The paper bag glue is not firmly bonded, and the carton is degummed. Degumming refers to the cracking of the adhesive mouth due to insufficient bonding fastness. The main reasons are summarized as follows:
(1) The viscosity of the adhesive is insufficient or the amount of glue applied is insufficient.
(2) The adhesive and the carton material do not match.
(3) The sticky mouth part of the carton has been surface processed by lamination and glazing. It is difficult for the adhesive to penetrate the surface layer and penetrate into the paper, and the carton is difficult to stick.
(4) The pressure after folding and gluing is insufficient, and the pressing time is not long enough, which is not conducive to the strong paste.
For the above-mentioned problems of poor pasting caused by the adhesive, the adhesive suitable for the carton material should be selected, and the selection and use of the adhesive are also very particular.
First of all, it cannot be mistakenly believed that the higher the viscosity of the adhesive, the better the gluing effect. The higher the viscosity, the higher the adhesive strength and the higher the wrinkling rate.
When the glue roller of the automatic folder gluer runs at a high speed of 112 revolutions per minute, the recommended viscosity of the adhesive is 500-1000cps. Secondly, the adhesive force of the adhesive is stronger.
Because the instantaneous pressure of the forming part of the automatic folder gluer is not very large, and during the high-speed operation of producing 30-40 cartons per minute, the pressure time is not long. Applying pressure can also bond the carton firmly.
In addition, the ambient temperature of the gluer workshop will also have a certain impact on the adhesive. If the temperature of the pasting workshop is too low, the adhesive will solidify immediately, affecting the bonding fastness, even if the amount of glue applied is too large, it will not work.
Of course, the less glue is applied, the more sensitive it is to room temperature, so in winter, the temperature of the gluer workshop should be kept above 20 °C, and air conditioners can be installed if conditions permit.
In the folder-gluing workshop, a large and easily visible thermometer is also installed to check and control the working environment at any time. For the pasted products, they should be dried at room temperature before leaving the factory. In winter, do not rush to deliver the products before they are dry.
