Background technology
Buffering paper papery is soft, good permeability, has good shock-absorbing capacity, available buffer pressure, evenly pressure transmission, reduction Cooling rate, uniformly transfer heat, is that one of padded coaming conventional in circuit board is produced in hot pressing.The shock-absorbing capacity of buffering paper directly affects the quality of hot pressing circuit board.But due to the restriction of manufacture craft, material performance etc., still there is following problem in buffering paper in the market: in buffering paper, the too high or water imbibition of moisture is too strong, adheres on substrate by large area easy after hot pressing; Buffering paper easily turns to be yellow after the hot pressing of high-temperature buffer paper, brittle, deformation, and compression resistance of paper is poor, causes its shock-absorbing capacity to reduce, and circuit board damage, service life shorten.
Along with the development of science and technology, people propose requirements at the higher level to the shock-absorbing capacity of buffering paper under high temperature hot pressing state.And shock-absorbing capacity under the resistance to pressure of traditional buffering paper, High Temperature High Pressure is superior not, also there is very large room for promotion.
Summary of the invention
The technical problem to be solved in the present invention is, improve for the deficiency on existing buffering paper Manufacturing Techniques, the obtained buffering paper that resistance to pressure is good, water imbibition is moderate, intensity is high, non yellowing under the High Temperature High Pressure of this buffering paper, deformation are little, shock-absorbing capacity is good, more can meet market demand.
The technology used in the present invention solution is:
Buffering paper and manufacture craft thereof, it is prepared by the raw material of following parts by weight:
Mercerization wood pulp 160 ~ 180 parts
Softwood pulp 240 ~ 260 parts
Hardwood pulp 75 ~ 85 parts
Wet strength agent 14 ~ 18 parts
Organic silicon emulsion 15 ~ 18 parts
Reinforcing agent 4 ~ 8 parts
4 ~ 8 parts, aluminum sulfate
Its fabrication processing is as follows:
Feed intake-pulping-defibrination-be mixed into auxiliary agent-upper net forming-squeezing-oven dry-reel-cut-pack.
The parts by weight of each raw material be: mercerization wood pulp 170 parts, softwood pulp 250 parts, hardwood pulp 80 parts, wet strength agent 16 parts, organic silicon emulsion 16 parts, reinforcing agent 6 parts, 5 parts, aluminum sulfate.
The active ingredient of described wet strength agent is thermosetting resin, preferred PPE wet strength agent.
Described reinforcing agent active ingredient is modified starch, preferred quaternary ammonium alkyl cationic starch.
Described buffering paper be quantitatively 300 ± 10g/ ㎡, thickness is 0.9 ± 0.05mm, and moisture is 8 ± 2%.
With the reinforcing agent of 2%, paper is sprayed before also comprising the laggard drying cylinder of squeezing in described fabrication processing.
Traditional buffering paper adopts softwood pulp to manufacture paper with pulp mostly, and softwood pulp fiber is thick, long, and Unit Weight fiber number is few, and crosspoint is few, and obtained buffering paper intensity is high, but tightness is large, and porosity is low, poor air permeability, and hot buffering effect is restricted; And on the other hand, the aperture of the buffering paper hole that softwood pulp obtains is large, thermal conductivity factor increases, and hot shock-absorbing capacity is influenced.Hardwood pulp fiber finer, short, Unit Weight fiber number is many, and crosspoint is many, and obtained buffering paper tightness is little, porosity is high, good permeability, but simultaneously water suction and phenomenon of losing water serious, comparatively be subject to the impact such as ambient humidity, temperature, its moisture is unstable, and then affects its shock-absorbing capacity.Mercerising wood pulp has good chemical stability.Therefore, this process adjustments is by the technique of jointly manufacturing paper with pulp of employing three kinds of wood pulps, and obtained tightness, porosity, the buffering paper that average pore size is moderate, its dry wet strength, air permeability, water absorbing properties are good, more can meet the market demand of hot pressing buffering paper.
Advantage of the present invention and beneficial effect:
1. the mercerization wood pulp of the softwood pulp selecting fiber slightly to grow and the short hardwood pulp of fiber finer and good stability is manufactured paper with pulp obtained buffering paper jointly, has good dry wet strength, gas permeability.
