阅读说明：本技术 一种新型笔芯封蜡及其制备方法 (Novel pen refill sealing wax and preparation method thereof ) 是由 吴红建 王通虎 于 2021-01-07 设计创作，主要内容包括：本发明涉及一种新型笔芯封蜡的生产及应用,以改性乙烯-醋酸乙烯共聚物为主,增粘树脂、色粉、抗氧剂、分散剂为辅,通过加热釜共混制作而成。根据各组分比例不同,可制造多种不同熔点、粘度及色彩的封蜡,用于密封笔芯。(The invention relates to production and application of a novel pen core sealing wax, which is prepared by mixing modified ethylene-vinyl acetate copolymer serving as a main material with tackifying resin, toner, an antioxidant and a dispersing agent serving as auxiliary materials through a heating kettle. According to different proportions of the components, the wax sealer can be used for manufacturing a plurality of wax sealers with different melting points, viscosities and colors and used for sealing the pen core.)

1. A novel pen core sealing wax comprises modified ethylene-vinyl acetate copolymer.

2. The pen core sealing wax as claimed in claim 1, further comprising a tackifying resin, a dispersant, an antioxidant and a toner.

3. The pen core sealing wax as claimed in claim 2, which comprises the following components in parts by weight:

85-95 parts of modified ethylene-vinyl acetate copolymer;

5-15 parts of tackifying resin;

1-2 parts of a dispersing agent;

0.1-0.3 part of antioxidant;

0.1-1 part of toner.

4. The pen core sealing wax as claimed in claim 3, wherein the modified ethylene-vinyl acetate copolymer is a polyester blended modified ethylene-vinyl acetate copolymer with a number average molecular weight of 1500-1800 and a softening point temperature of 85-95 ℃.

5. The pen core sealing wax according to claim 3, wherein the tackifying resin is one of petroleum resin and epoxy resin.

6. The pen core sealing wax of claim 3, wherein the dispersing agent is at least one of polyethylene wax and vinyl bis stearamide.

7. The pen core sealing wax as claimed in any one of claims 1 to 6, wherein the softening point of the pen core sealing wax is 85-95 ℃, the processing temperature range is 110-150 ℃, and the processing viscosity is 1100-5000 Pa-s.

8. A preparation method of novel pen core sealing wax comprises the following steps:

step (a): adding the modified ethylene-vinyl acetate copolymer into a reaction kettle, heating and stirring until the modified ethylene-vinyl acetate copolymer is completely molten;

step (b): adding tackifying resin and antioxidant, and continuously stirring to obtain a mixture;

step (c): adding the toner and the dispersant, and continuously stirring for reaction;

step (d): discharging the materials to obtain the product.

9. The method according to claim 8,

the heating temperature in the step (a) is 135-145 ℃, and the stirring speed is between 500-1000 r/min;

the stirring speed in the step (b) is between 500 and 1000r/min, and the stirring time is 20-25 min;

the stirring speed of the step (c) is between 500 and 1000r/min, and the reaction time is 10-15 min.

Technical Field

The invention relates to the technical field of hot melting wax, in particular to a composition of refill sealing wax and a preparation method thereof.

Background

The materials used in the prior art for hot melt wax include paraffin, polyester, polyamide, etc. Paraffins are mainly used for lubrication systems. Polyester hot melt wax mainly adopts polyester resin, has high heat resistance, good weather resistance, water resistance and elasticity, and has the defects of high viscosity during heating and melting, difficult operation and general construction by using special machinery. The main body of the polyamide hot melting wax is polyamide resin, is tasteless and colorless, has excellent heat resistance, cold resistance, electrical property, oil resistance, chemical resistance and medium resistance, can be used for bonding various metals and nonmetals, and has the defects of higher viscosity and strong viscosity during heating and melting.

Disclosure of Invention

The processing temperature of the wax sealing of the thermal erasable pen core in the prior art is above 165 ℃, the decoloring temperature of the thermal erasable ink is usually 60 ℃, and after the wax is dotted on the pen core, the pen core is initially written with a certain decoloring length.

The initial writing and color erasing problems of the thermal erasable pen core are mainly caused by that the processing temperature of the wax sealing is too high, so that the thermal erasable ink is decolored. Through the test of reducing the processing temperature, when the processing temperature of the sealing wax is reduced to 130 ℃, the decoloring length can be reduced to be within 10 mm. However, in the conventional system, the viscosity of the sealing wax is increased when the processing temperature is lowered, and the phenomenon of uneven point wax is caused.

