Packaging adhesive for cigarettes and preparation method thereof

Abstract

The invention relates to the technical field of cigarette adhesives, in particular to a cigarette packaging adhesive and a preparation method thereof. The packaging adhesive for cigarettes comprises the following components in parts by weight: 360-400 parts of vinyl acetate, 60-100 parts of polyvinyl alcohol, 1-5 parts of an initiator, 30-80 parts of rosin, 5-20 parts of an emulsifier, 460-500 parts of deionized water, 1-20 parts of acrylic acid and 1-3 parts of a defoaming agent. After the rosin is added, the breakage degree of a packaging adhesive material matrix is obviously increased, the bag explosion phenomenon is greatly reduced, and the problem that an existing cigarette packaging adhesive is low in adhesive strength is solved. The packaging adhesive is simple in component, easy to prepare, excellent in effect and suitable for popularization and application, and the production cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of cigarette adhesive, in particular to a cigarette packaging adhesive and a preparation method thereof. Background Art

[0002] Performance is a major focus of attention in all walks of life in today's society. With the continuous advancement of technology in the tobacco industry, how to further improve product performance has become one of the key exploration directions of researchers in the industry. Among them, the surface treatment process of cigarette packages is a key factor affecting the appearance quality and performance of cigarette packages. Its main purpose is to improve the smoothness, glossiness, friction resistance and weather resistance of the surface of the cigarette package to enhance the overall texture of the product and ensure the adhesion effect of the subsequent packaging glue. Water-based varnish Water-based varnish refers to a liquid that uses water as a carrier and is applied online by a printing machine or offline by a glazing machine to increase the gloss, water resistance and wear resistance of paper prints. It can form an elastic film layer with good adhesion, so it is used as an adhesive base material when compounding thin films. As a good surface treatment process, it has been applied to the field of paper box processing technology.

[0003] Common cigarette package surface treatment processes in the prior art include UV varnish, water-based varnish, transfer aluminum film, composite PET cigarette package film, etc. The surface-treated cigarette packages have better wear resistance, scratch resistance, moisture-proof and heat-insulating properties, and can better protect the cigarettes inside from the external environment. However, the above-mentioned problems exist:

[0004] 1) After UV printing varnish is quickly cured by ultraviolet rays, it will form a dense coating on the surface of white cardboard. This coating will hinder the packaging glue from fully wetting and penetrating the surface of the white cardboard after varnishing. The packaging glue needs to fully contact and penetrate the surface of the substrate to form a strong bond. Secondly, after UV printing varnish is cured on the surface of white cardboard, the surface tension of the white cardboard changes, which increases the requirements for the bonding strength and cohesion of the packaging glue.

[0005] 2) The glossiness of the water-based glazing oil coating is low. On the one hand, it is because the water molecules evaporate slowly, which makes the coating uneven during the evaporation process; on the other hand, the presence of emulsion resin particles in the water-based glazing oil affects the surface smoothness of the coating;

[0006] 3) The aluminum film has a lower surface energy after being transferred to the white cardboard. The contact angle is an important parameter to measure the wettability of liquid on the solid surface. A smaller contact angle means that the adhesive can better wet the transfer paper surface and form an ideal adhesive strength. The low surface energy of the transfer film cardboard surface cannot enable the adhesive to achieve rapid leveling. As a result, it takes a long time for the adhesive to flow smoothly to cover the entire surface during the gluing process, and the packaging glue is easy to accumulate on the surface or form an uneven coating during bonding;

[0007] 4) The molecular chains in the PET film are slightly rigid. After modification, there are more polar groups on the molecular chains that can interact with other composite substrates. The surface molecules of the composite PET film are arranged very closely due to the tensile force field, so the surface energy of the composite PET film is low. From the perspective of interface bonding theory, the composite PET film has low surface energy, poor wettability, and low surface adhesion, making it difficult to be well composited with other substrates. Summary of the invention

[0008] In order to solve the problem of low adhesive strength of existing cigarette packaging adhesive, the present invention provides a cigarette packaging adhesive and a preparation method thereof.

