A method for improving softness and strength properties of facial tissue paper

Abstract

The application provides a method for improving softness and strength of facial tissue paper, and belongs to the technical field of household paper, and the method comprises the following steps: mixing polyamide epichlorohydrin resin, di-dodecanedioic acid diglyceride, glycerol-water solvent and wood pulp slurry, sequentially performing first defibration and papermaking to obtain a formed facial tissue paper base paper; the addition amount of the polyamide epichlorohydrin resin is 3-12 kg / t of the absolute dry pulp mass of the wood pulp slurry; and the addition amount of the di-dodecanedioic acid diglyceride is 2-8 kg / t of the absolute dry pulp mass of the wood pulp slurry. The method has low cost, simple formula and easy operation, and the prepared facial tissue paper has obvious improvement in softness and strength compared with the facial tissue paper prepared by using amino silicon oil as a softener in the prior art; in addition, the softness of the facial tissue paper can be obviously improved through embossing.

Description

Technical Field

[0001] This invention belongs to the field of household paper technology, specifically relating to a method for improving the softness and strength properties of facial tissues. Background Technology

[0002] Facial tissues are an integral part of people's daily lives. In recent years, both the production and consumption of facial tissues have been increasing year by year, indicating that people's demand for household paper is constantly increasing. Moreover, with the improvement of living standards, people's requirements for its quality and user experience are also constantly improving.

[0003] Most everyday facial tissues use amino silicone oil as a softener, which has the disadvantages of low adhesion and the need for emulsification, resulting in high cost and complex formulas. Summary of the Invention

[0004] In view of this, the object of the present invention is to provide a method for improving the softness and strength properties of facial tissues. The method provided by the present invention is low in cost, simple in formulation and easy to operate, and the facial tissues prepared by the present invention have significantly improved softness and strength properties compared with facial tissues prepared by using amino silicone oil as a softener in the prior art.

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] This invention provides a method for improving the softness and strength properties of facial tissues, comprising the following steps:

[0007] Polyamide epichlorohydrin resin, diglyceride dioleate, glycerol-water solvent and wood pulp are mixed and then subjected to the first decomposition and papermaking in sequence to obtain the formed facial tissue base paper;

[0008] The amount of polyamide epichlorohydrin resin added is 3 to 12 kg / t of the oven-dry wood pulp; the amount of dioleoyl diglyceride added is 2 to 8 kg / t of the oven-dry wood pulp.

[0009] Preferably, the mass concentration of glycerol in the glycerol-water solvent is 70-80%; and the mass ratio of diglyceride diglyceride to glycerol-water solvent is 1:1.

[0010] Preferably, the wood pulp includes bleached softwood sulfate pulp and bleached hardwood pulp.

[0011] Preferably, after the papermaking process is completed, the process further includes drying and embossing the obtained facial tissue paper in sequence.

[0012] Preferably, the embossing pressure is 0.5 MPa.

[0013] Preferably, the preparation of the wood pulp includes the following steps:

[0014] Soak the wood pulp board in the first water, tear the resulting pulp board into small pieces, add the second water, and then perform the second desizing and pulping in sequence. Shake off the water, and then break it up again to obtain wood pulp.

[0015] Preferably, when the wood pulp comprises bleached softwood sulfate pulp and bleached hardwood pulp, and the wood pulp board comprises bleached softwood sulfate pulp board and bleached hardwood pulp board, the mass ratio of the bleached softwood sulfate pulp board to the bleached hardwood pulp board is (7-8):(2-3) based on oven-dry pulp.

[0016] Preferably, the second dissipation time is 4 to 6 minutes.

[0017] Preferably, the pulping to a pulping degree of 28–32°SR is achieved.

[0018] Preferably, the mass ratio of the wood pulp board to the volume of the first water is 360g:5L; the mass ratio of the wood pulp board to the volume of the second water is 360g:18L.

[0019] This invention provides a method for improving the softness and strength properties of facial tissue paper, comprising the following steps: mixing polyamide epichlorohydrin resin, diglyceride dioleate, glycerol-water solvent, and wood pulp, and sequentially performing a first defragmentation and papermaking process to obtain a shaped facial tissue paper base paper; wherein the amount of polyamide epichlorohydrin resin added is 6-12 kg / t of the oven-dry weight of the wood pulp; and the amount of diglyceride dioleate added is 2-8 kg / t of the oven-dry weight of the wood pulp.

