Rome wasn't built in a day, and cotton acid-free paper wasn't made in a day.

In fact, as soon as Zhao Gongzi got Xishan Island, he asked Zhang Zai to take a few paper-making craftsmen to secretly develop this kind of pure cotton acid-free banknote printing paper in the military camp.

In order to allow Zhang Jian to engage in research without distractions, Zhao Hao also specially invited a scholar surnamed Jiao from Jinling to replace him as Li Zhen's teaching assistant.

Zhang Zai is worthy of being a great inventor...... It took 100 days to create a finished product that basically met the requirements.

Of course, from Zhao Gongzi's critical point of view, the banknote printing paper made in Xishan Island is not only compared with the fourth and fifth sets of RMB, but also compared with the third set of RMB, the quality is quite inferior.

But in the era of the Ming Dynasty, it is enough to crush the world, and no one can catch up in a hundred years.

Those masters of counterfeiting can't even get the paper on which they printed money, who lent them the courage to print counterfeit money?

What else does Zhao Gongzi want?

~~

"My brother is so bitter that my little sister is hidden, there is such a treasure that you don't take out for me to see." Jiang Xue greeted a big heartache, and glanced at Zhao Hao infinitely beautifully and said:

"It's so bad that my little sister hasn't slept well for a few nights, and she has dark circles under her eyes."

"My fault, my fault." Zhao Hao smiled and folded his hands in apology. "I just got it, so I don't know if it's good or not."

"Try writing a few words first." Secretary Ma picked up a piece of gold-painted ink and grinded it on the inkstone.

"Use this ink." Zhao Hao offered a treasure again, and took out a small copper box from his sleeve.

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

"Do you need to mix it with water?" Secretary Ma asked.

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

Secretary Ma dipped a brush in a copper box as he said, and then wrote a line of poems on cotton acid-free paper.

'Mei Shaoyue is lonely, and she hates to live up to her feelings. ’

Don't think too much, don't think too much, this is Ma Zhiyuan's 'rose dew, lotus leaf rain, chrysanthemum frost cold incense garden. In the second half of the month, Sister Ma wrote it out, and there was no other meaning at all.

Well, it's handwritten.

I heard Sister Ma cheer and said: "This character is so bright to write, the color is very symmetrical, and it is the most suitable for painting Mo Lan." ”

"This is used to print money...... "Zhao Gongzi reminded her with a serious face.

At the same time as the trial production of banknote printing paper, Zhao Hao also instructed Zhang Zai to configure a unique oil-based ink.

Traditional printing is all water-based ink, water-based ink printed words are afraid of water is easy to faint, oil-based ink is not only not afraid of water, but also makes the printed matter show a strong, uniform color, and has a strong luster.

The manufacturing method is also very simple, the flaxseed oil is boiled, cooled with a small amount of distilled pine resin to obtain turpentine, mixed with carbon black, and placed for several months to become a suitable black ink.

To prepare red ink, simply replace carbon black with cinnabar; The blue color is changed to limestone...... They are all mineral pigments that have been around for a long time.

It has been more than three months since the trial production of the first batch of oil-based inks, and it is just available at this time.

Pure cotton acid-free paper oiling ink, just ask you how to break?

And this is still the material used for the first set of silver tickets, and Zhao Gongzi will wait until the future...... After figuring out how to extract the dye from coal tar, they can print a second set of silver tickets with bright colors and beautiful patterns.

At that time, the counterfeiters knew exactly what despair was.

Zhao Gongzi laughed in his heart.

Jiang Xueying and Ma Xianglan couldn't help but glance at each other quietly.

They all saw the surprise in each other's eyes-

Brother, Childe, how long ago did you start preparing to print silver tickets?

It's scary to think about it, and the more I think about it, the more unfathomable I feel......

~~

After completely no longer worrying about anti-counterfeiting, the girls can finally put their minds on the layout design of the silver ticket.

At this time, even Qiaoqiao was interested, lying on the table and looking at Sister Ma intently, according to Jiang Xueying's instructions, she drew on a piece of acid-free paper.

"Around the silver ticket, use two straight lines, one thick and one thin, to frame the edges, and the four corners should be painted with patterns, the more complex the better."

"Write the four words Jiangnan Bank on the top, put a long box in the middle, and write a number of taels ......of official silver to be paid with the ticket" Jiang Xueying asked Ma Xianglan to fill in the necessary information, and then smiled at everyone: "The blank space can draw some patterns freely, do you have any suggestions?" ”

Zhao Gongzi, who never forgot to promote science, immediately thought of making some scientific patterns and slogans printed on the silver ticket.

The first thing he thought of was a hot air balloon, but after thinking about it, he better forget it.

Why don't you print the three laws of mechanics? No one seems to be able to understand it......

Hey, it's better to be down-to-earth, promote ten scientific numbers, and then print the simple addition and subtraction formulas, as well as the ninety-nine multiplication formulas.

Thinking of this, Zhao Gongzi couldn't help but be bored for a while. A good silver ticket has become a preschool knowledge card, and no matter how you design it, there will be no Boyige......

"Why don't we draw Childe!" At this time, I suddenly heard Qiao Qiao's earth-shattering proposal.

"Great idea!" Jiang Xueying and Ma Xianglan echoed in unison.

Ma Xianglan immediately outlined it in the frame with a slender lead pipe.

After a while, Zhao Gongzi, who was holding a telescope and smiling, appeared on the silver ticket.

"Well, there's an inner taste...... Zhao Hao nodded and said: "But the expression should be more serious, the eyes should be wiser, and it is better to have that feeling of knowing everything." ”

"Mm-hmm, I'll change it." Secretary Ma is naturally as good as a stream.

"!" Zhao Gongzi came back to his senses and scolded with a smile: "Imprint me on it, will I still need to go out in the future?" ”

"Oh......" Secretary Ma blinked, and said in his heart that Childe was so entangled.

"This version of the silver ticket doesn't need a portrait." Zhao Gongzi still didn't have the courage to be the person on the banknote after all, so he could only rub his teeth and think:

Wait for the next edition, and when you can print it in full color, you must print your own headshot. ’

~~

Jiangnan Bank is preparing to issue five denominations of silver bills, each of which is different in size.

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

The four of them did not discuss until the second half of the night before they tentatively settled on the general style of the five silver tickets.

The silver ticket of the half-two denomination has the Wusong River embankment in Kunshan as the main pattern, and the back is a ninety-nine multiplication table.

The silver tickets of one or two denominations have a world map as the main pattern, and on the back is a subtraction table within twenty.

The silver ticket of two denominations takes Jiangnan Hospital as the main pattern, and the back is an addition table within 20.

The silver ticket of five taels denomination is based on the Yufeng Academy, which has just been built and is still being renovated inside, and the back is a ninety-nine division table.

The silver ticket of ten taels denomination is mainly based on Zheng He's super fleet in the Western Ocean.

On the back is another map of the world, but unlike the front of the silver stamps, this map is larger and more detailed, clearly marking the results of the division of the world between Spain and Portugal.

It's a very disturbing pattern.

Because one of the two countries bypassed the Cape of Good Hope and crossed Malacca from Africa through India.

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

They have gone around most of the world for half a circle, and they have all come to the door of Daming.

ps. I can't stand it anymore, so I'll write it tomorrow.