[0009] According to a first aspect of the present invention, the present invention discloses a cigarette packaging adhesive, which comprises, by weight:

[0010] 360-400 parts of vinyl acetate, 60-100 parts of polyvinyl alcohol, 1-5 parts of initiator, 30-80 parts of rosin, 5-20 parts of emulsifier, 460-500 parts of deionized water, 1-20 parts of acrylic acid and 1-3 parts of defoaming agent.

[0011] According to one embodiment of the present invention, 380 parts of vinyl acetate, 80 parts of polyvinyl alcohol, 3 parts of initiator, 50 parts of rosin, 10 parts of emulsifier, 480 parts of deionized water, 10 parts of acrylic acid and 1.5 parts of defoaming agent.

[0012] According to one embodiment of the present invention, the emulsifier comprises, by weight:

[0013] 5-10 parts of ionic emulsifier and 5-10 parts of non-ionic emulsifier.

[0014] According to one embodiment of the present invention, the ionic emulsifier includes sodium lauryl sulfate; the nonionic emulsifier includes dodecylphenol polyoxyethylene ether.

[0015] According to one embodiment of the present invention, the initiator includes ammonium persulfate.

[0016] According to one embodiment of the present invention, the defoaming agent is a silicone defoaming agent.

[0017] According to an embodiment of the present invention, the viscosity of the packaging adhesive is equal to or greater than 2010 mPa·s.

[0018] According to a second aspect of the present invention, the present invention discloses a method for preparing a cigarette packaging adhesive, comprising the following steps:

[0019] Dissolving polyvinyl alcohol in deionized water at a temperature of 80-90° C. to obtain a first solution;

[0020] At room temperature, dissolving rosin in vinyl acetate to obtain a second solution;

[0021] dissolving an initiator in the first solution to obtain a third solution;

[0022] At a temperature of 75-85° C., the second solution, acrylic acid and emulsifier are uniformly dripped into the third solution within a first period of time to obtain a first glue solution;

[0023] Raising the temperature from 75-85° C. to 90-95° C. and keeping the temperature for a second time to obtain a second glue solution;

[0024] The temperature of 90-95° C. is lowered to 35-40° C., and a defoaming agent is added into the second glue solution and mixed to obtain packaging glue.

[0025] According to one embodiment of the present invention, the uniform speed is 60-80 kg / h.

[0026] According to one embodiment of the present invention, the first time is 3-5 hours;

[0027] The second time is greater than or equal to 30 minutes.

[0028] In order to solve the problem of low adhesive strength of existing cigarette packaging adhesives, the present invention has the following advantages:

[0029] 1. After adding rosin, the present invention greatly reduces the phenomenon of bag explosion. Due to the introduction of rosin, the initial adhesion of the substrate is enhanced, and the viscosity of the packaging adhesive is significantly improved, so that the packaging adhesive exhibits good bonding ability.

[0030] 2. By dissolving rosin with vinyl acetate, the monomer mixed with the rosin solution is added dropwise into the system. The conversion rate of vinyl acetate can reach more than 95% at a temperature of 80°C-85°C. The remaining other monomers can be discharged by heating and vacuuming in the continuous emulsion polymerization method of the present invention, thereby obtaining an environmentally friendly packaging adhesive.

[0031] 3. The packaging adhesive of the present invention has simple components and is easy to prepare, thus reducing production costs, having excellent effects and being suitable for popularization and application. DETAILED DESCRIPTION

[0032] The present disclosure will now be discussed with reference to several exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present disclosure, rather than implying any limitation on the scope of the present disclosure.

[0033] According to the first aspect of the present invention, this embodiment discloses a cigarette packaging adhesive, which comprises, by weight:

[0034] 360-400 parts of vinyl acetate, 60-100 parts of polyvinyl alcohol, 1-5 parts of initiator, 30-80 parts of rosin, 5-20 parts of emulsifier, 460-500 parts of deionized water, 1-20 parts of acrylic acid and 1-3 parts of defoaming agent.

[0035] In this embodiment, acrylic acid is a mixed monomer of acrylic acid, and deionized water is 460-500 parts, which can promote further reaction of some unreacted monomers and initiators in the components, making the reaction more complete.