In order to solve the problem of the uneven contradiction between the high processing temperature decoloring and the low processing temperature wax point, the invention develops a novel pen core sealing wax, which has the following advantages:

firstly, the method is safe and environment-friendly. The novel pen core sealing wax is made of environment-friendly materials, does not have factors harmful to human bodies and the environment, and is superior to the prior similar materials in the aspects of safety and environment protection.

(II) low melting point and low viscosity. The novel pen core sealing wax adopts modified ethylene-vinyl acetate copolymer as a main material, tackifying resin, toner, antioxidant and dispersant as auxiliary materials, the melting temperature of the wax is reduced to 80-95 ℃, the processing temperature is reduced to 130-3000 cps, and the processing viscosity is 2000-3000 cps.

And (III) excellent adhesive property. The modified ethylene-vinyl acetate copolymer has excellent adhesiveness and can be adhered to the surface of a material. The kind of the adhesive material is increased by the tackifying resin.

The novel pen core wax sealing scheme is as follows:

it comprises modified ethylene-vinyl acetate copolymer.

Further, it includes a tackifying resin, a dispersant, an antioxidant 168 or 1010 and a toner (red pigment).

Further, the pen core wax sealing comprises the following components in parts by weight: 85-95 parts by weight of the modified ethylene-vinyl acetate copolymer, preferably 88-92 parts by weight; 5-15 parts of tackifying resin, preferably 8-12 parts; 1-2 parts of a dispersing agent; 0.1-0.3 part of antioxidant; the toner is 0.1 to 1 part, preferably 0.3 to 0.5 part.

Further, the modified ethylene-vinyl acetate copolymer is a polyester blending modified ethylene-vinyl acetate copolymer (purchased from outsourcing RT-2017N), the number average molecular weight is 1500-1800, and the softening point temperature is 85-95 ℃. The polyester blending modified ethylene-vinyl acetate copolymer comprises 15 parts of polyester resin, 85 parts of ethylene-vinyl acetate blend and 1 part of antioxidant, and is prepared by blending in a reaction kettle. Wherein the polyester resin is dimethyl terephthalate, polytetramethylene glycol ether and l, 4 butanediol, and the polyether type polyester copolymer is prepared through ester exchange reaction. The ethylene-vinyl acetate copolymer had a vinyl acetate content of 28% and an MI of 150. The polyester blending modified ethylene-vinyl acetate copolymer has excellent processability and low temperature resistance of the ethylene-vinyl acetate copolymer, and has better bonding strength, heat resistance and dry and wet cleaning resistance of the polyester copolymer.

Further, the tackifying resin is one of petroleum resin (C5, C9) and epoxy resin (E-20; E-30).

Further, the dispersing agent is at least one of polyethylene wax (CH-100B) and vinyl bis stearamide (EB-FF).

Further, the softening point of the pen core sealing wax is 85-95 ℃, the processing temperature range is 110-150 ℃, and the processing viscosity is 1100-5000Pa & s.

Most of the conventional pen core sealing wax adopts modified polyester or modified polyamide hot melt adhesive, the softening point temperature of the hot melt adhesive is about 110-150 ℃, and the processing temperature is 150-200 ℃. The system has lower processing temperature, and the decoloration length of the final finished product of the thermal erasable pen core can be obviously shortened.

In another aspect, the invention provides a preparation method of the novel pen core sealing wax, which comprises the following steps:

step (a): adding the modified ethylene-vinyl acetate copolymer into a reaction kettle, heating and stirring until the modified ethylene-vinyl acetate copolymer is completely molten;

step (b): adding tackifying resin and antioxidant, and continuously stirring to obtain a mixture;

step (c): adding the toner and the dispersant, and continuously stirring for reaction;

step (d): discharging the materials to obtain the product.

Further, the air conditioner is provided with a fan,

the heating temperature in the step (a) is 135-145 ℃, and the stirring speed is between 500-1000 r/min;

the stirring speed in the step (b) is between 500 and 1000r/min, and the stirring time is 20-25 min;

the stirring speed of the step (c) is between 500 and 1000r/min, and the reaction time is 10-15 min.

Meanwhile, the invention can be applied to different production equipment according to the use requirement, such as a heating reaction kettle, a wax dropping machine, coating equipment, hot melt extrusion equipment and the like.

The processing temperature of the wax sealing can be reduced to 130 ℃, the decoloring length of the thermal erasable pen core packaged by the wax sealing can be reduced to be within 10mm, and the quality and the use experience of products are improved. The adhesive has the advantages of low melting point, low viscosity, excellent bonding performance and the like, is safe and environment-friendly, can be produced according to actual use requirements, and is more widely applied to various products.

Drawings

FIG. 1 is a graph of temperature versus viscosity for a prior art wax seal process.

FIG. 2 is a graph of processing temperature versus viscosity for examples 1-3 of the present invention and comparative examples 1, 2.

