CN1651526A

CN1651526A - Manufacturing method of damp proof chalk

Info

Publication number: CN1651526A
Application number: CN 200510023400
Authority: CN
Inventors: 方铭
Original assignee: Shanghai Institute of Technology
Current assignee: Shanghai Institute of Technology
Priority date: 2005-01-18
Filing date: 2005-01-18
Publication date: 2005-08-10

Abstract

A moisture-proof chalk is prepared through proportionally adding polyvinyl alcohol to boiling water, stirring for dissolving, cooling, loading general chalks in metallic netted basket, dipping them in said solution to generate a layer of polyvinyl alcohol solution on each chalk surface, and drying in air.

Description

A kind of making method of damp proof chalk

Technical field

The present invention relates to a kind of chalk making method, particularly a kind of making method of damp proof chalk.

Background technology

The existing shortcoming of using in the existing teaching of chalk is, 1, humidity resistance is bad, and make the chalk back intensity of making moist very low, regular meeting fractures into several sections in use, and chalk is very low with continuation rate of utilization later, causes very big waste; 2, chalk is taken or is used back powder ash to be infected with seriously, lime all over the body when making the teacher walk out the classroom, and the teacher's that gives a lesson books and clothing are also often dyed dirty by the powder ash.And existing no powder chalk is by the improvement to the chalk dust adhering technique, making it reduce the powder ash is infected with, but also unresolved in actual use loss problem, and all undesirable on fluent writing and manufacturing cost, and it is very little to promote the use of face in universities, middle and primary schools at present.

Summary of the invention

The objective of the invention is road manufacture craft behind the chalk to be done one improve in order to overcome the shortcoming of existing chalk manufacture method, a kind of making method of damp proof chalk is provided, to produce humidity resistance good for method thus, reduces the damp proof chalk of chalk dust.

Technical scheme of the present invention is: a kind of making method of damp proof chalk, be characterized in, it be with existing made chalk in the polyethylene liquor, dip in soak, airing forms.

The concrete step of method is:

1, polyethylene liquor preparation: the clear water of ebuillition of heated is added polyvinyl alcohol, be stirred to dissolving fully, being mixed with concentration is the polyethylene liquor of 6%-10%, and being placed on cools in the dipping jar makes its insulation at 15-35 ℃;

2, Manufactured chalk is put into metal wire casing, be delivered to the workshop of the dipping jar of polyethylene solution by conveyer chain, dip in metal wire casing and soak polyethylene solution, make the chalk in the case dip in the polyethylene liquid that soaks one deck 0.01-0.05 thickness, treating that chalk dips in to soak finishes, and airing gets final product.

The invention has the beneficial effects as follows: have the chalk of polyethylene film outsourcing that fabulous moistureproofness is arranged, can be after dispatching from the factory because of not making moist frangibility; Carry and take and also make things convenient for totally; Because polyethylene plastic film is very thin, writing on all kinds of blackboards is not affected during use; The chalk dust that the user is infected with also will significantly reduce; Owing to depositing, take and using clean and convenient, the continuation rate of utilization of every chalk also improves greatly.And technology is simple, and polythene material is also very cheap, and consumes seldom, and cost improves few.

Description of drawings

Fig. 1 soaks polyethylene liquid process flow diagram for chalk dips in.

Embodiment

The concrete embodiment that makes of a kind of damp proof chalk is described further in conjunction with the accompanying drawings, the steps include:

1, ethene liquor preparation: behind 100 kilograms of clear water ebuillition of heated, adds 5 kilograms of polyvinyl alcohol, be stirred to dissolving fully, be mixed with concentration and be 5% polyethylene liquor, being placed on and cooling to 15-35 ℃ in the dipping jar and is incubated;

2, by shown in Figure 1, Manufactured chalk is put into metal wire casing 1, be delivered to the workshop of the dipping jar 3 of polyethylene solution by conveyer chain 2, metal wire casing immersion dipping jar dips in and soaks polyethylene solution, make the chalk in the case dip in the polyethylene liquid that soaks one deck 0.01-0.05 thickness, treating that chalk dips in to soak finishes, and airing gets final product.4 is the supporting-point roller of conveyer chain among the figure.

Increase the insulation workshop that the polyethylene liquid that can not is solidified very soon as long as make the place of the finishing operation of factory at former chalk in the making of reality, the metal wire casing of chalk is adorned in preparation, can adorn the dipping jar and the conveyer chain of polyethylene liquid.In the not enough making place of appliance arrangement condition, the available leaching method that manually dips in.Dip in the metal wire casing that soaks usefulness and want the unnecessary polyethylene film of periodic cleaning.

Dip in the time of soaking how much deciding on wire netting size and dress chalk amount.Must make every chalk surface can both intactly be stained with one deck solution, dry the back and form one deck colorless and transparent film.Polyethylene film is attached to chalk surface and forms one deck water white " dressing ", has played good protection against the tide and provide protection, can long storage time, last till use always.Write to need only when using and exert oneself slightly, the polyethylene film of chalk head (dressing) just breaks thereupon, and can write down always, and being infected with of powder ash significantly reduces in writing.And even if bring into use, this layer " dressing " only breakage at one end also still has certain moisture-proof role.The service efficiency of chalk also improves thus greatly.

Claims

1, a kind of damp proof chalk making method is characterized in that, it be with existing made chalk in the polyethylene liquor, dip in soak, airing forms.

2, a kind of damp proof chalk making method according to claim 1 is characterized in that, described will have now made chalk in the polyethylene liquor, dip in soak, concrete steps that airing is made the damp proof chalk making method are:

(1) ethene liquor preparation: the clear water of ebuillition of heated is added polyvinyl alcohol, be stirred to dissolving fully, being mixed with concentration is the polyethylene liquor of 6%-10%, and being placed on cools in the dipping jar makes its insulation at 15-35 ℃;

(2) Manufactured chalk is put into metal wire casing, be delivered to the workshop of the dipping jar of polyethylene solution by conveyer chain, dip in metal wire casing and soak polyethylene solution, make the chalk in the case dip in the polyethylene liquid that soaks one deck 0.01-0.05 thickness, treating that chalk dips in to soak finishes, and airing gets final product.