[0036] According to one embodiment of the present invention, 380 parts of vinyl acetate, 80 parts of polyvinyl alcohol, 3 parts of initiator, 50 parts of rosin, 10 parts of emulsifier, 480 parts of deionized water, 10 parts of acrylic acid and 1.5 parts of defoaming agent.

[0037] According to one embodiment of the present invention, the emulsifier comprises, by weight:

[0038] 5-10 parts of ionic emulsifier and 5-10 parts of non-ionic emulsifier.

[0039] Preferably, the weight ratio of the ionic emulsifier to the nonionic emulsifier is 2:1-1:2, more preferably the weight ratio of the ionic emulsifier to the nonionic emulsifier is 1:1.

[0040] According to one embodiment of the present invention, the ionic emulsifier includes sodium lauryl sulfate; the nonionic emulsifier includes dodecylphenol polyoxyethylene ether.

[0041] According to one embodiment of the present invention, the initiator includes ammonium persulfate.

[0042] According to one embodiment of the present invention, the defoaming agent is a silicone defoaming agent.

[0043] According to an embodiment of the present invention, the viscosity of the packaging adhesive is equal to or greater than 2010 mPa·s.

[0044] According to the first invention of the present invention, this embodiment discloses a method for preparing a cigarette packaging adhesive, comprising the following steps:

[0045] Dissolving polyvinyl alcohol in deionized water at a temperature of 80-90° C. to obtain a first solution;

[0046] At room temperature, dissolving rosin in vinyl acetate to obtain a second solution;

[0047] dissolving an initiator in the first solution to obtain a third solution;

[0048] At a temperature of 75-85° C., the second solution, acrylic acid and emulsifier are uniformly dripped into the third solution within a first period of time to obtain a first glue solution;

[0049] Raising the temperature from 75-85° C. to 90-95° C. and keeping the temperature for a second time to obtain a second glue solution;

[0050] The temperature of 90-95° C. is lowered to 35-40° C., and a defoaming agent is added into the second glue solution and mixed to obtain packaging glue.

[0051] In this embodiment, polyvinyl alcohol is dissolved in deionized water, which can help stabilize the latex group in the subsequent emulsion polymerization process, prevent the generation of emulsion stratification or precipitation, and protect the colloid. Rosin is added to vinyl acetate to increase the viscosity of the packaging glue, thereby improving the bonding strength, thereby improving the bonding effect of the packaging glue. The initiator is added to the dissolved polyvinyl alcohol aqueous solution to improve the stability of the polyvinyl alcohol aqueous solution. The second solution, acrylic acid and emulsifier are uniformly dripped into the third solution within the first time to ensure that the polymer reacts smoothly during the process, and the control of temperature, dripping speed and time during the reaction process allows the vinyl acetate mixed with rosin and acrylic acid to react more fully. The temperature is raised from 75-85°C to 90-95°C, and the temperature is kept for the second time to prevent the temperature of the emulsion system from fluctuating too much, thereby maintaining the stability of the emulsion, avoiding the generation of gel or precipitation, and thus ensuring the quality of the final product. In addition, the emulsion polymerization reaction can be completed in this process to improve the conversion rate. Lowering the temperature from 90-95°C to 35-40°C can ensure that the reaction is carried out at a stable temperature and avoid abnormal reactions caused by temperature fluctuations. Since the activity of the defoaming agent will be affected at high temperatures, adding the defoaming agent at this time can better play the role of the defoaming agent and effectively decompose and eliminate bubbles.

[0052] According to one embodiment of the present invention, the uniform speed is 60-80 kg / h.

[0053] According to one embodiment of the present invention, the first time is 3-5 hours; the second time is greater than or equal to 30 minutes.

[0054] Example 1

[0055] This embodiment provides a formula for preparing cigarette packaging adhesive, which includes, by weight:

[0056] 380kg of vinyl acetate, 80kg of polyvinyl alcohol, 3kg of ammonium persulfate, 50kg of rosin, 10kg of emulsifier, 480kg of deionized water, 10kg of acrylic acid and 1.5kg of silicone defoamer.