[0020] Polyamide epichlorohydrin (PAE) resin is a water-soluble, cationic, thermosetting resin. It is formaldehyde-free, non-toxic, and odorless, and can be manufactured under neutral, slightly alkaline, and acidic conditions, with a wide pH range. PAE significantly improves both dry and wet strength, making it suitable for various paper production processes requiring high wet strength. Polyamide epichlorohydrin resin and diglyceride dioleate enhance the softness and physical strength of facial tissues. Diglyceride dioleate can be uniformly dispersed in a glycerol-water solvent without hindering the dispersion of PAE in the solution system. This allows both diglyceride dioleate and PAE to be uniformly dispersed in the glycerol-water solvent system without the need for emulsification, simplifying the facial tissue manufacturing process and reducing costs.

[0021] Furthermore, the present invention can significantly improve the softness of facial tissues through embossing. Detailed Implementation

[0022] This invention provides a method for improving the softness and strength properties of facial tissues, comprising the following steps:

[0023] Polyamide epichlorohydrin resin, diglyceride dioleate, glycerol-water solvent and wood pulp are mixed and then subjected to a first disintegration and papermaking process to obtain the formed facial tissue base paper.

[0024] Unless otherwise specified, all materials and equipment used in this invention are commercially available.

[0025] In this invention, the wood pulp preferably includes bleached softwood sulfate pulp and bleached hardwood pulp. In this invention, the preparation of the wood pulp preferably includes the following steps:

[0026] Soak the wood pulp board in the first water, tear the resulting pulp board into small pieces, add the second water, and then perform the second desizing and pulping in sequence. Shake off the water, and then break it up again to obtain wood pulp.

[0027] In this invention, when the wood pulp preferably includes bleached softwood sulfate pulp and bleached hardwood pulp, the wood pulp board preferably includes bleached softwood sulfate pulp board and bleached hardwood pulp board. Based on oven-dry pulp, the mass ratio of the bleached softwood sulfate pulp board to the bleached hardwood pulp board is preferably (7-8):(2-3), more preferably 8:2. In this invention, the mass ratio of the wood pulp board to the volume of the first water is preferably 360g:5L; the mass ratio of the wood pulp board to the volume of the second water is preferably 360g:18L. In this invention, the soaking time is preferably ≥4h; the temperature of the remaining water is preferably 20℃; the second dissolution time is preferably 4-6min, more preferably 5min.

[0028] In this invention, the pulping is preferably carried out after the second dissolution is completed without small lumps; the pulping is preferably carried out to a freeness of 28-32°SR, and more preferably 29-31°SR.

[0029] After the mixing process is completed, the present invention preferably places the resulting mixed slurry into a sealed bag, then places it in a refrigerator to evenly distribute the moisture, measures the moisture content, and refrigerates it for later use. By measuring the moisture content, the present invention can calculate the required mass of the mixed slurry based on the basis weight of facial tissues.

[0030] After obtaining the wood pulp, the present invention mixes polyamide epichlorohydrin resin, diglyceride dioleate, glycerol-water solvent and wood pulp, and performs first delamination and papermaking in sequence to obtain the formed facial tissue base paper.

[0031] In this invention, the mixing of polyamide epichlorohydrin resin, diglyceride dioleate, glycerol-water solvent and wood pulp preferably includes: first mixing diglyceride dioleate and glycerol-water solvent, then adding polyamide epichlorohydrin resin dropwise, and then second mixing the resulting PAE-diglyceride dioleate composite liquid and wood pulp.

[0032] In this invention, the mass concentration of glycerol in the glycerol-water solvent is preferably 70-80%, more preferably 72-78%; the mass ratio of diglyceride diglyceride to glycerol-water solvent is preferably 1:1.

[0033] In this invention, the amount of dioleoyl diglyceride added is 2-8 kg / t of the oven-dry weight of the wood pulp, preferably 2.5-6.5 kg / t, and more preferably 4-6 kg / t; the amount of polyamide epichlorohydrin resin added is 3-12 kg / t of the oven-dry weight of the wood pulp, preferably 5-11.5 kg / t, and more preferably 7-10.5 kg / t. In this invention, the basis weight of the facial tissue base paper is preferably 15 g / m³. 2 .

[0034] Polyamide epichlorohydrin (PAE) resin is a water-soluble, cationic, thermosetting resin. It is formaldehyde-free, non-toxic, and odorless, and can be manufactured under neutral, slightly alkaline, and acidic conditions, with a wide pH range. PAE significantly improves both dry and wet strength, making it suitable for various paper production processes requiring high wet strength. Polyamide epichlorohydrin resin and diglyceride dioleate enhance the softness and physical strength of facial tissues. Diglyceride dioleate can be uniformly dispersed in a glycerol-water solvent without hindering the dispersion of PAE in the solution system, ensuring uniform dispersion of both diglyceride dioleate and PAE in the glycerol-water solvent system.

