Preparation method and application of disposable molded pulp embedding box

Abstract

The invention relates to a preparation method and application of a disposable embedding box. The preparation method of the disposable molded pulp embedding box comprises the following steps: crushing and defibering a raw material pulp board, and pulping; carrying out compression molding treatment by adopting a wet compression molding process to obtain a wet blank body with at least one small-size embedding box wet blank; drying and shaping the wet green body, and treating until the water content is 8-14% to obtain a paper pulp molded green body; then cutting and punching the paper pulp molded blank body by adopting a cutting and punching die; and finally, carrying out surface treatment and thermocuring by adopting a curing agent to obtain the disposable molded pulp embedding box. The embedding box can ensure the stable structure and performance in the use period, can be degraded and recycled well after being discarded, is easy to process and low in production cost, and can be widely applied to the biological and medical fields.

Description

Technical Field

[0001] The present invention relates to the field of embedding cassettes, in particular to a preparation method and application of a disposable pulp molded embedding cassette. Background Art

[0002] Embedding is the process of using an embedding agent (which can be organic plastic, metal, etc.) to wrap the material powder or other block structure to be embedded to provide performance support or chemical protection. The embedding box is a material used to complete the material holding in the embedding experiment. However, the disposable embedding boxes currently on the market are made of plastic (such as PP, POM) or resin. For example, the embedding box disclosed in the Chinese patent with patent application number 200980134917.8, the box body and the film layer are made of polyester resin. The biggest problem with these embedding boxes is that they cannot be quickly degraded and recycled. But at the same time, the embedding box is required to withstand formaldehyde for 24 hours, 70-100% ethanol for 10 hours, xylene for 2 hours, and paraffin at 65°C for 2 hours during use. Because it is necessary to soak in ethanol, formaldehyde, xylene and paraffin for a long time to maintain a stable structure and unaffected function, the protection performance is insufficient for the conventional degradable material preparation embedding box process, and its organic solvent protection needs to be further strengthened. Summary of the invention

[0003] The purpose of the present invention is to provide a method for preparing and applying a disposable pulp molded embedding cassette which can ensure stable structure and performance during use, can be well degraded and recycled after being discarded, and has simple processing and low production cost in view of the above-mentioned problems and shortcomings.

[0004] The technical solution of the present invention is achieved in this way:

[0005] The method for preparing the disposable pulp molded embedding cassette of the present invention comprises the following steps:

[0006] (1) The raw pulp board is crushed and decomposed and then pulped;

[0007] (2) Wet molding process is used to obtain a small-sized embedding box wet blank;

[0008] (3) Dry and shape the wet blank of the embedding box to a moisture content of 8-14% to obtain a pulp molded embedding box pre-finished product;

[0009] (4) Use cutting and punching dies to cut and punch the dried and shaped pulp molded embedding box pre-finished product;

[0010] (5) The pulp molded embedding box, which has been cut and punched, is surface treated with a curing agent and then thermally cured to obtain a disposable pulp molded embedding box that can meet the requirements of resistance to organic solvents.

[0011] Preferably, the pulp after pulping in the above step (1) is added with an auxiliary agent and mixed evenly. The auxiliary agent includes but is not limited to one or more of the following: calcium carbonate (CaCO3) ≤ 10%, alkyl ketene dimer (AKD) ≤ 10%, nanocellulose ≤ 5%, polyacrylamide (PAM) 0.25%-0.5%, starch 1%-3.5%, polyamide epichlorohydrin (PPE) 0.5%-1.5%. The above proportions are all for the amount of absolute dry pulp. After adding the auxiliary agent, the fibers of the pulp can be more closely combined together, and the structure and performance stability of the product are better.

[0012] Preferably, the pulp board in the above step (1) includes but is not limited to one or a combination of bamboo pulp, wood pulp, straw pulp, bagasse pulp, and reed pulp. Further preferably, bamboo pulp is used as the main raw material. The pulping is performed until the freeness is 450-550 mL. If the freeness is lower than this range, it will increase the difficulty of water filtration, which is not conducive to demoulding and forming, and the energy consumption will increase; if it is higher than this range, the bonding between the pulps will deteriorate, the strength of the entire embedding box will decrease, and it will not meet the use requirements.

