adhesive tape membrane products appear sticky relay reduce adverse, and peel strength related with many factors. Such as: adhesive influence; adhesive tape matrix surface tension value not requirements, influence peel strength; The handling process is not standard; Drying temperatures, hot steel roller temperature not appropriate; And film substrate additive effects, etc. Now give analysis and respectively to find a suitable solution to peel strength bad fault phenomena bottomed out.

 

1. The varieties, quality and adhesive to compound the base does not adapt influence peel strength

 

Different USES of adhesive tape membrane on the choice of the adaptation of the substrate and adhesive. For example: no aluminum foil adhesive tape, in using universal adhesives can. If there is a adhesive tape foil, and eventually use is packing contains liquid acid food, be about to choose resistance of aluminum foil special adhesive drizzle substances. In choosing aluminum foil designed adhesive, should also preferred molecular weight relatively even slightly, molecular weight distribution, solvent release the gender is good, good adhesive coating performance. Molecular little adhesive although coating performance is better, but the molecular activity ability, through extremely thin aluminum layer, cause peel strength drops, sticky relay reduced. If compound bag should pass high-temperature cooking sterilization, should choose high temperature resistant (121 ℃ or 135 ℃) cooking type adhesive, can never use ordinary adhesives, general adhesive heat-resistant, adhesive tape films not less than 80 ℃ will usually stratified, basically could not reach packing on peel strength requirement. Our company for high-temperature cooking sterilization packaging often used by the zhejiang new Oriental ink group uh guano resin company production PU1750 and PU1875 adhesive, the result is right, in PET/CPP structure could reach 10-12N / 15mm, in PET/AL, NY/AL adhesive tape structure in 10-12N/intensity of 15mm.

 

For 15 mu mPA / 70 muon mLDPE adhesive tape structure, adopt 300 type PU - 1875 polyurethane adhesives, the effect is good. Use this adhesive must pay attention to when: 1) film corona surface tension should achieve 3.8 x 1.0-2N/m above, can obtain the ideal bonding effect; 2) thinner, often by acetic acid ethyl fat or ethyl acetate, of which shall not exceed three extremely water content, alcohol content; shall not exceed than two 3) glue of avoid by all means of containing active hydrogen crypto-software solvent. Such as: water, alcohol, amine classes; 4) PU - 1875 ratio of adhesives mainly agent: curing agent: acetic acid ethyl ester = 1-0. 2:1. 8 (than) the best performance when the weight.

 

For ink penetration of adhesive poor floating on the surface of the ink, and ink and base material and color fastness between adherence, also can lead to poor performance in compound film stratification, where a printing ink, especially multi-color overprint parts. Ink pulling down by adhesives. Use high solid content adhesives, will slow down a bit drying speed, let adhesives have sufficient time to ink layer infiltration thoroughly and reach their substrate surface. Appropriately increase the quantity of cement, all is helpful to improve the adhesive tape fastness. Choose the proper inks, and improving the surface tension of base material printing, printing ink, also improve adhesion fastness is one of the methods to solve the problems. In a adhesive tape process, request adhesive metamorphism, muddy white, be emulsified will not be used again, so compound adhesive must apply according to need preparation.

 

2. The quantity of cement is insufficient, coating inequality will directly influence the sticky relay peel strength, impact

 

Adhesive coating, coating inadequate uneven peel strength can also lead to decreased, sticky relay reduced. This point in the use of hot melt adhesives aggregate-organ appear the most easily, can not be ignored in the use of hot melt adhesive aggregate-organ, the main form of concentration glue will directly influence the peel strength height. We noticed, BOPP/OPP, BOPP/VMOPP, BOPP/OPP adhesive tape film thickness in more than 30 if lining, peel strength when u m most likely to decline. If use single points adhesives, adhesive tape process take a short adhesive tape finished dissection test, and make the relevant record

 

3. Diluent purity is not quite high, will affect adhesive tape peel strength

 

Diluent's role is to increase the flow of the degrees, improve adhesive afff sex, better coating evenly, make its glue better and base material happen infiltrates. If the thinner purity is not high, contain water, alcohol and active characteristics, will consume part of curing agent, cause the main agent and curing agent adhesive actual imbalance, the rapping decline. In selecting solvent, there are three value after academic reference: 1) stock, must choose regular, quality guaranteed producers; 2) purchase a barrel after random, found to contain water or alcohols active substances, must be banned. Only use high purity solvent, can guarantee the adhesive tape film has strong glue relay; 3) use before testing, solvent must clean, if produce a corrupt dirty etc. Phenomenon, best filtering or further processing, beware influence peel strength, impact coating effect.

 

4. Drying temperatures

 

adhesive tape process, drying ways should be made according to the actual situation of temperature adjustment. General into the baking temperature of 60 ℃ in the mouth for appropriate (materials and requirement need not have increased accordingly), two area, is accordingly increased abbasov, if the baking temperature is exorbitant, dry mouth, the inner surface film only, affect not only cannot drying, and peel strength will produce peculiar smell.