[0035] After the papermaking process is completed, the present invention preferably further includes drying and embossing the obtained facial tissue paper in sequence.

[0036] In this invention, the embossing pressure is preferably 0.5 MPa. This invention, through embossing, can significantly improve the softness of facial tissues.

[0037] To further illustrate the present invention, the following detailed description of a method for improving the softness and strength properties of facial tissues provided by the present invention is provided in conjunction with embodiments, but these descriptions should not be construed as limiting the scope of protection of the present invention.

[0038] The pulp used in this embodiment of the invention was obtained from Zhejiang Jingxing Paper Industry Co., Ltd.; diglyceride dioleate was obtained from Shandong Binzhou Jinsheng New Material Technology Co., Ltd.; PAE was obtained from Vinda; deionized water was prepared in the laboratory; glycerol was purchased from Maclean's Reagents; and embossing equipment was provided by Vinda.

[0039] Example 1

[0040] One method for improving the softness and strength properties of facial tissues is as follows:

[0041] Weigh out 360g of bleached softwood sulfate pulp board and bleached hardwood pulp board (based on oven-dry pulp) at a mass ratio of 8:2. Soak the pulp boards in 5L of water for at least 4 hours. Then tear the pulp boards into small pieces of about 4cm×4cm for pulping. Add 18L of deionized water at 20°C to the pulp tank of the Wali pulper. After starting the pulper, slowly add the pulp into the pulper and control the dispersing time to about 5 minutes. After dispersing until there are no small pulp lumps, mix and pulp to 29°SR. After pulping, take out the pulp, shake off the water, disperse it with a dispersing instrument, put it into a sealed bag, put it in the refrigerator to even out the moisture, measure the moisture content, and then refrigerate for later use.

[0042] Diglyceride dioleate was placed in a 70% glycerol solution (the mass ratio of diglyceride dioleate to the 70% glycerol solution was 1:1), and PAE was added and stirred evenly to obtain a PAE-diglyceride dioleate composite solution; wherein, the amount of diglyceride dioleate was 2 kg / t, and the amount of PAE added was 3 kg / t, both relative to the oven-dry pulp weight.

[0043] The obtained PAE-dioleoyl diglyceride composite liquid and the refrigerated mixed pulp were placed under a desoldering machine for desoldering and mixing. The mixture was then transferred to a long-wire paper machine for pulp web forming. The base paper was dried and ready for use.

[0044] The dried facial tissues are embossed using an embossing machine with a pressure of 0.5 MPa. The left side of the control slider is aligned with the scale "3.0" (this slider on the embossing machine is used to control the embossing depth; the larger the value, the greater the embossing depth), thus obtaining the facial tissues.

[0045] Three parallel experiments were conducted using the method described above, with Vinda facial tissue paper as a blank control.

[0046] Example 2

[0047] Using the same raw materials and preparation method as in Example 1, the amount of diglyceride dioleate was changed to 4 kg / t, and the amount of PAE added was 6 kg / t.

[0048] Perform three parallel experiments using the method described above.

[0049] Example 3

[0050] Using the same raw materials and preparation method as in Example 1, the amount of diglyceride dioleate was changed to 8 kg / t, and the amount of PAE added was 9 kg / t.

[0051] Perform three parallel experiments using the method described above.

[0052] Example 4

[0053] Using the same raw materials and preparation method as in Example 1, the amount of diglyceride dioleate was changed to 8 kg / t, and the amount of PAE added was 12 kg / t.

[0054] Perform three parallel experiments using the method described above.

[0055] Example 5

[0056] Using the same raw materials and preparation method as in Example 1, the amount of diglyceride dioleate was changed to 8 kg / t, and the amount of PAE added was 6 kg / t.

[0057] Perform three parallel experiments using the method described above.

[0058] Comparative Example 1

[0059] Using the same raw materials and preparation method as in Example 1, the amount of diglyceride dioleate was changed to 0 kg / t, and the amount of PAE added was 0 kg / t; the embossing treatment was omitted. This is equivalent to the base paper.

[0060] Perform three parallel experiments using the method described above.

[0061] Comparative Example 2

[0062] Using the same raw materials and preparation method as in Example 1, the amount of diglyceride dioleate was changed to 0 kg / t, and the amount of PAE added was 3 kg / t; the embossing treatment was cancelled.

