Rome wasn't built in a day, and neither is pure cotton acid-free paper.

In fact, as soon as Master Zhao took over Xishan Island, he asked Zhang Zai to bring several papermaking craftsmen to secretly develop this pure cotton acid-free banknote paper in the military camp.

In order to allow Zhang Jian to concentrate on his research, Zhao Hao specially invited the scholar named Jiao from Jinling to replace him as Li Zhi's assistant.

Zhang Zai was worthy of being the uncle of the great inventor... It took him a hundred days to produce a product that basically met the requirements.

Of course, from Mr. Zhao's discerning eyes, the quality of the banknote paper produced on Xishan Island is inferior to that of the third set of RMB, let alone the fourth and fifth sets of RMB.

But in the Ming Dynasty, it was enough to crush the world, and no one could catch up in a hundred years.

Those masters of counterfeiting can’t even make the paper for printing money. Who would give them the courage to print counterfeit money?

What else does Mr. Zhao want from a bicycle?

~~

"Brother, you have kept this secret from me so hard. Why don't you show me this treasure?" Jiang Xueying was relieved of her worries, and she glanced at Zhao Hao with infinite hope and said:

"I haven't slept well for several nights. I even have dark circles under my eyes."

"My bad, my bad." Zhao Hao smiled and put his hands together to apologize. "I just got it, so I don't know if it's useful or not."

“Try writing a few words first.” Secretary Ma picked up a piece of Hui ink with gold outlines and was about to grind it on the She inkstone.

"Use this ink." Zhao Hao took out a small copper box from his sleeve as if he was offering a treasure.

Ma Xianglan took the small copper box, carefully unscrewed the lid and found that the ink inside was thick and shiny, completely different from ordinary ink.

"Do you need to add water?" Secretary Ma asked.

"Just use it." Mr. Zhao shook his head.

Secretary Ma followed instructions, dipped the brush into the copper box, and then wrote a line of poetry on pure cotton acid-free paper.

'The moon is slanting on the branches of plum trees, and the figure is lonely. I hate the indifference of the four seasons that has let me down.'

Don't think too much, don't think too much, this is the second half of Ma Zhiyuan's poem "Rose dew, lotus leaf rain, cold frost and fragrant courtyard." Sister Ma wrote it, and there is no other meaning at all.

Well, I just wrote it casually.

Then Sister Ma cheered and said, "This character is so bright and the colors are so even. It's perfect for painting black orchids."

"This is used to print money..." Master Zhao reminded her seriously.

While trial-producing the printing paper, Zhao Hao also instructed Zhang Zai to prepare a unique oil-based ink.

Traditional printing uses water-based ink. The words printed with water-based ink are afraid of water and easily blur. Oil-based ink is not afraid of water and makes the printed products show strong and uniform colors and have a strong gloss.

The manufacturing method is also very simple. Boil the linseed oil, cool it, and then add a small amount of turpentine oil obtained by distilling pine resin, mix it with carbon black, and leave it for several months to make a suitable black ink.

To prepare red ink, simply replace carbon black with cinnabar; and replace blue with azurite...all of which are mineral pigments that have existed for a long time.

It has been more than three months since we trial-produced the first batch of oil-based ink, and it is now available for use.

Pure cotton acid-free paper with oil-based ink, how can you deal with it?

Moreover, this is the material used for the first set of silver notes. When Mr. Zhao’s students in the future figure out how to extract dyes from coal tar, they can print the second set of silver notes with bright colors and exquisite designs.

At that time, the counterfeiters will completely understand what despair is.

Young Master Zhao laughed like a pig in his heart.

Jiang Xueying and Ma Xianglan couldn't help but look at each other secretly.

They both saw surprise in each other's eyes——

Brother, sir, how long ago did you start preparing to print banknotes?

It's really terrifying to think about it, the more I think about it, the more unfathomable it seems...

~~

Now that they no longer have to worry about anti-counterfeiting issues, girls can finally focus on the layout design of the banknotes.

Now even Qiaoqiao became interested. She lay over the table and looked at Sister Ma intently. Following Jiang Xueying's instructions, she drew on a piece of acid-free paper.

"Use two straight lines, one thick and one thin, to frame the banknote. Draw patterns on the four corners. The more complex the better."

"Write the words 'Jiangnan Bank' on the top, draw a long frame in the middle, and write 'Pay a certain amount of official silver on presentation of the bill'..." Jiang Xueying asked Ma Xianglan to fill in the necessary information, and then smiled at everyone, "You can freely draw some patterns on the blank space. Do you have any good suggestions?"

Mr. Zhao, who never forgot to promote science, immediately thought of printing some scientific patterns and slogans on the silver bills.

The first thing that came to his mind was a hot air balloon, but after thinking about it, he decided to give it up.

How about printing the three laws of mechanics? It seems no one can understand them...

Well, it would be more useful to be down-to-earth and promote the ten scientific numbers, and then print out the simple addition and subtraction formulas, as well as the multiplication formulas.

Thinking of this, Master Zhao couldn't help but feel bored. The good banknotes have become preschool knowledge cards. No matter how they are designed, there will be no Boyi pattern...

"Why don't we paint the young master on it?" Qiaoqiao suddenly made a shocking suggestion.

"Good idea!" Jiang Xueying and Ma Xianglan immediately agreed.

Ma Xianglan immediately started to outline the picture in the frame with a thin pencil.

After a while, Mr. Zhao, holding a telescope and smiling, appeared on the banknote.

"Yeah, it feels like that..." Zhao Hao nodded and said, "But the expression should be more serious, and the eyes should be wiser. It would be best if he had a sense of knowing everything."

"Okay, I'll change it right away." Secretary Ma naturally followed suit.

"Bullshit!" Young Master Zhao came to his senses and cursed with a smile: "If you print me on it, will I ever have to go out again?"

"Oh..." Secretary Ma blinked and thought that the young master was very conflicted.

"No portraits are needed on this version of banknotes." After all, Mr. Zhao still didn't have the courage to be the person on the banknotes, so he could only think secretly:

"Wait for the next edition. When it can be printed in full color, I will definitely print my portrait on it."

~~

Jiangnan Bank is preparing to issue its first batch of silver bills in five denominations, each with a different size.

Of course, the larger the denomination, the larger the size.

The four of them had a heated discussion until late at night before they finally decided on the general styles of five silver bills.

The half-liang denomination silver note features the Wusong River embankment in Kunshan as the main pattern, and the multiplication table is on the back.

The silver note with a face value of one tael has a world map as the main pattern, and on the back is a subtraction table within twenty.

The two-liang silver note features Jiangnan Hospital as the main pattern, and an addition table within twenty on the back.

The five-liang silver note features the Yufeng Academy, which had just been completed and was still undergoing interior decoration, as its main pattern, and a division table on the back.

The silver note with a face value of ten taels features Zheng He's super fleet sailing to the West as the main pattern.

On the back is another world map, but unlike the one-liang silver note's front pattern, this map is larger and more detailed, clearly marking the results of Spain and Portugal's division of the world.

This is a very disturbing pattern.

Because the two countries go around the Cape of Good Hope, from Africa through India and across Malacca.

One runs from Europe to Mexico, then across the Pacific Ocean to Luzon.

After traveling around most of the world, they have all arrived at the gate of the Ming Dynasty.

p.s. My eyes can’t take it anymore, I’ll write tomorrow.