[0013] In the above step (2), when the wet molding process is used for molding, in order to further improve the production efficiency, the upper mold and the lower mold of the molding machine are integrally provided with a plurality of upper cover models and bottom box models of small-sized embedding boxes arranged in sequence, so that after the molding process, each wet blank obtained has a plurality of small-sized embedding box wet blanks. Then, through cutting and punching in step (4), it is possible to obtain a plurality of pulp molded embedding box pre-finished products by preparing a pulp molded blank. Further, when wet molding is performed, the slurry concentration is 2.5‰-3.5‰, the upper mold temperature is 140-150℃, the lower mold temperature is 150-160℃, the slurry absorption time is 7-15s, the dehydration time is 10-20s, the pressure holding time is 110-130s, and the pressure is 20-25t. The lower mold in the present invention adopts a mesh mold. Because the mesh mold needs to drain and exhaust, heat energy will be lost, so the temperature is increased to compensate.

[0014] The method of drying and shaping the wet embedding box blank includes, but is not limited to, one or more of hot air drying, far infrared drying, and microwave drying.

[0015] The curing agent includes one or more of acrylic acid, polyurethane and vinyl resin curing agents, such as one or more combinations of acrylic acid, polycarbonate modified polyurethane, urethane and modified epoxy vinyl resin.

[0016] The method of using a curing agent to perform surface treatment and thermal curing on the pulp molded embedding box pre-finished product in the above step (5) is as follows: the pre-finished embedding box is placed in the curing agent for about 20 minutes, then taken out and wiped clean, spread on a polytetrafluoroethylene plate and placed in an 80°C oven for thermal curing.

[0017] The disposable pulp molded embedding box in the present invention is a small-sized embedding box with a maximum size less than or equal to 90mm. The specific embedding box size is determined according to the shape, and is generally divided into square, round and rectangular. Among them, the common internal dimensions of the square are 25×25×5mm, 30×30×5mm, 45×45×5mm, 60×60×5mm, etc.; the common dimensions of the circle are inner diameters of 25mm, 30mm, 50mm, etc.; the common internal dimensions of the rectangle are 30×20×5mm, 60×40×5mm, 90×50×5mm, etc. The disposable pulp molded embedding box provided in this scheme has an external dimension of 43x28x7mm and an internal dimension of 30×20×5mm.

[0018] The disposable pulp molded embedding cassette of the present invention can be widely used in biological and medical fields.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] 1. The raw materials used in the preparation of the embedding box are biomass raw materials such as bamboo pulp, wood pulp, straw pulp, bagasse pulp, and reed pulp. The raw materials are easy to obtain and can be well degraded and recycled after use and disposal, so they are environmentally friendly.

[0021] 2. The embedding box is prepared by pulp molding, which is easy to process and can ensure stable structure and performance during use.

[0022] 3. The surface treatment of the embedding box can meet the requirements of the embedding box being resistant to organic solvents and has good protective performance.

[0023] 4. When the present invention adopts a wet molding process for molding, a plurality of small-sized embedding box wet blanks can be formed at one time on a wet blank. Therefore, it is possible to obtain a plurality of pulp molded embedding box pre-finished products by preparing a pulp molded blank through cutting and punching, and the production efficiency is high.

[0024] 5. The present invention is mainly used for preparing small-sized embedding boxes by pulp molding.

[0025] The present invention will be further described below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the process flow of the present invention.

[0027] Figure 2This is a picture of a sample after wet molding and drying according to an embodiment of the present invention.

[0028] Figure 3 for Figure 2 Sample pictures after cutting and punching.

[0029] Figure 4 These are pictures of blank samples and samples after surface treatment.

[0030] Figure 5 This is a picture of the embedding box sample after surface treatment and soaking in ethanol, formaldehyde and xylene.

[0031] Figure 6 This is a picture of the embedding box sample after completing the pre-immersion treatment and then immersing in 65℃ paraffin.

[0032] Figure 7 This is a schematic diagram of a product after wet molding and drying according to another embodiment of the present invention. DETAILED DESCRIPTION

[0033] The method for preparing the disposable pulp molded embedding cassette of the present invention comprises the following steps:

[0034] (1) The raw pulp board is crushed and decomposed and then pulped; the pulp board includes but is not limited to one or a combination of bamboo pulp, wood pulp, straw pulp, bagasse pulp, and reed pulp, and the pulping process is performed until the freeness is 450-550mL.

[0035] (2) A wet molding process is used for molding to obtain a wet blank having at least one small-sized embedding cassette;

[0036] (3) Drying and shaping the wet body to a moisture content of 8-14% to obtain a pulp molding body; the drying and shaping method includes but is not limited to hot air drying, far infrared drying, microwave drying, one or more of the drying treatments.

[0037] (4) Using cutting and punching dies to cut and punch the pulp molded blank to obtain a small-sized pulp molded embedding box;

[0038] (5) The pulp molded embedding box, which has been cut and punched, is surface treated with a curing agent and then thermally cured to obtain a disposable pulp molded embedding box that can meet the requirements of resistance to organic solvents.