[0057] This embodiment provides a method for preparing a cigarette packaging adhesive, which is carried out by a continuous emulsion polymerization method. The preparation method comprises the following steps:

[0058] After heating the deionized water to 90° C., stop heating and keep the temperature of the deionized water at 90° C., add polyvinyl alcohol into the deionized water at 90° C., and after the polyvinyl alcohol is completely dissolved, obtain a first solution for standby use;

[0059] Add rosin to vinyl acetate and dissolve at room temperature, and after the rosin is completely dissolved, obtain a second solution for standby use;

[0060] Adding ammonium persulfate slowly and uniformly into the first solution of dissolved polyvinyl alcohol, and after sodium persulfate is completely dissolved, obtaining a third solution;

[0061] The temperature of the third solution is lowered to 82° C. and then the temperature is stopped. The second solution, acrylic acid and emulsifier are dripped into the third solution while the temperature of the third solution is maintained at 82° C. The second solution, acrylic acid and emulsifier are dripped at an average speed of 80 kg / h within 5 hours to obtain a first adhesive solution;

[0062] The temperature of the first glue solution is raised to 90°C-95°C, and then the temperature is stopped and kept warm for 30 minutes to obtain a second glue solution;

[0063] When the temperature of the second adhesive solution is reduced to 40° C., the organosilicon defoamer is added to the second adhesive solution, and the packaging adhesive is obtained after the defoamer and the first adhesive solution are evenly mixed. The packaging adhesive is then packaged to complete the production of the packaging adhesive.

[0064] Preferably, the emulsifier is a composite emulsifier obtained by mixing 5 parts of sodium lauryl sulfate which is an ionic emulsifier and 5 parts of dodecylphenol polyoxyethylene ether which is a non-ionic emulsifier.

[0065] Example 2

[0066] This embodiment provides a formula for preparing cigarette packaging adhesive, which includes, by weight:

[0067] 360kg of vinyl acetate, 60kg of polyvinyl alcohol, 1kg of ammonium persulfate, 30kg of rosin, 5kg of emulsifier, 460kg of deionized water, 5kg of acrylic acid and 1kg of silicone defoamer.

[0068] This embodiment provides a method for preparing a cigarette packaging adhesive, which is carried out by a continuous emulsion polymerization method. The preparation method comprises the following steps:

[0069] After heating the deionized water to 80° C., stop heating and keep the temperature of the deionized water at 80° C., add polyvinyl alcohol into the deionized water at 80° C., and after the polyvinyl alcohol is completely dissolved, obtain a first solution for standby use;

[0070] Add rosin to vinyl acetate and dissolve at room temperature, and after the rosin is completely dissolved, obtain a second solution for standby use;

[0071] Adding ammonium persulfate slowly and uniformly into the first solution of dissolved polyvinyl alcohol, and after sodium persulfate is completely dissolved, obtaining a third solution;

[0072] The temperature of the third solution is lowered to 75° C. and then the temperature is stopped. The second solution, acrylic acid and emulsifier are dripped into the third solution while the temperature of the third solution is kept at 75° C. The second solution, acrylic acid and emulsifier are dripped at a uniform speed of 80 kg / h within 5 hours to obtain a first adhesive solution.

[0073] The temperature of the first glue solution is raised to 90°C-95°C, and then the temperature is stopped and kept warm for 30 minutes to obtain a second glue solution;

[0074] When the temperature of the second adhesive solution is reduced to 30° C., the organosilicon defoamer is added to the second adhesive solution, and the packaging adhesive is obtained after the defoamer and the first adhesive solution are evenly mixed. The packaging adhesive is then packaged to complete the production of the packaging adhesive.

[0075] Preferably, the emulsifier is a composite emulsifier obtained by mixing 5 parts of sodium lauryl sulfate which is an ionic emulsifier and 5 parts of dodecylphenol polyoxyethylene ether which is a non-ionic emulsifier.

[0076] Example 3

[0077] This embodiment provides a formula for preparing cigarette packaging adhesive, which includes, by weight:

[0078] 400kg of vinyl acetate, 100kg of polyvinyl alcohol, 5kg of ammonium persulfate, 80kg of rosin, 20kg of emulsifier, 500kg of deionized water, 20kg of acrylic acid and 3kg of silicone defoamer.

