then ultrasonically treated for 15 min.

[0050] (3) 2.12 g of sodium carbonate was added to 200 g of water to obtain solution 6. Solution 5 was slowly added to solution 6 at 40° C., and the mixture was centrifuged, washed, and dried to obtain hollow calcium carbonate spheres.

[0051] (4) placing the calcium carbonate hollow microspheres into a 0.5 mol / L sodium hydroxide solution for adsorption treatment;

[0052] (5) mixing the obtained calcium carbonate hollow spheres with 4 g / L sodium carboxymethyl cellulose solution at a ratio of 4:1000 to obtain deacidified and reinforced microcapsules;

[0053] (6) The obtained deacidified reinforced microcapsules are transferred to a spray bottle at room temperature and sprayed on the hanging paper; then, the samples are placed in a constant temperature and humidity environment at a temperature of (23±1)°C and a relative humidity of (50±2)% to dry for 24 hours, and the pH value and mechanical properties of the paper are tested. The treated paper is subjected to dry heat aging treatment at 105°C±2°C for 72 hours, and the pH value and mechanical properties of the paper are tested.

[0054] Embodiment 3:

[0055] (1) adding 0.4 g of sodium dodecyl sulfate to 100 g of water, stirring the mixture under mechanical stirring to obtain solution 1; adding 0.1 g of sodium carboxymethyl cellulose to 100 g of water, stirring the mixture under mechanical stirring to obtain solution 2; mixing solution 1 and solution 2 to obtain solution 3; subjecting solution 3 to ultrasonic treatment for 15 min;

[0056] (2) 2.22 g of calcium chloride was added to 200 g of water to obtain solution 4. Solution 3 was slowly added to solution 4 at 40° C. to obtain solution 5, which was then ultrasonically treated for 15 min.

[0057] (3) 2.12 g of sodium carbonate was added to 200 g of water to obtain solution 6. Solution 5 was slowly added to solution 6 at 40° C., and the mixture was centrifuged, washed, and dried to obtain hollow calcium carbonate spheres.

[0058] (4) placing the calcium carbonate hollow microspheres into a 0.5 mol / L sodium hydroxide solution for adsorption treatment;

[0059] (5) mixing the obtained hollow calcium carbonate spheres with 4 g / L sodium carboxymethyl cellulose solution at a ratio of 2:1000 to obtain deacidified and reinforced microcapsules;

[0060] (6) The obtained deacidified reinforced microcapsules are transferred to a spray bottle at room temperature and sprayed on the hanging paper; then the samples are placed in a constant temperature and humidity environment at a temperature of (23±1)°C and a relative humidity of (50±2)% for 24 hours to dry, and the pH and mechanical properties of the paper are tested. The treated paper is subjected to dry heat aging treatment at 105°C±2°C for 72 hours and then the pH and mechanical properties of the paper are tested.

[0061] Embodiment 4:

[0062] (1) adding 0.4 g of sodium dodecyl sulfate to 100 g of water, stirring the mixture under mechanical stirring to obtain solution 1; adding 0.1 g of sodium carboxymethyl cellulose to 100 g of water, stirring the mixture under mechanical stirring to obtain solution 2; mixing solution 1 and solution 2 to obtain solution 3; subjecting solution 3 to ultrasonic treatment for 15 min;

[0063] (2) 2.22 g of calcium chloride was added to 200 g of water to obtain solution 4. Solution 3 was slowly added to solution 4 at 80° C. to obtain solution 5, which was then ultrasonically treated for 15 min.

[0064] (3) 2.12 g of sodium carbonate was added to 200 g of water to obtain solution 6. Solution 5 was slowly added to solution 6 at 80° C., and the mixture was centrifuged, washed, and dried to obtain hollow calcium carbonate spheres.

[0065] (4) placing the calcium carbonate hollow microspheres into a 0.5 mol / L sodium hydroxide solution for adsorption treatment;

[0066] (5) mixing the obtained calcium carbonate hollow spheres with 4 g / L sodium carboxymethyl cellulose solution at a ratio of 4:1000 to obtain deacidified and reinforced microcapsules;

[0067] (6) The obtained deacidified reinforced microcapsules are transferred to a spray bottle at room temperature and sprayed on the hanging paper; then, the samples are placed in a constant temperature and humidity environment at a temperature of (23±1)°C and a relative humidity of (50±2)% to dry for 24 hours, and the pH value and mechanical properties of the paper are tested. The treated paper is subjected to dry heat aging treatment at 105°C±2°C for 72 hours, and the pH value and mechanical properties of the paper are tested.