[0039] In the above step (2), when the wet molding process is used for molding, in order to enable a plurality of embedding boxes to be molded in one molding process to improve production efficiency, the present invention adopts a method in which a plurality of upper cover models and bottom box models of small-sized embedding boxes arranged in sequence are integrally provided on the upper mold and the lower mold of the molding machine, so that after the molding process, each wet blank obtained has a plurality of small-sized embedding box wet blanks (such as Figure 2 There are 4 of them, Figure 7 There are 12 of them), and after cutting and punching in step (4), a plurality of pulp molded embedding boxes can be obtained by preparing a pulp molded blank. When wet molding is performed in the above step (2), the slurry concentration is 2.5‰-3.5‰, the upper mold temperature is 140-150℃, the lower mold temperature is 150-160℃, the slurry absorption time is 7-15s, the dehydration time is 10-20s, the pressure holding time is 110-130s, and the pressure is 20-25t.

[0040] The curing agent includes one or more of acrylic, polyurethane and vinyl resin curing agents.

[0041] The method of using a curing agent to perform surface treatment and thermal curing on the pulp molded embedding box pre-finished product in the above step (5) is as follows: the pre-finished embedding box is placed in the curing agent for about 20 minutes, then taken out and wiped clean, spread on a polytetrafluoroethylene plate and placed in an 80°C oven for thermal curing.

[0042] The present invention is further described in detail below in conjunction with specific embodiments:

[0043] Example 1: Preparation of small-sized pulp molded embedding cassette:

[0044] (1) Select bamboo pulp board, crush it and beat it until the freeness is 500mL.

[0045] (2) A wet molding process is performed using a molding machine, wherein the upper mold and the lower mold of the molding machine are integrally provided with four upper cover models and bottom box models of small-sized embedding boxes arranged in sequence, so as to obtain a wet blank body having four small-sized embedding boxes, such as Figure 2 As shown, from left to right are the front, side and back of the wet blank. The size of each small-sized pulp molding embedding box wet blank is 43x28x7mm. During processing, the slurry concentration is 3.0‰, the upper mold temperature is 140℃, the lower mold temperature is 150℃, the slurry absorption time is 10s, the dehydration time is 14s, the pressure holding time is 115s, and the pressure is 22t.

[0046] (3) Drying is carried out by hot air drying combined with far infrared drying until the moisture content is 10%.

[0047] (4) Cutting and punching the dried and shaped pulp molded embedding boxes with a cutting and punching mold to obtain four pulp molded embedding boxes. Figure 3 As shown, from left to right are the front and back of each sample.

[0048] One of the four pulp molded embedding boxes was not treated with curing agent as a blank sample. The other three were treated with acrylic, polyurethane and vinyl resin curing agents. After being placed in the curing agent for 20 minutes, it was taken out and wiped clean, laid flat on a polytetrafluoroethylene plate and placed in an 80°C oven for heat curing to obtain a disposable pulp molded embedding box. Figure 4 As shown, from left to right are blank sample, acrylic surface treated sample, polyurethane surface treated sample, and vinyl resin surface treated sample. The sample treated with curing agent was subjected to waterproof test, 200 ml of water was poured into the buffer, and monitored for 2 hours. There was no water leakage in the internal structure and the structure was not loose.

[0049] Example 2: Preparation of small-sized pulp molded embedding cassettes: Add an auxiliary agent to the pulp after beating in step (1) above and mix well, and then proceed to step (2). The rest is the same as above.

[0050] The protective performance test of the disposable pulp molded embedding cassette prepared by the present invention is carried out:

[0051] The four samples of Example 1 were treated with non-immersion and immersion treatments (formaldehyde for 24 hours, anhydrous ethanol for 10 hours, xylene for 2 hours, and paraffin at 65°C for 2 hours). The effects of the three different treatment processes are shown in Figure 2. Figure 5-Figure 6 shown. Figure 5 From left to right are samples of acrylic surface pretreatment, polyurethane surface pretreatment, and vinyl resin surface pretreatment. Figure 6 for Figure 5 The samples were immersed in formaldehyde for 24 hours, anhydrous ethanol for 10 hours, xylene for 2 hours, and 65℃ paraffin for 2 hours. It can be seen from the figure that the three disposable pulp molded embedding boxes with surface treatment can maintain integrity after being immersed in organic solvents, and will not degrade under the action of organic solvents. And it can also increase the mechanical properties of the embedding box to a certain extent.