[0079] This embodiment provides a method for preparing a cigarette packaging adhesive, which is carried out by a continuous emulsion polymerization method. The preparation method comprises the following steps:

[0080] After heating the deionized water to 85° C., stop heating and keep the temperature of the deionized water at 85° C., add polyvinyl alcohol into the deionized water at 85° C., and after the polyvinyl alcohol is completely dissolved, obtain a first solution for standby use;

[0081] Add rosin to vinyl acetate and dissolve at room temperature, and after the rosin is completely dissolved, obtain a second solution for standby use;

[0082] Adding ammonium persulfate slowly and uniformly into the first solution of dissolved polyvinyl alcohol, and after sodium persulfate is completely dissolved, obtaining a third solution;

[0083] The temperature of the third solution is lowered to 75°C and then the temperature is stopped. The second solution, acrylic acid and emulsifier are dripped into the third solution while the temperature of the third solution is kept at 75°C. The second solution, acrylic acid and emulsifier are dripped at an average speed of 80 kg / h within 3 hours to obtain a first adhesive solution.

[0084] The temperature of the first glue solution was raised to 95° C., then the temperature was stopped and kept warm for 30 minutes to obtain a second glue solution;

[0085] When the temperature of the second adhesive solution is reduced to 40° C., the organosilicon defoamer is added to the second adhesive solution, and the packaging adhesive is obtained after the defoamer and the first adhesive solution are evenly mixed. The packaging adhesive is then packaged to complete the production of the packaging adhesive.

[0086] Preferably, the emulsifier is a composite emulsifier obtained by mixing 5 parts of sodium lauryl sulfate which is an ionic emulsifier and 5 parts of dodecylphenol polyoxyethylene ether which is a non-ionic emulsifier.

[0087] Comparative Example 1

[0088] This embodiment differs from the embodiment in that rosin is not used.

[0089] The curing time test was performed on the packaging adhesive obtained in Example 1 and Comparative Example 1. The test steps are as follows:

[0090] (1) Use a disposable pipette to draw up the glue solution and place it in the aluminum foil dish inside the balance;

[0091] (2) Drop the glue on a corner of the cigarette box paper (the weight of the emulsion is controlled at 0.03-0.05g);

[0092] Press the emulsion onto the substrate with finger pressure, and peel the substrate continuously and steadily from left to right every 4 seconds until the fiber breaks obviously, and record the number of times at 4-second intervals;

[0093] (3) Read the weight of the emulsion on the electronic balance and record it. Repeat the above steps 6 times.

[0094] The curing time test data of the packaging adhesive of Example 1 on the white cardboard treated with UV varnish is shown in Table 1, and the curing time test data of the packaging adhesive of Comparative Example 1 on the white cardboard treated with UV varnish is shown in Table 2.

[0095] Table 1 Curing time test of packaging adhesive of Example 1 on white cardboard treated with UV varnish

[0096]

[0097]

[0098] Table 2 Curing time test of packaging adhesive of comparative example 1 on white cardboard treated with UV varnish

[0099] Glue weight / g Time interval / s Fiber rupture degree 0.0387 4 Fried buns 0.0398 8 Fried buns 0.0481 12 Slight material damage 0.0348 16 Slight material damage 0.0376 20 Obviously broken 0.0394 24 Obviously broken

[0100] From Table 1 and Table 2, it can be seen that when the weight of the packaging glue of Example 1 is 0.0394g, the fiber is slightly broken in a total of 24 seconds from bonding to peeling, while when the weight of the packaging glue of Comparative Example 1 is 0.0394g, obvious fiber breakage occurs at the 24th second. When the weight of the packaging glue of Example 1 is 0.0387g, the fiber is slightly broken in a total of 4 seconds from bonding to peeling. When the weight of the packaging glue of Comparative Example 1 is 0.0387g, the package explodes at the 4th second. According to the test, the cracking degree of the material matrix is ​​significantly reduced after adding rosin compared with that before adding rosin, and the phenomenon of bursting the package is greatly reduced. Due to the introduction of rosin, the initial adhesion of the substrate is significantly enhanced, and the viscosity of the packaging adhesive is significantly improved, so that the packaging adhesive exhibits good bonding ability, so that when the packaging adhesive of the present invention is used on cigarettes in actual work, the bonding effect of the cigarettes is increased, and the cigarette materials are not easy to tear apart, and the cracking degree of the cigarette materials increases.