Fig. 3 is an effect diagram of the invention after wax sealing and packaging the pen core. Wherein, 1-pen point and 2-wax sealing.

Detailed Description

The technical solution of the present invention is further explained below according to specific embodiments. The scope of protection of the invention is not limited to the following examples, which are set forth for illustrative purposes only and are not intended to limit the invention in any way.

The invention discloses a novel pen core sealing wax which comprises, by weight, 85-95 parts of modified ethylene-vinyl acetate copolymer, 5-15 parts of tackifying resin, 1-2 parts of dispersing agent, 0.1-0.3 part of antioxidant and 0.1-1 part of toner.

Wherein the modified ethylene-vinyl acetate copolymer is a polyester blending modified ethylene-vinyl acetate copolymer with the number average molecular weight of 1500-1800 and the softening point temperature of 85-95 ℃.

The tackifying resin is one of petroleum resin and epoxy resin.

The dispersing agent is at least one of polyethylene wax and vinyl bis stearamide.

When the pen core wax sealing agent is prepared, firstly, the modified ethylene-vinyl acetate copolymer is added into a reaction kettle, heated to 135-DEG C145 ℃, and stirred at the speed of 500-DEG C1000 r/min until the modified ethylene-vinyl acetate copolymer is completely melted; adding tackifying resin and antioxidant, and stirring for 20-25 min; and then adding the toner and the dispersing agent, continuously stirring, reacting for 10-15min, and discharging the materials to obtain the product.

The processing temperature of the refill sealing wax (the main body is polyamide hot melt adhesive 8022) in the prior art is above 165 ℃, and after the refill is dotted with wax, the refill can have a long erasing length at the beginning of writing. By the test of reducing the processing temperature, when the processing temperature of the sealing wax is reduced to 130 ℃, the decoloration length can be reduced to an acceptable degree within 10mm, but the viscosity of the sealing wax is increased at the moment, and the phenomenon of uneven wax spotting is generated.

FIG. 1 shows the processing temperature and viscosity data for a prior art sealing wax as measured by a hot melt viscometer, with a processing viscosity of about 1900pcs at 170 ℃. Referring to this data, a wax having a processing temperature of 130 ℃ and a processing viscosity of about 1900pcs meets both production and quality requirements. Embodiments of the present invention also ultimately address this need.

The present invention will be described in further detail with reference to examples.

TABLE 1 wax sealing Material composition for thermal erasable pen core (by weight)

The components of examples 1-3, comparative example 1 and comparative example 2 were weighed and placed separately for use according to the above formulation. The modified ethylene-vinyl acetate copolymer (RT-2017N) in example 1 is added into a reaction kettle, the heating temperature is set to 140 ℃, the mixture is stirred at the speed of 800r/min until the mixture is completely melted, and then tackifying resin (C5) and antioxidant (168) are added, and the stirring is continued for 20 min; and then adding a dispersing agent (EB-FF) and a toner (pigment red), continuously stirring and reacting for 15min, and discharging the materials to obtain the product. Example 2 and example 3 the process is referred to example 1. The heating temperature of comparative example 1 was set at 135 deg.C, the stirring time was 15min and 15min, respectively, and the order of addition was the same as in example 1. The heating temperature of comparative example 2 was set at 145 ℃ and the stirring time was 25min and 15min, respectively, in the same order as in example 1.

The above products were tested for processing temperature and viscosity data, respectively, as shown in FIG. 2, with example 1 having a processing viscosity of 1700pcs at 130 ℃; example 2 the processing viscosity was 1910pcs at 130 ℃; example 3 the processing viscosity was 2050pcs at 130 ℃; all three formulas meet the formula design goal.

When the actual pen core is packaged, sealing wax is added to the heating wax tank to 2/3, the processing temperature is set to be 135 ℃ (deviation of +/-5 ℃ is generated between the temperature of the wax tank and the actual temperature), after the sealing wax is melted, the pen core sequentially passes through a wax tank wax dispensing opening, the sealing wax can be bonded on the surface of the pen head, the pen core sealing wax process is completed, and the actual effect is shown in figure 3. Through experimental tests, the length of the wax sealing of the pen core is 1-2mm, the peeling force of the wax sealing is 4-8N, the initial writing decoloration length of the pen core is reduced to 20-30mm, and the initial writing decoloration length of the pen core is reduced to 1/2 of the conventional pen core wax sealing decoloration length.

It should be noted by those skilled in the art that the described embodiments of the present invention are merely exemplary and that various other substitutions, alterations, and modifications may be made within the scope of the present invention. Accordingly, the present invention is not limited to the above-described embodiments, but is only limited by the claims.