[0052] Tables 1 and 2 below show the performance test data of four disposable pulp molded embedding cassette samples.

[0053] Table 1 Sample tensile strength

[0054]

[0055]

[0056] Table 2 Sample tensile strength

[0057]

[0058] From the performance test data in the above two tables, it can be seen that the tensile strength and anti-tensile strength of the blank sample without curing agent surface pretreatment before soaking in organic solvents are significantly lower than those of the other three samples with surface pretreatment. And the three samples with surface pretreatment still have strong tensile strength and anti-tensile strength after long-term soaking in organic solvents. Their tensile strength and anti-tensile strength can basically reach the strength of the blank sample, or even far exceed the performance strength of the blank sample, which can meet the use requirements of organic solvent resistance, so the protective performance is good. This is because acrylic, polyurethane and vinyl resins are thermosetting materials, which can form a protective layer on the surface of the sample after the sample is treated to enhance the strength of the sample.

[0059] Although the present invention is described with reference to specific embodiments, such description is not intended to limit the present invention. With reference to the description of the present invention, other changes of the disclosed embodiments are predictable to those skilled in the art, and such changes should fall within the scope defined by the claims.

Claims

1. A method for preparing a disposable pulp molding embedding cassette, comprising the following steps: (1) The raw pulp board is crushed and decomposed and then pulped; (2) A wet molding process is used for molding to obtain a wet blank having at least one small-sized embedding cassette; (3) Drying and shaping the wet body to a moisture content of 8-14% to obtain a pulp molding body; (4) Using cutting and punching dies to cut and punch the pulp molded blank to obtain a small-sized pulp molded embedding box; (5) The pulp molded embedding box, which has been cut and punched, is surface treated with a curing agent and then thermally cured to obtain a disposable pulp molded embedding box that can meet the requirements of resistance to organic solvents.

2. The method for preparing a disposable pulp molding embedding cassette according to claim 1, characterized in that: Add additives to the pulp after beating in the above step (1) and mix them evenly; the additives include but are not limited to one or more of the following: calcium carbonate ≤10%, alkyl ketene dimer ≤10%, nanocellulose ≤5%, polyacrylamide 0.25%-0.5%, starch 1%-3.5%, polyamide epichlorohydrin 0.5%-1.5%.

3. The method for preparing a disposable pulp molding embedding cassette according to claim 1, characterized in that: In the above step (2), when the wet molding process is used for molding, the upper mold and the lower mold are integrally provided with a plurality of upper cover models and bottom box models of small-sized embedding boxes arranged in sequence. After the molding process, each wet blank obtained has a plurality of small-sized embedding box wet blanks. After cutting and punching in step (4), it is possible to obtain a plurality of pulp molded embedding box preliminary products by preparing a pulp molded blank.

4. The method for preparing a disposable pulp molding embedding cassette according to claim 1, characterized in that: When wet molding is performed in the above step (2), the slurry concentration is 2.5‰-3.5‰, the upper mold temperature is 140-150°C, the lower mold temperature is 150-160°C, the slurry absorption time is 7-15s, the dehydration time is 10-20s, the holding time is 110-130s, and the pressure is 20-25t.

5. The method for preparing a disposable pulp molding embedding cassette according to claim 1, characterized in that: The pulp board in the above step (1) includes but is not limited to one or a combination of bamboo pulp, wood pulp, straw pulp, bagasse pulp, and reed pulp, and is beaten to a freeness of 450-550 mL.

6. The method for preparing a disposable pulp molding embedding cassette according to claim 1, characterized in that: The method of drying and shaping the wet green body includes, but is not limited to, one or more of hot air drying, far infrared drying, and microwave drying.

7. The method for preparing a disposable pulp molding embedding cassette according to claim 1, characterized in that: The curing agent includes one or more of acrylic, polyurethane and vinyl resin curing agents.

8. The method for preparing a disposable pulp molding embedding cassette according to claim 1, characterized in that: The method of using a curing agent to perform surface treatment and thermal curing on the pulp molded embedding box pre-finished product in the above step (5) is as follows: the pre-finished embedding box is placed in the curing agent for about 20 minutes, then taken out and wiped clean, spread on a polytetrafluoroethylene plate and placed in an 80°C oven for thermal curing.

9. The method for preparing a disposable pulp molding embedding cassette according to claim 1, characterized in that: The maximum dimension of disposable pulp molded embedding cassettes is less than or equal to 90 mm.

10. Use of a disposable pulp molding embedding cassette according to any one of claims 1 to 8, characterized in that: Used in biological and medical fields.

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