[0101] The viscosity and solid content of the packaging adhesive obtained in Example 1 and Comparative Example 1 were tested according to the national "Tobacco Industry Standard" YC / T 188-2004. The test data are shown in Table 3.

[0102] Table 3: Viscosity and solid content of packaging adhesive obtained in Example 1 and Comparative Example 1

[0103]

[0104] In the whole system of the packaging adhesive of the present invention, vinyl acetate is a hard monomer. After adding rosin, the initial adhesion can be significantly improved, which solves the problem that the initial adhesion is insufficient when bonding cigarette boxes due to vinyl acetate being a hard monomer, and the cigarette boxes will have flash when the speed is too fast. By dissolving the rosin with vinyl acetate and dripping the monomer mixed with the rosin solution into the system, the conversion rate of vinyl acetate can reach more than 95% at a temperature of 80°C-85°C, and the remaining other monomers can be discharged by heating and vacuuming in the continuous emulsion polymerization method of the present invention, so as to obtain environmentally friendly packaging adhesive.

[0105] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present disclosure, and in actual applications, various changes may be made thereto in form and detail without departing from the scope of the present disclosure.

Claims

1. A cigarette packaging adhesive, characterized in that: In parts by weight: 360-400 parts of vinyl acetate, 60-100 parts of polyvinyl alcohol, 1-5 parts of initiator, 30-80 parts of rosin, 5-20 parts of emulsifier, 460-500 parts of deionized water, 1-20 parts of acrylic acid and 1-3 parts of defoaming agent.

2. The cigarette packaging adhesive according to claim 1, characterized in that: In parts by weight: 380 parts of vinyl acetate, 80 parts of polyvinyl alcohol, 3 parts of initiator, 50 parts of rosin, 10 parts of emulsifier, 480 parts of deionized water, 10 parts of acrylic acid and 1.5 parts of defoamer.

3. The cigarette packaging adhesive according to claim 1, characterized in that: The emulsifier comprises, by weight: 5-10 parts of ionic emulsifier and 5-10 parts of non-ionic emulsifier.

4. The cigarette packaging adhesive according to claim 3, characterized in that: The ionic emulsifier includes sodium lauryl sulfate; the nonionic emulsifier includes dodecylphenol polyoxyethylene ether.

5. The cigarette packaging adhesive according to claim 1, characterized in that: The initiator includes ammonium persulfate.

6. The cigarette packaging adhesive according to claim 1, characterized in that: The defoamer is an organosilicon defoamer.

7. The cigarette packaging adhesive according to claim 1, characterized in that: The viscosity of the packaging glue is equal to or greater than 2010 mPa·s.

8. A method for preparing a cigarette packaging adhesive as claimed in any one of claims 1 to 7, characterized in that: The steps include: Dissolving polyvinyl alcohol in deionized water at a temperature of 80-90° C. to obtain a first solution; At room temperature, dissolving rosin in vinyl acetate to obtain a second solution; dissolving an initiator in the first solution to obtain a third solution; At a temperature of 75-85° C., the second solution, acrylic acid and emulsifier are uniformly dripped into the third solution within a first period of time to obtain a first glue solution; Raising the temperature from 75-85° C. to 90-95° C. and keeping the temperature for a second time to obtain a second glue solution; The temperature of 90-95° C. is lowered to 35-40° C., and a defoaming agent is added into the second glue solution and mixed to obtain packaging glue.

9. The method for preparing a cigarette packaging adhesive according to claim 8, characterized in that: The uniform speed is 60-80 kg / h.

10. The method for preparing a cigarette packaging adhesive according to claim 8, characterized in that: The first time is 3-5 hours; the second time is greater than or equal to 30 minutes.

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