2. the buffering paper that the technique adopting slurry Inner applying glue and top sizing to combine obtains has excellent dry wet strength, resistance to pressure, still can have good shock-absorbing capacity under High Temperature High Pressure.
3. use organic silicon emulsion as water repellent agent, reduce water absorption rate and the percentage of water loss of buffering paper, stablize buffering paper moisture in transport, storage and use procedure, and there is good chemical stability, elasticity, make buffering paper still have good intensity, air permeability, resistance to pressure, flexibility at high temperature under high pressure, increase its service life.
Detailed description of the invention
Below in conjunction with embodiment, the present invention is described further.
Embodiment 1
By papermaking conventional fabrication process successively through feeding intake-pulping-defibrination-be mixed into auxiliary agent-upper net forming-squeezing-oven dry-reel-cut-pack obtains buffering paper.Wherein, in filling pocket, the input amount of slurry is mercerization wood pulp, the softwood pulp of 260Kg, the 75Kg hardwood pulp of 160Kg, mixing slurry is assigned to 25m3 slurry and removes slurry point by fluffer; In mixed stock tank, the order that adds of auxiliary agent is: first add 15Kg organic silicon emulsion, then add 18KgPPE wet strength agent, 4Kg quaternary ammonium alkyl cationic starch stir 15min(starch in advance through gelatinization and filter), finally add the 4Kg aluminum sulfate solution dissolved; Stick with paste with the modified starch of 2% before entering drying cylinder after the press and spraying process is carried out to paper.
Embodiment 2
By papermaking conventional fabrication process successively through feeding intake-pulping-defibrination-be mixed into auxiliary agent-upper net forming-squeezing-oven dry-reel-cut-pack obtains buffering paper.Wherein, in filling pocket, the input amount of slurry is mercerization wood pulp, the softwood pulp of 240Kg, the 78Kg hardwood pulp of 175Kg, mixing slurry is assigned to 25m3 slurry and removes slurry point by fluffer; In mixed stock tank, the order that adds of auxiliary agent is: first add 17Kg organic silicon emulsion, then add 14KgPPE wet strength agent, 6Kg quaternary ammonium alkyl cationic starch stir 15min(starch in advance through gelatinization and filter), finally add the 8Kg aluminum sulfate solution dissolved; Stick with paste with the modified starch of 2% before entering drying cylinder after the press and spraying process is carried out to paper.
Embodiment 3
By papermaking conventional fabrication process successively through feeding intake-pulping-defibrination-be mixed into auxiliary agent-upper net forming-squeezing-oven dry-reel-cut-pack obtains buffering paper.Wherein, in filling pocket, the input amount of slurry is mercerization wood pulp, the softwood pulp of 255Kg, the 85Kg hardwood pulp of 180Kg, mixing slurry is assigned to 25m3 slurry and removes slurry point by fluffer; In mixed stock tank, the order that adds of auxiliary agent is: first add 18Kg organic silicon emulsion, then add 17KgPPE wet strength agent, 8Kg quaternary ammonium alkyl cationic starch stir 15min(starch in advance through gelatinization and filter), finally add the 6Kg aluminum sulfate solution dissolved; Stick with paste with the modified starch of 2% before entering drying cylinder after the press and spraying process is carried out to paper.
Embodiment 4
By papermaking conventional fabrication process successively through feeding intake-pulping-defibrination-be mixed into auxiliary agent-upper net forming-squeezing-oven dry-reel-cut-pack obtains buffering paper.Wherein, in filling pocket, the input amount of slurry is mercerization wood pulp, the softwood pulp of 250Kg, the 80Kg hardwood pulp of 170Kg, mixing slurry is assigned to 25m3 slurry and removes slurry point by fluffer; In mixed stock tank, the order that adds of auxiliary agent is: first add 16Kg organic silicon emulsion, then add 16KgPPE wet strength agent, 6Kg quaternary ammonium alkyl cationic starch stir 15min(starch in advance through gelatinization and filter), finally add the 5Kg aluminum sulfate solution dissolved; Stick with paste with the modified starch of 2% before entering drying cylinder after the press and spraying process is carried out to paper.