[0063] Perform three parallel experiments using the method described above.

[0064] Comparative Example 3

[0065] Using the same raw materials and preparation method as in Example 1, the amount of diglyceride dioleate was changed to 4 kg / t, and the amount of PAE added was 0 kg / t.

[0066] Perform three parallel experiments using the method described above.

[0067] Comparative Example 4

[0068] Using the same raw materials and preparation method as in Example 1, the embossing process was omitted.

[0069] Perform three parallel experiments using the method described above.

[0070] Comparative Example 5

[0071] Using the same raw materials and preparation method as in Example 1, the amount of diglyceride dioleate was changed to 0 kg / t, and the amount of PAE added was 3 kg / t.

[0072] Perform three parallel experiments using the method described above.

[0073] Comparative Example 6

[0074] Using the same raw materials and preparation method as in Example 1, the amount of diglyceride dioleate was changed to 4 kg / t, and the amount of PAE added was 3 kg / t.

[0075] Perform three parallel experiments using the method described above.

[0076] Performance testing

[0077] The facial tissues prepared in Examples 1-5 and Comparative Examples 1-6, which combine softness and strength, were placed at a temperature of (23±1)℃ and a humidity of (50±2)% for more than 4 hours for equilibration. Their tensile strength (GB / T12914-2018) and softness HF value (GB / T 8942-2016) were tested, and the test results are shown in Table 1.

[0078] Table 1. Tensile index and HF value of facial tissues prepared in Examples 1-5 and Comparative Examples 1-6

[0079]

[0080] As can be seen from Table 1, the facial tissues prepared using the improved method provided by the present invention have good softness and strength properties, and the preparation method provided by the present invention has low cost and is suitable for large-scale production.

[0081] Comparative Example 1 shows that the tensile strength and softness of the base paper are relatively poor compared to the treated facial tissue in Example 1.

[0082] Comparative Example 2 shows that, compared with Comparative Example 1, the tensile strength of the paper is significantly higher after adding PAE.

[0083] Comparative Example 3 shows that, compared with Comparative Example 1, the paper with added diglyceride dioleate has significantly better softness properties.

[0084] Comparative Example 4 shows that embossing improves both the softness and tensile strength of facial tissues.

[0085] Compared to Comparative Example 2, Comparative Example 5 further demonstrates that the strength properties of paper are improved after embossing treatment.

[0086] Compared to Comparative Example 5, Comparative Example 6 further demonstrates that the paper softening properties are improved after treatment with diglyceride dioleate.

[0087] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for improving the softness and strength properties of facial tissues, comprising the following steps: Diglyceride dioleate and glycerol-water solvent are first mixed, then polyamide epichlorohydrin resin is added dropwise, and the resulting PAE-diglyceride dioleate composite liquid is then mixed with wood pulp pulp. The first disintegration and papermaking are carried out in sequence to obtain the formed facial tissue base paper. The amount of polyamide epichlorohydrin resin added is 5-12 kg / t of the oven-dry weight of the wood pulp; the amount of diglyceride dioleate added is 4-8 kg / t of the oven-dry weight of the wood pulp. The glycerol-water solvent has a glycerol mass concentration of 70-80%; the mass ratio of dioleoyl diglyceride to the glycerol-water solvent is 1:

1. The obtained facial tissue paper base paper is dried and embossed in sequence; the embossing pressure is 0.5 MPa.

2. The preparation method according to claim 1, characterized in that, The wood pulp includes bleached softwood sulfate pulp and bleached hardwood pulp.

3. The method according to claim 1 or 2, characterized in that, The preparation of the wood pulp includes the following steps: Soak the wood pulp board in the first water, tear the resulting pulp board into small pieces, add the second water, and then perform the second desizing and pulping in sequence. Shake off the water, and then break it up again to obtain wood pulp.

4. The method according to claim 3, characterized in that, When the wood pulp includes bleached softwood sulfate pulp and bleached hardwood pulp, and the wood pulp board includes bleached softwood sulfate pulp board and bleached hardwood pulp board, the mass ratio of the bleached softwood sulfate pulp board to the bleached hardwood pulp board is (7~8):(2~3) based on oven-dry pulp.

5. The method according to claim 3, characterized in that, The second dredging time is 4-6 minutes.

6. The method according to claim 3, characterized in that, The pulping is performed to a freeness of 28~32°SR.

7. The method according to claim 3, characterized in that, The mass ratio of the wood pulp board to the volume of the first water is 360g:5L; the mass ratio of the wood pulp board to the volume of the second water is 360g:18L.

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