[0068] Comparative Example 1:

[0069] (1) adding 0.4 g of sodium dodecyl sulfate to 100 g of water, stirring the mixture under mechanical stirring to obtain solution 1; adding 0.1 g of sodium carboxymethyl cellulose to 100 g of water, stirring the mixture under mechanical stirring to obtain solution 2; mixing solution 1 and solution 2 to obtain solution 3; subjecting solution 3 to ultrasonic treatment for 15 min;

[0070] (2) 2.22 g of calcium chloride was added to 200 g of water to obtain solution 4. Solution 3 was slowly added to solution 4 at 40° C. to obtain solution 5, which was then ultrasonically treated for 15 min.

[0071] (3) 2.12 g of sodium carbonate was added to 200 g of water to obtain solution 6. Solution 5 was slowly added to solution 6 at 40° C., and the mixture was centrifuged, washed, and dried to obtain hollow calcium carbonate spheres.

[0072] (4) mixing the obtained hollow calcium carbonate spheres with 2 g / L sodium carboxymethyl cellulose solution at a ratio of 2:1000 to obtain deacidified and reinforced microcapsules;

[0073] (5) The obtained deacidified reinforced microcapsules are transferred to a spray bottle at room temperature and sprayed on the hanging paper; then the samples are placed in a constant temperature and humidity environment at a temperature of (23±1)°C and a relative humidity of (50±2)% for 24 hours, and the pH value and mechanical properties of the paper are tested. The treated paper is subjected to dry heat aging treatment at 105°C±2°C for 72 hours and then the pH value and mechanical properties of the paper are tested.

[0074] Comparative Example 2:

[0075] (1) adding 0.4 g of sodium dodecyl sulfate to 100 g of water, stirring the mixture under mechanical stirring to obtain solution 1; adding 0.1 g of sodium carboxymethyl cellulose to 100 g of water, stirring the mixture under mechanical stirring to obtain solution 2; mixing solution 1 and solution 2 to obtain solution 3; subjecting solution 3 to ultrasonic treatment for 15 min;

[0076] (2) 2.22 g of calcium chloride was added to 200 g of water to obtain solution 4. Solution 3 was slowly added to solution 4 at 40° C. to obtain solution 5, which was then ultrasonically treated for 15 min.

[0077] (3) 2.12 g of sodium carbonate was added to 200 g of water to obtain solution 6. Solution 5 was slowly added to solution 6 at 40° C., and the mixture was centrifuged, washed, and dried to obtain hollow calcium carbonate spheres.

[0078] (4) placing the calcium carbonate hollow microspheres into a 0.5 mol / L sodium hydroxide solution for adsorption treatment;

[0079] (5) mixing the obtained hollow calcium carbonate spheres with 2 g / L sodium carboxymethyl cellulose solution at a ratio of 2:1000 to obtain deacidified and reinforced microcapsules;

[0080] (6) The obtained deacidified reinforced microcapsules are transferred to a spray bottle at room temperature and sprayed on the hanging paper; then, the samples are placed in a constant temperature and humidity environment at a temperature of (23±1)°C and a relative humidity of (50±2)% to dry for 24 hours, and the pH value and mechanical properties of the paper are tested. The treated paper is subjected to dry heat aging treatment at 105°C±2°C for 72 hours, and the pH value and mechanical properties of the paper are tested.

[0081] The experimental results of the above examples and comparative examples are shown in Table 1.

[0082] Table 1:

[0083]

[0084] The test results show that, in the embodiments of the present invention, after the deacidification treatment of the paper, the pH value of the paper is alkaline, which can play a good protective role on the paper. At the same time, the alkali retention is 100mmol / kg-275mmol / kg, and the tensile index of the paper is also improved by 15%-30%. From the data analysis, compared with the comparative example, it can be concluded that after the treatment, the reinforcement effects of embodiment 1 and comparative example 1 are quite different, and after the treatment and aging, the embodiment has a higher alkali reserve. At the same time, compared with comparative example 2, there are certain differences in the pH, tensile index and alkali reserve of the paper after treatment. Especially after the treatment and aging, compared with the embodiment, the decline rate of the performance parameters of the comparative example is higher than the comparison parameters of the embodiment.

