SU891738A1 - Thermoglue - Google Patents

Description

The invention relates to adhesives that exhibit adhesiveness when heated, and can be used in the manufacture of laminated materials, heat-adhesive labels, which are widely used for labeling industrial packaging.

Known adhesive melt, including a copolymer of ethylene with vinyl acetate, rosin, vaseline oil fl.

However, the adhesive does not have sufficient adhesion.

Adhesive melt is also known, including a copolymer of ethylene and vinyl acetate, a terpene resin, atactic polypropylene, a low molecular weight nitrile-butadiene rubber, polyisobutylene, and an antioxidant 2.

Lack of glue - increased viscosity.

The closest in technical essence and the obtained positive result to the invention is hot melt 13, containing, by weight:

Ethylene copolymer

with vinyl acetate 30-50

Rosin or

rosin esters 15-30

Wax or paraffin wax 10-20

The known hot melt glue is a solid material of a light yellow color with the following characteristics:

five

At 140-1 ° C

Fluid viscosity at 140-160 ° С, сП

14000 Adhesion to metal 250 lu, HS / cm

ten

However, the high viscosity of the specified hot melt makes it difficult to apply it to the printing substrate — paper, polyethylene terephthalate film, and foil. Besides that, he. It does not provide sufficient adhesion to surface sensations, such as methane, which makes it impossible to use glue in the production of ethics, nameplates, and other products intended for the decoration of industrial products.

The purpose of the invention is to reduce the viscosity of the adhesive and increase adhesion to the metal.

The goal is achieved by the fact that hot melt glue, including a copolymer of ethylene with vinyl acetate, rosin or rosin ester and wax, contains a copolymer of ethylene with vinyl acetate with

thirty

the content of vinyl acetate 18-34% and additionally - urea and benzopheno in the following ratio of components, parts by weight:

Ethylene copolymer with vinyl acetate 100 Rosin or ether

rosin 50-200

Wax 40-100 Urea2-20

Benzophenone. 1-10 The content in the composition of the hot melt of a copolymer with a vinyl acetate content of 18–34% and, additionally, urea and benzophenone allows a significant reduction in viscosity in the molten state (up to 4450 cP). In this case, not only the preservation, but also a significant increase in adhesion of the adhesive to the metal (up to 1180 N / m) is observed. The content of vinyl acetate is due to the fact that in the case of its reduction in the copolymer, the viscosity of the hot melt increases sharply, and with an increase the elasticity of the adhesive coating decreases.

As rosin, rosin esters can be used, for example, glycerol ester of rosin, pentaerythritol ester, ester of rosin-maleic adduct. Application 1 is possible; also terpenic resins.

In tab. 1 shows the formulations of adhesives.

The adhesive is prepared as follows. In the tank load wax, ester of rosin or rosin, urea and heated to 140-1bO ° C. Then, with stirring, ethylene-vinyl acetate copolymer is added, and after it is melted, benzophenone is loaded. The resulting homogeneous composition is applied to a printed substrate (paper, polyethylene terephthalate film or aluminum foil).

The adhesion of the hot melt to the metal is determined by the following method; 10x150 polyethylene terephthalate film strips with adhesive applied with a special device having a temperature of 140s are rolled to metal plates with a force of 1 kg / cm, after which the peeling strength of the film with metal glue is determined on the RMB-3 tensile machine.

The melt viscosity is determined on a Rheostat-2 instrument. To do this, the hot-melt glue obtained in solid form is crushed by hand and in an amount of 17 g is loaded into a measuring tank, which is thermostatic for 30-40 minutes at 140-160 ° C, then the measuring cylinder is heated into a heating cabinet up to 140-160 ° C and, in the hot state, is mounted on the instrument, after which the viscosity measurement is taken.

In tab. Figure 2 shows the viscosity of the proposed and known hot melt and its adhesion to metal.

As can be seen from the table. 2, the addition of urea with benzophenone and a copolymer with a vinyl acetate content of 18–34% in the composition of the hot melt makes it possible to reduce the viscosity to 4450 cP, while increasing adhesion to the metal to 1180 N / m.

The decrease in viscosity of the thermocle in the molten state makes it possible to apply it to the printing substrate using a system of rollers on the known equipment, and high adhesion rates to the metal make it possible to produce heat-adhesive applications on the basis of the proposed adhesive - labels, labels, labels, quality marks designed for marking, art and technical design of containers, industrial products and semi-finished products, which will expand the field of application of hot melts.

Table 1

Ethylene copolymer with vinyl acetate containing vinyl acetate,:

18

28

34

Glycerin ester rosin

100

100 100

100 100

100 100

150

Pentaerythritol Rosin Ether

Ester of rosin-malein adduct

Prod / kken tab. one

200

100

Claims (2)

Claim Hot-melt adhesive, including a copolymer of ethylene with vinyl acetate, rosin or rosin ether and wax., Is distinguished by the fact that, in order to reduce the viscosity of the glue and increase adhesion to the metal, it contains a copolymer of ethylene with vinyl acetate with a content of 18-34 % vinyl acetate and additionally 55 but - urea and benzophenone in the following ratio of components, parts by weight: Copolymer of ethylene with vinyl acetate 100 Rosin or rosin ester Wax Urea Benzophenone 50-200 40-100 2-20 1-10