 

 

 

5. Plastic corona processing is insufficient, affect peel strength

 

Plastic membrane surface corona processes is not good, surface tension low, will cause the ink layer adherent fastness low, adhesive tape membrane adhesive strength in the film into low, the former shall carefully check their surface tension value must heighten to 3.8 x 10-2N/m above, best can achieve 4.0-4.2 x 10-2N/m, because 3.8 x 10-2N/m film couldn't make inks and adhesive completely finished afff after compound, of course, reach peel strength requirement. Inspection of film surface tension method usually have two kinds: 1) DaYin pen test, DaYin liquid pens is often red, specifications 3.8 x 10-2N/m, 4.0 x 10-2N/m, 4.2 x 10-2N/m, 4.4 x 10-2N/m and 4.8 x 10-2N/m these five, if use DaYin stroke on membranes pen liquid contractive, uniform, without fault, then explaining film surface tension has reached using requirements; Instead, pen liquid contraction, disappear, uneven, discontinuity, then explaining processing enough; 2) using BOPP single-sided tape test, will stick on tape for single BOPP film surface measurement half, corona handle the good again voice small, paste usually stripping firm, instead, easy is stickup rickety detachment. This method of testing depend on experience, not suitable for testing PET, PA etc films. Corona could not handle to meet the requirements of base material never adhesive tape, because adhesive tape affirmation after packaging products reach to peel strength requirement. Commonly used for the surface tension value base 3.8 x 10 -, BOPP 2N/m, PET 5.0 x 10-2N/m, PA5.2 x 10-2N/m.

 

6. Peel strength high residual solvents influence, affecting sticky relay

 

Residual solvents too much, adhesive tape many tiny bubbles form, make neighboring compound base material from the more, layering,, the bubbles and peel strength, to improve the lower peel strength of bubbles, must be reduced production. Air bubbles with many factors produced such as glue, uneven, drying way temperature too low, hot rolls temperature is low and indoor temperature inappropriate, etc., usually, indoor temperature should be controlled in 23-25 ℃, relative humidity should be controlled in 50-60 percent advisable. In addition, avoid using high boiling point solvents, also can reduce the bubble produce. In short, for improving the peel strength improve sticky relay should be as low as possible residual solvents.

 

7. Maturation incomplete affect peel strength

 

If use bi-component reactive adhesives, after compound also need to solidify (also called maturation), in order to achieve peel strength requirement. If maturation incomplete and peel strength also reduces, maturation incomplete has two meanings: 1) cure temperature is low; 2) typically don't have enough time. Generally speaking, adhesive tape finished product should be put on 50-60 ℃ environment reposado over 48 hours, some even needs more time to achieve satisfactory results. We noticed, low temperature storage time, adhesive tape films long again the ultimate peel strength cannot reach 350 N / 15m, if the environmental temperature increase to 55 ℃, same deposit degrees for four days, can be as high as peel strength 6N / 15mm.

 

8. In the influence of plastic additives

 

The additive plastic film can also affect the adhesive fastness, and this influence will only after a certain period show after seven days, be in commonly, and gradually declining trendency. Polyethylene, polypropylene in such films or process film, granulation most join a few auxiliary agents, such as: antioxygen, stabilizer, prevent adhesive, open agent, etc. These additives are low molecular material, with the passage of time, the internal gradually from film to surface infiltration, carefully observe when can find a very thin powder or paraffin substances, with the hand in hand will stick, slippery, white. If cloth blocks leaching acetic acid ethyl fat is wiped, will erase. We through the observation found that just adhesive tape good film inside short time migration out is not much, also add dose not causing bond fastness decline. But a long time, the migration out of the film and the additive isolate the basement membrane, destroyed the original binding condition, the adhesive tape fastness reduced. Solve this fault should put good feeding off without additives or less, the choice of raw material, with additives in the processing membrane, more should not factitious ground join openings agent. There have been such a fault: work out of detergent packing bag didn't appear adhesive fastness bad problem, however, after finished bag deposited by the load washing powder, a while it appeared printing substrate and adhesive tape matrix stratification phenomenon, even heat sealing point still appear rupture, causing washing powder were leaked. Packages washing powder main become anionic surfactant, clothing fluorescence agent, nonionic surfactant, alkaline slow granule, water softener and efficient besmirch sc, etc. Technical analysis has fault reason that PET12 muon/when LDPE80 muon m adhesive tape structure is to meet the requirements of the ingredients for washing powder, starting from the first printing ink, decided to solve the problem. So choose a special PET printing ink printing press, and then starting from adhesives, again, compound, after curing peel strength test, again into the washing powder for depositing, extrusion test, results fault eliminate, bags, and peel strength no longer stratified according to different requirements, visible the contents of choice adhesive tape matrix, printing ink is to solve a peel strength bad way.

 

Cause adhesive tape film rapping decline and peel strength bad many factors, adhesive ratio imbalance, the quantity of cement is insufficient, coating and hot pressing roller uneven temperature is low and peel strength may cause a adhesive tape films reduce, will make the rapping with larger adhesive tape finished peel strength and high, must take good each level, should not only from select material, printing ink, diluent, adhesives etc do quality cont-rol, also has seriously in operation and responsible attitude.