[0085] from Figure 1 It can be seen that the hollow calcium carbonate microspheres prepared in Example 1 are uniform in size and are spherical in shape, and can be well filled in the gaps between paper fibers; Figure 2 It can be seen that Figure 1 The local magnification shows the more obvious structural morphology of calcium carbonate hollow microspheres; Figure 3 It can be seen that the surface morphology of the paper without protection treatment shows large gaps between fibers and fiber breaks; Figure 4 It can be seen that after the dry heat aging treatment, the fiber breakage of the old paper is more serious, and the gaps between the fibers of the paper become larger, indicating that after the artificial dry heat aging treatment, the fibers of the paper are destroyed, causing the physical properties of the paper to decline; Figure 5 It can be seen that after the paper fiber is treated with the hollow calcium carbonate microspheres prepared in Example 1, part of the hollow calcium carbonate microspheres are adsorbed on the surface of the paper fiber, which plays a role in strengthening and deacidifying the fiber; Figure 6 It can be seen that after the hollow calcium carbonate microspheres prepared in Example 1 were treated and aged, the overall structure of the hollow calcium carbonate microspheres was not destroyed, and they were also adsorbed on the surface of the fibers, and the fibers of the paper were not obviously broken. At the same time, through the pH test of the paper, it can be seen that the microcapsules have a good protection and deacidification effect on the paper.

[0086] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper, characterized in that: The steps include: (1) preparing a sodium dodecyl sulfate solution and a sodium carboxymethyl cellulose solution respectively, first subjecting the sodium dodecyl sulfate solution to ultrasonic treatment, and then mixing the two solutions under stirring to obtain a sodium dodecyl sulfate-sodium carboxymethyl cellulose solution; (2) adding the calcium chloride solution to the sodium dodecyl sulfate-sodium carboxymethyl cellulose solution and performing ultrasonic treatment; (3) adding sodium carbonate solution to the solution obtained in step (2), and after the reaction is completed, centrifuging, washing, and drying to obtain hollow calcium carbonate microspheres; (4) placing the calcium carbonate hollow microspheres in a sodium hydroxide solution; (5) CMC is used as a solvent and hollow calcium carbonate microspheres are used as a solute, and the mixture is mixed in proportion to obtain hollow calcium carbonate microspheres for deacidification and reinforcement of paper.

2. The method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper according to claim 1, characterized in that: In the step (1), the mass concentration of the sodium dodecyl sulfate solution is 1 g / L-10 g / L, and the mass concentration of the sodium carboxymethyl cellulose solution is 1 g / L-10 g / L.

3. The method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper according to claim 1, characterized in that: The molar concentration of calcium chloride in step (2) is 0.1 mol / L-1 mol / L.

4. The method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper according to claim 1, characterized in that: In the step (1), the stirring time is 0.5-2h, and the stirring temperature is room temperature; in the step (1) and the step (2), the ultrasonic treatment time is 10min-40min.

5. The method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper according to claim 1, characterized in that: In the step (3), the reaction temperature is 20°C-80°C.

6. The method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper according to claim 1, characterized in that: In the step (3), the molar concentration of sodium carbonate is 0.1 mol / L-2 mol / L.

7. The method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper according to claim 1, characterized in that: The molar concentration of sodium hydroxide in step (4) is 0.1 mol / L-1 mol / L.

8. The method for preparing hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper according to claim 1, characterized in that: In the step (5), the mass concentration of CMC is 1 g / L-10 g / L, and the ratio of hollow calcium carbonate microspheres to sodium carboxymethyl cellulose is (2-8):1000.

9. Use of the preparation method of hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper according to any one of claims 1 to 8 in deacidification and reinforcement microcapsules.

10. The use of the preparation method of hollow calcium carbonate microspheres for deacidification and reinforcement of ancient book and archive paper according to claim 9 in deacidification and reinforcement microcapsules, characterized in that: The specific application method is: spray the deacidification reinforcement microcapsules evenly onto the surface of paper documents in the form of spray, and then place the paper in a constant temperature and humidity room with a temperature of 20-24°C and a relative humidity of RH30-52% to dry for 24-48 hours.

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