UV photochromic reusable paper

Abstract

The invention relates to an ultraviolet photochromic reusable paper, which is made of a composite of ultraviolet photoreversible discoloration material and paper; the ultraviolet photoreversible discoloration material is composed of polyacrylamide or polyvinyl alcohol and Composed of polyacid compounds, and polyacid compounds and polyacrylamide constitute a donor-acceptor charge transfer compound, the ratio of polyacid compounds to polyacrylamide is 10-2:1; the polyacid compound is Keggin structure At least one of phosphotungstic acid and Keggin structure phosphomolybdic acid. The paper can quickly change from colorless to blue-black, black or pure blue under ultraviolet light irradiation, does not change color under natural light or no light, and can still return to the original color after being placed in the presence of oxygen for 6 to 30 hours. And this coloring-fading process can be repeated many times, the present invention is low in use cost, degradable and recyclable, has high printing fineness, and can be used as writing or printing paper.

Description

technical field [0001] The invention belongs to the technical field of paper development and relates to an ultraviolet photochromic reusable paper. Background technique [0002] Papermaking is one of the greatest inventions affecting the development of world civilization. As the carrier of characters and culture, paper brings great convenience to people's work and study, makes the spread of culture more convenient, and promotes the development of human civilization. [0003] The traditional paper industry consumes a lot of energy, causes serious pollution, and wastes paper in daily use. According to relevant survey data, about 45% of printed or copied paper documents are "disposable". Extremely low, the waste of paper is shocking, and reducing paper consumption by changing people's habits has not been effective in the short term. How to make paper reusable? Many research institutions and enterprises at home and abroad have conducted research, but there are problems such a...

AI Technical Summary

Problems solved by technology

However, this technology has the following problems: 1. The minimum printing size is 5, and fine printing cannot be achieved

2. The production cost of paper is high and it is difficult to popularize

3. It has high requirements on the use environment, and mistakes are prone to occur in the use process

But this technology has the following problems: 1, multi-layer paper, high cost

2. It is difficult to print fine text and pictures many times

3. There is pollution in the preparation process of chemical dyes

4. The printing speed is slower than traditional printers

But this technology has the following problems: 1. The writing clarity is poor, the resolution is low, and the printing speed is slow

2. The printer will have dot matrix printer noise, and the number of cycles is small

But this technology has the following problems: 1. The quality of printing is poor when it overlaps with the previous time

2. Reuse requires special equipment, and the cycle is long

3. Currently ink is expensive

But this technology has the following problems: 1. The cost is high, and the cost of a piece of A4 paper is about 14 yuan

2. Recycling is difficult and not environmentally friendly.

But there are following problems in this technology: 1, printer cost is high

2. Overlapping toner after repeated use will reduce the printing quality

4. High cost of consumables

But there are still the following problems: 1. Made of plastic and glass, it is non-degradable and difficult to recycle

2. High cost and high energy consumption

3. The sheet paper is thick and the "paper" is hard, which is not suitable for printing

At the same time, no available printing method has been developed yet, and printing needs to be realized by photocopying

Images