普13《北京建筑图案普通邮票》3分票刷色为绿色(以下称“普13”),20世纪80年代有媒体刊登过有关普13中3分票发现有蓝色刷色变异的文章,刊出后,有人提出异议,其大意是蓝色刷色变异是人为变造品,系用化学元素作用所产生的变色,之后便未见有探讨。也许“蓝色发现者”苦于手中无实寄封可以佐证,如果勉强争辩,恐怕缺乏说服力,一时“略处下风”;化学变 In the 1980s, there were articles published by the media on the 3-point votes of the general public in the 1980s that found blue brush color variations , After the publication, someone raised an objection, the effect of which is that the blue brush color variation is a man-made change product, which is produced by the action of chemical elements, and then there is no discussion. Perhaps “blue discoverer ” suffer from the hands of the actual mail can be corroborated, if reluctantly argued, I am afraid lack of persuasion, sometimes “slightly underdog”; chemical changes